Loans - Loans Sales (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total net gains on loan sales		$ 1,625	$ 1,414
Corporate loan sales
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales		8,321	15,368
Less book value of loans sold		8,123	15,117
Total net gains on loan sales	[1]	198	251
1-4 family mortgage loan sales
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sales		65,185	55,761
Less book value of loans sold		63,758	54,598
Total net gains on loan sales	[2]	$ 1,427	$ 1,163

[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.