Derivative Financial Instruments - Forward Sales Commitments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Forward sales commitments
Derivative Financial Instruments
Notional amount	$ 231,400		$ 231,400		$ 135,300
Interest rate lock commitments and forward sales commitments
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Net gains (losses)	(20)	$ (278)	(952)	$ (60)
Interest rate lock commitments and forward sales commitments | Other assets
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	2,410		2,410		1,046
Interest rate lock commitments and forward sales commitments | Other liabilities
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	4,974		4,974		$ 2,187
Non-interest income | Interest rate lock commitments and forward sales commitments
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Gross gains	1,929	4,696	11,366	3,007
Non-interest expense | Interest rate lock commitments and forward sales commitments
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Gross (losses)	$ (1,949)	$ (4,974)	$ (12,318)	$ (3,067)