Other Comprehensive Income - Schedule of Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Pre Tax Amount
Total other comprehensive loss	$ (13,365)	$ 32,252	$ (40,558)	$ 388,087
Tax (Expense) Benefit
Total other comprehensive loss	3,416	(8,000)	10,124	(103,285)
After Tax Amount
Before reclassifications			(30,879)	13,131
Less: reclassification adjustments			(445)	(271,671)
Total other comprehensive (loss) income	(9,949)	24,252	(30,434)	284,802
Unrealized gains (losses) on securities available for sale:
Pre Tax Amount
Before reclassifications	(11,495)	26,211	(35,076)	99,640
Less: reclassification adjustments	0	0	0	(269,638)
Total other comprehensive loss	(11,495)	26,211	(35,076)	369,278
Tax (Expense) Benefit
Before reclassifications	2,899	13,610	8,610	(90,828)
Less: reclassification adjustments	0	19,936	0	7,247
Total other comprehensive loss	2,899	(6,326)	8,610	(98,075)
After Tax Amount
Before reclassifications	(8,596)	39,821	(26,466)	8,812
Less: reclassification adjustments	0	19,936	0	(262,391)
Total other comprehensive (loss) income	(8,596)	19,885	(26,466)	271,203
Unrealized gains (losses) on cash flow hedges:
Pre Tax Amount
Before reclassifications	(1,894)	(432)	(6,096)	5,973
Less: reclassification adjustments	(2,212)	(7,981)	(4,989)	(15,914)
Total other comprehensive loss	318	7,549	(1,107)	21,887
Tax (Expense) Benefit
Before reclassifications	523	120	1,683	(1,654)
Less: reclassification adjustments	610	2,211	1,377	4,408
Total other comprehensive loss	(87)	(2,091)	306	(6,062)
After Tax Amount
Before reclassifications	(1,371)	(312)	(4,413)	4,319
Less: reclassification adjustments	(1,602)	(5,770)	(3,612)	(11,506)
Total other comprehensive (loss) income	231	5,458	(801)	15,825
Defined benefit pension plans:
Pre Tax Amount
Total other comprehensive loss	(2,188)	(1,508)	(4,375)	(3,078)
Tax (Expense) Benefit
Total other comprehensive loss	604	417	1,208	852
After Tax Amount
Before reclassifications			0	0
Less: reclassification adjustments			3,167	2,226
Total other comprehensive (loss) income	(1,584)	(1,091)	(3,167)	(2,226)
Change in actuarial net loss
Pre Tax Amount
Before reclassifications	0	0	0	0
Tax (Expense) Benefit
Before reclassifications	0	0	0	0
After Tax Amount
Before reclassifications	0	0	0	0
Less: amortization of actuarial net loss
Pre Tax Amount
Less: reclassification adjustments	(301)	(980)	(602)	(1,905)
Tax (Expense) Benefit
Less: reclassification adjustments	83	272	166	528
After Tax Amount
Less: reclassification adjustments	(218)	(708)	(436)	(1,377)
Less: accretion of prior service credit
Pre Tax Amount
Less: reclassification adjustments	2,489	2,488	4,977	4,983
Tax (Expense) Benefit
Less: reclassification adjustments	(687)	(689)	(1,374)	(1,380)
After Tax Amount
Less: reclassification adjustments	$ 1,802	$ 1,799	$ 3,603	$ 3,603

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