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Derivative Financial Instruments - Forward Sales Commitments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest rate lock commitments \| Other assets
Derivative Financial Instruments
Notional amount	$ 45,004	$ 67,965
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	1,201	1,032
Interest rate lock commitments \| Other liabilities
Derivative Financial Instruments
Notional amount	118	1,114
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	1	11
Forward sales commitments \| Other assets
Derivative Financial Instruments
Notional amount	978	1,773
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	32	14
Forward sales commitments \| Other liabilities
Derivative Financial Instruments
Notional amount	84,964	133,482
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	2,662	2,176
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)	(8,662)	(2,763)	$ (1,353)
Interest rate lock commitments and forward sales commitments \| Other assets \| Designated as hedging instrument
Derivative Financial Instruments
Notional amount		1,233
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	45,982	69,738
Interest rate lock commitments and forward sales commitments \| Other liabilities \| Designated as hedging instrument
Derivative Financial Instruments
Notional amount		2,663
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	85,082	134,596
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	9,667	3,988	1,757
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)	$ (18,329)	$ (6,751)	$ (3,110)