Other Comprehensive Income (Loss) - Tax Effects of Components in Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Before Tax
Other comprehensive income (loss)	$ (76,948)	$ 40,578	$ (152,398)	$ 28,090
Tax Effect
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	21,458	(11,338)	42,472	(1,732)
After Tax
Total other comprehensive (loss) income	(55,490)	29,240	(109,926)	26,358
Unrealized (Losses) on Debt Securities Available for Sale
Before Tax
Other comprehensive income (loss), before reclassifications	(52,246)	6,645	(132,429)	(13,196)
Other comprehensive income (loss)	(52,040)	6,347	(132,227)	(13,498)
Tax Effect
Other comprehensive income (loss), before reclassifications	14,570	(1,857)	36,938	950
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	14,513	(1,773)	36,882	1,052
After Tax
Other comprehensive income (loss), before reclassifications	(37,676)	4,788	(95,491)	(12,246)
Total other comprehensive (loss) income	(37,527)	4,574	(95,345)	(12,446)
AOCI, Accumulated Gain (Loss), Debt Securities Available-for-sale, Accretion of Unrealized Gains (Losses), Parent
Before Tax
Reclassification from AOCI, current period	(4)	(17)	(8)	(21)
Tax Effect
Reclassification from AOCI, current period	1	5	2	23
After Tax
Reclassification from AOCI, current period	(3)	(12)	(6)	2
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Other Reclassifications, Parent
Before Tax
Reclassification from AOCI, current period	210	(281)	210	(281)
Tax Effect
Reclassification from AOCI, current period	(58)	79	(58)	79
After Tax
Reclassification from AOCI, current period	152	(202)	152	(202)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Before Tax
Other comprehensive income (loss), before reclassifications	1,149	1,315	5,532	7,147
Tax Effect
Other comprehensive income (loss), before reclassifications	(321)	(367)	(1,547)	(516)
After Tax
Other comprehensive income (loss), before reclassifications	828	948	3,985	6,631
Total other comprehensive (loss) income	828	948	3,985	6,631
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent
Before Tax
Reclassification from AOCI, current period	(14)	(14)	(28)	(28)
Tax Effect
Reclassification from AOCI, current period	3	3	6	8
After Tax
Reclassification from AOCI, current period	(11)	(11)	(22)	(20)
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent
Before Tax
Reclassification from AOCI, current period	(339)	(1,511)	(678)	(3,022)
Tax Effect
Reclassification from AOCI, current period	95	422	190	844
After Tax
Reclassification from AOCI, current period	(244)	(1,089)	(488)	(2,178)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Before Tax
Other comprehensive income (loss), before reclassifications	(25,704)	34,441	(24,997)	37,491
Other comprehensive income (loss)	(26,057)	32,916	(25,703)	34,441
Tax Effect
Other comprehensive income (loss), before reclassifications	7,168	(9,623)	6,941	(3,120)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	7,266	(9,198)	7,137	(2,268)
After Tax
Other comprehensive income (loss), before reclassifications	(18,536)	24,818	(18,056)	34,371
Total other comprehensive (loss) income	$ (18,791)	$ 23,718	$ (18,566)	$ 32,173