Employee Benefits - Retirement plan contribution (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Employee Benefits
Retirement plan contributions	$ 5,080	$ 5,137	$ 5,126
Total ESOP shares outstanding	1,111,424	1,207,952	1,170,611
Salary Reduction Plan
Employee Benefits
Retirement plan contributions	$ 3,148	$ 3,123	$ 2,960
ESOP
Employee Benefits
Retirement plan contributions	$ 1,932	$ 2,014	$ 2,166