Accumulated Other Comprehensive Income - Unrealized gains (losses) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ (139,974)	$ (2,426)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	14,385	(68,599)
Ending balance	(125,589)	(71,025)
Unrealized gains and (Losses) on available- for-sale Securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(128,896)	15,674
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	14,238	(68,914)
Ending balance	(114,658)	(53,240)
Unrealized gains (losses) on securities available-for-sale with other than temporary impairment
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	2,239	2,519
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(53)	129
Ending balance	2,186	2,648
Unrealized gains (losses) on securities available-for-sale without other than temporary impairment
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(131,135)	13,155
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	14,291	(69,043)
Ending balance	(116,844)	(55,888)
Retirement plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(11,078)	(18,100)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	147	315
Ending balance	$ (10,931)	$ (17,785)