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Investment Securities - Schedule of Unrealized Loss on Investments (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Dec. 31, 2023
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Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | $ 47,802 | $ 62,124
Greater than or equal to 12 continuous months | 735,595 | 738,690
Total securities in a loss position | 783,397 | 800,814
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | (1,299) | (676)
Greater than or equal to 12 continuous months | (119,914) | (109,767)
Held-to-maturity, gross unrealized losses | (121,213) | (110,443)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 953 | 1,901
Available-for-sale, greater than 12 continuous months, fair value | 232,736 | 549,289
Available-for-sale, total securities in a loss position, fair value | 233,689 | 551,190
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (5) | (8)
Available-for-sale, greater than 12 continuous months, unrealized loss | (32,929) | (61,446)
Available-for-sale, total securities in a loss position, unrealized loss | (32,934) | (61,454)
Marketable Securities, Fair Value |  |
Marketable securities, less than 12 continuous months, fair value | 48,755 | 64,025
Marketable securities, greater than 12 continuous months, fair value | 968,331 | 1,287,979
Marketable securities, total securities in a loss position, fair value | 1,017,086 | 1,352,004
Marketable Securities, Continuous Unrealized Loss |  |
Marketable securities, less than 12 continuous months, unrealized loss | (1,304) | (684)
Marketable securities, greater than 12 continuous months, unrealized loss | (152,843) | (171,213)
Marketable securities, total securities in a loss position, unrealized loss | (154,147) | (171,897)
MBS pass-through securities issued by FHLMC, FNMA and GNMA |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 0 | 0
Greater than or equal to 12 continuous months | 246,943 | 261,865
Total securities in a loss position | 246,943 | 261,865
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | 0 | 0
Greater than or equal to 12 continuous months | (48,998) | (44,396)
Held-to-maturity, gross unrealized losses | (48,998) | (44,396)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 3 | 0
Available-for-sale, greater than 12 continuous months, fair value | 31,268 | 72,146
Available-for-sale, total securities in a loss position, fair value | 31,271 | 72,146
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 | (5,584) | (9,516)
Available-for-sale, total securities in a loss position, unrealized loss | (5,584) | (9,516)
CMOs issued by FHLMC |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 11,881 | 8,662
Greater than or equal to 12 continuous months | 183,398 | 188,657
Total securities in a loss position | 195,279 | 197,319
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | (196) | (21)
Greater than or equal to 12 continuous months | (27,144) | (24,848)
Held-to-maturity, gross unrealized losses | (27,340) | (24,869)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 950 | 1,235
Available-for-sale, greater than 12 continuous months, fair value | 78,117 | 240,414
Available-for-sale, total securities in a loss position, fair value | 79,067 | 241,649
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | (5) | (7)
Available-for-sale, greater than 12 continuous months, unrealized loss | (8,546) | (24,751)
Available-for-sale, total securities in a loss position, unrealized loss | (8,551) | (24,758)
CMOs issued by FNMA |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 15,552 | 42,474
Greater than or equal to 12 continuous months | 74,028 | 54,249
Total securities in a loss position | 89,580 | 96,723
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | (669) | (411)
Greater than or equal to 12 continuous months | (5,638) | (4,368)
Held-to-maturity, gross unrealized losses | (6,307) | (4,779)
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 | 3,866 | 21,272
Available-for-sale, total securities in a loss position, fair value | 3,866 | 21,272
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 | (654) | (2,715)
Available-for-sale, total securities in a loss position, unrealized loss | (654) | (2,715)
CMOs issued by GNMA |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 10,755 | 10,988
Greater than or equal to 12 continuous months | 34,003 | 34,783
Total securities in a loss position | 44,758 | 45,771
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | (363) | (244)
Greater than or equal to 12 continuous months | (5,317) | (4,991)
Held-to-maturity, gross unrealized losses | (5,680) | (5,235)
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 | 11,544 | 17,128
Available-for-sale, total securities in a loss position, fair value | 11,544 | 17,128
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 | (2,756) | (2,878)
Available-for-sale, total securities in a loss position, unrealized loss | (2,756) | (2,878)
SBA-backed securities |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 0 | 0
Greater than or equal to 12 continuous months | 1,560 | 1,763
Total securities in a loss position | 1,560 | 1,763
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | 0 | 0
Greater than or equal to 12 continuous months | (91) | (90)
Held-to-maturity, gross unrealized losses | (91) | (90)
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 | 335 | 19,471
Available-for-sale, total securities in a loss position, fair value | 335 | 19,471
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 | (31) | (1,655)
Available-for-sale, total securities in a loss position, unrealized loss | (31) | (1,655)
Debentures of government- sponsored agencies |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 0 | 0
Greater than or equal to 12 continuous months | 123,067 | 124,132
Total securities in a loss position | 123,067 | 124,132
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | 0 | 0
Greater than or equal to 12 continuous months | (23,209) | (21,994)
Held-to-maturity, gross unrealized losses | (23,209) | (21,994)
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 | 7,133 | 66,862
Available-for-sale, total securities in a loss position, fair value | 7,133 | 66,862
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 | (1,837) | (7,037)
Available-for-sale, total securities in a loss position, unrealized loss | (1,837) | (7,037)
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 | 10,570 | 10,623
Available-for-sale, total securities in a loss position, fair value | 10,570 | 10,623
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 | (1,362) | (1,300)
Available-for-sale, total securities in a loss position, unrealized loss | (1,362) | (1,300)
Obligations of state and political subdivisions |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 9,614 | 0
Greater than or equal to 12 continuous months | 43,793 | 44,437
Total securities in a loss position | 53,407 | 44,437
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | (71) | 0
Greater than or equal to 12 continuous months | (8,320) | (7,884)
Held-to-maturity, gross unrealized losses | (8,391) | (7,884)
Debt Securities, Available-For-Sale, Fair Value |  |
Available-for-sale, less than 12 continuous months, fair value | 0 | 666
Available-for-sale, greater than 12 continuous months, fair value | 84,481 | 90,655
Available-for-sale, total securities in a loss position, fair value | 84,481 | 91,321
Debt Securities, Available-for-sale, Unrealized Loss |  |
Available-for-sale, less than 12 continuous months, unrealized loss | 0 | (1)
Available-for-sale, greater than 12 continuous months, unrealized loss | (11,581) | (10,320)
Available-for-sale, total securities in a loss position, unrealized loss | (11,581) | (10,321)
Corporate bonds |  |
Debt Securities, Held-to-maturity, Fair Value |  |
Less than 12 continuous months | 0 | 0
Greater than or equal to 12 continuous months | 28,803 | 28,804
Total securities in a loss position | 28,803 | 28,804
Debt Securities, Held-to-maturity, Unrealized Loss |  |
Less than 12 continuous months | 0 | 0
Greater than or equal to 12 continuous months | (1,197) | (1,196)
Held-to-maturity, gross unrealized losses | (1,197) | (1,196)
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 | 5,422 | 10,718
Available-for-sale, total securities in a loss position, fair value | 5,422 | 10,718
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 | (578) | (1,274)
Available-for-sale, total securities in a loss position, unrealized loss | $ (578) | $ (1,274)

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