PARENT COMPANY ONLY FINANCIAL INFORMATION (Condensed Statements of Cash Flows) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Condensed Financial Statements, Captions [Line Items]
Net income (loss) attributable to First Banks, Inc.	$ 241,744	$ 26,278	$ (41,150)
Adjustments to reconcile net income (loss) from continuing operations to net cash provided by operating activities:
Other, net	4,763	4,356	20,945
Net cash provided by operating activities	122,965	56,182	116,353
Cash flows from financing activities:
Net cash used in financing activities	(125,120)	(174,362)	(647,756)
Net (decrease) increase in cash and cash equivalents	(328,411)	45,706	(522,618)
Cash and cash equivalents, beginning of year	518,846	473,140	995,758
Cash and cash equivalents, end of year	190,435	518,846	473,140
Noncash investing activities:
Cash paid for interest on liabilities	9,540	17,493	35,723
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss) attributable to First Banks, Inc.	241,744	26,278	(41,150)
Adjustments to reconcile net income (loss) from continuing operations to net cash provided by operating activities:
Net (income) loss of subsidiaries	(218,409)	(41,745)	28,290
Other, net	(24,215)	15,410	12,042
Net cash provided by operating activities	(880)	(57)	(818)
Cash flows from financing activities:
Payment of preferred stock dividends	0	0	0
Net cash used in financing activities	0	0	0
Net (decrease) increase in cash and cash equivalents	(880)	(57)	(818)
Cash and cash equivalents, beginning of year	2,744	2,801	3,619
Cash and cash equivalents, end of year	1,864	2,744	2,801
Noncash investing activities:
Cash paid for interest on liabilities	$ 0	$ 0	$ 0