Fair Value Measurement - Schedule of Gains and Losses from Nonrecurring Fair Value Adjustments (Detail) - Fair Value Nonrecurring Basis [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
(Gains)/losses from nonrecurring fair value adjustments	$ 431	$ 184	$ 316	$ (88)	$ (762)
Impaired Originated & PNCI Loans [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
(Gains)/losses from nonrecurring fair value adjustments	$ 431	(22)	$ 316	151	(660)
Foreclosed Assets [Member]
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
(Gains)/losses from nonrecurring fair value adjustments		$ 206		$ (239)	$ (102)