Other Noninterest Income and Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Income and Expenses [Abstract]
Reporting threshold for other income and operating expenses (percent, greater than)	1.00%
NONINTEREST INCOME
Other service charges	$ 2,982	$ 2,671	$ 2,972
Increase in cash surrender value of corporate owned life insurance	2,196	2,106	2,064
Net gain on sale of loans	50	95	54
Other miscellaneous income	2,403	1,419	3,788
Total other noninterest income	7,631	6,291	8,878
NONINTEREST EXPENSES
Marketing expense	5,013	5,087	4,780
Professional fees	5,725	5,446	5,352
Technology expense	8,332	7,011	6,220
Cardholder expense	3,391	2,503	2,653
Other miscellaneous expenses	20,483	17,029	18,662
Total other noninterest expenses	$ 42,944	$ 37,076	$ 37,667