Loans - Loans Sales (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total net gains on loan sales		$ 1,509	$ 1,879	$ 3,134	$ 3,293
Corporate loan sales
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales		3,991	19,569	12,312	34,937
Less book value of loans sold		3,861	19,123	11,984	34,240
Total net gains on loan sales	[1]	130	446	328	697
1-4 family mortgage loan sales
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales		65,715	60,894	130,900	116,655
Less book value of loans sold		64,336	59,461	128,094	114,059
Total net gains on loan sales	[2]	$ 1,379	$ 1,433	$ 2,806	$ 2,596

[1] Net gains on corporate loan sales are included in other service charges, commissions, and fees in the Condensed Consolidated Statements of Income.

[2] Net gains on 1-4 family mortgage loan sales are included in mortgage banking income in the Condensed Consolidated Statements of Income.