Regulatory Capital - Reconciliation of Bank's Stockholders' Equity to Federal Regulatory Capital (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Banking and Thrift [Abstract]
Stockholders' equity of the Bank	$ 336,194	$ 216,030
Less: Disallowed servicing assets	0	(1,773)
Disallowed deferred tax assets	(69,254)	0
Accumulated other comprehensive loss	3,250	2,402
Common equity tier 1 capital	270,190
Additional tier 1 capital	0
Tier 1 capital	270,190	216,659
Plus: Allowable allowance for loan losses	20,426	16,373
Total risk-based capital	$ 290,616	$ 233,032