FDIC Indemnification Asset - Additional Information (Detail) $ in Thousands		3 Months Ended
	Jul. 16, 2010	Mar. 31, 2016 USD ($) agreement	Mar. 31, 2015 USD ($)
FDIC Indemnification Asset [Line Items]
Percentage future credit losses and workout expenses to be absorbed by FDIC		80.00%
Payment to FDIC as consideration for the early termination of loss share agreements | $		$ 3,029	$ 0
Contract termination expense | $		$ (9,178)	$ 0
Single Family Loans
FDIC Indemnification Asset [Line Items]
Number of FDIC loss sharing agreements | agreement		3
Period covered by loss sharing agreement	10 years
Commercial and Other Loans
FDIC Indemnification Asset [Line Items]
Number of FDIC loss sharing agreements | agreement		3
Period covered by loss sharing agreement	5 years
Other Covered Assets
FDIC Indemnification Asset [Line Items]
Period covered by loss sharing agreement	8 years