Fair Value - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Outstanding balances in collateral dependent related to allowance for credit losses	$ 41,200		$ 41,200
Collateral dependent related to allowance for credit losses	4,600		4,600
Outstanding balances in impaired loans					$ 41,200
Impaired loans, related allowance					5,500
Foreclosed assets remeasured after initial recognition			7,600	$ 12,000
Write-downs of allowance for foreclosed assets after initial recognition			1,600	1,400
Noninterest gain (loss) Mortgage banking, net for changes in fair value of LHFS	4,100	$ (544)	11,300	2,300
Interest earned on LHFS included in Interest and fees on LHFS and LHFI	2,000	$ 1,700	4,800	$ 4,100
GNMA optional repurchase loans	$ 147,400		$ 147,400		$ 57,100