Accumulated Other Comprehensive (Loss) Income - Schedule of Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 1,230,575	$ 893,421	$ 852,401
Other comprehensive (loss) income before reclassifications	(316,783)	(40,729)	14,879
Amounts reclassified from accumulated other comprehensive income	(222)	1,409	(5,652)
Net current-period other comprehensive income (loss)	(317,005)	(39,320)	9,227
Ending balance	1,031,596	1,230,575	893,421
Unrealized Gain (Loss) on Securities Available for Sale
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(24,698)	15,749	7,504
Other comprehensive (loss) income before reclassifications	(317,319)	(41,400)	14,425
Amounts reclassified from accumulated other comprehensive income	0	953	(6,180)
Net current-period other comprehensive income (loss)	(317,319)	(40,447)	8,245
Ending balance	(342,017)	(24,698)	15,749
Postretirement Plans (Liability) Asset
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(272)	(1,399)	(2,381)
Other comprehensive (loss) income before reclassifications	536	671	454
Amounts reclassified from accumulated other comprehensive income	(222)	456	528
Net current-period other comprehensive income (loss)	314	1,127	982
Ending balance	42	(272)	(1,399)
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(24,970)	14,350	5,123
Ending balance	$ (341,975)	$ (24,970)	$ 14,350