Other Noninterest Income and Other Noninterest Expense - Summary of Other Noninterest Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Other Income and Expenses [Abstract]
Lending and other client related processing costs	$ 5,885	$ 3,608	$ 13,721	$ 10,861
Telephone	2,460	2,224	7,109	6,727
Data processing services	2,137	2,083	6,353	5,274
Dues and publications	809	521	2,258	1,803
Postage and supplies	598	728	2,172	2,220
Other	3,644	5,106	12,679	15,216
Total other noninterest expense	$ 15,533	$ 14,270	$ 44,292	$ 42,101