Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 36,343	$ 37,338	$ 31,364	$ 20,374	$ 28,222	$ 27,422	$ 28,362	$ 33,649	$ 125,419	$ 117,655	$ 64,814
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) on available for sale securities arising during the period, after reclassifications									(204,376)	(13,788)	11,126
Change in minimum pension liability, after reclassifications									8,101	2,602	6,972
Change in joint beneficiary agreement liability									1,389	(113)	(596)
Other comprehensive income (loss)									(194,886)	(11,299)	17,502
Comprehensive income (loss)									$ (69,467)	$ 106,356	$ 82,316