Other Comprehensive Income (Loss) - Tax Effects of Components in Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Before Tax
Other comprehensive income (loss)	$ (75,450)	$ (12,487)
Tax Effect
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	21,014	9,605
After Tax
Total other comprehensive (loss)	(54,436)	(2,882)
Unrealized Gains (Losses) on Debt Securities Available for Sale
Before Tax
Other comprehensive income (loss), before reclassifications	(80,181)	(19,840)
Other comprehensive income (loss)	(80,185)	(19,844)
Tax Effect
Other comprehensive income (loss), before reclassifications	22,366	2,806
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	22,367	2,824
After Tax
Other comprehensive income (loss), before reclassifications	(57,815)	(17,034)
Total other comprehensive (loss)	(57,818)	(17,020)
AOCI, Accumulated Gain (Loss), Debt Securities Available-for-sale, Accretion of Unrealized Gains (Losses), Parent
Before Tax
Reclassification from AOCI, current period	(4)	(4)
Tax Effect
Reclassification from AOCI, current period	1	18
After Tax
Reclassification from AOCI, current period	(3)	14
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Before Tax
Other comprehensive income (loss), before reclassifications	4,382	5,832
Tax Effect
Other comprehensive income (loss), before reclassifications	(1,225)	(149)
After Tax
Other comprehensive income (loss), before reclassifications	3,157	5,683
Total other comprehensive (loss)	3,157	5,683
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent
Before Tax
Reclassification from AOCI, current period	(14)	(14)
Tax Effect
Reclassification from AOCI, current period	3	4
After Tax
Reclassification from AOCI, current period	(11)	(10)
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent
Before Tax
Reclassification from AOCI, current period	(339)	(1,511)
Tax Effect
Reclassification from AOCI, current period	95	422
After Tax
Reclassification from AOCI, current period	(244)	(1,089)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Before Tax
Other comprehensive income (loss), before reclassifications	706	3,050
Other comprehensive income (loss)	353	1,525
Tax Effect
Other comprehensive income (loss), before reclassifications	(226)	6,504
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(128)	6,930
After Tax
Other comprehensive income (loss), before reclassifications	480	9,554
Total other comprehensive (loss)	$ 225	$ 8,455