Quarterly report pursuant to Section 13 or 15(d)

Note 4 - Securities - Investment Securities Continuous Unrealized Loss Position (Details)

v3.23.3
Note 4 - Securities - Investment Securities Continuous Unrealized Loss Position (Details) - USD ($)
$ in Thousands
Sep. 30, 2023
Dec. 31, 2022
Debt securities available for sale, less than twelve months, gross unrealized losses $ (901) $ (22,258)
Debt securities available for sale, less than twelve months, fair value 246,157 372,749
Debt Securities Available for Sale, Twelve Months or More, Gross Unrealized Losses (84,548) (40,309)
Debt Securities, Available for Sale, Twelve Months or More, Fair Value 530,197 260,400
Debt Securities, Available for Sale, Gross Unrealized Losses (85,449) (62,567)
Debt Securities, Available for Sale, Fair Value 776,354 633,149
Debt Securities held to maturity less than twelve months, gross unrealized losses (44) (44,573)
Debt securities, held to maturity, Less Than Twelve Months, Fair Value 50,515 578,572
Debt Securities Held To Maturity, Twelve Months or More, Gross Unrealized Losses (110,849) (53,603)
U.S. Treasury Securities 878,920 352,742
Debt Securities, Held To Maturity , Gross Unrealized Losses (110,893) (98,175)
Debt Securities,Held To Maturity, Fair Value 929,434 931,314
US Treasury Securities [Member]    
Debt securities available for sale, less than twelve months, gross unrealized losses (96) (33)
Debt securities available for sale, less than twelve months, fair value 231,360 2,969
Debt Securities Available for Sale, Twelve Months or More, Gross Unrealized Losses 0 0
Debt Securities, Available for Sale, Twelve Months or More, Fair Value 0 0
Debt Securities, Available for Sale, Gross Unrealized Losses (96) (33)
Debt Securities, Available for Sale, Fair Value 231,360 2,969
Debt Securities held to maturity less than twelve months, gross unrealized losses (6) (12,662)
Debt securities, held to maturity, Less Than Twelve Months, Fair Value 49,669 295,383
Debt Securities Held To Maturity, Twelve Months or More, Gross Unrealized Losses (35,008) (23,537)
U.S. Treasury Securities 473,513 175,570
Debt Securities, Held To Maturity , Gross Unrealized Losses (35,014) (36,197)
Debt Securities,Held To Maturity, Fair Value 523,182 470,953
Collateralized Mortgage-Backed Securities [Member]    
Debt securities available for sale, less than twelve months, gross unrealized losses (33) (3,473)
Debt securities available for sale, less than twelve months, fair value 1,137 60,234
Debt Securities Available for Sale, Twelve Months or More, Gross Unrealized Losses (35,727) (29,309)
Debt Securities, Available for Sale, Twelve Months or More, Fair Value 214,104 189,109
Debt Securities, Available for Sale, Gross Unrealized Losses (35,760) (32,782)
Debt Securities, Available for Sale, Fair Value 215,241 249,343
Debt Securities held to maturity less than twelve months, gross unrealized losses (38) (31,367)
Debt securities, held to maturity, Less Than Twelve Months, Fair Value 846 278,746
Debt Securities Held To Maturity, Twelve Months or More, Gross Unrealized Losses (74,890) (29,592)
U.S. Treasury Securities 398,551 174,842
Debt Securities, Held To Maturity , Gross Unrealized Losses (74,928) (60,960)
Debt Securities,Held To Maturity, Fair Value 399,396 453,588
US States and Political Subdivisions Debt Securities [Member]    
Debt securities available for sale, less than twelve months, gross unrealized losses 0 (186)
Debt securities available for sale, less than twelve months, fair value 0 5,283
Debt Securities Available for Sale, Twelve Months or More, Gross Unrealized Losses (1,570) (1,411)
Debt Securities, Available for Sale, Twelve Months or More, Fair Value 10,462 7,880
Debt Securities, Available for Sale, Gross Unrealized Losses (1,570) (1,597)
Debt Securities, Available for Sale, Fair Value 10,462 13,163
Debt Securities held to maturity less than twelve months, gross unrealized losses 0 (544)
Debt securities, held to maturity, Less Than Twelve Months, Fair Value 0 4,443
Debt Securities Held To Maturity, Twelve Months or More, Gross Unrealized Losses (951) (474)
U.S. Treasury Securities 6,856 2,330
Debt Securities, Held To Maturity , Gross Unrealized Losses (951) (1,018)
Debt Securities,Held To Maturity, Fair Value 6,856 6,773
Corporate Debt Securities [Member]    
Debt securities available for sale, less than twelve months, gross unrealized losses (772) (18,566)
Debt securities available for sale, less than twelve months, fair value 13,660 304,254
Debt Securities Available for Sale, Twelve Months or More, Gross Unrealized Losses (47,251) (9,589)
Debt Securities, Available for Sale, Twelve Months or More, Fair Value 305,631 63,411
Debt Securities, Available for Sale, Gross Unrealized Losses (48,023) (28,155)
Debt Securities, Available for Sale, Fair Value $ 319,291 367,666
US Government Agencies Debt Securities [Member]    
Debt securities available for sale, less than twelve months, gross unrealized losses   0
Debt securities available for sale, less than twelve months, fair value   9
Debt Securities Available for Sale, Twelve Months or More, Gross Unrealized Losses   0
Debt Securities, Available for Sale, Twelve Months or More, Fair Value   0
Debt Securities, Available for Sale, Gross Unrealized Losses   0
Debt Securities, Available for Sale, Fair Value   $ 9