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Investment Securities - Schedule of Unrealized Loss on Investments (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
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Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | $ 60,224 | $ 359,313
Greater than or equal to 12 continuous months | 704,750 | 459,948
Total securities in a loss position | 764,974 | 819,261
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | (2,678) | (23,733)
Greater than or equal to 12 continuous months | (149,474) | (103,305)
Held-to-maturity, gross unrealized losses | (152,152) | (127,038)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 1,196 | 354,695
Available-for-sale, greater than 12 continuous months, fair value | 657,206 | 443,274
Available-for-sale, total securities in a loss position, fair value | 658,402 | 797,969
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (36) | (33,887)
Available-for-sale, greater than 12 continuous months, unrealized loss | (96,189) | (56,656)
Available-for-sale, total securities in a loss position, unrealized loss | (96,225) | (90,543)
Marketable Securities, Fair Value |  |
Marketable securities, less than 12 continuous months, fair value | 61,420 | 714,008
Marketable securities, greater than 12 continuous months, fair value | 1,361,956 | 903,222
Marketable securities, total securities in a loss position, fair value | 1,423,376 | 1,617,230
Marketable Securities, Continuous Unrealized Loss |  |
Marketable securities, less than 12 continuous months, unrealized loss | (2,714) | (57,620)
Marketable securities, greater than 12 continuous months, unrealized loss | (245,663) | (159,961)
Marketable securities, total securities in a loss position, unrealized loss | (248,377) | (217,581)
MBS pass-through securities issued by FHLMC, FNMA and GNMA |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 0 | 62,627
Greater than or equal to 12 continuous months | 249,726 | 218,507
Total securities in a loss position | 249,726 | 281,134
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | 0 | (5,960)
Greater than or equal to 12 continuous months | (61,870) | (44,187)
Held-to-maturity, gross unrealized losses | (61,870) | (50,147)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 0 | 44,630
Available-for-sale, greater than 12 continuous months, fair value | 70,980 | 52,235
Available-for-sale, total securities in a loss position, fair value | 70,980 | 96,865
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | 0 | (4,501)
Available-for-sale, greater than 12 continuous months, unrealized loss | (13,263) | (7,632)
Available-for-sale, total securities in a loss position, unrealized loss | (13,263) | (12,133)
CMOs issued by FHLMC |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 4,311 | 78,144
Greater than or equal to 12 continuous months | 181,530 | 113,796
Total securities in a loss position | 185,841 | 191,940
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | (68) | (5,874)
Greater than or equal to 12 continuous months | (33,380) | (23,629)
Held-to-maturity, gross unrealized losses | (33,448) | (29,503)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 0 | 169,760
Available-for-sale, greater than 12 continuous months, fair value | 269,883 | 143,995
Available-for-sale, total securities in a loss position, fair value | 269,883 | 313,755
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | 0 | (15,144)
Available-for-sale, greater than 12 continuous months, unrealized loss | (37,236) | (18,538)
Available-for-sale, total securities in a loss position, unrealized loss | (37,236) | (33,682)
CMOs issued by FNMA |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 41,398 | 106,485
Greater than or equal to 12 continuous months | 53,508 | 0
Total securities in a loss position | 94,906 | 106,485
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | (2,413) | (5,419)
Greater than or equal to 12 continuous months | (6,712) | 0
Held-to-maturity, gross unrealized losses | (9,125) | (5,419)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 0 | 4,790
Available-for-sale, greater than 12 continuous months, fair value | 26,820 | 27,529
Available-for-sale, total securities in a loss position, fair value | 26,820 | 32,319
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | 0 | (235)
Available-for-sale, greater than 12 continuous months, unrealized loss | (4,012) | (3,617)
Available-for-sale, total securities in a loss position, unrealized loss | (4,012) | (3,852)
CMOs issued by GNMA |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 11,481 | 27,570
Greater than or equal to 12 continuous months | 25,859 | 10,331
Total securities in a loss position | 37,340 | 37,901
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | (154) | (1,676)
Greater than or equal to 12 continuous months | (4,662) | (1,400)
Held-to-maturity, gross unrealized losses | (4,816) | (3,076)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 0 | 8,214
Available-for-sale, greater than 12 continuous months, fair value | 16,837 | 23,612
Available-for-sale, total securities in a loss position, fair value | 16,837 | 31,826
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | 0 | (374)
Available-for-sale, greater than 12 continuous months, unrealized loss | (3,668) | (2,922)
Available-for-sale, total securities in a loss position, unrealized loss | (3,668) | (3,296)
SBA-backed securities |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 0 | 2,239
Greater than or equal to 12 continuous months | 1,713 | 0
Total securities in a loss position | 1,713 | 2,239
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | 0 | (133)
Greater than or equal to 12 continuous months | (140) | 0
Held-to-maturity, gross unrealized losses | (140) | (133)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 0 | 37,845
Available-for-sale, greater than 12 continuous months, fair value | 28,223 | 6,133
Available-for-sale, total securities in a loss position, fair value | 28,223 | 43,978
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | 0 | (3,228)
Available-for-sale, greater than 12 continuous months, unrealized loss | (3,166) | (143)
Available-for-sale, total securities in a loss position, unrealized loss | (3,166) | (3,371)
Debentures of government- sponsored agencies |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 0 | 38,645
Greater than or equal to 12 continuous months | 117,157 | 80,711
Total securities in a loss position | 117,157 | 119,356
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | 0 | (2,530)
Greater than or equal to 12 continuous months | (28,893) | (23,937)
Held-to-maturity, gross unrealized losses | (28,893) | (26,467)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 0 | 19,054
Available-for-sale, greater than 12 continuous months, fair value | 117,166 | 116,052
Available-for-sale, total securities in a loss position, fair value | 117,166 | 135,106
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | 0 | (946)
Available-for-sale, greater than 12 continuous months, unrealized loss | (11,971) | (13,062)
Available-for-sale, total securities in a loss position, unrealized loss | (11,971) | (14,008)
U.S. Treasury securities |  |
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 0 | 0
Available-for-sale, greater than 12 continuous months, fair value | 10,215 | 10,269
Available-for-sale, total securities in a loss position, fair value | 10,215 | 10,269
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | 0 | 0
Available-for-sale, greater than 12 continuous months, unrealized loss | (1,703) | (1,635)
Available-for-sale, total securities in a loss position, unrealized loss | (1,703) | (1,635)
Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 3,034 | 15,155
Greater than or equal to 12 continuous months | 47,051 | 36,603
Total securities in a loss position | 50,085 | 51,758
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | (43) | (589)
Greater than or equal to 12 continuous months | (12,023) | (10,152)
Held-to-maturity, gross unrealized losses | (12,066) | (10,741)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 1,196 | 70,402
Available-for-sale, greater than 12 continuous months, fair value | 82,526 | 28,711
Available-for-sale, total securities in a loss position, fair value | 83,722 | 99,113
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (36) | (9,459)
Available-for-sale, greater than 12 continuous months, unrealized loss | (18,735) | (5,302)
Available-for-sale, total securities in a loss position, unrealized loss | (18,771) | (14,761)
Corporate bonds |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 0 | 28,448
Greater than or equal to 12 continuous months | 28,206 | 0
Total securities in a loss position | 28,206 | 28,448
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | 0 | (1,552)
Greater than or equal to 12 continuous months | (1,794) | 0
Held-to-maturity, gross unrealized losses | (1,794) | (1,552)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 0 | 0
Available-for-sale, greater than 12 continuous months, fair value | 34,556 | 33,276
Available-for-sale, total securities in a loss position, fair value | 34,556 | 33,276
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | 0 | 0
Available-for-sale, greater than 12 continuous months, unrealized loss | (2,435) | (3,714)
Available-for-sale, total securities in a loss position, unrealized loss | (2,435) | (3,714)
Asset-backed securities |  |
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 0 | 0
Available-for-sale, greater than 12 continuous months, fair value | 0 | 1,462
Available-for-sale, total securities in a loss position, fair value | 0 | 1,462
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | 0 | 0
Available-for-sale, greater than 12 continuous months, unrealized loss | 0 | (91)
Available-for-sale, total securities in a loss position, unrealized loss | $ 0 | $ (91)

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