Other Comprehensive (Loss) Income - Schedule of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Pre Tax Amount
Total other comprehensive (loss) income	$ (27,193)	$ 355,835
Tax Benefit (Expense)
Total other comprehensive (loss) income	6,708	(95,285)
After Tax Amount
Before reclassifications	(20,912)	(26,378)
Less: reclassification adjustments	(427)	(286,928)
Total other comprehensive (loss) income	(20,485)	260,550
Unrealized (losses) gains on securities available for sale:
Pre Tax Amount
Before reclassifications	(23,581)	73,429
Less: reclassification adjustments	0	(269,638)
Total other comprehensive (loss) income	(23,581)	343,067
Tax Benefit (Expense)
Before reclassifications	5,711	(104,438)
Less: reclassification adjustments	0	(12,689)
Total other comprehensive (loss) income	5,711	(91,749)
After Tax Amount
Before reclassifications	(17,870)	(31,009)
Less: reclassification adjustments	0	(282,327)
Total other comprehensive (loss) income	(17,870)	251,318
Unrealized (losses) gains on cash flow hedges:
Pre Tax Amount
Before reclassifications	(4,202)	6,405
Less: reclassification adjustments	(2,777)	(7,933)
Total other comprehensive (loss) income	(1,425)	14,338
Tax Benefit (Expense)
Before reclassifications	1,160	(1,774)
Less: reclassification adjustments	767	2,197
Total other comprehensive (loss) income	393	(3,971)
After Tax Amount
Before reclassifications	(3,042)	4,631
Less: reclassification adjustments	(2,010)	(5,736)
Total other comprehensive (loss) income	(1,032)	10,367
Defined benefit pension plans:
Pre Tax Amount
Total other comprehensive (loss) income	(2,187)	(1,570)
Tax Benefit (Expense)
Total other comprehensive (loss) income	604	435
After Tax Amount
Before reclassifications	0	0
Less: reclassification adjustments	1,583	1,135
Total other comprehensive (loss) income	(1,583)	(1,135)
Change in actuarial net loss
Pre Tax Amount
Before reclassifications	0	0
Tax Benefit (Expense)
Before reclassifications	0	0
After Tax Amount
Before reclassifications	0	0
Less: amortization of actuarial net loss
Pre Tax Amount
Less: reclassification adjustments	(301)	(925)
Tax Benefit (Expense)
Less: reclassification adjustments	83	256
After Tax Amount
Less: reclassification adjustments	(218)	(669)
Less: accretion of prior service credit
Pre Tax Amount
Less: reclassification adjustments	2,488	2,495
Tax Benefit (Expense)
Less: reclassification adjustments	(687)	(691)
After Tax Amount
Less: reclassification adjustments	$ 1,801	$ 1,804

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