XML 54 R44.htm IDEA: XBRL DOCUMENT v3.23.1
Note 6 - Debt Securities - Securities Available-for-sale Continuous Unrealized Loss Position (Details) - USD ($)
$ in Thousands
Mar. 31, 2023
Dec. 31, 2022
Less than 12 months, estimated fair value $ 139,368 $ 406,076
Less than 12 months, unrealized losses (4,240) (31,483)
12 months or more, estimated fair value 629,220 367,850
12 months or more, unrealized losses (66,582) (52,117)
Total estimated fair value 768,588 773,926
Total unrealized losses (70,822) (83,600)
US Treasury Securities [Member]    
Less than 12 months, estimated fair value 15,058 57,882
Less than 12 months, unrealized losses (403) (3,960)
12 months or more, estimated fair value 190,455 147,215
12 months or more, unrealized losses (16,143) (15,508)
Total estimated fair value 205,513 205,097
Total unrealized losses (16,546) (19,468)
US Government Agencies Debt Securities [Member]    
Less than 12 months, estimated fair value 16,815 61,821
Less than 12 months, unrealized losses (341) (4,293)
12 months or more, estimated fair value 85,231 38,492
12 months or more, unrealized losses (7,439) (5,148)
Total estimated fair value 102,046 100,313
Total unrealized losses (7,780) (9,441)
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]    
Less than 12 months, estimated fair value 9,232 45,440
Less than 12 months, unrealized losses (456) (4,393)
12 months or more, estimated fair value 104,381 70,854
12 months or more, unrealized losses (14,361) (12,075)
Total estimated fair value 113,613 116,294
Total unrealized losses (14,817) (16,468)
US States and Political Subdivisions Debt Securities [Member]    
Less than 12 months, estimated fair value 65,599 181,640
Less than 12 months, unrealized losses (1,727) (14,556)
12 months or more, estimated fair value 209,541 97,907
12 months or more, unrealized losses (23,860) (16,647)
Total estimated fair value 275,140 279,547
Total unrealized losses (25,587) (31,203)
Corporate Debt Securities [Member]    
Less than 12 months, estimated fair value 32,664 59,293
Less than 12 months, unrealized losses (1,313) (4,281)
12 months or more, estimated fair value 39,612 13,382
12 months or more, unrealized losses (4,779) (2,739)
Total estimated fair value 72,276 72,675
Total unrealized losses $ (6,092) $ (7,020)