First Financial Holdings, Inc. (Parent Company Only) Condensed Financial Information (Detail) - Schedule of Condensed Cash Flow Statement (USD $) In Thousands, unless otherwise specified	3 Months Ended				12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Sep. 30, 2010
Net income (loss)	$ 15,572		$ 1,167		$ 28,813		$ (41,186)	$ (36,789)
Adjustments to reconcile net income to net cash (used in) provided by operating activities
Amortization of issuance cost, junior subordinated debt	(4,483)		(3,020)
Recognition of stock based compensation expense (benefit)	59		179		180		432	(219)
Other	(1,336)	[1]	6,081	[1]
Net cash (used in) provided by operating activities	3,052	[1]	18,110	[1]	64,845	3,100	104,171	47,897
Investing Activities
Net cash used in investing activities	49,948	[1]	(4,142)	[1]	514,351	3,800	30,346	78,355
Financing Activities
Net decrease in other borrowings	0				0		0	(258,001)
Proceeds from issuance of common stock	0				0		0	9,166
Proceeds from exercise of stock options	0				0		0	19
Dividends paid on preferred stock	813		813		3,250		3,250	3,252
Dividends paid on common stock	(826)		(826)
Net cash used in financing activities	(62,262)		(18,090)		(538,420)		(109,128)	(144,016)
Net (decrease) increase in cash and cash equivalents	(9,262)		(4,122)		40,776		25,389	(17,764)
Cash and cash equivalents at beginning of period	85,937		60,548		76,675	56,426	60,548	78,312
Cash and cash equivalents at end of period	76,675		56,426		117,451	76,675	85,937	60,548
Cash paid during the period for
Interest	8,987		11,907
Income taxes	0				5,660		3,998	0
Parent [Member]
Net income (loss)	15,572				28,813		(41,186)	(36,789)
Adjustments to reconcile net income to net cash (used in) provided by operating activities
(Increase) decrease of equity in undistributed earnings of subsidiaries	(16,432)				(33,715)		82,575	32,961
Amortization of issuance cost, junior subordinated debt	14				244		55	55
Recognition of stock based compensation expense (benefit)	56				176		432	(219)
Tax benefit resulting from stock options	0				0		0	(3)
Other	(2,487)				2,242		3,337	(993)
Net cash (used in) provided by operating activities	(3,277)				(2,240)		45,213	(4,988)
Investing Activities
Proceeds from repayment and sales of investments	0				9		775	22
Equity investments in subsidiaries	0				(12,000)		(20,875)	(45,594)
Net cash used in investing activities	0				(11,991)		(20,100)	(45,572)
Financing Activities
Net decrease in other borrowings	0				0		0	(28,000)
Proceeds from issuance of common stock	0				0		0	9,173
Proceeds from exercise of stock options	0				0		0	19
Tax benefit resulting from stock options	0				0		0	3
Dividends paid on preferred stock	(813)				(3,384)		(3,250)	(3,252)
Dividends paid on common stock	(826)				(3,305)		(3,306)	(3,304)
Net cash used in financing activities	(1,639)				(6,689)		(6,556)	(25,361)
Net (decrease) increase in cash and cash equivalents	(4,916)				(20,920)		18,557	(75,921)
Cash and cash equivalents at beginning of period	43,931		25,374		39,015		25,374	101,295
Cash and cash equivalents at end of period	39,015				18,095	39,015	43,931	25,374
Cash paid during the period for
Interest	787				3,150		3,150	3,356
Income taxes	$ 0				$ 2,040		$ 715	$ 0

[1] Certain amounts have been reclassified from the original presentation in the Consolidated Statement of Cash Flows as reported in the Form 10-Q for the transitional quarter ended December 31, 2011, to conform with current period presentation. Certain amounts have been reclassified to conform to the presentation for the quarter ended December 31, 2011.