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Derivative Financial Instruments - Forward Sales Commitments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Interest rate lock commitments \| Other assets
Derivative Financial Instruments
Notional amount	$ 31,480		$ 31,480		$ 45,004
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	538		538		1,201
Interest rate lock commitments \| Other liabilities
Derivative Financial Instruments
Notional amount	117		117		118
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	1		1		1
Forward sales commitments \| Other assets
Derivative Financial Instruments
Notional amount	117		117		978
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	1		1		32
Forward sales commitments \| Other liabilities
Derivative Financial Instruments
Notional amount	49,418		49,418		84,964
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	1,439		1,439		2,662
Interest rate lock commitments and forward sales commitments \| Designated as hedging instrument
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Net gains (losses)	(901)	$ (2,469)	(2,114)	$ (7,232)
Interest rate lock commitments and forward sales commitments \| Other assets \| Designated as hedging instrument
Derivative Financial Instruments
Notional amount	31,597		31,597		45,982
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	539		539		1,233
Interest rate lock commitments and forward sales commitments \| Other liabilities \| Designated as hedging instrument
Derivative Financial Instruments
Notional amount	49,535		49,535		85,082
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	1,440		1,440		$ 2,663
Mortgage revenue \| Interest rate lock commitments \| Designated as hedging instrument
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Gross gains	537	1,405	1,502	8,467
Mortgage revenue \| Forward sales commitments \| Designated as hedging instrument
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Gross (losses)	$ (1,438)	$ (3,874)	$ (3,616)	$ (15,699)