FDIC Indemnification Asset - (Summary of Activity Related to FDIC Indemnification Asset) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
FDIC Indemnification Asset [Roll Forward]
Balance at beginning of period	$ 39,082	$ 64,447
Amortization	(20,751)	(27,741)
FDIC portion of charge-offs/recoveries	(2,819)	332
Changes for FDIC loss share submissions	2,644	2,044
Termination of FDIC loss-share agreements	$ (18,156)
Balance at end of period		$ 39,082