Fair Value - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Nonfinancial Assets and Liabilities [Abstract]
Outstanding balances in impaired loans	$ 55,800	$ 48,900
Impaired loans, related allowance	6,400	1,700
Foreclosed assets re-measured after initial recognition	19,200	26,600
Write-downs of allowance for foreclosed assets after initial recognition	873	3,300
Noninterest gain (loss) Mortgage banking, net for changes in fair value of LHFS	1,400	3,000	$ (2,500)
Interest earned on LHFS included in Interest and fees on LHFS and LHFI	4,900	4,900	$ 5,000
GNMA optional repurchase loans	$ 61,600	$ 48,200