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Accumulated Other Comprehensive Income (Loss) - Schedule of AOCI (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Beginning Balance | $ 6,340,350 | $ 5,562,900 | $ 5,128,595
Other comprehensive income (loss) before reclassifications | 247,726 | (33,638) | 38,379
Amounts reclassified from AOCI to income | 19,646 | 26,404 | 9,234
Ending Balance | 8,494,788 | 6,340,350 | 5,562,900
Accumulated Other Comprehensive Income (Loss) |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Beginning Balance | (746,043) | (738,809) | (786,422)
Ending Balance | (478,671) | (746,043) | (738,809)
Unrealized Gains and Losses on Available-for-Sale Debt Securities |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Beginning Balance | (668,063) | (652,518) | (642,346)
Other comprehensive income (loss) before reclassifications | 239,600 | (15,702) | (14,817)
Amounts reclassified from AOCI to income | 27 | 157 | 4,645
Ending Balance | (428,436) | (668,063) | (652,518)
Unrecognized Gains and Losses on Held-to-Maturity Securities |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Beginning Balance | (82,294) | (95,472) | (112,664)
Other comprehensive income (loss) before reclassifications | 0 | 0 | 1,325
Amounts reclassified from AOCI to income | 11,830 | 13,178 | 15,867
Ending Balance | (70,464) | (82,294) | (95,472)
Gains and Losses on Hedges |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Beginning Balance | 4,314 | 9,181 | (31,549)
Other comprehensive income (loss) before reclassifications | 8,126 | (17,936) | 51,871
Amounts reclassified from AOCI to income | 7,789 | 13,069 | (11,141)
Ending Balance | 20,229 | 4,314 | 9,181
Defined Benefit Pension Plans |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Beginning Balance | 0 | 0 | 137
Other comprehensive income (loss) before reclassifications | 0 | 0 | 0
Amounts reclassified from AOCI to income |  |  | (137)
Ending Balance | $ 0 | $ 0 | $ 0

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-14A Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 55 -Paragraph 15 -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482739/220-10-55-15 + Details
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