Fair Value Measurements - Fair Value Measurements at Reporting Date and Gain (Losses) from Fair Value Changes. (Details) - Non-Recurring - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually evaluated loans	$ 5,456	$ 22,171
Other real estate owned	46	88
Gain (losses) from fair value changes, Impaired loans	(7,107)	(1,855)
Gain (losses) from fair value changes, Other real estate owned	(8)	(35)
(Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually evaluated loans	0	0
Other real estate owned	0	0
(Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually evaluated loans		22,171
Other real estate owned	0	88
(Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually evaluated loans	5,456	0
Other real estate owned	$ 46	$ 0