Other Comprehensive Income (Loss) - Changes in Components of OCI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total other comprehensive income (loss), pre-tax	$ 73,229	$ (264,687)	$ (47,635)
Total other comprehensive income (loss), tax expense (benefit)	18,448	(66,093)	(12,124)
Other comprehensive income (loss), net of tax	54,781	(198,594)	(35,511)
Securities available for sale:
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income gain (loss), before reclassifications, pre-tax	20,194	(285,829)	(51,470)
Other comprehensive income gain (loss) before reclassifications, tax expense (benefit)	5,066	(71,478)	(13,099)
Other comprehensive income gain (loss), before reclassifications, net of tax	15,128	(214,351)	(38,371)
Reclassification from AOCI, pre-tax	41,494		(2,170)
Reclassification from AOCI, tax expense (benefit)	10,431		(552)
Reclassification from AOCI, net of tax	31,063		(1,618)
Amortization of unrealized holding losses on securities transferred to held to maturity category, pre tax	13,557	4,964
Amortization of unrealized holding losses on securities transferred to held to maturity category, tax expense (benefit)	3,466	1,263
Amortization of unrealized holding losses on securities transferred to held to maturity category, net of tax	10,091	3,701
Total other comprehensive income (loss), pre-tax	75,245	(280,865)	(53,713)
Total other comprehensive income (loss), tax expense (benefit)	18,963	(70,215)	(13,670)
Other comprehensive income (loss), net of tax	56,282	(210,650)	(40,043)
Amortization of unrealized holding gains on securities transferred to the held to maturity category
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, pre-tax			(73)
Reclassification from AOCI, tax expense (benefit)			(19)
Reclassification from AOCI, net of tax			(54)
Derivative instruments:
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income gain (loss), before reclassifications, pre-tax	(2,558)	20,118	10,848
Other comprehensive income gain (loss) before reclassifications, tax expense (benefit)	(653)	5,125	2,761
Other comprehensive income gain (loss), before reclassifications, net of tax	(1,905)	14,993	8,087
Reclassification from AOCI, pre-tax			(4,676)
Reclassification from AOCI, tax expense (benefit)			(1,190)
Reclassification from AOCI, net of tax			(3,486)
Total other comprehensive income (loss), pre-tax	(2,558)	20,118	6,172
Total other comprehensive income (loss), tax expense (benefit)	(653)	5,125	1,571
Other comprehensive income (loss), net of tax	(1,905)	14,993	4,601
Net gain (loss) arising during the period
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income gain (loss), before reclassifications, pre-tax	80	(4,107)	(356)
Other comprehensive income gain (loss) before reclassifications, tax expense (benefit)	20	(1,045)	(92)
Other comprehensive income gain (loss), before reclassifications, net of tax	60	(3,062)	(264)
Amortization of net actuarial loss recognized in net periodic pension cost
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification from AOCI, pre-tax	462	167	262
Reclassification from AOCI, tax expense (benefit)	118	42	67
Reclassification from AOCI, net of tax	344	125	195
Total defined benefit pension and post-retirement benefit plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total other comprehensive income (loss), pre-tax	542	(3,940)	(94)
Total other comprehensive income (loss), tax expense (benefit)	138	(1,003)	(25)
Other comprehensive income (loss), net of tax	$ 404	$ (2,937)	$ (69)