Noninterest Income and Expense - Summary of Noninterest Income and Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Noninterest income
Service charges on deposit accounts	$ 2,833	$ 2,626	$ 8,179	$ 7,483
Trust fees	1,083	967	3,143	2,764
Mortgage banking fees	1,135	2,138	3,873	4,962
Brokerage commissions and fees	444	351	1,264	1,079
Marine finance fees	194	137	1,213	597
Interchange income	3,119	2,582	9,137	7,747
BOLI income	1,078	836	3,200	2,326
Other income	2,453	1,844	7,497	4,895
Noninterest income, gross	12,339	11,481	37,506	31,853
Securities losses, net	(48)	(47)	(198)	(26)
TOTAL NONINTEREST INCOME (Note H)	12,291	11,434	37,308	31,827
Noninterest expense
Salaries and wages	17,129	15,627	48,939	49,371
Employee benefits	3,205	2,917	9,320	8,920
Outsourced data processing costs	3,493	3,231	10,565	9,956
Telephone/data lines	624	573	1,879	1,753
Occupancy	3,214	2,447	9,647	10,025
Furniture and equipment	1,367	1,191	4,292	4,261
Marketing	1,139	1,298	3,735	3,294
Legal and professional fees	2,019	2,560	6,293	7,968
FDIC assessments	431	548	1,624	1,768
Amortization of intangibles	1,004	839	2,997	2,397
Net (gain)/loss and disposition expense on other real estate owned	(136)	(297)	461	(293)
Other	3,910	3,427	13,057	11,312
Total	$ 37,399	$ 34,361	$ 112,809	$ 110,732