Other Assets - Summary of Other Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred tax asset, net	$ 33,091	$ 36,199
Prepaid expense	3,912	3,045
Software	1,563	2,039
Advanced compensation		249
Capital Trusts	1,706	1,702
Investment in Low Housing Tax Credit Funds	17,453	18,465
Life insurance proceeds receivable	2,242	2,120
Tax refund receivable		6,460
Premises held for sale		2,896
Due from broker	25,757
Miscellaneous other assets	1,212	1,568
Total other assets	$ 86,936	$ 74,743