Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Trust fees	$ 4,680	$ 3,631
Brokerage and insurance commissions	907	1,036
Total noninterest income	15,666	14,124
Loan servicing income	1,754	1,724
Securities gains, net	1,441	2,482
Unrealized loss on equity securities, net	(28)	0
Net gains on sale of loans held for sale	4,051	6,147
Valuation adjustment on commercial servicing rights	(2)	5
Income on bank owned life insurance	614	617
Other noninterest income	1,220	794
Total noninterest income out-of-scope of Topic 606	9,050	11,769
TOTAL NONINTEREST INCOME	24,716	25,893
Service charges and fees on deposit accounts
Disaggregation of Revenue [Line Items]
Total noninterest income	2,618	2,160
Overdraft fees
Disaggregation of Revenue [Line Items]
Total noninterest income	2,208	2,193
Customer service fees
Disaggregation of Revenue [Line Items]
Total noninterest income	77	49
Credit card fee income
Disaggregation of Revenue [Line Items]
Total noninterest income	2,190	2,033
Debit card income
Disaggregation of Revenue [Line Items]
Total noninterest income	2,985	3,021
Other service charges
Disaggregation of Revenue [Line Items]
Total noninterest income	1	1
Total service charges and fees
Disaggregation of Revenue [Line Items]
Total noninterest income	$ 10,079	$ 9,457