Other Noninterest Income (Loss) and Other Noninterest Expense - Summary of Other Noninterest Expense (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Income and Expenses [Abstract]
Client services		$ 15,944	$ 10,692	$ 8,181
Data processing services		7,316	8,079	7,895
Telephone		9,398	7,250	6,258
Postage and supplies		3,154	3,196	2,462
Dues and publications		2,476	2,549	1,745
Other		19,999	12,939	8,950
Total other noninterest expense	[1]	$ 58,287	$ 44,705	$ 35,491

[1] Prior period amounts have been revised to reflect the retrospective application of new accounting guidance adopted in the first quarter of 2015 related to our investments in qualified affordable housing projects (ASU 2014-01). See Note 2— "Summary of Significant Accounting Policies” of the “Notes to the Consolidated Financial Statements” under Part II, Item 8 of this report for additional details.