| Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] |
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Fair Value Measurements at March 31, 2026 Using
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Quoted Prices in
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Active Markets
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Significant Other
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Significant
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for Identical
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Observable Inputs
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Unobservable
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Assets (Level 1)
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(Level 2)
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Inputs (Level 3)
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Total
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Assets Measured on a Recurring Basis:
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(In Thousands)
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Available-for-sale debt securities:
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U.S. Treasury securities
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$ |
471,693 |
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$ |
- |
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$ |
- |
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$ |
471,693 |
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Mortgage-backed securities
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- |
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123,160 |
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- |
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123,160 |
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State and municipal securities
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- |
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9,822 |
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|
- |
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9,822 |
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Corporate debt
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- |
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432,476 |
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- |
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432,476 |
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Total available-for-sale debt securities
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471,693 |
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565,458 |
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- |
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1,037,151 |
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Total assets at fair value
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$ |
471,693 |
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$ |
565,458 |
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$ |
- |
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$ |
1,037,151 |
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Fair Value Measurements at December 31, 2025 Using
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Quoted Prices in
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Active Markets
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Significant Other
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Significant
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for Identical
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Observable Inputs
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Unobservable
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Assets (Level 1)
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(Level 2)
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Inputs (Level 3)
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Total
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Assets Measured on a Recurring Basis:
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(In Thousands)
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Available-for-sale debt securities:
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U.S. Treasury securities
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$ |
522,923 |
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$ |
- |
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$ |
- |
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$ |
522,923 |
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Mortgage-backed securities
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- |
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133,304 |
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- |
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133,304 |
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State and municipal securities
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- |
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9,809 |
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- |
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9,809 |
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Corporate debt
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- |
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402,789 |
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- |
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402,789 |
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Total available-for-sale debt securities
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522,923 |
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545,902 |
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- |
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1,068,825 |
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Total assets at fair value
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$ |
522,923 |
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$ |
545,902 |
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$ |
- |
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|
$ |
1,068,825 |
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| Fair Value Measurements, Nonrecurring [Table Text Block] |
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Fair Value Measurements at March 31, 2026 Using
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Quoted Prices in
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Active Markets
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Significant Other
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Significant
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for Identical
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Observable
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Unobservable
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Assets (Level 1)
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Inputs (Level 2)
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Inputs (Level 3)
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Total
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Assets Measured on a Nonrecurring Basis:
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(In Thousands)
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Loans individually evaluated
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$ |
- |
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$ |
- |
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$ |
191,101 |
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$ |
191,101 |
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Other real estate owned and repossessed assets
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- |
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- |
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3,072 |
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|
3,072 |
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Total assets at fair value
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$ |
- |
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|
$ |
- |
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|
$ |
194,173 |
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$ |
194,173 |
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Fair Value Measurements at December 31, 2025 Using
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Quoted Prices in
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|
|
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|
Active Markets
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Significant Other
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Significant
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for Identical
|
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Observable
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Unobservable
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Assets (Level 1)
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Inputs (Level 2)
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Inputs (Level 3)
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Total
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Assets Measured on a Nonrecurring Basis:
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(In Thousands)
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Loans individually evaluated
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$ |
- |
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|
$ |
- |
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$ |
186,825 |
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$ |
186,825 |
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Other real estate owned and repossessed assets
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- |
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|
- |
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2,583 |
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2,583 |
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Total assets at fair value
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$ |
- |
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$ |
- |
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|
$ |
189,408 |
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|
$ |
189,408 |
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| Fair Value, by Balance Sheet Grouping [Table Text Block] |
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March 31, 2026
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Carrying /
Notional
Amount
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Estimated
Fair Value
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Quoted Market
Prices in an Active
Market
(Level 1)
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Models with
Significant
Observable Market
Parameters
(Level 2)
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Models with
Significant
Unobservable
Market Parameters
(Level 3)
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(In Thousands)
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Financial Assets:
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Cash and cash equivalents
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$ |
1,817,944 |
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$ |
1,817,944 |
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$ |
1,817,944 |
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$ |
- |
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$ |
- |
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Securities purchased with agreement to resell
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$ |
499,087 |
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$ |
499,087 |
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$ |
499,087 |
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$ |
- |
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$ |
- |
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Held to maturity U.S. Treasury securities
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|
249,675 |
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|
240,255 |
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|
240,255 |
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|
- |
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|
- |
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Federal funds sold
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|
18,678 |
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|
18,678 |
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|
- |
|
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|
18,678 |
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|
|
- |
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Held to maturity debt securities
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|
397,595 |
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|
362,221 |
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|
- |
|
|
|
361,721 |
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|
500 |
|
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Mortgage loans held for sale
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|
12,893 |
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|
12,893 |
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|
- |
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|
12,893 |
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|
- |
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Restricted equity securities
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|
12,466 |
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|
12,466 |
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|
- |
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|
12,466 |
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|
- |
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Loans, net
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13,772,008 |
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13,570,508 |
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|
- |
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- |
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13,570,508 |
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Financial Liabilities:
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|
|
|
|
|
|
|
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|
|
|
|
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Deposits
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$ |
14,486,364 |
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$ |
14,483,407 |
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$ |
- |
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$ |
14,483,407 |
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$ |
- |
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|
Federal funds purchased
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|
1,546,987 |
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|
1,546,987 |
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|
|
- |
|
|
|
1,546,987 |
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|
|
- |
|
|
Other borrowings
|
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|
34,750 |
|
|
|
31,413 |
|
|
|
- |
|
|
|
31,413 |
|
|
|
- |
|
|
December 31, 2025
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Carrying /
Notional
Amount
|
|
|
Estimated
Fair Value
|
|
|
Quoted Market
Prices in an Active
Market
(Level 1)
|
|
|
Models with
Significant
Observable Market
Parameters
(Level 2)
|
|
|
Models with
Significant
Unobservable
Market Parameters
(Level 3)
|
|
| |
|
(In Thousands)
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Financial Assets:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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Cash and cash equivalents
|
|
$ |
1,121,734 |
|
|
$ |
1,121,734 |
|
|
$ |
1,121,734 |
|
|
$ |
- |
|
|
$ |
- |
|
|
Securities purchased with agreement to resell
|
|
$ |
498,910 |
|
|
$ |
498,910 |
|
|
$ |
498,910 |
|
|
$ |
- |
|
|
$ |
- |
|
|
Held to maturity U.S. Treasury securities
|
|
|
249,621 |
|
|
|
240,032 |
|
|
|
240,032 |
|
|
|
- |
|
|
|
- |
|
|
Federal funds sold
|
|
|
6,052 |
|
|
|
6,052 |
|
|
|
- |
|
|
|
6,052 |
|
|
|
- |
|
|
Held to maturity debt securities
|
|
|
410,455 |
|
|
|
376,503 |
|
|
|
- |
|
|
|
376,003 |
|
|
|
500 |
|
|
Mortgage loans held for sale
|
|
|
11,744 |
|
|
|
11,744 |
|
|
|
- |
|
|
|
11,744 |
|
|
|
- |
|
|
Restricted equity securities
|
|
|
12,203 |
|
|
|
12,203 |
|
|
|
- |
|
|
|
12,203 |
|
|
|
- |
|
|
Loans, net
|
|
|
13,525,229 |
|
|
|
13,267,169 |
|
|
|
- |
|
|
|
- |
|
|
|
13,267,169 |
|
|
Financial Liabilities:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Deposits
|
|
$ |
14,219,034 |
|
|
$ |
14,217,711 |
|
|
$ |
- |
|
|
$ |
14,217,711 |
|
|
$ |
- |
|
|
Federal funds purchased
|
|
|
1,471,628 |
|
|
|
1,471,628 |
|
|
|
- |
|
|
|
1,471,628 |
|
|
|
- |
|
|
Other borrowings
|
|
|
34,750 |
|
|
|
31,258 |
|
|
|
- |
|
|
|
31,258 |
|
|
|
- |
|
|