Earnings Per Share - Computation of Earnings Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Net income (loss) per consolidated statements of income	$ 1,717	$ (26,891)	$ 7,788	$ (23,033)
Net (income) loss allocated to participating securities	(4)	73	(22)	43
Amortization of discount on preferred stock			(6,751)
Net income (loss) allocated to common stock	1,713	(26,818)	1,015	(22,990)
Distributed earnings allocated to common stock
Undistributed earnings (loss) allocated to common stock	1,713	(26,818)	1,015	(22,990)
Net income (loss) allocated to common stock	1,713	(26,818)	1,015	(22,990)
Weighted average common shares outstanding, including shares considered participating securities	50,219	32,847	42,455	32,781
Less: Average participating securities	(109)	(96)	(118)	(66)
Weighted average shares	50,110	32,751	42,337	32,715
Basic earnings (loss) per common share	$ 0.03	$ (0.82)	$ 0.02	$ (0.70)
Net income (loss) allocated to common stock	$ 1,713	$ (26,818)	$ 1,015	$ (22,990)
Weighted average common shares outstanding for basic earnings per common share	50,110	32,751	42,337	32,715
Add: Dilutive effects of assumed exercises of stock options	272		275
Weighted average shares and dilutive potential common shares	50,382	32,751	42,612	32,715
Diluted earnings (loss) per common share	$ 0.03	$ (0.82)	$ 0.02	$ (0.70)