Income Taxes - Components of Deferred Tax Assets (Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets:
Allowance for loan losses	$ 10,086	$ 18,870
OREO valuation allowance and other loss reserves	7,506	10,307
Federal NOL carryforwards	61,392	68,237
State NOL carryforwards	15,319	16,343
Unrealized securities losses, net	1,532	963
Alternative minimum tax credit carryforward	2,522	2,129
Deferred gain on sales leaseback	1,986	2,541
Other	3,381	2,994
Total deferred tax assets	103,724	122,384
Valuation allowance	(4,200)	(113,099)	$ (94,800)
Adjusted deferred tax assets	99,524	9,285
Deferred tax liabilities:
FHLB stock dividends	(833)	(833)
Mortgage servicing rights	(7,597)	(7,784)
Other	(474)	(668)
Total deferred tax liabilities	(8,904)	(9,285)
Net deferred tax assets	$ 90,620	$ 0