Investments - Securities sales activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Proceeds from sales	$ 318,457	$ 288,986	$ 40,625
Gross gains on sales	1,009	2,346	748
Gross losses on sales	(4,881)	(2,263)	0
Net gains (losses) on sales of securities	(3,872)	83	748
Income tax expense (benefit) attributable to sales	$ (1,026)	$ (46)	$ 191