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Derivative Financial Instruments - Forward Sales Commitments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Interest rate lock commitments \| Other assets
Derivative Financial Instruments
Notional amount	$ 25,373		$ 25,373		$ 45,004
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	496		496		1,201
Interest rate lock commitments \| Other liabilities
Derivative Financial Instruments
Notional amount	172		172		118
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	3		3		1
Forward sales commitments \| Other assets
Derivative Financial Instruments
Notional amount	172		172		978
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	3		3		32
Forward sales commitments \| Other liabilities
Derivative Financial Instruments
Notional amount	42,043		42,043		84,964
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	1,361		1,361		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)	(865)	$ (2,565)	(1,213)	$ (4,763)
Interest rate lock commitments and forward sales commitments \| Other assets \| Designated as hedging instrument
Derivative Financial Instruments
Notional amount	25,545		25,545		45,982
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	499		499		1,233
Interest rate lock commitments and forward sales commitments \| Other liabilities \| Designated as hedging instrument
Derivative Financial Instruments
Notional amount	42,215		42,215		85,082
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	1,364		1,364		$ 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	493	2,213	965	7,062
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)	$ (1,358)	$ (4,778)	$ (2,178)	$ (11,825)