Parent Company Only Financial Information - Summary of Statement of Cash Flows (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
CASH FLOWS FROM OPERATING ACTIVITIES
Interest received	$ 73,849	$ 78,119	$ 81,904
Interest paid	(5,584)	(9,003)	(16,211)
Income taxes received (paid)	(157)	2	(9)
Net cash provided (used) by operating activities	49,852	(2,062)	23,741
CASH FLOWS FROM INVESTING ACTIVITIES
Net cash (used) by investing activities	(89,155)	(28,421)	(180,869)
CASH FLOWS FROM FINANCING ACTIVITIES
Issuance of common stock, net of related expense	46,977	0	0
Repurchase of stock warrants, including related expense	0	(81)	0
Stock based employment plans	190	196	123
Redemption of preferred stock	(50,000)	0	0
Dividends paid on preferred shares	(2,819)	(2,500)	(6,875)
Net cash provided by financing activities	55,940	38,389	112,804
Net change in cash	16,637	7,906	(44,324)
Cash and cash equivalents at beginning of year	174,987	167,081	211,405
Cash and cash equivalents at end of year	191,624	174,987	167,081
RECONCILIATION OF INCOME (LOSS) TO CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES
NET INCOME (LOSS)	51,989	(710)	6,667
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Net change in other assets	792	(835)	585
Net cash provided (used) by operating activities	49,852	(2,062)	23,741
Parent Company [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Interest received	5	7	9
Interest paid	(957)	(1,045)	(3,288)
Dividends received	23	22	70
Income taxes received (paid)	1,797	(32)	(67)
Other	(494)	(703)	(420)
Net cash provided (used) by operating activities	374	(1,751)	(3,696)
CASH FLOWS FROM INVESTING ACTIVITIES
Decrease in securities purchased under agreement to resell, maturing within 30 days, net	2,130	422	285
Net cash (used) by investing activities	2,130	422	285
CASH FLOWS FROM FINANCING ACTIVITIES
Issuance of common stock, net of related expense	46,977	0	0
Repurchase of stock warrants, including related expense	0	(81)	0
Stock based employment plans	190	196	123
Redemption of preferred stock	(50,000)	0	0
Dividends paid on preferred shares	(2,819)	(2,500)	(6,875)
Net cash provided by financing activities	(5,652)	(2,385)	(6,752)
Net change in cash	(3,148)	(3,714)	(10,163)
Cash and cash equivalents at beginning of year	4,067	7,781	17,944
Cash and cash equivalents at end of year	919	4,067	7,781
RECONCILIATION OF INCOME (LOSS) TO CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES
NET INCOME (LOSS)	51,989	(710)	6,667
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Equity in undistributed income of subsidiaries	(51,088)	(893)	(8,145)
Net change in other assets	(527)	(148)	(2,218)
Net cash provided (used) by operating activities	$ 374	$ (1,751)	$ (3,696)