First Banks (FBSPRA) 10-Q 14 May 15 2015 Q1 Quarterly report Financial data

DOCUMENT_AND_ENTITY_INFORMATIO

DOCUMENT AND ENTITY INFORMATION	3 Months Ended
	Mar. 31, 2015	14-May-15
Entity Registrant Name	FIRST BANKS, INC
Entity Central Index Key	710507
Current Fiscal Year End Date	-19
Entity Filer Category	Non-accelerated Filer
Trading Symbol	fbspra
Entity Common Stock, Shares Outstanding		23,661
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2015

CONSOLIDATED_BALANCE_SHEETS_UN

CONSOLIDATED BALANCE SHEETS (UNAUDITED) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
ASSETS
Cash and due from banks	$97,255	$100,349
Short-term investments	133,480	105,053
Total cash and cash equivalents	230,735	205,402
Investment securities:
Available for sale	1,554,442	1,445,689
Held to maturity (fair value of $597,341 and $614,272, respectively)	595,335	618,148
Total investment securities	2,149,777	2,063,837
Loans:
Commercial, financial and agricultural	700,183	695,267
Real estate construction and development	110,705	89,851
Real estate mortgage	2,319,175	2,315,186
Consumer and installment	20,956	18,950
Net deferred loan fees	-1,277	-1,422
Total loans held for portfolio	3,149,742	3,117,832
Loans held for sale	43,655	31,411
Total loans	3,193,397	3,149,243
Allowance for loan losses	-64,142	-66,874
Net loans	3,129,255	3,082,369
Federal Reserve Bank and Federal Home Loan Bank stock	30,348	30,458
Bank premises and equipment, net	117,803	123,016
Deferred income taxes	310,698	312,575
Other real estate	15,227	55,666
Other assets	62,787	62,196
Total assets	6,046,630	5,935,519
LIABILITIES
Noninterest-bearing deposits	1,386,562	1,303,519
Interest-bearing deposits	3,585,527	3,545,985
Total deposits	4,972,089	4,849,504
Securities sold under agreements to repurchase	51,032	64,875
Subordinated debentures	354,305	354,286
Deferred income taxes	43,558	40,728
Accrued expenses and other liabilities	106,275	113,682
Total liabilities	5,527,259	5,423,075
STOCKHOLDERS’ EQUITY
Common stock, $250.00 par value, 25,000 shares authorized, 23,661 shares issued and outstanding	5,915	5,915
Additional paid-in capital	324,913	324,913
Retained earnings	67,048	64,374
Accumulated other comprehensive income	14,355	10,111
Total First Banks, Inc. stockholders’ equity	425,604	418,686
Noncontrolling interest in subsidiary	93,767	93,758
Total stockholders’ equity	519,371	512,444
Total liabilities and stockholders’ equity	6,046,630	5,935,519
Class A Convertible Adjustable Rate Preferred Stock [Member]
STOCKHOLDERS’ EQUITY
Preferred stock	12,822	12,822
Class B Adjustable Rate Preferred Stock [Member]
STOCKHOLDERS’ EQUITY
Preferred stock	241	241
Class C Fixed Rate Cumulative Perpetual Preferred Stock [Member]
STOCKHOLDERS’ EQUITY
Preferred stock	295	295
Class D Fixed Rate Cumulative Perpetual Preferred Stock [Member]
STOCKHOLDERS’ EQUITY
Preferred stock	$15	$15

CONSOLIDATED_BALANCE_SHEETS_UN1

CONSOLIDATED BALANCE SHEETS (UNAUDITED) [Parenthetical] (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, except Share data, unless otherwise specified
Held-to-maturity securities, fair value (in dollars)	$597,341	$614,272
Common stock, par value (in dollars per share)	$250	$250
Common stock, shares authorized	25,000	25,000
Common stock, shares issued	23,661	23,661
Common stock, shares outstanding	23,661	23,661
Class A Convertible Adjustable Rate Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$20	$20
Preferred stock, shares authorized	750,000	750,000
Preferred stock, shares issued	641,082	641,082
Preferred stock, shares outstanding	641,082	641,082
Class B Adjustable Rate Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$1.50	$1.50
Preferred stock, shares authorized	200,000	200,000
Preferred stock, shares issued	160,505	160,505
Preferred stock, shares outstanding	160,505	160,505
Class C Fixed Rate Cumulative Perpetual Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$1	$1
Preferred stock, shares authorized	295,400	295,400
Preferred stock, shares issued	295,400	295,400
Preferred stock, shares outstanding	295,400	295,400
Class D Fixed Rate Cumulative Perpetual Preferred Stock [Member]
Preferred stock, par value (in dollars per share)	$1	$1
Preferred stock, shares authorized	14,770	14,770
Preferred stock, shares issued	14,770	14,770
Preferred stock, shares outstanding	14,770	14,770

CONSOLIDATED_STATEMENTS_OF_INC

CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Interest income:
Interest and fees on loans	$30,003	$29,079
Investment securities	11,178	12,632
Federal Reserve Bank and Federal Home Loan Bank stock	360	358
Short-term investments	125	120
Total interest income	41,666	42,189
Interest expense:
Deposits	2,051	2,034
Other borrowings	13	4
Subordinated debentures	3,015	3,811
Total interest expense	5,079	5,849
Net interest income	36,587	36,340
Provision for loan losses	0	0
Net interest income after provision for loan losses	36,587	36,340
Noninterest income:
Service charges on deposit accounts and client service fees	8,104	8,333
Gain on loans sold and held for sale	2,837	865
Net gain on investment securities	43	1,280
Net gain on sale of other real estate	4,992	442
Decrease in fair value of servicing rights	-1,472	-232
Loan servicing fees	1,580	1,711
Other	2,044	1,886
Total noninterest income	18,128	14,285
Noninterest expense:
Salaries and employee benefits	22,903	19,882
Occupancy, net of rental income	5,396	5,784
Furniture and equipment	3,304	2,360
Postage, printing and supplies	583	639
Information technology fees	5,346	5,220
Legal, examination and professional fees	907	1,291
Advertising and business development	687	622
FDIC insurance	945	1,264
Write-downs and expenses on other real estate	232	699
Other	10,116	4,597
Total noninterest expense	50,419	42,358
Income before provision for income taxes	4,296	8,267
Provision for income taxes	1,613	2,917
Net income	2,683	5,350
Less: net income (loss) attributable to noncontrolling interest in subsidiary	9	-55
Net income attributable to First Banks, Inc.	$2,674	$5,405

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Net income	$2,683	$5,350
Other comprehensive income (loss):
Unrealized gains on available-for-sale investment securities	7,949	8,217
Reclassification adjustment for available-for-sale investment securities gains included in net income	-43	-1,280
Amortization of net unrealized gain associated with transfer of available-for-sale investment securities to held-to-maturity investment securities	-746	-683
Income tax effect	-2,948	-2,575
Changes in unrealized gains on securities, net of tax	4,212	3,679
Reclassification adjustment for amortization of net actuarial loss on pension plan	55	35
Income tax effect	-23	-14
Changes in defined benefit pension plans, net of tax	32	21
Other comprehensive income	4,244	3,700
Comprehensive income	6,927	9,050
Net income (loss) attributable to noncontrolling interest in subsidiary	9	-55
Comprehensive income attributable to First Banks, Inc.	$6,918	$9,105

CONSOLIDATED_STATEMENTS_OF_CHA

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (UNAUDITED) (USD $)	Total	First Banks, Inc. Stockholders’ Equity, Preferred Stock [Member]	First Banks, Inc. Stockholders’ Equity, Common Stock [Member]	First Banks, Inc. Stockholders’ Equity, Additional Paid-In Capital [Member]	First Banks, Inc. Stockholders’ Equity, Retained Earnings [Member]	First Banks, Inc. Stockholders’ Equity, Accumulated Other Comprehensive Income [Member]	Noncontrolling Interest [Member]
In Thousands, unless otherwise specified
Balance, beginning of period at Dec. 31, 2013	$488,256	$13,373	$5,915	$324,913	$42,719	$7,502	$93,834
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	5,350				5,405		-55
Other comprehensive income	3,700					3,700
Balance, end of period at Mar. 31, 2014	497,306	13,373	5,915	324,913	48,124	11,202	93,779
Balance, beginning of period at Dec. 31, 2014	512,444	13,373	5,915	324,913	64,374	10,111	93,758
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,683				2,674		9
Other comprehensive income	4,244					4,244
Balance, end of period at Mar. 31, 2015	$519,371	$13,373	$5,915	$324,913	$67,048	$14,355	$93,767

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$2,683	$5,350
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization of bank premises and equipment	2,897	2,921
Amortization and accretion of investment securities	5,574	5,799
Originations of loans held for sale	-86,557	-35,414
Proceeds from sales of loans held for sale	76,049	40,278
Provision for current income taxes	1	283
Provision for deferred income taxes	1,612	2,634
(Increase) decrease in accrued interest receivable	-803	1,711
Decrease in accrued interest payable	-1	-62,685
Gain on loans sold and held for sale	-2,837	-865
Net gain on investment securities	-43	-1,280
Decrease in fair value of servicing rights	1,472	232
Write-downs on other real estate	109	97
Other operating activities, net	-6,657	-156
Net cash used in operating activities	-6,501	-41,095
Cash flows from investing activities:
Net cash paid for sale of assets and liabilities of discontinued operations, net of cash and cash equivalents sold	0	-15,467
Proceeds from sales of investment securities available for sale	44,768	166,320
Maturities of investment securities available for sale	47,113	44,399
Maturities of investment securities held to maturity	19,371	17,783
Purchases of investment securities available for sale	-193,538	-250
Purchases of investment securities held to maturity	-2,025	-1,429
Net redemptions (purchases) of Federal Reserve Bank and Federal Home Loan Bank stock	110	-4,791
Proceeds from sales of commercial loans	1,804	0
Net increase in loans	-38,099	-41,400
Purchases of bank premises and equipment	-2,188	-1,923
Net proceeds from sales of other real estate	45,658	5,876
Other investing activities, net	118	671
Net cash (used in) provided by investing activities	-76,908	169,789
Cash flows from financing activities:
Increase in deposits	122,585	28,536
Decrease in securities sold under agreements to repurchase	-13,843	-6,430
Net cash provided by financing activities	108,742	22,106
Net increase in cash and cash equivalents	25,333	150,800
Cash and cash equivalents, beginning of period	205,402	190,435
Cash and cash equivalents, end of period	230,735	341,235
Supplemental disclosures of cash flow information:
Cash paid for interest on liabilities	5,080	68,534
Cash paid for income taxes	2	257
Noncash investing and financing activities:
Loans transferred to other real estate	$459	$1,031

BASIS_OF_PRESENTATION

BASIS OF PRESENTATION	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
BASIS OF PRESENTATION	BASIS OF PRESENTATION
	Basis of Presentation. The consolidated financial statements of First Banks, Inc. and subsidiaries (“the Company”) are unaudited and should be read in conjunction with the consolidated financial statements contained in the Company’s 2014 Annual Report on Form 10-K. The consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and conform to predominant practices within the banking industry. Certain disclosures pertaining to companies whose common stock is not publicly traded have been omitted from the Company’s financial statements in accordance with GAAP requirements. Management of the Company has made a number of estimates and assumptions relating to the reporting of assets and liabilities and the disclosure of contingent assets and liabilities to prepare the consolidated financial statements in conformity with GAAP. Actual results could differ from those estimates. In the opinion of management, all adjustments, consisting of normal recurring accruals considered necessary for a fair presentation of the results of operations for the interim periods presented herein, have been included. Operating results for the three months ended March 31, 2015 are not necessarily indicative of the results that may be expected for the year ending December 31, 2015. Certain reclassifications of 2014 amounts have been made to conform to the 2015 presentation. All financial information is reported on a continuing operations basis.
	Principles of Consolidation. The consolidated financial statements include the accounts of the parent company and its subsidiaries, giving effect to the noncontrolling interest in subsidiary, as more fully described below and in Note 11 to the consolidated financial statements. All significant intercompany accounts and transactions have been eliminated.
	The Company operates through its wholly owned subsidiary bank holding company, The San Francisco Company (“SFC”), headquartered in St. Louis, Missouri, and SFC’s wholly owned subsidiary bank, First Bank, also headquartered in St. Louis, Missouri. First Bank operates through its branch banking offices and subsidiaries. All of the subsidiaries are wholly owned as of March 31, 2015 except FB Holdings, LLC (“FB Holdings”), which is 53.23% owned by First Bank and 46.77% owned by First Capital America, Inc. (“FCA”), a corporation owned and operated by the Company’s Chairman of the Board and members of his immediate family, including Mr. Michael Dierberg, Vice Chairman of the Company, and Ms. Ellen Dierberg Milne, Director of the Company, as further described in Note 11 to the consolidated financial statements. FB Holdings is included in the consolidated financial statements and the noncontrolling ownership interest is reported as a component of stockholders’ equity in the consolidated balance sheets as “noncontrolling interest in subsidiary” and the earnings or loss, net of tax, attributable to the noncontrolling ownership interest, is reported as “net income (loss) attributable to noncontrolling interest in subsidiary” in the consolidated statements of income.

INVESTMENTS_IN_DEBT_AND_EQUITY

INVESTMENTS IN DEBT AND EQUITY SECURITIES	3 Months Ended
	Mar. 31, 2015
Investments, Debt and Equity Securities [Abstract]
INVESTMENTS IN DEBT AND EQUITY SECURITIES	INVESTMENTS IN DEBT AND EQUITY SECURITIES
	Securities Available for Sale. The amortized cost, contractual maturity, gross unrealized gains and losses and fair value of investment securities available for sale at March 31, 2015 and December 31, 2014 were as follows:
		Maturity									Total Amortized Cost	Gross					Weighted Average Yield
		1 Year			5-Jan		10-May		After			Unrealized				Fair
	(dollars in thousands)	or Less			Years		Years		10 Years			Gains		Losses		Value
	March 31, 2015:
	Carrying value:
	U.S. Government sponsored agencies	$	—		29,904		20,114		201,168		251,186	2,093		(727	)	252,552	1.45	%
	Residential mortgage-backed	—			65,101		79,250		895,399		1,039,750	18,814		(2,308	)	1,056,256	2.38
	Commercial mortgage-backed	—			775		—		—		775	63		—		838	4.95
	State and political subdivisions	511			569		—		28,356		29,436	26		(268	)	29,194	1.04
	Corporate notes	38,640			67,069		81,388		24,449		211,546	2,870		(799	)	213,617	2.55
	Equity investments	—			—		—		2,000		2,000	—		(15	)	1,985	2.14
	Total	$	39,151		163,418		180,752		1,151,372		1,534,693	23,866		(4,117	)	1,554,442	2.23
	Fair value:
	Debt securities	$	39,606		166,357		184,307		1,162,187
	Equity securities	—			—		—		1,985
	Total	$	39,606		166,357		184,307		1,164,172
	Weighted average yield	2.57		%	1.96	%	2.58	%	2.2	%
	December 31, 2014:
	Carrying value:
	U.S. Government sponsored agencies	$	—		29,942		20,119		180,098		230,159	2,129		(557	)	231,731	1.39	%
	Residential mortgage-backed	269			65,433		48,174		885,896		999,772	14,189		(6,117	)	1,007,844	2.39
	Commercial mortgage-backed	—			779		—		—		779	58		—		837	4.95
	State and political subdivisions	863			571		—		28,371		29,805	33		(223	)	29,615	1.05
	Corporate notes	27,382			72,959		70,990		—		171,331	2,759		(395	)	173,695	2.75
	Equity investments	—			—		—		2,000		2,000	—		(33	)	1,967	2.15
	Total	$	28,514		169,684		139,283		1,096,365		1,433,846	19,168		(7,325	)	1,445,689	2.25
	Fair value:
	Debt securities	$	28,901		172,561		140,717		1,101,543
	Equity securities	—			—		—		1,967
	Total	$	28,901		172,561		140,717		1,103,510
	Weighted average yield	2.64		%	1.97	%	2.58	%	2.23	%
	Securities Held to Maturity. The amortized cost, contractual maturity, gross unrealized gains and losses and fair value of investment securities held to maturity at March 31, 2015 and December 31, 2014 were as follows:
		Maturity									Total Amortized Cost	Gross					Weighted Average Yield
		1 Year			5-Jan		10-May		After			Unrealized				Fair
	(dollars in thousands)	or Less			Years		Years		10 Years			Gains		Losses		Value
	March 31, 2015:
	Carrying value:
	U.S. Government sponsored agencies	$	—		—		10,001		—		10,001	64		—		10,065	1.29	%
	Residential mortgage-backed	—			103,224		48,400		429,339		580,963	4,013		(1,984	)	582,992	1.89
	State and political subdivisions	561			660		2,189		961		4,371	1		(88	)	4,284	1.78
	Total	$	561		103,884		60,590		430,300		595,335	4,078		(2,072	)	597,341	1.88
	Fair value:
	Debt securities	$	561		104,797		61,100		430,883
	Weighted average yield	3.07		%	1.93	%	1.25	%	1.95	%
	December 31, 2014:
	Carrying value:
	U.S. Government sponsored agencies	$	—		—		10,725		—		10,725	42		—		10,767	1.25	%
	Residential mortgage-backed	—			105,660		50,512		448,905		605,077	1,931		(5,782	)	601,226	1.86
	State and political subdivisions	561			335		489		961		2,346	1		(68	)	2,279	1.68
	Total	$	561		105,995		61,726		449,866		618,148	1,974		(5,850	)	614,272	1.85
	Fair value:
	Debt securities	$	561		106,147		62,000		445,564
	Weighted average yield	3.07		%	1.88	%	1.13	%	1.94	%
	Proceeds from sales of available-for-sale investment securities were $44.8 million and $166.3 million for the three months ended March 31, 2015 and 2014, respectively. Gross realized gains and gross realized losses on investment securities for the three months ended March 31, 2015 and 2014 were as follows:
		Three Months Ended
		March 31,
	(dollars in thousands)	2015			2014
	Gross realized gains on sales of available-for-sale securities	$	560		2,010
	Gross realized losses on sales of available-for-sale securities	(517		)	(730	)
	Net realized gain on investment securities	$	43		1,280
	Residential and commercial mortgage-backed securities are primarily issued by U.S. government sponsored enterprises and U.S. government agencies. Investment securities with a carrying value of $366.4 million and $349.0 million at March 31, 2015 and December 31, 2014, respectively, were pledged in connection with deposits of public and trust funds, securities sold under agreements to repurchase and for other purposes as required by law.
	Gross unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at March 31, 2015 and December 31, 2014, were as follows:
	Less Than 12 Months					12 Months or More				Total
(dollars in thousands)	Fair Value			Unrealized		Fair Value		Unrealized		Fair Value	Unrealized
				Losses				Losses			Losses
March 31, 2015:
Available for sale:
U.S. Government sponsored agencies	$	86,684		(592	)	14,600		(135	)	101,284	(727	)
Residential mortgage-backed	66,185			(252	)	117,535		(2,056	)	183,720	(2,308	)
State and political subdivisions	28,087			(268	)	—		—		28,087	(268	)
Corporate notes	20,274			(756	)	4,957		(43	)	25,231	(799	)
Equity investments	1,985			(15	)	—		—		1,985	(15	)
Total	$	203,215		(1,883	)	137,092		(2,234	)	340,307	(4,117	)
Held to maturity:
Residential mortgage-backed	$	100,000		(386	)	119,905		(1,598	)	219,905	(1,984	)
State and political subdivisions	2,643			(27	)	899		(61	)	3,542	(88	)
Total	$	102,643		(413	)	120,804		(1,659	)	223,447	(2,072	)
December 31, 2014:
Available for sale:
U.S. Government sponsored agencies	$	79,207		(427	)	14,600		(130	)	93,807	(557	)
Residential mortgage-backed	204,378			(1,154	)	191,644		(4,963	)	396,022	(6,117	)
State and political subdivisions	28,148			(223	)	—		—		28,148	(223	)
Corporate notes	9,650			(350	)	4,955		(45	)	14,605	(395	)
Equity investments	1,967			(33	)	—		—		1,967	(33	)
Total	$	323,350		(2,187	)	211,199		(5,138	)	534,549	(7,325	)
Held to maturity:
Residential mortgage-backed	$	28,371		(112	)	325,820		(5,670	)	354,191	(5,782	)
State and political subdivisions	641			(3	)	896		(65	)	1,537	(68	)
Total	$	29,012		(115	)	326,716		(5,735	)	355,728	(5,850	)
The Company does not believe the investment securities that were in an unrealized loss position at March 31, 2015 and December 31, 2014 are other-than-temporarily impaired. The unrealized losses on the investment securities were primarily attributable to fluctuations in interest rates. It is expected that the securities would not be settled at a price less than the amortized cost. Because the decline in fair value is attributable to changes in interest rates and not credit loss, and because the Company does not intend to sell these investments and it is more likely than not that First Bank will not be required to sell these securities before the anticipated recovery of the remaining amortized cost basis or maturity, these investments are not considered other-than-temporarily impaired. The unrealized losses for investment securities for 12 months or more at March 31, 2015 and December 31, 2014 included 27 and 47 securities, respectively.

LOANS_AND_ALLOWANCE_FOR_LOAN_L

LOANS AND ALLOWANCE FOR LOAN LOSSES	3 Months Ended
	Mar. 31, 2015
Receivables [Abstract]
LOANS AND ALLOWANCE FOR LOAN LOSSES	LOANS AND ALLOWANCE FOR LOAN LOSSES
	The following table summarizes the composition of the loan portfolio at March 31, 2015 and December 31, 2014:
	(dollars in thousands)	March 31,				December 31,
		2015				2014
	Commercial, financial and agricultural	$	700,183			695,267
	Real estate construction and development	110,705				89,851
	Real estate mortgage:
	One-to-four-family residential	1,030,088				1,016,710
	Multi-family residential	114,288				115,434
	Commercial real estate	1,174,799				1,183,042
	Consumer and installment	20,956				18,950
	Net deferred loan fees	(1,277		)		(1,422	)
	Total loans held for portfolio	3,149,742				3,117,832
	Loans held for sale	43,655				31,411
	Total loans	$	3,193,397			3,149,243
	Aging of Loans. The following table presents the aging of loans by loan classification at March 31, 2015 and December 31, 2014:
	(dollars in thousands)	30-59				60-89			Recorded			Nonaccrual			Total Past		Current		Total Loans
		Days				Days			Investment						Due
									> 90 Days
									Accruing
	March 31, 2015:
	Commercial, financial and agricultural	$	59			227			—			7,240			7,526		692,657		700,183
	Real estate construction and development	781				102			—			3,308			4,191		106,514		110,705
	Real estate mortgage:
	Residential mortgage	3,014				952			15			10,911			14,892		613,181		628,073
	Home equity	810				374			—			6,337			7,521		394,494		402,015
	Multi-family residential	—				—			—			18,994			18,994		95,294		114,288
	Commercial real estate	1,201				32			—			4,046			5,279		1,169,520		1,174,799
	Consumer and installment and net deferred loan fees	100				18			—			4			122		19,557		19,679
	Loans held for sale	—				—			—			—			—		43,655		43,655
	Total	$	5,965			1,705			15			50,840			58,525		3,134,872		3,193,397
	December 31, 2014:
	Commercial, financial and agricultural	$	132			430			54			9,486			10,102		685,165		695,267
	Real estate construction and development	431				—			—			3,393			3,824		86,027		89,851
	Real estate mortgage:
	Residential mortgage	2,690				986			35			13,890			17,601		603,567		621,168
	Home equity	1,857				334			72			6,831			9,094		386,448		395,542
	Multi-family residential	—				—			—			19,731			19,731		95,703		115,434
	Commercial real estate	196				54			—			4,122			4,372		1,178,670		1,183,042
	Consumer and installment and net deferred loan fees	136				33			2			23			194		17,334		17,528
	Loans held for sale	—				—			—			—			—		31,411		31,411
	Total	$	5,442			1,837			163			57,476			64,918		3,084,325		3,149,243
	Under the Company’s loan policy, loans are placed on nonaccrual status once principal or interest payments become 90 days past due. However, individual loan officers may submit written requests for approval to continue the accrual of interest on loans that become 90 days past due. These requests may be submitted for approval consistent with the authority levels provided in the Company’s credit approval policies, and they are only granted if an expected near term future event, such as a pending renewal or expected payoff, exists at the time the loan becomes 90 days past due. If the expected near term future event does not occur as anticipated, the loan is then placed on nonaccrual status.
	Credit Quality Indicators. The Company’s credit management policies and procedures focus on identifying, measuring and controlling credit exposure. These procedures employ a lender-initiated system of rating credits, which is ratified in the loan approval process and subsequently tested in internal credit reviews and regulatory bank examinations. The system requires the rating of all loans at the time they are originated or acquired, except for homogeneous categories of loans, such as residential real estate mortgage loans and consumer loans. These homogeneous loans are assigned an initial rating based on the Company’s experience with each type of loan. The Company adjusts the ratings of the homogeneous loans based on payment experience subsequent to their origination.
	The Company includes adversely rated credits, including loans requiring close monitoring that would not normally be considered classified credits by the Company’s regulators, on its monthly loan watch list. Loans may be added to the Company’s watch list for reasons that are temporary and correctable, such as the absence of current financial statements of the borrower or a deficiency in loan documentation. Loans may also be added to the Company’s watch list whenever any adverse circumstance is detected which might affect the borrower’s ability to comply with the contractual terms of the loan. The delinquency of a scheduled loan payment, deterioration in the borrower’s financial condition identified in a review of periodic financial statements, a decrease in the value of the collateral securing the loan, or a change in the economic environment within which the borrower operates could initiate the addition of a loan to the Company’s watch list. Loans on the Company’s watch list require periodic detailed loan status reports prepared by the responsible officer which are discussed in formal meetings with credit review and credit administration staff members. Upgrades and downgrades of loan risk ratings may be initiated by the responsible loan officer. However, upgrades of risk ratings associated with significant credit relationships and/or problem credit relationships may only be made with the concurrence of appropriate regional credit officers.
	Under the Company’s risk rating system, special mention loans are those loans that do not currently expose the Company to sufficient risk to warrant classification as substandard, troubled debt restructuring (“TDR”) or nonaccrual, but possess weaknesses that deserve management’s close attention. Substandard loans include those loans characterized by the distinct possibility that the Company will sustain some loss if the deficiencies are not corrected. A loan is classified as a TDR when a borrower is experiencing financial difficulties that lead to the restructuring of a loan, and the Company grants concessions to the borrower in the restructuring that it would not otherwise consider. Loans classified as TDRs which are accruing interest are classified as performing TDRs. Loans classified as TDRs which are not accruing interest are classified as nonperforming TDRs and are included with all other nonaccrual loans for presentation purposes. Loans classified as nonaccrual have all the weaknesses inherent in those loans classified as substandard with the added characteristic that the weaknesses present make collection or liquidation in full, on the basis of the currently existing facts, conditions and values, highly questionable and improbable. Loans not meeting the criteria above that are analyzed individually as part of the above described process are considered to be pass-rated loans.
	The following tables present the credit exposure of the loan portfolio by internally assigned credit grade and payment activity as of March 31, 2015 and December 31, 2014:
	Commercial Loan Portfolio	Commercial				Real Estate			Multi-family			Commercial			Total
	Credit Exposure by Internally Assigned Credit Grade	and				Construction						Real Estate
	(dollars in thousands)	Industrial				and
						Development
	March 31, 2015:
	Pass	$	663,849			106,986			88,787			1,145,244			2,004,866
	Special mention	16,359				92			5,870			17,700			40,021
	Substandard	12,463				—			637			7,809			20,909
	Performing troubled debt restructuring	272				319			—			—			591
	Nonaccrual	7,240				3,308			18,994			4,046			33,588
	Total	$	700,183			110,705			114,288			1,174,799			2,099,975
	December 31, 2014:
	Pass	$	653,951			85,973			89,148			1,147,824			1,976,896
	Special mention	18,713				143			5,945			20,691			45,492
	Substandard	12,833				—			610			6,640			20,083
	Performing troubled debt restructuring	284				342			—			3,765			4,391
	Nonaccrual	9,486				3,393			19,731			4,122			36,732
Total	$	695,267			89,851			115,434			1,183,042			2,083,594
Consumer Loan Portfolio	Residential Mortgage				Home			Consumer and Installment and Net Deferred Loan Fees			Total
Credit Exposure by Payment Activity					Equity
(dollars in thousands)
March 31, 2015:
Pass	$	537,729			394,494			19,557			951,780
Substandard	1,893				1,184			118			3,195
Performing troubled debt restructuring	77,540				—			—			77,540
Nonaccrual	10,911				6,337			4			17,252
Total	$	628,073			402,015			19,679			1,049,767
December 31, 2014:
Pass	$	528,388			386,448			17,334			932,170
Substandard	2,662				2,263			171			5,096
Performing troubled debt restructuring	76,228				—			—			76,228
Nonaccrual	13,890				6,831			23			20,744
Total	$	621,168			395,542			17,528			1,034,238
Impaired Loans. Loans deemed to be impaired include performing TDRs and nonaccrual loans. Impaired loans with outstanding balances equal to or greater than $500,000 are evaluated individually for impairment. For these loans, the Company measures the level of impairment based on the present value of the estimated projected cash flows, or if the impaired loans are collateral dependent, the estimated value of the collateral, less applicable selling costs. If the current valuation is lower than the current book balance of the loan, the amount of the difference is evaluated for possible charge-off. In instances where management determines that a charge-off is not appropriate, a specific reserve is established for the individual loan in question. This specific reserve is included as a part of the overall allowance for loan losses.
The following tables present the recorded investment, unpaid principal balance, related allowance for loan losses, average recorded investment and interest income recognized while on impaired status for impaired loans without a related allowance for loan losses and for impaired loans with a related allowance for loan losses by loan classification at March 31, 2015 and December 31, 2014:
(dollars in thousands)	Recorded				Unpaid			Related			Average			Interest
	Investment				Principal			Allowance for			Recorded			Income
					Balance			Loan Losses			Investment			Recognized
March 31, 2015:
With No Related Allowance Recorded:
Commercial, financial and agricultural	$	2,505			3,401			—			2,881			—
Real estate construction and development	2,622				12,318			—			2,661			—
Real estate mortgage:
Residential mortgage	—				—			—			—			—
Home equity	—				—			—			—			—
Multi-family residential	18,675				24,647			—			19,038			—
Commercial real estate	—				—			—			—			—
Consumer and installment	—				—			—			—			—
	23,802				40,366			—			24,580			—
With A Related Allowance Recorded:
Commercial, financial and agricultural	5,007				7,754			479			5,760			3
Real estate construction and development	1,005				3,259			231			1,020			4
Real estate mortgage:
Residential mortgage	88,451				104,415			6,976			89,285			521
Home equity	6,337				7,487			1,267			6,584			—
Multi-family residential	319				3,185			1,212			325			—
Commercial real estate	4,046				5,813			258			5,967			—
Consumer and installment	4				4			—			14			5
	105,169				131,917			10,423			108,955			533
Total:
Commercial, financial and agricultural	7,512				11,155			479			8,641			3
Real estate construction and development	3,627				15,577			231			3,681			4
Real estate mortgage:
Residential mortgage	88,451				104,415			6,976			89,285			521
Home equity	6,337				7,487			1,267			6,584			—
Multi-family residential	18,994				27,832			1,212			19,363			—
Commercial real estate	4,046				5,813			258			5,967			—
Consumer and installment	4				4			—			14			5
	$	128,971			172,283			10,423			133,535			533
(dollars in thousands)	Recorded				Unpaid			Related			Average			Interest
	Investment				Principal			Allowance for			Recorded			Income
					Balance			Loan Losses			Investment			Recognized
December 31, 2014:
With No Related Allowance Recorded:
Commercial, financial and agricultural	$	1,937			2,911			—			2,278			—
Real estate construction and development	2,626				12,333			—			3,106			—
Real estate mortgage:
Residential mortgage	—				—			—			—			—
Home equity	—				—			—			—			—
Multi-family residential	19,050				24,759			—			25,234			959
Commercial real estate	4,119				4,190			—			6,063			116
Consumer and installment	—				—			—			—			—
	27,732				44,193			—			36,681			1,075
With A Related Allowance Recorded:
Commercial, financial and agricultural	7,833				22,089			1,626			9,212			6
Real estate construction and development	1,109				3,403			219			1,312			17
Real estate mortgage:
Residential mortgage	90,118				106,163			7,639			94,835			2,082
Home equity	6,831				7,988			1,366			7,056			—
Multi-family residential	681				3,581			1,157			902			—
Commercial real estate	3,768				5,619			463			5,546			21
Consumer and installment	23				23			1			14			—
	110,363				148,866			12,471			118,877			2,126
Total:
Commercial, financial and agricultural	9,770				25,000			1,626			11,490			6
Real estate construction and development	3,735				15,736			219			4,418			17
Real estate mortgage:
Residential mortgage	90,118				106,163			7,639			94,835			2,082
Home equity	6,831				7,988			1,366			7,056			—
Multi-family residential	19,731				28,340			1,157			26,136			959
Commercial real estate	7,887				9,809			463			11,609			137
Consumer and installment	23				23			1			14			—
	$	138,095			193,059			12,471			155,558			3,201
Recorded investment represents the Company’s investment in its impaired loans (excluding accrued interest receivable and fees) reduced by cumulative charge-offs recorded against the allowance for loan losses on these same loans. At March 31, 2015 and December 31, 2014, the Company had recorded charge-offs of $43.3 million and $55.0 million, respectively, on its impaired loans, representing the difference between the unpaid principal balance and the recorded investment reflected in the tables above. The unpaid principal balance represents the principal amount contractually owed to the Company by the borrowers on the impaired loans.
Troubled Debt Restructurings. In the ordinary course of business, the Company modifies loan terms across loan types, including both consumer and commercial loans, for a variety of reasons. Modifications to consumer loans may include, but are not limited to, changes in interest rate, maturity, amortization and financial covenants. In the original underwriting, loan terms are established that represent the then current and projected financial condition of the borrower. Over any period of time, modifications to these loan terms may be required due to changes in the original underwriting assumptions. These changes may include the financial covenants of the borrower as well as underwriting standards.
Loan modifications are generally performed at the request of the borrower, whether commercial or consumer, and may include reductions in interest rates, changes in payments and maturity date extensions. Although the Company does not have formal, standardized loan modification programs for its commercial or consumer loan portfolios, it addresses loan modifications on a case-by-case basis and also participates in the United States Department of the Treasury’s (“U.S. Treasury”) Home Affordable Modification Program (“HAMP”). HAMP gives qualifying homeowners an opportunity to refinance into more affordable monthly payments, with the U.S. Treasury compensating the Company for a portion of the reduction in monthly amounts due from borrowers participating in this program. At March 31, 2015 and December 31, 2014, the Company had $72.8 million and $72.7 million, respectively, of modified loans in the HAMP program.
For a loan modification to be classified as a TDR, all of the following conditions must be present: (1) the borrower is experiencing financial difficulty, (2) the Company makes a concession to the original contractual loan terms and (3) the Company would not consider the concessions but for economic or legal reasons related to the borrower’s financial difficulty. Modifications of loan terms to borrowers experiencing financial difficulty are made in an attempt to protect as much of the investment in the loan as possible. These modifications are generally made to either prevent a loan from becoming nonaccrual or to return a nonaccrual loan to performing status based on the expectations that the borrower can adequately perform in accordance with the modified terms.
The determination of whether a modification should be classified as a TDR requires significant judgment after taking into consideration all facts and circumstances surrounding the transaction. No single characteristic or factor, taken alone, is determinative of whether a modification should be classified as a TDR. The fact that a single characteristic is present is not considered sufficient to overcome the preponderance of contrary evidence. Assuming all of the TDR criteria are met, the Company considers one or more of the following concessions to the loan terms to represent a TDR: (1) a reduction of the stated interest rate, (2) an extension of the maturity date or dates at a stated interest rate lower than the current market rate for a new loan with similar terms or (3) forgiveness of principal or accrued interest.
Loans renegotiated at a rate equal to or greater than that of a new loan with comparable risk at the time the contract is modified are excluded from TDR classification in the calendar years subsequent to the renegotiation if the loan is in compliance with the modified terms for at least six months.
The Company does not accrue interest on any TDRs unless it believes collection of all principal and interest under the modified terms is reasonably assured. Generally, six months of consecutive payment performance by the borrower under the restructured terms is required before a TDR is returned to accrual status. However, the period could vary depending upon the individual facts and circumstances of the loan. TDRs accruing interest are classified as performing TDRs. The following table presents the categories of performing TDRs as of March 31, 2015 and December 31, 2014:
(dollars in thousands)	March 31,				December 31,
	2015				2014
Performing Troubled Debt Restructurings:
Commercial, financial and agricultural	$	272			284
Real estate construction and development	319				342
Real estate mortgage:
One-to-four-family residential	77,540				76,228
Commercial real estate	—				3,765
Total performing troubled debt restructurings	$	78,131			80,619
The Company does not accrue interest on TDRs which have been modified for a period less than six months or are not in compliance with the modified terms. These loans are considered nonperforming TDRs and are included with other nonaccrual loans for classification purposes. The following table presents the categories of loans considered nonperforming TDRs as of March 31, 2015 and December 31, 2014:
(dollars in thousands)	March 31,				December 31,
	2015				2014
Nonperforming Troubled Debt Restructurings:
Commercial, financial and agricultural	$	35			243
Real estate construction and development	2,784				2,788
Real estate mortgage:
One-to-four-family residential	3,378				4,003
Multi-family residential	18,676				19,050
Commercial real estate	371				371
Total nonperforming troubled debt restructurings	$	25,244			26,455
Both performing and nonperforming TDRs are considered to be impaired loans. When an individual loan is determined to be a TDR, the amount of impairment is based upon the present value of expected future cash flows discounted at the loan’s effective interest rate or the fair value of the underlying collateral less applicable selling costs. The impairment amount is either charged off as a reduction to the allowance for loan losses or provided for as a specific reserve within the allowance for loan losses. The allowance for loan losses allocated to TDRs was $5.8 million and $6.1 million at March 31, 2015 and December 31, 2014, respectively.
The following table presents loans classified as TDRs that were modified during the three months ended March 31, 2015 and 2014:
	Three Months Ended March 31, 2015										Three Months Ended March 31, 2014
(dollars in thousands)	Number		Pre-				Post-				Number		Pre-			Post-
	of		Modification				Modification				of		Modification			Modification
	Contracts		Outstanding				Outstanding				Contracts		Outstanding			Outstanding
			Recorded				Recorded						Recorded			Recorded
			Investment				Investment						Investment			Investment
Loan Modifications Classified as Troubled Debt Restructurings:
Real estate mortgage:
One-to-four-family residential	6		$	1,723			$	1,640			15		$	2,580		$	2,157
The following table presents TDRs that defaulted within 12 months of modification during the three months ended March 31, 2015 and 2014:
	Three Months Ended						Three Months Ended
	March 31, 2015						March 31, 2014
(dollars in thousands)	Number of		Recorded				Number of		Recorded
	Contracts		Investment				Contracts		Investment
Troubled Debt Restructurings That Subsequently Defaulted:
Real estate mortgage:
One-to-four-family residential	—		$	—			1		$	438
Upon default of a TDR, which is considered to be 90 days or more past due under the modified terms, impairment is measured based on the fair value of the underlying collateral less applicable selling costs. The impairment amount is either charged off as a reduction to the allowance for loan losses or provided for as a specific reserve within the allowance for loan losses.
Allowance for Loan Losses. The following table represents a summary of changes in the allowance for loan losses by portfolio segment for the three months ended March 31, 2015 and 2014:
(dollars in thousands)	Commercial				Real Estate			One-to-			Multi-			Commercial		Consumer		Total
	and				Construction			Four-Family			Family			Real Estate		and
	Industrial				and			Residential			Residential					Installment
					Development
Three Months Ended March 31, 2015:
Allowance for loan losses:
Beginning balance	$	12,574			3,490			24,055			5,630			20,983		142		66,874
Charge-offs	(2,987		)		(40	)		(1,163	)		(189	)		(343	)	(22	)	(4,744	)
Recoveries	1,244				164			500			56			21		27		2,012
Provision (benefit) for loan losses	1,501				(860	)		(906	)		77			225		(37	)	—
Ending balance	$	12,332			2,754			22,486			5,574			20,886		110		64,142
Three Months Ended March 31, 2014:
Allowance for loan losses:
Beginning balance	$	13,401			7,407			32,619			5,249			22,052		305		81,033
Charge-offs	(1,622		)		(30	)		(1,426	)		(132	)		(188	)	(49	)	(3,447	)
Recoveries	752				600			791			7			57		38		2,245
Provision (benefit) for loan losses	1,340				(891	)		(764	)		145			122		48		—
Ending balance	$	13,871			7,086			31,220			5,269			22,043		342		79,831
The following table represents a summary of the impairment method used by loan category at March 31, 2015 and December 31, 2014:
(dollars in thousands)	Commercial				Real Estate			One-to-			Multi-			Commercial		Consumer		Total
	and				Construction			Four-Family			Family			Real Estate		and
	Industrial				and			Residential			Residential					Installment and Net Deferred Loan Fees
					Development
March 31, 2015:
Allowance for loan losses:
Impaired loans individually evaluated for impairment	$	—			—			918			—			—		—		918
Impaired loans collectively evaluated for impairment	479				231			7,325			1,212			258		—		9,505
All other loans collectively evaluated for impairment	11,853				2,523			14,243			4,362			20,628		110		53,719
Total allowance for loan losses	$	12,332			2,754			22,486			5,574			20,886		110		64,142
Loans:
Impaired loans individually evaluated for impairment	$	2,505			2,622			6,899			18,676			—		—		30,702
Impaired loans collectively evaluated for impairment	5,007				1,005			87,889			318			4,046		4		98,269
All other loans collectively evaluated for impairment	692,671				107,078			935,300			95,294			1,170,753		19,675		3,020,771
Total loans	$	700,183			110,705			1,030,088			114,288			1,174,799		19,679		3,149,742
December 31, 2014:
Allowance for loan losses:
Impaired loans individually evaluated for impairment	$	1,053			—			1,184			—			—		—		2,237
Impaired loans collectively evaluated for impairment	573				219			7,821			1,157			463		1		10,234
All other loans collectively evaluated for impairment	10,948				3,271			15,050			4,473			20,520		141		54,403
Total allowance for loan losses	$	12,574			3,490			24,055			5,630			20,983		142		66,874
Loans:
Impaired loans individually evaluated for impairment	$	4,712			2,626			7,388			19,050			3,765		—		37,541
Impaired loans collectively evaluated for impairment	5,058				1,109			89,561			681			4,122		23		100,554
All other loans collectively evaluated for impairment	685,497				86,116			919,761			95,703			1,175,155		17,505		2,979,737
Total loans	$	695,267			89,851			1,016,710			115,434			1,183,042		17,528		3,117,832

SERVICING_RIGHTS

SERVICING RIGHTS	3 Months Ended
	Mar. 31, 2015
Servicing Asset [Abstract]
SERVICING RIGHTS	SERVICING RIGHTS
	Mortgage Banking Activities. At March 31, 2015 and December 31, 2014, the Company serviced mortgage loans for others totaling $1.38 billion and $1.37 billion, respectively. Changes in mortgage servicing rights for the three months ended March 31, 2015 and 2014 were as follows:
		Three Months Ended
		March 31,
	(dollars in thousands)	2015			2014
	Balance, beginning of period	$	14,012		14,211
	Originated mortgage servicing rights	822			455
	Purchased mortgage servicing rights	39			—
	Change in fair value resulting from changes in valuation inputs or assumptions used in valuation model (1)	(831		)	151
	Other changes in fair value (2)	(561		)	(422	)
	Balance, end of period	$	13,481		14,395
	____________________
	-1	The change in fair value resulting from changes in valuation inputs or assumptions used in valuation model primarily reflects the change in discount rates and prepayment speed assumptions, primarily due to changes in interest rates.
	-2	Other changes in fair value reflect changes due to the collection/realization of expected cash flows over time.
	Other Servicing Activities. At March 31, 2015 and December 31, 2014, the Company serviced United States Small Business Administration (“SBA”) loans for others totaling $105.0 million and $114.4 million, respectively. Changes in SBA servicing rights for the three months ended March 31, 2015 and 2014 were as follows:
		Three Months Ended
		March 31,
	(dollars in thousands)	2015			2014
	Balance, beginning of period	$	4,001		4,643
	Originated SBA servicing rights	—			—
	Change in fair value resulting from changes in valuation inputs or assumptions used in valuation model (1)	133			175
	Other changes in fair value (2)	(213		)	(136	)
	Balance, end of period	$	3,921		4,682
	____________________
	-1	The change in fair value resulting from changes in valuation inputs or assumptions used in valuation model primarily reflects the change in discount rates and prepayment speed assumptions, primarily due to changes in interest rates.
	-2	Other changes in fair value reflect changes due to the collection/realization of expected cash flows over time.

DERIVATIVE_INSTRUMENTS

DERIVATIVE INSTRUMENTS	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS	DERIVATIVE INSTRUMENTS
	The Company utilizes derivative instruments to assist in the management of interest rate sensitivity by modifying the repricing, maturity and option characteristics of certain assets and liabilities. The following table summarizes derivative instruments held by the Company, their notional amount, estimated fair values and their location in the consolidated balance sheets at March 31, 2015 and December 31, 2014:
	(dollars in thousands)					Derivatives in Other Assets
		Notional Amount				Fair Value Gain (Loss)
		March 31,			December 31, 2014	March 31,		December 31, 2014
		2015				2015
	Derivative Instruments Not Designated as Hedging Instruments:
	Interest rate lock commitments	$	43,610		20,762	1,268		580
	Forward commitments to sell mortgage-backed securities	71,600			38,300	(284	)	(294	)
	Total	$	115,210		59,062	984		286
	Interest Rate Lock Commitments / Forward Commitments to Sell Mortgage-Backed Securities. Derivative instruments issued by the Company consist of interest rate lock commitments to originate fixed-rate loans to be sold. Commitments to originate fixed-rate loans consist primarily of residential real estate loans. These interest rate lock commitments and loans held for sale are hedged with forward contracts to sell mortgage-backed securities, which expire in June 2015. The fair value of the interest rate lock commitments and forward contracts to sell mortgage-backed securities are included in other assets in the consolidated balance sheets. Changes in the fair value of interest rate lock commitments and forward commitments to sell mortgage-backed securities are recognized in noninterest income on a monthly basis.
	The following table summarizes amounts included in the consolidated statements of income for the three months ended March 31, 2015 and 2014 related to non-hedging derivative instruments:
	(dollars in thousands)		Location of Gain (Loss) Recognized	Amount of Gain (Loss) Recognized
			in Operations on Derivatives	in Operations on Derivatives
				Three Months Ended
				March 31,
				2015		2014
	Derivative Instruments Not Designated as Hedging Instruments:
	Interest rate lock commitments		Gain on loans sold and held for sale	$	688	115
	Forward commitments to sell mortgage-backed securities		Gain on loans sold and held for sale	10		(282	)

SUBORDINATED_DEBENTURES

SUBORDINATED DEBENTURES	3 Months Ended
	Mar. 31, 2015
Subordinated Borrowings [Abstract]
SUBORDINATED DEBENTURES	SUBORDINATED DEBENTURES
	As of March 31, 2015, the Company had 13 affiliated Delaware or Connecticut statutory and business trusts (collectively, “the Trusts”) that were created for the sole purpose of issuing trust preferred securities. The trust preferred securities were issued in private placements, with the exception of First Preferred Capital Trust IV, which was issued in a publicly underwritten offering.
	The Company’s distributions accrued on the junior subordinated debentures were $3.0 million and $3.8 million for the three months ended March 31, 2015 and 2014, respectively, and are included in interest expense in the consolidated statements of income. The structure of the trust preferred securities currently satisfies the regulatory requirements for inclusion, subject to certain limitations, in the Company’s capital base, as further discussed in Note 8 to the consolidated financial statements.
	The terms of the junior subordinated debentures and the related trust indentures allow the Company to defer payments of interest for up to 20 consecutive quarterly periods without triggering a payment default or penalty. Such interest payments are primarily funded through dividends from First Bank. In addition, during a deferral period, the Company may not, among other things and with limited exceptions, pay cash dividends on or repurchase its common stock or preferred stock nor make any payment on outstanding debt obligations that rank equally with or junior to the junior subordinated debentures. In March 2014, the Company paid all of the cumulative deferred interest on its junior subordinated debentures (which had been deferred for 18 quarterly periods), which was subsequently distributed to the trust preferred securities holders on the respective interest payment dates in March and April, 2014. Since that time, the Company has continued to pay interest on its junior subordinated debentures to the respective trustees on the regularly scheduled quarterly payment dates.
	Under its Memorandum of Understanding (“MOU”) with the Federal Reserve Bank of St. Louis (“FRB”), as further discussed in Note 8 to the consolidated financial statements, First Bank has agreed not to declare or pay any dividends, without the prior consent of the FRB, that would cause First Bank to pay dividends in excess of its earnings or make a capital distribution that would cause First Bank's Tier 1 Leverage Ratio to fall below 9.0%. Furthermore, pursuant to Missouri Revised Statutes, First Bank is required to obtain approval from the Missouri Division of Finance (“MDOF”) prior to paying any dividends to the Company, as further described in Note 8 to the consolidated financial statements. The Company is unable to predict whether or when the FRB and/or the MDOF will grant such consent in the future.
	Without the payment of dividends from First Bank, the Company currently lacks the source of income and the liquidity to make future interest payments on the junior subordinated debentures associated with its trust preferred securities. Given restrictions placed upon First Bank, including regulatory restrictions, it may not be able to provide the Company with dividends in an amount sufficient to pay the future interest on the trust preferred securities. In such case, the Company would have to pursue alternative funding sources, but there can be no assurance that the Company will be able to identify and obtain alternative funding due to the uncertainty that such alternative funding sources would be available to the Company on terms and conditions that are acceptable to the Company.

STOCKHOLDERS_EQUITY

STOCKHOLDERS' EQUITY	3 Months Ended
	Mar. 31, 2015
Stockholders' Equity Note [Abstract]
STOCKHOLDERS' EQUITY	STOCKHOLDERS’ EQUITY
	Common Stock. There is no established public trading market for the Company’s common stock. Various trusts, which were established by and are administered by and for the benefit of the Company’s Chairman of the Board and members of his immediate family (including Mr. Michael Dierberg, Vice Chairman of the Company, and Ms. Ellen Dierberg Milne, Director of the Company), own all of the voting stock of the Company other than the Class C Preferred Stock and Class D Preferred Stock (as defined below) that have limited voting rights.
	Preferred Stock. The Company has four classes of preferred stock outstanding.
	The Company suspended the payment of cash dividends on its outstanding common stock and preferred stock beginning with the regularly scheduled quarterly dividend payments on the preferred stock that would otherwise have been made in August and September, 2009. The Company has declared and accrued $68.4 million of its regularly scheduled dividend payments on its Class C Fixed Rate Cumulative Perpetual Preferred Stock (“Class C Preferred Stock”) and Class D Fixed Rate Cumulative Perpetual Preferred Stock (“Class D Preferred Stock”) at March 31, 2015 and December 31, 2014, and has accrued an additional $9.4 million of cumulative dividends on such deferred dividend payments at March 31, 2015 and December 31, 2014. As such, the aggregate amount of these deferred and accrued dividend payments was $77.8 million at March 31, 2015 and December 31, 2014.
	The Company ceased declaring dividends on its Class C Preferred Stock and Class D Preferred Stock during the fourth quarter of 2013. Previously, the Company had declared and accrued dividends on its Class C Preferred Stock and Class D Preferred Stock quarterly throughout the deferral period. If the Company had continued to declare and accrue dividends on its Class C Preferred Stock and Class D Preferred Stock from the fourth quarter of 2013 and forward, the Company would have accrued an additional $46.9 million of dividend payments (including $9.6 million of dividend payments that would have been declared and accrued for the three months ended March 31, 2015), and the Company’s aggregate deferred and accrued dividend payments would have been $124.7 million and $115.1 million at March 31, 2015 and December 31, 2014, respectively. The Company will continue to evaluate whether declaring dividends on its Class C Preferred Stock and Class D Preferred Stock is appropriate in future periods. The Company’s cessation of declaring and accruing dividends on its Class C Preferred Stock and Class D Preferred Stock did not have any effect on the terms of the outstanding Class C Preferred Stock and Class D Preferred Stock, including the Company’s obligations thereunder.
	Accumulated Other Comprehensive Income (Loss). The following table summarizes changes in accumulated other comprehensive income (loss), net of tax, by component, for the three months ended March 31, 2015 and 2014:
	(dollars in thousands)	Investment Securities			Defined Benefit Pension Plan		Total
	Three Months Ended March 31, 2015:
	Balance, beginning of period	$	14,051		(3,940	)	10,111
	Other comprehensive income before reclassifications	4,237			—		4,237
	Amounts reclassified from accumulated other comprehensive income	(25		)	32		7
	Net current period other comprehensive income	4,212			32		4,244
	Balance, end of period	$	18,263		(3,908	)	14,355
	Three Months Ended March 31, 2014:
	Balance, beginning of period	$	10,151		(2,649	)	7,502
	Other comprehensive income before reclassifications	4,432			—		4,432
	Amounts reclassified from accumulated other comprehensive income	(753		)	21		(732	)
	Net current period other comprehensive income	3,679			21		3,700
	Balance, end of period	$	13,830		(2,628	)	11,202

REGULATORY_CAPITAL_AND_OTHER_R

REGULATORY CAPITAL AND OTHER REGULATORY MATTERS	3 Months Ended
	Mar. 31, 2015
Banking and Thrift [Abstract]
REGULATORY CAPITAL AND OTHER REGULATORY MATTERS	REGULATORY CAPITAL AND OTHER REGULATORY MATTERS
	Regulatory Capital. The Company and First Bank are subject to various regulatory capital requirements administered by the federal and state banking agencies. Failure to meet minimum capital requirements can initiate certain actions by regulators that, if undertaken, could have a direct material effect on the operations and financial condition of the Company and First Bank. Under these capital requirements, the Company and First Bank must meet specific capital guidelines that involve quantitative measures of assets, liabilities and certain off-balance sheet items as calculated under regulatory accounting practices. Capital amounts and classifications are also subject to qualitative judgments by the regulators about components, risk weightings and other factors.
	Quantitative measures established by regulation to ensure capital adequacy require the Company and First Bank to maintain minimum amounts and ratios of total capital, Tier 1 capital and common equity Tier 1 capital to risk-weighted assets (as defined in the regulations), and of Tier 1 capital to average assets (“Tier1 leverage ratio”).
	In July 2013, the federal bank regulators approved final rules (the “Final Capital Rules”) implementing the Basel III framework as well as certain provisions of the Dodd-Frank Wall Street Reform and Consumer Protection Act. The Final Capital Rules also substantially revise the risk-based capital requirements applicable to bank holding companies and their depository institution subsidiaries, including the Company and First Bank, as compared to the general risk-based capital rules (the “General Risk-Based Capital Rules”). The Final Capital Rules revise the components of capital and address other issues affecting the numerator in regulatory capital ratios. The Final Capital Rules also address asset risk weights and other issues affecting the denominator in regulatory capital ratios and replace the existing general risk-weighting approach based on Basel I with a more risk-sensitive approach. The Final Capital Rules became effective for the Company and First Bank on January 1, 2015 (subject to a phase-in period for certain provisions). The calculation of common equity Tier 1 capital is different from the calculation of common equity under GAAP. Most significantly for the Company, the Company's net deferred tax assets, which are included in the calculation of common equity under GAAP, will be substantially phased out over time from the required calculation of common equity Tier 1 capital for regulatory purposes. The net deferred tax assets attributable to net operating loss and tax credit carryforwards, which comprised over 91.8% of the Company's net deferred tax assets as of March 31, 2015, are scheduled to be phased out entirely from inclusion in the calculation of common equity Tier 1 capital in 2018. In addition, the inclusion of trust preferred securities eligible for Tier 1 capital is more limited under the Final Capital Rules.
	The Company must maintain minimum total capital, Tier 1 capital, common equity Tier 1 capital and Tier 1 leverage ratios as set forth in the table below in order to meet the minimum capital adequacy standards. The Company was categorized as adequately capitalized under minimum regulatory capital standards established for bank holding companies by the Federal Reserve at December 31, 2014. The Company was not categorized as adequately capitalized under minimum regulatory capital standards established for bank holding companies by the Federal Reserve at March 31, 2015 as a result of not meeting the required common equity Tier 1 requirement under the Final Capital Rules.
	First Bank was categorized as well capitalized at March 31, 2015 and December 31, 2014 under the prompt corrective action provisions of the regulatory capital standards. First Bank must maintain minimum total capital, Tier 1 capital, common equity Tier 1 capital and Tier 1 leverage ratios as set forth in the table below in order to be categorized as well capitalized.
	At March 31, 2015 and December 31, 2014, the Company’s and First Bank’s required and actual capital ratios were as follows:
											Final Capital Rules				General Risk-Based
											(Effective January 1, 2015)				Capital Rules
															(Prior to January 1, 2015)
													To be Well				To be Well
		Actual									For Capital Adequacy Purposes		Capitalized		For Capital Adequacy Purposes		Capitalized
		March 31, 2015					December 31, 2014						Under Prompt Corrective Action Provisions				Under Prompt Corrective Action Provisions
	(dollars in thousands)	Amount			Ratio		Amount		Ratio
	Total capital (to risk-weighted assets):
	First Banks, Inc.	$	582,115		14.88	%	$	475,312	12.25	%	8	%	N/A		8	%	N/A
	First Bank	660,631			16.8		691,350		17.81		8		10	%	8		10	%
	Tier 1 capital (to risk-weighted assets):
	First Banks, Inc.	283,962			7.26		284,396		7.33		6		N/A		4		N/A
	First Bank	612,837			15.59		642,593		16.55		6		8		4		6
	Common equity Tier 1 capital (to risk-weighted assets):
	First Banks, Inc.	(44,624		)	(1.14	)	N/A		N/A		4.5		N/A		N/A		N/A
	First Bank	612,837			15.59		N/A		N/A		4.5		6.5		N/A		N/A
	Tier 1 capital (to average assets):
	First Banks, Inc.	283,962			5.02		284,396		5.01		4		N/A		4		N/A
	First Bank	612,837			10.78		642,593		11.35		4		5		4		5
	Regulatory Agreements. On May 19, 2014, the Company entered into an MOU with the FRB. The MOU is characterized by regulatory authorities as an informal action that is neither published nor made publicly available by the FRB and is used when circumstances warrant a milder form of action than a formal supervisory action. Under the terms of the MOU, the Company agreed, among other things, to provide certain information to the FRB including, but not limited to, progress of achieving its Capital Plan, notice of plans to materially change its Capital Plan, parent company cash flow plans and summaries of nonperforming asset classifications. In addition, the Company agreed not to do any of the following without the prior approval of the FRB: (i) declare or pay any dividends on its common or preferred stock; (ii) incur or guarantee any debt; (iii) redeem any of the Company's outstanding common or preferred stock; and (iv) cause First Bank to pay dividends in excess of its earnings or make a capital distribution that would cause First Bank's Tier 1 Leverage Ratio to fall below 9.0%. The FRB has complete discretion to grant any such approval and therefore, it is not known whether the FRB would approve any such request.
	While the Company intends to take such actions as may be necessary to comply with the requirements of the MOU with the FRB, there can be no assurance that such efforts will not have adverse effects on the operations and financial condition of the Company or First Bank. If the Company fails to comply with the terms of the MOU, further enforcement action could be taken by the FRB which could have a materially adverse effect on the Company's business, financial condition or results of operations.

FAIR_VALUE_DISCLOSURES

FAIR VALUE DISCLOSURES	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
FAIR VALUE DISCLOSURES	FAIR VALUE DISCLOSURES
	In accordance with ASC Topic 820, “Fair Value Measurements and Disclosures,” financial assets and financial liabilities that are measured at fair value subsequent to initial recognition are grouped into three levels of inputs or assumptions that market participants would use in pricing the asset or liability, including assumptions about risk and the reliability of assumptions used to determine fair value. The three input levels of the valuation hierarchy are as follows:
	Level 1 Inputs –	Valuation is based on quoted prices in active markets for identical instruments in active markets.
	Level 2 Inputs –	Valuation is based on quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations whose inputs are observable or whose significant value drivers are observable.
	Level 3 Inputs –	Valuation is generated from model-based techniques that use at least one significant assumption not observable in the market. These unobservable assumptions reflect estimates of assumptions that market participants would use in pricing the asset or liability. Valuation techniques include use of option pricing models, discounted cash flow models and similar techniques.
	The following describes valuation methodologies used to measure financial assets and financial liabilities at fair value, as well as the general classification of such financial instruments pursuant to the valuation hierarchy:
	Available-for-sale investment securities. Available-for-sale investment securities are recorded at fair value on a recurring basis. Available-for-sale investment securities included in Level 1 are valued using quoted market prices. Where quoted market prices are unavailable, the fair value included in Level 2 is based on quoted market prices of comparable instruments obtained from independent pricing vendors based on recent trading activity and other relevant information.
	Loans held for sale. Mortgage loans held for sale are carried at fair value on a recurring basis. The determination of fair value is based on quoted market prices of comparable instruments obtained from independent pricing vendors based on recent trading activity and other relevant information. Other loans held for sale are carried at the lower of cost or market value, which is determined on an individual loan basis. The fair value is based on the prices secondary markets are offering for portfolios with similar characteristics. The Company classifies mortgage loans held for sale subjected to recurring fair value adjustments as recurring Level 2. The Company classifies other loans held for sale subjected to nonrecurring fair value adjustments as nonrecurring Level 2.
	Impaired loans. The Company does not record loans at fair value on a recurring basis. However, from time to time, a loan is considered impaired and an allowance for loan losses is established. Loans are considered impaired when, in the judgment of management based on current information and events, it is probable that payment of all amounts due under the contractual terms of the loan agreement will not be collected. In accordance with ASC Topic 820, impaired loans where an allowance is established based on the fair value of collateral require classification in the fair value hierarchy. Once a loan is identified as impaired, management measures the impairment in accordance with ASC Topic 310-10-35, “Receivables.” Impairment is measured by reference to an observable market price, if one exists, the expected future cash flows of an impaired loan discounted at the loan’s effective interest rate, or the fair value of the collateral for a collateral-dependent loan. In most cases, the Company measures fair value based on the value of the collateral securing the loan. Collateral may be in the form of real estate or personal property, including equipment and inventory. The vast majority of the collateral is real estate. The value of the collateral is determined based on third party appraisals as well as internal estimates. These measurements are classified as nonrecurring Level 3.
	Other real estate. Certain other real estate, upon initial recognition, is re-measured and reported at fair value through a charge-off to the allowance for loan losses based upon the estimated fair value of the other real estate. The fair value of other real estate, upon initial recognition, is estimated using Level 3 inputs based on third party appraisals, and where applicable, discounted based on management’s judgment taking into account current market conditions, distressed or forced sale price comparisons and other factors in effect at the time of valuation. The Company classifies other real estate subjected to nonrecurring fair value adjustments as Level 3.
	Derivative instruments. Substantially all derivative instruments utilized by the Company are traded in over-the-counter markets where quoted market prices are not readily available. Derivative instruments utilized by the Company currently include interest rate lock commitments and forward commitments to sell mortgage-backed securities. For these derivative instruments, fair value is based on market observable inputs utilizing pricing systems and valuation models, and where applicable, the values are compared to the market values calculated independently by the respective counterparties. The Company classifies its derivative instruments as Level 2.
	Servicing rights. The valuation of mortgage and SBA servicing rights is performed by an independent third party. The valuation models estimate the present value of estimated future net servicing income, using market-based discount rate assumptions, and utilize assumptions based on the predominant risk characteristics of the underlying loans, including principal balance, interest rate, weighted average life, and certain unobservable inputs, including cost to service, estimated prepayment speed rates and default rates. Changes in the fair value of servicing rights occur primarily due to the realization of expected cash flows, as well as changes in valuation inputs and assumptions. Significant increases (decreases) in any of the unobservable inputs would result in a significantly lower (higher) fair value of the servicing rights. The Company classifies its servicing rights as Level 3.
	Items Measured on a Recurring Basis. Assets and liabilities measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 are reflected in the following table:
		Fair Value Measurements
	(dollars in thousands)	Level 1			Level 2		Level 3	Fair Value
	March 31, 2015:
	Assets:
	Available-for-sale investment securities:
	U.S. Government sponsored agencies	$	—		252,552		—	252,552
	Residential mortgage-backed	—			1,056,256		—	1,056,256
	Commercial mortgage-backed	—			838		—	838
	State and political subdivisions	—			29,194		—	29,194
	Corporate notes	—			213,617		—	213,617
	Equity investments	1,985			—		—	1,985
	Mortgage loans held for sale	—			43,655		—	43,655
	Derivative instruments:
	Interest rate lock commitments	—			1,268		—	1,268
	Forward commitments to sell mortgage-backed securities	—			(284	)	—	(284	)
	Servicing rights	—			—		17,402	17,402
	Total	$	1,985		1,597,096		17,402	1,616,483
	December 31, 2014:
	Assets:
	Available-for-sale investment securities:
	U.S. Government sponsored agencies	$	—		231,731		—	231,731
	Residential mortgage-backed	—			1,007,844		—	1,007,844
	Commercial mortgage-backed	—			837		—	837
	State and political subdivisions	—			29,615		—	29,615
	Corporate notes	—			173,695		—	173,695
	Equity investments	1,967			—		—	1,967
	Mortgage loans held for sale	—			31,411		—	31,411
	Derivative instruments:
	Interest rate lock commitments	—			580		—	580
	Forward commitments to sell mortgage-backed securities	—			(294	)	—	(294	)
	Servicing rights	—			—		18,013	18,013
	Total	$	1,967		1,475,419		18,013	1,495,399
	There were no transfers between Levels 1 and 2 of the fair value hierarchy for the three months ended March 31, 2015 and 2014.
	The following table presents the changes in Level 3 assets measured on a recurring basis for the three months ended March 31, 2015 and 2014:
		Servicing Rights
		Three Months Ended
		March 31,
	(dollars in thousands)	2015			2014
	Balance, beginning of period	$	18,013		18,854
	Total gains or losses (realized/unrealized):
	Included in earnings (1)	(1,472		)	(232	)
	Included in other comprehensive income	—			—
	Issuances	822			455
	Purchases	39			—
	Transfers in and/or out of level 3	—			—
	Balance, end of period	$	17,402		19,077
	____________________
	-1	Gains or losses (realized/unrealized) are included in noninterest income in the consolidated statements of income.
	Items Measured on a Nonrecurring Basis. From time to time, the Company measures certain assets at fair value on a nonrecurring basis. These include assets that are measured at the lower of cost or market value that were recognized at fair value below cost at the end of the period. Assets measured at fair value on a nonrecurring basis as of March 31, 2015 and December 31, 2014 are reflected in the following table:
		Fair Value Measurements
	(dollars in thousands)	Level 1			Level 2		Level 3	Fair Value
March 31, 2015:
Assets:
Impaired loans:
Commercial, financial and agricultural	$	—		—		7,033	7,033
Real estate construction and development	—			—		3,396	3,396
Real estate mortgage:
Residential mortgage	—			—		81,475	81,475
Home equity	—			—		5,070	5,070
Multi-family residential	—			—		17,782	17,782
Commercial real estate	—			—		3,788	3,788
Consumer and installment	—			—		4	4
Other real estate	—			—		15,227	15,227
Total	$	—		—		133,775	133,775
December 31, 2014:
Assets:
Impaired loans:
Commercial, financial and agricultural	$	—		—		8,144	8,144
Real estate construction and development	—			—		3,516	3,516
Real estate mortgage:
Residential mortgage	—			—		82,479	82,479
Home equity	—			—		5,465	5,465
Multi-family residential	—			—		18,574	18,574
Commercial real estate	—			—		7,424	7,424
Consumer and installment	—			—		22	22
Other real estate	—			—		55,666	55,666
Total	$	—		—		181,290	181,290
Non-Financial Assets and Non-Financial Liabilities. Certain non-financial assets measured at fair value on a nonrecurring basis include other real estate (upon initial recognition or subsequent impairment) and other non-financial long-lived assets measured at fair value for impairment assessment.
Other real estate measured at fair value upon initial recognition totaled $459,000 and $1.0 million for the three months ended March 31, 2015 and 2014, respectively. In addition to other real estate measured at fair value upon initial recognition, the Company recorded write-downs to the balance of other real estate of $109,000 and $97,000 to noninterest expense for the three months ended March 31, 2015 and 2014, respectively.
Fair Value of Financial Instruments. The fair value of financial instruments is management’s estimate of the values at which the instruments could be exchanged in a transaction between willing parties. These estimates are subjective and may vary significantly from amounts that would be realized in actual transactions. In addition, other significant assets are not considered financial assets including deferred income tax assets, bank premises and equipment and goodwill. Furthermore, the income taxes that would be incurred if the Company were to realize any of the unrealized gains or unrealized losses indicated between the estimated fair values and corresponding carrying values could have a significant effect on the fair value estimates and have not been considered in any of the estimates. The following summarizes the methods and assumptions used in estimating the fair value of all other financial instruments:
Cash and cash equivalents and accrued interest receivable. The carrying values reported in the consolidated balance sheets approximate fair value.
Held-to-maturity investment securities. The fair value of held-to-maturity investment securities is based on quoted market prices where available. If quoted market prices are not available, the fair value is based on quoted market prices of comparable instruments. The Company classifies its held-to-maturity investment securities as Level 2.
Loans. The fair value of loans held for portfolio uses an exit price concept and reflects discounts the Company believes are consistent with liquidity discounts in the market place. Fair values are estimated for portfolios of loans with similar financial characteristics. Loans are segregated by type such as commercial and industrial, real estate construction and development, commercial real estate, one-to-four-family residential real estate, home equity and consumer and installment. The fair value of loans is estimated by discounting the future cash flows, utilizing assumptions for prepayment estimates over the loans’ remaining life and considerations for the current interest rate environment compared to the weighted average rate of the loan portfolio. The fair value analysis also includes other assumptions to estimate fair value, intended to approximate those factors a market participant would use in an orderly transaction, with adjustments for discount rates, interest rates, liquidity, and credit spreads, as appropriate. The Company classifies its loans held for portfolio as Level 3.
Deposits. The fair value of deposits payable on demand with no stated maturity (i.e., noninterest-bearing and interest-bearing demand, and savings and money market accounts) is considered equal to their respective carrying amounts as reported in the consolidated balance sheets. The fair value of demand deposits does not include the benefit that results from the low-cost funding provided by deposit liabilities compared to the cost of borrowing funds in the market. The fair value disclosed for time deposits is estimated utilizing a discounted cash flow calculation that applies interest rates currently being offered on similar deposits to a schedule of aggregated monthly maturities of time deposits. If the estimated fair value is lower than the carrying value, the carrying value is reported as the fair value of time deposits. The Company classifies its time deposits as Level 3.
Other borrowings and accrued interest payable. The carrying values reported in the consolidated balance sheets for variable rate borrowings approximate fair value. The fair value of fixed rate borrowings is based on quoted market prices where available. If quoted market prices are not available, the fair value is based on discounting contractual maturities using an estimate of current market rates for similar instruments. The Company classifies its other borrowings, comprised of securities sold under agreements to repurchase, as Level 1. The carrying values reported in the consolidated balance sheets for accrued interest payable approximate fair value.
Subordinated debentures. The fair value of subordinated debentures is based on quoted market prices of comparable instruments. The Company classifies its subordinated debentures as Level 3.
Off-Balance Sheet Financial Instruments. The fair value of commitments to extend credit, standby letters of credit and financial guarantees is based on estimated probable credit losses. The Company classifies its off-balance sheet financial instruments as Level 3.
The estimated fair value of the Company’s financial instruments at March 31, 2015 was as follows:
	March 31, 2015
	Carrying			Estimated Fair Value
(dollars in thousands)	Value			Level 1		Level 2	Level 3		Total
Financial Assets:
Cash and cash equivalents	$	230,735		230,735		—	—		230,735
Investment securities:
Available for sale	1,554,442			1,985		1,552,457	—		1,554,442
Held to maturity	595,335			—		597,341	—		597,341
Loans held for portfolio	3,085,600			—		—	3,096,743		3,096,743
Loans held for sale	43,655			—		43,655	—		43,655
Derivative instruments	984			—		984	—		984
Accrued interest receivable	15,867			15,867		—	—		15,867
Financial Liabilities:
Deposits	$	4,972,089		4,049,806		—	921,817		4,971,623
Securities sold under agreements to repurchase	51,032			51,032		—	—		51,032
Accrued interest payable	830			830		—	—		830
Subordinated debentures	354,305			—		—	270,473		270,473
Liability for Off-Balance Sheet Financial Instruments:
Commitments to extend credit, standby letters of credit and financial guarantees	$	12		—		—	12		12
The estimated fair value of the Company’s financial instruments at December 31, 2014 was as follows:
	December 31, 2014
	Carrying			Estimated Fair Value
(dollars in thousands)	Value			Level 1		Level 2	Level 3		Total
Financial Assets:
Cash and cash equivalents	$	205,402		205,402		—	—		205,402
Investment securities:
Available for sale	1,445,689			1,967		1,443,722	—		1,445,689
Held to maturity	618,148			—		614,272	—		614,272
Loans held for portfolio	3,050,958			—		—	2,937,948		2,937,948
Loans held for sale	31,411			—		31,411	—		31,411
Derivative instruments	286			—		286	—		286
Accrued interest receivable	15,064			15,064		—	—		15,064
Financial Liabilities:
Deposits	$	4,849,504		3,923,627		—	924,955		4,848,582
Securities sold under agreements to repurchase	64,875			64,875		—	—		64,875
Accrued interest payable	831			831		—	—		831
Subordinated debentures	354,286			—		—	303,191		303,191
Liability for Off-Balance Sheet Financial Instruments:
Commitments to extend credit, standby letters of credit and financial guarantees	$	12		—		—	12		12

BUSINESS_SEGMENT_RESULTS

BUSINESS SEGMENT RESULTS	3 Months Ended
	Mar. 31, 2015
Segment Reporting [Abstract]
BUSINESS SEGMENT RESULTS	BUSINESS SEGMENT RESULTS
	The Company’s business segment is First Bank. The reportable business segment is consistent with the management structure of the Company, First Bank and the internal reporting system that monitors performance. First Bank provides similar products and services in its defined geographic areas through its branch network. The products and services offered include a broad range of commercial and personal deposit products, including demand, savings, money market and time deposit accounts. In addition, First Bank markets combined basic services for various client groups, including packaged accounts for more affluent clients, and sweep accounts, lock-box deposits and cash management products for commercial clients. First Bank also offers consumer and commercial loans. Consumer lending includes residential real estate, home equity and installment lending. Commercial lending includes commercial, financial and agricultural loans, real estate construction and development loans, commercial real estate loans and small business lending. Other financial services include mortgage banking, debit cards, brokerage services, internet banking, remote deposit, mobile banking, automated teller machine (“ATMs”), telephone banking, safe deposit boxes, and trust and private banking services. The revenues generated by First Bank and its subsidiaries consist primarily of interest income generated from the loan and investment security portfolios, service charges and fees generated from deposit products and services, and fees generated by the Company’s mortgage banking and trust and private banking business units. The Company’s products and services are offered to clients primarily within its geographic areas, which include eastern Missouri, southern Illinois, southern and northern California, and Florida’s Bradenton, Palmetto and Longboat Key communities. Certain loan products are available nationwide.
	The business segment results are consistent with the Company’s internal reporting system and, in all material respects, with GAAP and practices predominant in the banking industry. The business segment results are summarized as follows:
		First Bank				Corporate, Other and				Consolidated Totals
						Intercompany
						Reclassifications
	(dollars in thousands)	March 31,		December 31,		March 31,		December 31,		March 31,	December 31,
		2015		2014		2015		2014		2015	2014
	Balance sheet information:
	Investment securities	$	2,149,777	2,063,837		—		—		2,149,777	2,063,837
	Total loans	3,193,397		3,149,243		—		—		3,193,397	3,149,243
	FRB and FHLB stock	30,348		30,458		—		—		30,348	30,458
	Total assets	5,992,340		5,882,222		54,290		53,297		6,046,630	5,935,519
	Deposits	4,997,353		4,871,140		(25,264	)	(21,636	)	4,972,089	4,849,504
	Securities sold under agreements to repurchase	51,032		64,875		—		—		51,032	64,875
	Subordinated debentures	—		—		354,305		354,286		354,305	354,286
	Stockholders’ equity	872,736		871,301		(353,365	)	(358,857	)	519,371	512,444
		First Bank				Corporate, Other and				Consolidated Totals
						Intercompany
						Reclassifications
		Three Months Ended				Three Months Ended				Three Months Ended
		March 31,				March 31,				March 31,
	(dollars in thousands)	2015		2014		2015		2014		2015	2014
	Income statement information:
	Interest income	$	41,666	42,189		—		—		41,666	42,189
	Interest expense	2,075		2,051		3,004		3,798		5,079	5,849
	Net interest income (loss)	39,591		40,138		(3,004	)	(3,798	)	36,587	36,340
	Provision for loan losses	—		—		—		—		—	—
	Net interest income (loss) after provision for loan losses	39,591		40,138		(3,004	)	(3,798	)	36,587	36,340
	Noninterest income	18,037		14,169		91		116		18,128	14,285
	Noninterest expense	50,243		42,603		176		(245	)	50,419	42,358
	Income (loss) before provision (benefit) for income taxes	7,385		11,704		(3,089	)	(3,437	)	4,296	8,267
	Provision (benefit) for income taxes	2,694		4,120		(1,081	)	(1,203	)	1,613	2,917
	Net income (loss)	4,691		7,584		(2,008	)	(2,234	)	2,683	5,350
	Net income (loss) attributable to noncontrolling interest in subsidiary	9		(55	)	—		—		9	(55	)
	Net income (loss) attributable to First Banks, Inc.	$	4,682	7,639		(2,008	)	(2,234	)	2,674	5,405

TRANSACTIONS_WITH_RELATED_PART

TRANSACTIONS WITH RELATED PARTIES	3 Months Ended
	Mar. 31, 2015
Related Party Transactions [Abstract]
TRANSACTIONS WITH RELATED PARTIES	TRANSACTIONS WITH RELATED PARTIES
	First Services, L.P. First Services, L.P. (“First Services”), a limited partnership indirectly owned by the Company’s Chairman and members of his immediate family, including Mr. Michael Dierberg, Vice Chairman of the Company, and Ms. Ellen Dierberg Milne, Director of the Company, provides information technology, item processing and various related services to the Company and First Bank. Fees charged by First Services to First Bank (net of payments from First Services to First Bank for rental of information technology and other equipment) were $5.0 million and $4.9 million for the three months ended March 31, 2015 and 2014, respectively. In addition, First Services paid $435,000 for the three months ended March 31, 2015 and 2014 in rental payments to First Bank for occupancy of certain First Bank premises from which business is conducted.
	First Services has an Affiliate Services Agreement with the Company and First Bank that relates to various services provided to First Services, including certain human resources, payroll, employee benefit and training services, accounting services, insurance services, vendor payment processing services and advisory services. Fees incurred under the Affiliate Services Agreement by First Services were $54,000 and $60,000 for the three months ended March 31, 2015 and 2014, respectively.
	First Brokerage America, L.L.C. First Brokerage America, L.L.C. (“First Brokerage”), a limited liability company indirectly owned by the Company’s Chairman and members of his immediate family, including Mr. Michael Dierberg, Vice Chairman of the Company, and Ms. Ellen Dierberg Milne, Director of the Company, received approximately $1.0 million for the three months ended March 31, 2015 and 2014, respectively, in gross commissions paid by unaffiliated third-party companies. The commissions received primarily resulted from sales of annuities, securities and other insurance products to clients of First Bank. First Brokerage paid approximately $117,000 and $93,000 for the three months ended March 31, 2015 and 2014, respectively, to First Bank in rental payments for occupancy of certain First Bank premises from which brokerage business is conducted.
	Dierbergs Markets, Inc. First Bank leases certain of its in-store branch offices and ATM sites from Dierbergs Markets, Inc., a grocery store chain headquartered in St. Louis, Missouri that is owned and operated by the brother of the Company’s Chairman and members of his immediate family. Total rent expense incurred by First Bank under the lease obligation contracts was $128,000 and $126,000 for the three months ended March 31, 2015 and 2014, respectively.
	First Capital America, Inc. / FB Holdings, LLC. The Company formed FB Holdings, a limited liability company organized in the state of Missouri, in May 2008. FB Holdings operates as a majority-owned subsidiary of First Bank and was formed for the primary purpose of holding and managing certain nonperforming loans and assets and to permit an efficient vehicle for the investment of additional capital by the Company’s sole owner of its Class A and Class B preferred stock. First Bank owned 53.23% and FCA, a corporation owned by the Company’s Chairman and members of his immediate family, including Mr. Michael Dierberg, Vice Chairman of the Company, and Ms. Ellen Dierberg Milne, Director of the Company, owned the remaining 46.77% of FB Holdings as of March 31, 2015. FCA’s ownership in FB Holdings is reflected as a component of stockholders’ equity in the consolidated balance sheets.
	Loans to Directors, Executive Officers and/or their Affiliates. First Bank has had in the past, and may have in the future, loan transactions in the ordinary course of business with its directors, executive officers and/or their affiliates. Loans to directors, their affiliates and executive officers of the Company were $9.2 million and $28.8 million at March 31, 2015 and December 31, 2014, respectively. First Bank does not extend credit to its officers or to officers of the Company, except extensions of credit secured by mortgages on personal residences, loans to purchase automobiles, personal credit card accounts and deposit account overdraft protection under a plan whereby a credit limit has been established in accordance with First Bank’s standard credit criteria.
	Depositary Accounts of Directors, Executive Officers and/or their Affiliates. Certain directors, executive officers and/or their affiliates maintain funds on deposit with First Bank in the ordinary course of business. These deposit transactions include demand, savings and time accounts, and have been established on the same terms, including interest rates, as those prevailing at the time for comparable transactions with unaffiliated persons.

CONTINGENT_LIABILITIES

CONTINGENT LIABILITIES	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
CONTINGENT LIABILITIES	CONTINGENT LIABILITIES
	Litigation Matters. In the ordinary course of business, the Company and its subsidiaries become involved in legal proceedings, including litigation arising out of the Company’s efforts to collect outstanding loans. It is not uncommon for collection efforts to lead to so-called “lender liability” suits in which borrowers may assert various claims against the Company. From time to time, the Company is party to other legal matters arising in the normal course of business. While some matters pending against the Company specify damages claimed by plaintiffs, others do not seek a specified amount of damages or are at very early stages of the legal process. The Company records a loss accrual for all legal matters for which it deems a loss is probable and can be reasonably estimated. Management, after consultation with legal counsel, believes the ultimate resolution of these existing proceedings is not reasonably likely to have a material adverse effect on the business, financial condition or results of operations of the Company and/or its subsidiaries and the range of possible additional loss in excess of amounts accrued is not material.
	Regulatory Matters. The Company entered into an MOU with the FRB, dated May 19, 2014. This agreement is further described in Note 8 to the consolidated financial statements.

BASIS_OF_PRESENTATION_Policies

BASIS OF PRESENTATION (Policies)	3 Months Ended
	Mar. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Accounting	The consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and conform to predominant practices within the banking industry. Certain disclosures pertaining to companies whose common stock is not publicly traded have been omitted from the Company’s financial statements in accordance with GAAP requirements. Management of the Company has made a number of estimates and assumptions relating to the reporting of assets and liabilities and the disclosure of contingent assets and liabilities to prepare the consolidated financial statements in conformity with GAAP. Actual results could differ from those estimates.
Principals of Consolidation	Principles of Consolidation. The consolidated financial statements include the accounts of the parent company and its subsidiaries, giving effect to the noncontrolling interest in subsidiary, as more fully described below and in Note 11 to the consolidated financial statements. All significant intercompany accounts and transactions have been eliminated.
	The Company operates through its wholly owned subsidiary bank holding company, The San Francisco Company (“SFC”), headquartered in St. Louis, Missouri, and SFC’s wholly owned subsidiary bank, First Bank, also headquartered in St. Louis, Missouri. First Bank operates through its branch banking offices and subsidiaries. All of the subsidiaries are wholly owned as of March 31, 2015 except FB Holdings, LLC (“FB Holdings”), which is 53.23% owned by First Bank and 46.77% owned by First Capital America, Inc. (“FCA”), a corporation owned and operated by the Company’s Chairman of the Board and members of his immediate family, including Mr. Michael Dierberg, Vice Chairman of the Company, and Ms. Ellen Dierberg Milne, Director of the Company, as further described in Note 11 to the consolidated financial statements. FB Holdings is included in the consolidated financial statements and the noncontrolling ownership interest is reported as a component of stockholders’ equity in the consolidated balance sheets as “noncontrolling interest in subsidiary” and the earnings or loss, net of tax, attributable to the noncontrolling ownership interest, is reported as “net income (loss) attributable to noncontrolling interest in subsidiary” in the consolidated statements of income.

INVESTMENTS_IN_DEBT_AND_EQUITY1

INVESTMENTS IN DEBT AND EQUITY SECURITIES (Tables)	3 Months Ended
	Mar. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Available-for-sale Securities [Table Text Block]	The amortized cost, contractual maturity, gross unrealized gains and losses and fair value of investment securities available for sale at March 31, 2015 and December 31, 2014 were as follows:
		Maturity									Total Amortized Cost	Gross					Weighted Average Yield
		1 Year			5-Jan		10-May		After			Unrealized				Fair
	(dollars in thousands)	or Less			Years		Years		10 Years			Gains		Losses		Value
	March 31, 2015:
	Carrying value:
	U.S. Government sponsored agencies	$	—		29,904		20,114		201,168		251,186	2,093		(727	)	252,552	1.45	%
	Residential mortgage-backed	—			65,101		79,250		895,399		1,039,750	18,814		(2,308	)	1,056,256	2.38
	Commercial mortgage-backed	—			775		—		—		775	63		—		838	4.95
	State and political subdivisions	511			569		—		28,356		29,436	26		(268	)	29,194	1.04
	Corporate notes	38,640			67,069		81,388		24,449		211,546	2,870		(799	)	213,617	2.55
	Equity investments	—			—		—		2,000		2,000	—		(15	)	1,985	2.14
	Total	$	39,151		163,418		180,752		1,151,372		1,534,693	23,866		(4,117	)	1,554,442	2.23
	Fair value:
	Debt securities	$	39,606		166,357		184,307		1,162,187
	Equity securities	—			—		—		1,985
	Total	$	39,606		166,357		184,307		1,164,172
	Weighted average yield	2.57		%	1.96	%	2.58	%	2.2	%
	December 31, 2014:
	Carrying value:
	U.S. Government sponsored agencies	$	—		29,942		20,119		180,098		230,159	2,129		(557	)	231,731	1.39	%
	Residential mortgage-backed	269			65,433		48,174		885,896		999,772	14,189		(6,117	)	1,007,844	2.39
	Commercial mortgage-backed	—			779		—		—		779	58		—		837	4.95
	State and political subdivisions	863			571		—		28,371		29,805	33		(223	)	29,615	1.05
	Corporate notes	27,382			72,959		70,990		—		171,331	2,759		(395	)	173,695	2.75
	Equity investments	—			—		—		2,000		2,000	—		(33	)	1,967	2.15
	Total	$	28,514		169,684		139,283		1,096,365		1,433,846	19,168		(7,325	)	1,445,689	2.25
	Fair value:
	Debt securities	$	28,901		172,561		140,717		1,101,543
	Equity securities	—			—		—		1,967
	Total	$	28,901		172,561		140,717		1,103,510
	Weighted average yield	2.64		%	1.97	%	2.58	%	2.23	%
Held-to-maturity Securities [Table Text Block]	The amortized cost, contractual maturity, gross unrealized gains and losses and fair value of investment securities held to maturity at March 31, 2015 and December 31, 2014 were as follows:
		Maturity									Total Amortized Cost	Gross					Weighted Average Yield
		1 Year			5-Jan		10-May		After			Unrealized				Fair
	(dollars in thousands)	or Less			Years		Years		10 Years			Gains		Losses		Value
	March 31, 2015:
	Carrying value:
	U.S. Government sponsored agencies	$	—		—		10,001		—		10,001	64		—		10,065	1.29	%
	Residential mortgage-backed	—			103,224		48,400		429,339		580,963	4,013		(1,984	)	582,992	1.89
	State and political subdivisions	561			660		2,189		961		4,371	1		(88	)	4,284	1.78
	Total	$	561		103,884		60,590		430,300		595,335	4,078		(2,072	)	597,341	1.88
	Fair value:
	Debt securities	$	561		104,797		61,100		430,883
	Weighted average yield	3.07		%	1.93	%	1.25	%	1.95	%
	December 31, 2014:
	Carrying value:
	U.S. Government sponsored agencies	$	—		—		10,725		—		10,725	42		—		10,767	1.25	%
	Residential mortgage-backed	—			105,660		50,512		448,905		605,077	1,931		(5,782	)	601,226	1.86
	State and political subdivisions	561			335		489		961		2,346	1		(68	)	2,279	1.68
	Total	$	561		105,995		61,726		449,866		618,148	1,974		(5,850	)	614,272	1.85
	Fair value:
	Debt securities	$	561		106,147		62,000		445,564
	Weighted average yield	3.07		%	1.88	%	1.13	%	1.94	%
Schedule of Realized Gain (Loss) [Table Text Block]	Gross realized gains and gross realized losses on investment securities for the three months ended March 31, 2015 and 2014 were as follows:
		Three Months Ended
		March 31,
	(dollars in thousands)	2015			2014
	Gross realized gains on sales of available-for-sale securities	$	560		2,010
	Gross realized losses on sales of available-for-sale securities	(517		)	(730	)
	Net realized gain on investment securities	$	43		1,280
Schedule of Unrealized Loss on Investments [Table Text Block]	Gross unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at March 31, 2015 and December 31, 2014, were as follows:
		Less Than 12 Months					12 Months or More				Total
	(dollars in thousands)	Fair Value			Unrealized		Fair Value		Unrealized		Fair Value	Unrealized
					Losses				Losses			Losses
	March 31, 2015:
	Available for sale:
	U.S. Government sponsored agencies	$	86,684		(592	)	14,600		(135	)	101,284	(727	)
	Residential mortgage-backed	66,185			(252	)	117,535		(2,056	)	183,720	(2,308	)
	State and political subdivisions	28,087			(268	)	—		—		28,087	(268	)
	Corporate notes	20,274			(756	)	4,957		(43	)	25,231	(799	)
	Equity investments	1,985			(15	)	—		—		1,985	(15	)
	Total	$	203,215		(1,883	)	137,092		(2,234	)	340,307	(4,117	)
	Held to maturity:
	Residential mortgage-backed	$	100,000		(386	)	119,905		(1,598	)	219,905	(1,984	)
	State and political subdivisions	2,643			(27	)	899		(61	)	3,542	(88	)
	Total	$	102,643		(413	)	120,804		(1,659	)	223,447	(2,072	)
	December 31, 2014:
	Available for sale:
	U.S. Government sponsored agencies	$	79,207		(427	)	14,600		(130	)	93,807	(557	)
	Residential mortgage-backed	204,378			(1,154	)	191,644		(4,963	)	396,022	(6,117	)
	State and political subdivisions	28,148			(223	)	—		—		28,148	(223	)
	Corporate notes	9,650			(350	)	4,955		(45	)	14,605	(395	)
	Equity investments	1,967			(33	)	—		—		1,967	(33	)
	Total	$	323,350		(2,187	)	211,199		(5,138	)	534,549	(7,325	)
	Held to maturity:
	Residential mortgage-backed	$	28,371		(112	)	325,820		(5,670	)	354,191	(5,782	)
	State and political subdivisions	641			(3	)	896		(65	)	1,537	(68	)
	Total	$	29,012		(115	)	326,716		(5,735	)	355,728	(5,850	)

LOANS_AND_ALLOWANCE_FOR_LOAN_L1

LOANS AND ALLOWANCE FOR LOAN LOSSES (Tables)	3 Months Ended
	Mar. 31, 2015
Receivables [Abstract]
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]	The following table summarizes the composition of the loan portfolio at March 31, 2015 and December 31, 2014:
	(dollars in thousands)	March 31,				December 31,
		2015				2014
	Commercial, financial and agricultural	$	700,183			695,267
	Real estate construction and development	110,705				89,851
	Real estate mortgage:
	One-to-four-family residential	1,030,088				1,016,710
	Multi-family residential	114,288				115,434
	Commercial real estate	1,174,799				1,183,042
	Consumer and installment	20,956				18,950
	Net deferred loan fees	(1,277		)		(1,422	)
	Total loans held for portfolio	3,149,742				3,117,832
	Loans held for sale	43,655				31,411
	Total loans	$	3,193,397			3,149,243
Past Due Financing Receivables [Table Text Block]	The following table presents the aging of loans by loan classification at March 31, 2015 and December 31, 2014:
	(dollars in thousands)	30-59				60-89			Recorded			Nonaccrual			Total Past		Current		Total Loans
		Days				Days			Investment						Due
									> 90 Days
									Accruing
	March 31, 2015:
	Commercial, financial and agricultural	$	59			227			—			7,240			7,526		692,657		700,183
	Real estate construction and development	781				102			—			3,308			4,191		106,514		110,705
	Real estate mortgage:
	Residential mortgage	3,014				952			15			10,911			14,892		613,181		628,073
	Home equity	810				374			—			6,337			7,521		394,494		402,015
	Multi-family residential	—				—			—			18,994			18,994		95,294		114,288
	Commercial real estate	1,201				32			—			4,046			5,279		1,169,520		1,174,799
	Consumer and installment and net deferred loan fees	100				18			—			4			122		19,557		19,679
	Loans held for sale	—				—			—			—			—		43,655		43,655
	Total	$	5,965			1,705			15			50,840			58,525		3,134,872		3,193,397
	December 31, 2014:
	Commercial, financial and agricultural	$	132			430			54			9,486			10,102		685,165		695,267
	Real estate construction and development	431				—			—			3,393			3,824		86,027		89,851
	Real estate mortgage:
	Residential mortgage	2,690				986			35			13,890			17,601		603,567		621,168
	Home equity	1,857				334			72			6,831			9,094		386,448		395,542
	Multi-family residential	—				—			—			19,731			19,731		95,703		115,434
	Commercial real estate	196				54			—			4,122			4,372		1,178,670		1,183,042
	Consumer and installment and net deferred loan fees	136				33			2			23			194		17,334		17,528
	Loans held for sale	—				—			—			—			—		31,411		31,411
	Total	$	5,442			1,837			163			57,476			64,918		3,084,325		3,149,243
Financing Receivable Credit Quality Indicators [Table Text Block]	The following tables present the credit exposure of the loan portfolio by internally assigned credit grade and payment activity as of March 31, 2015 and December 31, 2014:
	Commercial Loan Portfolio	Commercial				Real Estate			Multi-family			Commercial			Total
	Credit Exposure by Internally Assigned Credit Grade	and				Construction						Real Estate
	(dollars in thousands)	Industrial				and
						Development
	March 31, 2015:
	Pass	$	663,849			106,986			88,787			1,145,244			2,004,866
	Special mention	16,359				92			5,870			17,700			40,021
	Substandard	12,463				—			637			7,809			20,909
	Performing troubled debt restructuring	272				319			—			—			591
	Nonaccrual	7,240				3,308			18,994			4,046			33,588
	Total	$	700,183			110,705			114,288			1,174,799			2,099,975
	December 31, 2014:
	Pass	$	653,951			85,973			89,148			1,147,824			1,976,896
	Special mention	18,713				143			5,945			20,691			45,492
	Substandard	12,833				—			610			6,640			20,083
	Performing troubled debt restructuring	284				342			—			3,765			4,391
	Nonaccrual	9,486				3,393			19,731			4,122			36,732
	Total	$	695,267			89,851			115,434			1,183,042			2,083,594
	Consumer Loan Portfolio	Residential Mortgage				Home			Consumer and Installment and Net Deferred Loan Fees			Total
	Credit Exposure by Payment Activity					Equity
	(dollars in thousands)
	March 31, 2015:
	Pass	$	537,729			394,494			19,557			951,780
	Substandard	1,893				1,184			118			3,195
	Performing troubled debt restructuring	77,540				—			—			77,540
	Nonaccrual	10,911				6,337			4			17,252
	Total	$	628,073			402,015			19,679			1,049,767
	December 31, 2014:
	Pass	$	528,388			386,448			17,334			932,170
	Substandard	2,662				2,263			171			5,096
	Performing troubled debt restructuring	76,228				—			—			76,228
	Nonaccrual	13,890				6,831			23			20,744
	Total	$	621,168			395,542			17,528			1,034,238
Impaired Financing Receivables [Table Text Block]	The following tables present the recorded investment, unpaid principal balance, related allowance for loan losses, average recorded investment and interest income recognized while on impaired status for impaired loans without a related allowance for loan losses and for impaired loans with a related allowance for loan losses by loan classification at March 31, 2015 and December 31, 2014:
	(dollars in thousands)	Recorded				Unpaid			Related			Average			Interest
		Investment				Principal			Allowance for			Recorded			Income
						Balance			Loan Losses			Investment			Recognized
	March 31, 2015:
	With No Related Allowance Recorded:
	Commercial, financial and agricultural	$	2,505			3,401			—			2,881			—
	Real estate construction and development	2,622				12,318			—			2,661			—
	Real estate mortgage:
	Residential mortgage	—				—			—			—			—
	Home equity	—				—			—			—			—
	Multi-family residential	18,675				24,647			—			19,038			—
	Commercial real estate	—				—			—			—			—
	Consumer and installment	—				—			—			—			—
		23,802				40,366			—			24,580			—
	With A Related Allowance Recorded:
	Commercial, financial and agricultural	5,007				7,754			479			5,760			3
	Real estate construction and development	1,005				3,259			231			1,020			4
	Real estate mortgage:
	Residential mortgage	88,451				104,415			6,976			89,285			521
	Home equity	6,337				7,487			1,267			6,584			—
	Multi-family residential	319				3,185			1,212			325			—
	Commercial real estate	4,046				5,813			258			5,967			—
	Consumer and installment	4				4			—			14			5
		105,169				131,917			10,423			108,955			533
	Total:
	Commercial, financial and agricultural	7,512				11,155			479			8,641			3
	Real estate construction and development	3,627				15,577			231			3,681			4
	Real estate mortgage:
	Residential mortgage	88,451				104,415			6,976			89,285			521
	Home equity	6,337				7,487			1,267			6,584			—
	Multi-family residential	18,994				27,832			1,212			19,363			—
	Commercial real estate	4,046				5,813			258			5,967			—
	Consumer and installment	4				4			—			14			5
		$	128,971			172,283			10,423			133,535			533
	(dollars in thousands)	Recorded				Unpaid			Related			Average			Interest
		Investment				Principal			Allowance for			Recorded			Income
						Balance			Loan Losses			Investment			Recognized
	December 31, 2014:
	With No Related Allowance Recorded:
	Commercial, financial and agricultural	$	1,937			2,911			—			2,278			—
	Real estate construction and development	2,626				12,333			—			3,106			—
	Real estate mortgage:
	Residential mortgage	—				—			—			—			—
	Home equity	—				—			—			—			—
	Multi-family residential	19,050				24,759			—			25,234			959
	Commercial real estate	4,119				4,190			—			6,063			116
	Consumer and installment	—				—			—			—			—
		27,732				44,193			—			36,681			1,075
	With A Related Allowance Recorded:
	Commercial, financial and agricultural	7,833				22,089			1,626			9,212			6
	Real estate construction and development	1,109				3,403			219			1,312			17
	Real estate mortgage:
	Residential mortgage	90,118				106,163			7,639			94,835			2,082
	Home equity	6,831				7,988			1,366			7,056			—
	Multi-family residential	681				3,581			1,157			902			—
	Commercial real estate	3,768				5,619			463			5,546			21
	Consumer and installment	23				23			1			14			—
		110,363				148,866			12,471			118,877			2,126
	Total:
	Commercial, financial and agricultural	9,770				25,000			1,626			11,490			6
	Real estate construction and development	3,735				15,736			219			4,418			17
	Real estate mortgage:
	Residential mortgage	90,118				106,163			7,639			94,835			2,082
Home equity	6,831				7,988			1,366			7,056			—
Multi-family residential	19,731				28,340			1,157			26,136			959
Commercial real estate	7,887				9,809			463			11,609			137
Consumer and installment	23				23			1			14			—
	$	138,095			193,059			12,471			155,558			3,201
Troubled Debt Restructurings On Performing Financing Receivables [Table Text Block]	The following table presents the categories of performing TDRs as of March 31, 2015 and December 31, 2014:
	(dollars in thousands)	March 31,				December 31,
		2015				2014
	Performing Troubled Debt Restructurings:
	Commercial, financial and agricultural	$	272			284
	Real estate construction and development	319				342
	Real estate mortgage:
	One-to-four-family residential	77,540				76,228
	Commercial real estate	—				3,765
	Total performing troubled debt restructurings	$	78,131			80,619
Troubled Debt Restructurings On Nonperforming Financing Receivables [Table Text Block]	The following table presents the categories of loans considered nonperforming TDRs as of March 31, 2015 and December 31, 2014:
	(dollars in thousands)	March 31,				December 31,
		2015				2014
	Nonperforming Troubled Debt Restructurings:
	Commercial, financial and agricultural	$	35			243
	Real estate construction and development	2,784				2,788
	Real estate mortgage:
	One-to-four-family residential	3,378				4,003
	Multi-family residential	18,676				19,050
	Commercial real estate	371				371
	Total nonperforming troubled debt restructurings	$	25,244			26,455
Troubled Debt Restructurings on Financing Receivables [Table Text Block]	The following table presents loans classified as TDRs that were modified during the three months ended March 31, 2015 and 2014:
		Three Months Ended March 31, 2015										Three Months Ended March 31, 2014
	(dollars in thousands)	Number		Pre-				Post-				Number		Pre-			Post-
		of		Modification				Modification				of		Modification			Modification
		Contracts		Outstanding				Outstanding				Contracts		Outstanding			Outstanding
				Recorded				Recorded						Recorded			Recorded
				Investment				Investment						Investment			Investment
	Loan Modifications Classified as Troubled Debt Restructurings:
	Real estate mortgage:
	One-to-four-family residential	6		$	1,723			$	1,640			15		$	2,580		$	2,157
Troubled Debt Restructurings That Subsequently Defaulted On Financing Receivables [Table Text Block]	The following table presents TDRs that defaulted within 12 months of modification during the three months ended March 31, 2015 and 2014:
		Three Months Ended						Three Months Ended
		March 31, 2015						March 31, 2014
	(dollars in thousands)	Number of		Recorded				Number of		Recorded
		Contracts		Investment				Contracts		Investment
	Troubled Debt Restructurings That Subsequently Defaulted:
	Real estate mortgage:
	One-to-four-family residential	—		$	—			1		$	438
Allowance for Credit Losses on Financing Receivables [Table Text Block]	The following table represents a summary of changes in the allowance for loan losses by portfolio segment for the three months ended March 31, 2015 and 2014:
	(dollars in thousands)	Commercial				Real Estate			One-to-			Multi-			Commercial		Consumer		Total
		and				Construction			Four-Family			Family			Real Estate		and
		Industrial				and			Residential			Residential					Installment
						Development
	Three Months Ended March 31, 2015:
	Allowance for loan losses:
	Beginning balance	$	12,574			3,490			24,055			5,630			20,983		142		66,874
	Charge-offs	(2,987		)		(40	)		(1,163	)		(189	)		(343	)	(22	)	(4,744	)
	Recoveries	1,244				164			500			56			21		27		2,012
	Provision (benefit) for loan losses	1,501				(860	)		(906	)		77			225		(37	)	—
	Ending balance	$	12,332			2,754			22,486			5,574			20,886		110		64,142
	Three Months Ended March 31, 2014:
	Allowance for loan losses:
	Beginning balance	$	13,401			7,407			32,619			5,249			22,052		305		81,033
	Charge-offs	(1,622		)		(30	)		(1,426	)		(132	)		(188	)	(49	)	(3,447	)
	Recoveries	752				600			791			7			57		38		2,245
	Provision (benefit) for loan losses	1,340				(891	)		(764	)		145			122		48		—
	Ending balance	$	13,871			7,086			31,220			5,269			22,043		342		79,831
Impairment Method by Loan Category [Table Text Block]	The following table represents a summary of the impairment method used by loan category at March 31, 2015 and December 31, 2014:
	(dollars in thousands)	Commercial				Real Estate			One-to-			Multi-			Commercial		Consumer		Total
		and				Construction			Four-Family			Family			Real Estate		and
		Industrial				and			Residential			Residential					Installment and Net Deferred Loan Fees
						Development
	March 31, 2015:
	Allowance for loan losses:
	Impaired loans individually evaluated for impairment	$	—			—			918			—			—		—		918
	Impaired loans collectively evaluated for impairment	479				231			7,325			1,212			258		—		9,505
	All other loans collectively evaluated for impairment	11,853				2,523			14,243			4,362			20,628		110		53,719
	Total allowance for loan losses	$	12,332			2,754			22,486			5,574			20,886		110		64,142
	Loans:
	Impaired loans individually evaluated for impairment	$	2,505			2,622			6,899			18,676			—		—		30,702
	Impaired loans collectively evaluated for impairment	5,007				1,005			87,889			318			4,046		4		98,269
	All other loans collectively evaluated for impairment	692,671				107,078			935,300			95,294			1,170,753		19,675		3,020,771
	Total loans	$	700,183			110,705			1,030,088			114,288			1,174,799		19,679		3,149,742
	December 31, 2014:
	Allowance for loan losses:
	Impaired loans individually evaluated for impairment	$	1,053			—			1,184			—			—		—		2,237
	Impaired loans collectively evaluated for impairment	573				219			7,821			1,157			463		1		10,234
	All other loans collectively evaluated for impairment	10,948				3,271			15,050			4,473			20,520		141		54,403
	Total allowance for loan losses	$	12,574			3,490			24,055			5,630			20,983		142		66,874
	Loans:
	Impaired loans individually evaluated for impairment	$	4,712			2,626			7,388			19,050			3,765		—		37,541
	Impaired loans collectively evaluated for impairment	5,058				1,109			89,561			681			4,122		23		100,554
	All other loans collectively evaluated for impairment	685,497				86,116			919,761			95,703			1,175,155		17,505		2,979,737
	Total loans	$	695,267			89,851			1,016,710			115,434			1,183,042		17,528		3,117,832

SERVICING_RIGHTS_Tables

SERVICING RIGHTS (Tables)	3 Months Ended
	Mar. 31, 2015
Mortgage Banking [Member]
Servicing Assets at Fair Value [Line Items]
Schedule of Servicing Assets at Fair Value [Table Text Block]	Changes in mortgage servicing rights for the three months ended March 31, 2015 and 2014 were as follows:
		Three Months Ended
		March 31,
	(dollars in thousands)	2015			2014
	Balance, beginning of period	$	14,012		14,211
	Originated mortgage servicing rights	822			455
	Purchased mortgage servicing rights	39			—
	Change in fair value resulting from changes in valuation inputs or assumptions used in valuation model (1)	(831		)	151
	Other changes in fair value (2)	(561		)	(422	)
	Balance, end of period	$	13,481		14,395
	____________________
	-1	The change in fair value resulting from changes in valuation inputs or assumptions used in valuation model primarily reflects the change in discount rates and prepayment speed assumptions, primarily due to changes in interest rates.
	-2	Other changes in fair value reflect changes due to the collection/realization of expected cash flows over time.
SBA [Member]
Servicing Assets at Fair Value [Line Items]
Schedule of Servicing Assets at Fair Value [Table Text Block]	Changes in SBA servicing rights for the three months ended March 31, 2015 and 2014 were as follows:
		Three Months Ended
		March 31,
	(dollars in thousands)	2015			2014
	Balance, beginning of period	$	4,001		4,643
	Originated SBA servicing rights	—			—
	Change in fair value resulting from changes in valuation inputs or assumptions used in valuation model (1)	133			175
	Other changes in fair value (2)	(213		)	(136	)
	Balance, end of period	$	3,921		4,682
	____________________
	-1	The change in fair value resulting from changes in valuation inputs or assumptions used in valuation model primarily reflects the change in discount rates and prepayment speed assumptions, primarily due to changes in interest rates.
	-2	Other changes in fair value reflect changes due to the collection/realization of expected cash flows over time.

DERIVATIVE_INSTRUMENTS_Tables

DERIVATIVE INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments [Table Text Block]	The following table summarizes derivative instruments held by the Company, their notional amount, estimated fair values and their location in the consolidated balance sheets at March 31, 2015 and December 31, 2014:
	(dollars in thousands)					Derivatives in Other Assets
		Notional Amount				Fair Value Gain (Loss)
		March 31,			December 31, 2014	March 31,		December 31, 2014
		2015				2015
	Derivative Instruments Not Designated as Hedging Instruments:
	Interest rate lock commitments	$	43,610		20,762	1,268		580
	Forward commitments to sell mortgage-backed securities	71,600			38,300	(284	)	(294	)
	Total	$	115,210		59,062	984		286
Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Table Text Block]	The following table summarizes amounts included in the consolidated statements of income for the three months ended March 31, 2015 and 2014 related to non-hedging derivative instruments:
	(dollars in thousands)		Location of Gain (Loss) Recognized	Amount of Gain (Loss) Recognized
			in Operations on Derivatives	in Operations on Derivatives
				Three Months Ended
				March 31,
				2015		2014
	Derivative Instruments Not Designated as Hedging Instruments:
	Interest rate lock commitments		Gain on loans sold and held for sale	$	688	115
	Forward commitments to sell mortgage-backed securities		Gain on loans sold and held for sale	10		(282	)

STOCKHOLDERS_EQUITY_Tables

STOCKHOLDERS' EQUITY (Tables)	3 Months Ended
	Mar. 31, 2015
Stockholders' Equity Note [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	Accumulated Other Comprehensive Income (Loss). The following table summarizes changes in accumulated other comprehensive income (loss), net of tax, by component, for the three months ended March 31, 2015 and 2014:
	(dollars in thousands)	Investment Securities			Defined Benefit Pension Plan		Total
	Three Months Ended March 31, 2015:
	Balance, beginning of period	$	14,051		(3,940	)	10,111
	Other comprehensive income before reclassifications	4,237			—		4,237
	Amounts reclassified from accumulated other comprehensive income	(25		)	32		7
	Net current period other comprehensive income	4,212			32		4,244
	Balance, end of period	$	18,263		(3,908	)	14,355
	Three Months Ended March 31, 2014:
	Balance, beginning of period	$	10,151		(2,649	)	7,502
	Other comprehensive income before reclassifications	4,432			—		4,432
	Amounts reclassified from accumulated other comprehensive income	(753		)	21		(732	)
	Net current period other comprehensive income	3,679			21		3,700
	Balance, end of period	$	13,830		(2,628	)	11,202

REGULATORY_CAPITAL_AND_OTHER_R1

REGULATORY CAPITAL AND OTHER REGULATORY MATTERS (Tables)	3 Months Ended
	Mar. 31, 2015
Banking and Thrift [Abstract]
Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block]	At March 31, 2015 and December 31, 2014, the Company’s and First Bank’s required and actual capital ratios were as follows:
											Final Capital Rules				General Risk-Based
											(Effective January 1, 2015)				Capital Rules
															(Prior to January 1, 2015)
													To be Well				To be Well
		Actual									For Capital Adequacy Purposes		Capitalized		For Capital Adequacy Purposes		Capitalized
		March 31, 2015					December 31, 2014						Under Prompt Corrective Action Provisions				Under Prompt Corrective Action Provisions
	(dollars in thousands)	Amount			Ratio		Amount		Ratio
	Total capital (to risk-weighted assets):
	First Banks, Inc.	$	582,115		14.88	%	$	475,312	12.25	%	8	%	N/A		8	%	N/A
	First Bank	660,631			16.8		691,350		17.81		8		10	%	8		10	%
	Tier 1 capital (to risk-weighted assets):
	First Banks, Inc.	283,962			7.26		284,396		7.33		6		N/A		4		N/A
	First Bank	612,837			15.59		642,593		16.55		6		8		4		6
	Common equity Tier 1 capital (to risk-weighted assets):
	First Banks, Inc.	(44,624		)	(1.14	)	N/A		N/A		4.5		N/A		N/A		N/A
	First Bank	612,837			15.59		N/A		N/A		4.5		6.5		N/A		N/A
	Tier 1 capital (to average assets):
	First Banks, Inc.	283,962			5.02		284,396		5.01		4		N/A		4		N/A
	First Bank	612,837			10.78		642,593		11.35		4		5		4		5

FAIR_VALUE_DISCLOSURES_Tables

FAIR VALUE DISCLOSURES (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	Assets and liabilities measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 are reflected in the following table:
		Fair Value Measurements
	(dollars in thousands)	Level 1			Level 2		Level 3	Fair Value
	March 31, 2015:
	Assets:
	Available-for-sale investment securities:
	U.S. Government sponsored agencies	$	—		252,552		—	252,552
	Residential mortgage-backed	—			1,056,256		—	1,056,256
	Commercial mortgage-backed	—			838		—	838
	State and political subdivisions	—			29,194		—	29,194
	Corporate notes	—			213,617		—	213,617
	Equity investments	1,985			—		—	1,985
	Mortgage loans held for sale	—			43,655		—	43,655
	Derivative instruments:
	Interest rate lock commitments	—			1,268		—	1,268
	Forward commitments to sell mortgage-backed securities	—			(284	)	—	(284	)
	Servicing rights	—			—		17,402	17,402
	Total	$	1,985		1,597,096		17,402	1,616,483
	December 31, 2014:
	Assets:
	Available-for-sale investment securities:
	U.S. Government sponsored agencies	$	—		231,731		—	231,731
	Residential mortgage-backed	—			1,007,844		—	1,007,844
	Commercial mortgage-backed	—			837		—	837
	State and political subdivisions	—			29,615		—	29,615
	Corporate notes	—			173,695		—	173,695
	Equity investments	1,967			—		—	1,967
	Mortgage loans held for sale	—			31,411		—	31,411
	Derivative instruments:
	Interest rate lock commitments	—			580		—	580
	Forward commitments to sell mortgage-backed securities	—			(294	)	—	(294	)
	Servicing rights	—			—		18,013	18,013
	Total	$	1,967		1,475,419		18,013	1,495,399
Schedule Of Servicing Assets At Fair Value Measured At Level 3 On Recurring Basis [Table Text Block]	The following table presents the changes in Level 3 assets measured on a recurring basis for the three months ended March 31, 2015 and 2014:
		Servicing Rights
		Three Months Ended
		March 31,
	(dollars in thousands)	2015			2014
	Balance, beginning of period	$	18,013		18,854
	Total gains or losses (realized/unrealized):
	Included in earnings (1)	(1,472		)	(232	)
	Included in other comprehensive income	—			—
	Issuances	822			455
	Purchases	39			—
	Transfers in and/or out of level 3	—			—
	Balance, end of period	$	17,402		19,077
	____________________
	-1	Gains or losses (realized/unrealized) are included in noninterest income in the consolidated statements of income.
Fair Value Measurements, Nonrecurring [Table Text Block]	Assets measured at fair value on a nonrecurring basis as of March 31, 2015 and December 31, 2014 are reflected in the following table:
		Fair Value Measurements
	(dollars in thousands)	Level 1			Level 2		Level 3	Fair Value
	March 31, 2015:
	Assets:
	Impaired loans:
	Commercial, financial and agricultural	$	—		—		7,033	7,033
	Real estate construction and development	—			—		3,396	3,396
	Real estate mortgage:
	Residential mortgage	—			—		81,475	81,475
	Home equity	—			—		5,070	5,070
	Multi-family residential	—			—		17,782	17,782
	Commercial real estate	—			—		3,788	3,788
	Consumer and installment	—			—		4	4
	Other real estate	—			—		15,227	15,227
	Total	$	—		—		133,775	133,775
	December 31, 2014:
	Assets:
	Impaired loans:
	Commercial, financial and agricultural	$	—		—		8,144	8,144
	Real estate construction and development	—			—		3,516	3,516
	Real estate mortgage:
	Residential mortgage	—			—		82,479	82,479
	Home equity	—			—		5,465	5,465
	Multi-family residential	—			—		18,574	18,574
	Commercial real estate	—			—		7,424	7,424
	Consumer and installment	—			—		22	22
	Other real estate	—			—		55,666	55,666
	Total	$	—		—		181,290	181,290
Fair Value, by Balance Sheet Grouping [Table Text Block]	The estimated fair value of the Company’s financial instruments at March 31, 2015 was as follows:
		March 31, 2015
		Carrying			Estimated Fair Value
	(dollars in thousands)	Value			Level 1		Level 2	Level 3		Total
	Financial Assets:
	Cash and cash equivalents	$	230,735		230,735		—	—		230,735
	Investment securities:
	Available for sale	1,554,442			1,985		1,552,457	—		1,554,442
	Held to maturity	595,335			—		597,341	—		597,341
	Loans held for portfolio	3,085,600			—		—	3,096,743		3,096,743
	Loans held for sale	43,655			—		43,655	—		43,655
	Derivative instruments	984			—		984	—		984
	Accrued interest receivable	15,867			15,867		—	—		15,867
	Financial Liabilities:
	Deposits	$	4,972,089		4,049,806		—	921,817		4,971,623
	Securities sold under agreements to repurchase	51,032			51,032		—	—		51,032
	Accrued interest payable	830			830		—	—		830
	Subordinated debentures	354,305			—		—	270,473		270,473
	Liability for Off-Balance Sheet Financial Instruments:
	Commitments to extend credit, standby letters of credit and financial guarantees	$	12		—		—	12		12
	The estimated fair value of the Company’s financial instruments at December 31, 2014 was as follows:
		December 31, 2014
		Carrying			Estimated Fair Value
	(dollars in thousands)	Value			Level 1		Level 2	Level 3		Total
	Financial Assets:
	Cash and cash equivalents	$	205,402		205,402		—	—		205,402
	Investment securities:
	Available for sale	1,445,689			1,967		1,443,722	—		1,445,689
	Held to maturity	618,148			—		614,272	—		614,272
	Loans held for portfolio	3,050,958			—		—	2,937,948		2,937,948
	Loans held for sale	31,411			—		31,411	—		31,411
	Derivative instruments	286			—		286	—		286
	Accrued interest receivable	15,064			15,064		—	—		15,064
	Financial Liabilities:
	Deposits	$	4,849,504		3,923,627		—	924,955		4,848,582
	Securities sold under agreements to repurchase	64,875			64,875		—	—		64,875
	Accrued interest payable	831			831		—	—		831
	Subordinated debentures	354,286			—		—	303,191		303,191
	Liability for Off-Balance Sheet Financial Instruments:
	Commitments to extend credit, standby letters of credit and financial guarantees	$	12		—		—	12		12

BUSINESS_SEGMENT_RESULTS_Table

BUSINESS SEGMENT RESULTS (Tables)	3 Months Ended
	Mar. 31, 2015
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment [Table Text Block]	The business segment results are consistent with the Company’s internal reporting system and, in all material respects, with GAAP and practices predominant in the banking industry. The business segment results are summarized as follows:
		First Bank				Corporate, Other and				Consolidated Totals
						Intercompany
						Reclassifications
	(dollars in thousands)	March 31,		December 31,		March 31,		December 31,		March 31,	December 31,
		2015		2014		2015		2014		2015	2014
	Balance sheet information:
	Investment securities	$	2,149,777	2,063,837		—		—		2,149,777	2,063,837
	Total loans	3,193,397		3,149,243		—		—		3,193,397	3,149,243
	FRB and FHLB stock	30,348		30,458		—		—		30,348	30,458
	Total assets	5,992,340		5,882,222		54,290		53,297		6,046,630	5,935,519
	Deposits	4,997,353		4,871,140		(25,264	)	(21,636	)	4,972,089	4,849,504
	Securities sold under agreements to repurchase	51,032		64,875		—		—		51,032	64,875
	Subordinated debentures	—		—		354,305		354,286		354,305	354,286
	Stockholders’ equity	872,736		871,301		(353,365	)	(358,857	)	519,371	512,444
		First Bank				Corporate, Other and				Consolidated Totals
						Intercompany
						Reclassifications
		Three Months Ended				Three Months Ended				Three Months Ended
		March 31,				March 31,				March 31,
	(dollars in thousands)	2015		2014		2015		2014		2015	2014
	Income statement information:
	Interest income	$	41,666	42,189		—		—		41,666	42,189
	Interest expense	2,075		2,051		3,004		3,798		5,079	5,849
	Net interest income (loss)	39,591		40,138		(3,004	)	(3,798	)	36,587	36,340
	Provision for loan losses	—		—		—		—		—	—
	Net interest income (loss) after provision for loan losses	39,591		40,138		(3,004	)	(3,798	)	36,587	36,340
	Noninterest income	18,037		14,169		91		116		18,128	14,285
	Noninterest expense	50,243		42,603		176		(245	)	50,419	42,358
	Income (loss) before provision (benefit) for income taxes	7,385		11,704		(3,089	)	(3,437	)	4,296	8,267
	Provision (benefit) for income taxes	2,694		4,120		(1,081	)	(1,203	)	1,613	2,917
	Net income (loss)	4,691		7,584		(2,008	)	(2,234	)	2,683	5,350
	Net income (loss) attributable to noncontrolling interest in subsidiary	9		(55	)	—		—		9	(55	)
	Net income (loss) attributable to First Banks, Inc.	$	4,682	7,639		(2,008	)	(2,234	)	2,674	5,405

BASIS_OF_PRESENTATION_Textual_

BASIS OF PRESENTATION (Textual) (Details)	Mar. 31, 2015
First Bank [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	53.23%
First Capital America, Inc. [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	46.77%

INVESTMENTS_IN_DEBT_AND_EQUITY2

INVESTMENTS IN DEBT AND EQUITY SECURITIES (Securities Available for Sale) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Maturities With In One Year, Amortized Cost	$39,151	$28,514
Available-for-sale Securities, Maturities After One Through Five Years, Amortized Cost	163,418	169,684
Available-for-sale Securities, Maturities After Five Through Ten Years, Amortized Cost	180,752	139,283
Available-for-sale Securities, Maturities After Ten Years, Amortized Cost	1,151,372	1,096,365
Carrying value: Total Amortized Cost	1,534,693	1,433,846
Available-for-sale Securities, Gross Unrealized Gains	23,866	19,168
Available-for-sale Securities, Gross Unrealized Losses	-4,117	-7,325
Available-for-sale Securities, Fair Value	1,554,442	1,445,689
Available-for-sale Securities Weighted Average Yield	2.23%	2.25%
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	39,606	28,901
Available-for-sale Securities, Debt Maturities, Year One Through Five, Fair Value	166,357	172,561
Available-for-sale Securities, Debt Maturities, Year Five Through Ten, Fair Value	184,307	140,717
Available-for-sale Securities, Debt Maturities, After Ten Years, Fair Value	1,164,172	1,103,510
Available-for-sale Securities Weighted Average Yield With In One Year	2.57%	2.64%
Available-for-sale Securities Weighted Average Yield After One Through Five Years	1.96%	1.97%
Available-for-sale Securities Weighted Average Yield After Five Through Ten Years	2.58%	2.58%
Available-for-sale Securities Weighted Average Yield After Ten Years	2.20%	2.23%
U.S. Government sponsored agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Maturities With In One Year, Amortized Cost	0	0
Available-for-sale Securities, Maturities After One Through Five Years, Amortized Cost	29,904	29,942
Available-for-sale Securities, Maturities After Five Through Ten Years, Amortized Cost	20,114	20,119
Available-for-sale Securities, Maturities After Ten Years, Amortized Cost	201,168	180,098
Carrying value: Total Amortized Cost	251,186	230,159
Available-for-sale Securities, Gross Unrealized Gains	2,093	2,129
Available-for-sale Securities, Gross Unrealized Losses	-727	-557
Available-for-sale Securities, Fair Value	252,552	231,731
Available-for-sale Securities Weighted Average Yield	1.45%	1.39%
Residential mortgage-backed [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Maturities With In One Year, Amortized Cost	0	269
Available-for-sale Securities, Maturities After One Through Five Years, Amortized Cost	65,101	65,433
Available-for-sale Securities, Maturities After Five Through Ten Years, Amortized Cost	79,250	48,174
Available-for-sale Securities, Maturities After Ten Years, Amortized Cost	895,399	885,896
Carrying value: Total Amortized Cost	1,039,750	999,772
Available-for-sale Securities, Gross Unrealized Gains	18,814	14,189
Available-for-sale Securities, Gross Unrealized Losses	-2,308	-6,117
Available-for-sale Securities, Fair Value	1,056,256	1,007,844
Available-for-sale Securities Weighted Average Yield	2.38%	2.39%
Commercial mortgage-backed [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Maturities With In One Year, Amortized Cost	0	0
Available-for-sale Securities, Maturities After One Through Five Years, Amortized Cost	775	779
Available-for-sale Securities, Maturities After Five Through Ten Years, Amortized Cost	0	0
Available-for-sale Securities, Maturities After Ten Years, Amortized Cost	0	0
Carrying value: Total Amortized Cost	775	779
Available-for-sale Securities, Gross Unrealized Gains	63	58
Available-for-sale Securities, Gross Unrealized Losses	0	0
Available-for-sale Securities, Fair Value	838	837
Available-for-sale Securities Weighted Average Yield	4.95%	4.95%
State and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Maturities With In One Year, Amortized Cost	511	863
Available-for-sale Securities, Maturities After One Through Five Years, Amortized Cost	569	571
Available-for-sale Securities, Maturities After Five Through Ten Years, Amortized Cost	0	0
Available-for-sale Securities, Maturities After Ten Years, Amortized Cost	28,356	28,371
Carrying value: Total Amortized Cost	29,436	29,805
Available-for-sale Securities, Gross Unrealized Gains	26	33
Available-for-sale Securities, Gross Unrealized Losses	-268	-223
Available-for-sale Securities, Fair Value	29,194	29,615
Available-for-sale Securities Weighted Average Yield	1.04%	1.05%
Corporate notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Maturities With In One Year, Amortized Cost	38,640	27,382
Available-for-sale Securities, Maturities After One Through Five Years, Amortized Cost	67,069	72,959
Available-for-sale Securities, Maturities After Five Through Ten Years, Amortized Cost	81,388	70,990
Available-for-sale Securities, Maturities After Ten Years, Amortized Cost	24,449	0
Carrying value: Total Amortized Cost	211,546	171,331
Available-for-sale Securities, Gross Unrealized Gains	2,870	2,759
Available-for-sale Securities, Gross Unrealized Losses	-799	-395
Available-for-sale Securities, Fair Value	213,617	173,695
Available-for-sale Securities Weighted Average Yield	2.55%	2.75%
Equity investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Maturities With In One Year, Amortized Cost	0	0
Available-for-sale Securities, Maturities After One Through Five Years, Amortized Cost	0	0
Available-for-sale Securities, Maturities After Five Through Ten Years, Amortized Cost	0	0
Available-for-sale Securities, Maturities After Ten Years, Amortized Cost	2,000	2,000
Carrying value: Total Amortized Cost	2,000	2,000
Available-for-sale Securities, Gross Unrealized Gains	0	0
Available-for-sale Securities, Gross Unrealized Losses	-15	-33
Available-for-sale Securities, Fair Value	1,985	1,967
Available-for-sale Securities Weighted Average Yield	2.14%	2.15%
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year One Through Five, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, Year Five Through Ten, Fair Value	0	0
Available-for-sale Securities, Debt Maturities, After Ten Years, Fair Value	1,985	1,967
Debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	39,606	28,901
Available-for-sale Securities, Debt Maturities, Year One Through Five, Fair Value	166,357	172,561
Available-for-sale Securities, Debt Maturities, Year Five Through Ten, Fair Value	184,307	140,717
Available-for-sale Securities, Debt Maturities, After Ten Years, Fair Value	$1,162,187	$1,101,543

INVESTMENTS_IN_DEBT_AND_EQUITY3

INVESTMENTS IN DEBT AND EQUITY SECURITIES - (Securities Held to Maturity) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Debt Maturities, Within One Year, Net Carrying Amount	$561	$561
Held-to-maturity Securities, Debt Maturities, After One Through Five Years, Net Carrying Amount	103,884	105,995
Held-to-maturity Securities, Debt Maturities, After Five Through Ten Years, Net Carrying Amount	60,590	61,726
Held-to-maturity Securities, Debt Maturities, After Ten Years, Net Carrying Amount	430,300	449,866
Held-to-maturity Securities, Amortized Cost	595,335	618,148
Held-to-maturity Securities, Gross Unrealized Gains	4,078	1,974
Held-to-maturity Securities, Gross Unrealized Losses	-2,072	-5,850
Held-to-maturity Securities, Fair Value	597,341	614,272
Held-to-maturity Securities Weighted Average Yield	1.88%	1.85%
Held-to-maturity Securities Weighted Average Yield With In One Year	3.07%	3.07%
Held-to-maturity Securities Weighted Average Yield After One Through Five Years	1.93%	1.88%
Held-to-maturity Securities Weighted Average Yield After Five Through Ten Years	1.25%	1.13%
Held-to-maturity Securities Weighted Average Yield After Ten Years	1.95%	1.94%
U.S. Government sponsored agencies [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Debt Maturities, Within One Year, Net Carrying Amount	0	0
Held-to-maturity Securities, Debt Maturities, After One Through Five Years, Net Carrying Amount	0	0
Held-to-maturity Securities, Debt Maturities, After Five Through Ten Years, Net Carrying Amount	10,001	10,725
Held-to-maturity Securities, Debt Maturities, After Ten Years, Net Carrying Amount	0	0
Held-to-maturity Securities, Amortized Cost	10,001	10,725
Held-to-maturity Securities, Gross Unrealized Gains	64	42
Held-to-maturity Securities, Gross Unrealized Losses	0	0
Held-to-maturity Securities, Fair Value	10,065	10,767
Held-to-maturity Securities Weighted Average Yield	1.29%	1.25%
Residential mortgage-backed [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Debt Maturities, Within One Year, Net Carrying Amount	0	0
Held-to-maturity Securities, Debt Maturities, After One Through Five Years, Net Carrying Amount	103,224	105,660
Held-to-maturity Securities, Debt Maturities, After Five Through Ten Years, Net Carrying Amount	48,400	50,512
Held-to-maturity Securities, Debt Maturities, After Ten Years, Net Carrying Amount	429,339	448,905
Held-to-maturity Securities, Amortized Cost	580,963	605,077
Held-to-maturity Securities, Gross Unrealized Gains	4,013	1,931
Held-to-maturity Securities, Gross Unrealized Losses	-1,984	-5,782
Held-to-maturity Securities, Fair Value	582,992	601,226
Held-to-maturity Securities Weighted Average Yield	1.89%	1.86%
State and political subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Debt Maturities, Within One Year, Net Carrying Amount	561	561
Held-to-maturity Securities, Debt Maturities, After One Through Five Years, Net Carrying Amount	660	335
Held-to-maturity Securities, Debt Maturities, After Five Through Ten Years, Net Carrying Amount	2,189	489
Held-to-maturity Securities, Debt Maturities, After Ten Years, Net Carrying Amount	961	961
Held-to-maturity Securities, Amortized Cost	4,371	2,346
Held-to-maturity Securities, Gross Unrealized Gains	1	1
Held-to-maturity Securities, Gross Unrealized Losses	-88	-68
Held-to-maturity Securities, Fair Value	4,284	2,279
Held-to-maturity Securities Weighted Average Yield	1.78%	1.68%
Debt securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Debt Maturities, Within One Year, Fair Value	561	561
Held-to-maturity Securities, Debt Maturities, After One Through Five Years, Fair Value	104,797	106,147
Held-to-maturity Securities, Debt Maturities, After Five Through Ten Years, Fair Value	61,100	62,000
Held-to-maturity Securities, Debt Maturities, After Ten Years, Fair Value	$430,883	$445,564

INVESTMENTS_IN_DEBT_AND_EQUITY4

INVESTMENTS IN DEBT AND EQUITY SECURITIES (Gross Realized Gains and Losses) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Gain (Loss) on Investments [Line Items]
Gross realized gains on sales of available-for-sale securities	$560	$2,010
Gross realized losses on sales of available-for-sale securities	-517	-730
Net realized gain on investment securities	$43	$1,280

INVESTMENTS_IN_DEBT_AND_EQUITY5

INVESTMENTS IN DEBT AND EQUITY SECURITIES (Schedule of Continuous Unrealized Losses) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Held to maturity:
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	$102,643	$29,012
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	-413	-115
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	120,804	326,716
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	-1,659	-5,735
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	223,447	355,728
Held-to-maturity Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	-2,072	-5,850
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	203,215	323,350
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	-1,883	-2,187
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	137,092	211,199
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	-2,234	-5,138
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	340,307	534,549
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	-4,117	-7,325
U.S. Government sponsored agencies [Member]
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	86,684	79,207
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	-592	-427
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	14,600	14,600
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	-135	-130
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	101,284	93,807
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	-727	-557
Residential mortgage-backed [Member]
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	66,185	204,378
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	-252	-1,154
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	117,535	191,644
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	-2,056	-4,963
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	183,720	396,022
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	-2,308	-6,117
State and political subdivisions [Member]
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	28,087	28,148
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	-268	-223
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	28,087	28,148
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	-268	-223
Corporate notes [Member]
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	20,274	9,650
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	-756	-350
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	4,957	4,955
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	-43	-45
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	25,231	14,605
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	-799	-395
Equity investments [Member]
Available for sale:
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	1,985	1,967
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	-15	-33
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	1,985	1,967
Available-for-sale Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	-15	-33
Residential mortgage-backed [Member]
Held to maturity:
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	100,000	28,371
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	-386	-112
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	119,905	325,820
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	-1,598	-5,670
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	219,905	354,191
Held-to-maturity Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	-1,984	-5,782
State and political subdivisions [Member]
Held to maturity:
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	2,643	641
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Gross Unrealized Losses	-27	-3
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	899	896
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Gross Unrealized Losses	-61	-65
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	3,542	1,537
Held-to-maturity Securities, Continuous Unrealized Loss Position, Gross Unrealized Losses	($88)	($68)

INVESTMENTS_IN_DEBT_AND_EQUITY6

INVESTMENTS IN DEBT AND EQUITY SECURITIES (Textual) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
	security		security
Proceeds from sales of investment securities available for sale	$44,768,000	$166,320,000
Securities pledged as collateral	$366,400,000		$349,000,000
Number of securities in unrealized loss positions greater than or equal to 12 months	27		47

LOANS_AND_ALLOWANCE_FOR_LOAN_L2

LOANS AND ALLOWANCE FOR LOAN LOSSES (Loan Portfolio Composition) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial, financial and agricultural	$700,183	$695,267
Real estate construction and development	110,705	89,851
Real estate mortgage:
Real estate mortgage	2,319,175	2,315,186
Consumer and installment	20,956	18,950
Net deferred loan fees	-1,277	-1,422
Total loans held for portfolio	3,149,742	3,117,832
Loans held for sale	43,655	31,411
Total loans	3,193,397	3,149,243
One-to-four-family residential [Member]
Real estate mortgage:
Real estate mortgage	1,030,088	1,016,710
Total loans held for portfolio	1,030,088	1,016,710
Multi-family residential [Member]
Real estate mortgage:
Real estate mortgage	114,288	115,434
Total loans held for portfolio	114,288	115,434
Total loans	114,288	115,434
Commercial real estate [Member]
Real estate mortgage:
Real estate mortgage	1,174,799	1,183,042
Total loans held for portfolio	1,174,799	1,183,042
Total loans	$1,174,799	$1,183,042

LOANS_AND_ALLOWANCE_FOR_LOAN_L3

LOANS AND ALLOWANCE FOR LOAN LOSSES (Aging of Loans by Loan Classification) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days	$5,965	$5,442
60-89 Days	1,705	1,837
Recorded Investment Greater Than 90 Days Accruing	15	163
Nonaccrual	50,840	57,476
Total Past Due	58,525	64,918
Current	3,134,872	3,084,325
Total loans	3,193,397	3,149,243
Commercial, financial and agricultural [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days	59	132
60-89 Days	227	430
Recorded Investment Greater Than 90 Days Accruing	0	54
Nonaccrual	7,240	9,486
Total Past Due	7,526	10,102
Current	692,657	685,165
Total loans	700,183	695,267
Real estate construction and development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days	781	431
60-89 Days	102	0
Recorded Investment Greater Than 90 Days Accruing	0	0
Nonaccrual	3,308	3,393
Total Past Due	4,191	3,824
Current	106,514	86,027
Total loans	110,705	89,851
Residential mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days	3,014	2,690
60-89 Days	952	986
Recorded Investment Greater Than 90 Days Accruing	15	35
Nonaccrual	10,911	13,890
Total Past Due	14,892	17,601
Current	613,181	603,567
Total loans	628,073	621,168
Home equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days	810	1,857
60-89 Days	374	334
Recorded Investment Greater Than 90 Days Accruing	0	72
Nonaccrual	6,337	6,831
Total Past Due	7,521	9,094
Current	394,494	386,448
Total loans	402,015	395,542
Multi-family residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days	0	0
60-89 Days	0	0
Recorded Investment Greater Than 90 Days Accruing	0	0
Nonaccrual	18,994	19,731
Total Past Due	18,994	19,731
Current	95,294	95,703
Total loans	114,288	115,434
Commercial real estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days	1,201	196
60-89 Days	32	54
Recorded Investment Greater Than 90 Days Accruing	0	0
Nonaccrual	4,046	4,122
Total Past Due	5,279	4,372
Current	1,169,520	1,178,670
Total loans	1,174,799	1,183,042
Consumer and installment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days	100	136
60-89 Days	18	33
Recorded Investment Greater Than 90 Days Accruing	0	2
Nonaccrual	4	23
Total Past Due	122	194
Current	19,557	17,334
Total loans	19,679	17,528
Loans held for sale [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
30-59 Days	0	0
60-89 Days	0	0
Recorded Investment Greater Than 90 Days Accruing	0	0
Nonaccrual	0	0
Total Past Due	0	0
Current	43,655	31,411
Total loans	$43,655	$31,411

LOANS_AND_ALLOWANCE_FOR_LOAN_L4

LOANS AND ALLOWANCE FOR LOAN LOSSES (Financing Receivable Credit Quality Indicators) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	$3,149,742	$3,117,832
Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	2,099,975	2,083,594
Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	1,049,767	1,034,238
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	700,183	695,267
Commercial and Industrial [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	700,183	695,267
Real Estate Construction and Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	110,705	89,851
Real Estate Construction and Development [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	110,705	89,851
Multi-family [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	114,288	115,434
Multi-family [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	114,288	115,434
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	1,174,799	1,183,042
Commercial Real Estate [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	1,174,799	1,183,042
Residential Mortgage [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	628,073	621,168
Home Equity [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	402,015	395,542
Consumer and Installment and Net Deferred Loan Fees [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	19,679	17,528
Consumer and Installment and Net Deferred Loan Fees [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	19,679	17,528
Pass [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	2,004,866	1,976,896
Pass [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	951,780	932,170
Pass [Member] | Commercial and Industrial [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	663,849	653,951
Pass [Member] | Real Estate Construction and Development [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	106,986	85,973
Pass [Member] | Multi-family [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	88,787	89,148
Pass [Member] | Commercial Real Estate [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	1,145,244	1,147,824
Pass [Member] | Residential Mortgage [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	537,729	528,388
Pass [Member] | Home Equity [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	394,494	386,448
Pass [Member] | Consumer and Installment and Net Deferred Loan Fees [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	19,557	17,334
Special mention [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	40,021	45,492
Special mention [Member] | Commercial and Industrial [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	16,359	18,713
Special mention [Member] | Real Estate Construction and Development [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	92	143
Special mention [Member] | Multi-family [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	5,870	5,945
Special mention [Member] | Commercial Real Estate [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	17,700	20,691
Substandard [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	20,909	20,083
Substandard [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	3,195	5,096
Substandard [Member] | Commercial and Industrial [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	12,463	12,833
Substandard [Member] | Real Estate Construction and Development [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	0	0
Substandard [Member] | Multi-family [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	637	610
Substandard [Member] | Commercial Real Estate [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	7,809	6,640
Substandard [Member] | Residential Mortgage [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	1,893	2,662
Substandard [Member] | Home Equity [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	1,184	2,263
Substandard [Member] | Consumer and Installment and Net Deferred Loan Fees [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	118	171
Performing troubled debt restructuring [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	591	4,391
Performing troubled debt restructuring [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	77,540	76,228
Performing troubled debt restructuring [Member] | Commercial and Industrial [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	272	284
Performing troubled debt restructuring [Member] | Real Estate Construction and Development [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	319	342
Performing troubled debt restructuring [Member] | Multi-family [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	0	0
Performing troubled debt restructuring [Member] | Commercial Real Estate [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	0	3,765
Performing troubled debt restructuring [Member] | Residential Mortgage [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	77,540	76,228
Performing troubled debt restructuring [Member] | Home Equity [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	0	0
Performing troubled debt restructuring [Member] | Consumer and Installment and Net Deferred Loan Fees [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	0	0
Nonaccrual [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	33,588	36,732
Nonaccrual [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	17,252	20,744
Nonaccrual [Member] | Commercial and Industrial [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	7,240	9,486
Nonaccrual [Member] | Real Estate Construction and Development [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	3,308	3,393
Nonaccrual [Member] | Multi-family [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	18,994	19,731
Nonaccrual [Member] | Commercial Real Estate [Member] | Commercial Loan Portfolio Credit Exposure by Internally Assigned Credit Grade [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	4,046	4,122
Nonaccrual [Member] | Residential Mortgage [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	10,911	13,890
Nonaccrual [Member] | Home Equity [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	6,337	6,831
Nonaccrual [Member] | Consumer and Installment and Net Deferred Loan Fees [Member] | Consumer Loan Portfolio Credit Exposure by Payment Activity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans	$4	$23

LOANS_AND_ALLOWANCE_FOR_LOAN_L5

LOANS AND ALLOWANCE FOR LOAN LOSSES (Impaired Financing Receivables) (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Loan and Lease Receivables, Impaired [Abstract]
With No Related Allowance Recorded: Recorded Investment	$23,802	$27,732
With No Related Allowance Recorded: Unpaid Principal Balance	40,366	44,193
With No Related Allowance Recorded: Related Allowance for Loan Losses	0	0
With No Related Allowance Recorded: Average Recorded Investment	24,580	36,681
With No Related Allowance Recorded: Interest Income Recognized	0	1,075
With A Related Allowance Recorded: Recorded Investment	105,169	110,363
With A Related Allowance Recorded: Unpaid Principal Balance	131,917	148,866
With A Related Allowance Recorded: Related Allowance for Loan Losses	10,423	12,471
With A Related Allowance Recorded: Average Recorded Investment	108,955	118,877
With A Related Allowance Recorded: Interest Income Recognized	533	2,126
Recorded Investment, Total	128,971	138,095
Unpaid Principal Balance, Total	172,283	193,059
Related Allowance for Loan Losses, Total	10,423	12,471
Average Recorded Investment, Total	133,535	155,558
Interest Income Recognized, Total	533	3,201
Commercial, financial and agricultural [Member]
Loan and Lease Receivables, Impaired [Abstract]
With No Related Allowance Recorded: Recorded Investment	2,505	1,937
With No Related Allowance Recorded: Unpaid Principal Balance	3,401	2,911
With No Related Allowance Recorded: Related Allowance for Loan Losses	0	0
With No Related Allowance Recorded: Average Recorded Investment	2,881	2,278
With No Related Allowance Recorded: Interest Income Recognized	0	0
With A Related Allowance Recorded: Recorded Investment	5,007	7,833
With A Related Allowance Recorded: Unpaid Principal Balance	7,754	22,089
With A Related Allowance Recorded: Related Allowance for Loan Losses	479	1,626
With A Related Allowance Recorded: Average Recorded Investment	5,760	9,212
With A Related Allowance Recorded: Interest Income Recognized	3	6
Recorded Investment, Total	7,512	9,770
Unpaid Principal Balance, Total	11,155	25,000
Related Allowance for Loan Losses, Total	479	1,626
Average Recorded Investment, Total	8,641	11,490
Interest Income Recognized, Total	3	6
Real estate construction and development [Member]
Loan and Lease Receivables, Impaired [Abstract]
With No Related Allowance Recorded: Recorded Investment	2,622	2,626
With No Related Allowance Recorded: Unpaid Principal Balance	12,318	12,333
With No Related Allowance Recorded: Related Allowance for Loan Losses	0	0
With No Related Allowance Recorded: Average Recorded Investment	2,661	3,106
With No Related Allowance Recorded: Interest Income Recognized	0	0
With A Related Allowance Recorded: Recorded Investment	1,005	1,109
With A Related Allowance Recorded: Unpaid Principal Balance	3,259	3,403
With A Related Allowance Recorded: Related Allowance for Loan Losses	231	219
With A Related Allowance Recorded: Average Recorded Investment	1,020	1,312
With A Related Allowance Recorded: Interest Income Recognized	4	17
Recorded Investment, Total	3,627	3,735
Unpaid Principal Balance, Total	15,577	15,736
Related Allowance for Loan Losses, Total	231	219
Average Recorded Investment, Total	3,681	4,418
Interest Income Recognized, Total	4	17
Residential mortgage [Member]
Loan and Lease Receivables, Impaired [Abstract]
With No Related Allowance Recorded: Recorded Investment	0	0
With No Related Allowance Recorded: Unpaid Principal Balance	0	0
With No Related Allowance Recorded: Related Allowance for Loan Losses	0	0
With No Related Allowance Recorded: Average Recorded Investment	0	0
With No Related Allowance Recorded: Interest Income Recognized	0	0
With A Related Allowance Recorded: Recorded Investment	88,451	90,118
With A Related Allowance Recorded: Unpaid Principal Balance	104,415	106,163
With A Related Allowance Recorded: Related Allowance for Loan Losses	6,976	7,639
With A Related Allowance Recorded: Average Recorded Investment	89,285	94,835
With A Related Allowance Recorded: Interest Income Recognized	521	2,082
Recorded Investment, Total	88,451	90,118
Unpaid Principal Balance, Total	104,415	106,163
Related Allowance for Loan Losses, Total	6,976	7,639
Average Recorded Investment, Total	89,285	94,835
Interest Income Recognized, Total	521	2,082
Home equity [Member]
Loan and Lease Receivables, Impaired [Abstract]
With No Related Allowance Recorded: Recorded Investment	0	0
With No Related Allowance Recorded: Unpaid Principal Balance	0	0
With No Related Allowance Recorded: Related Allowance for Loan Losses	0	0
With No Related Allowance Recorded: Average Recorded Investment	0	0
With No Related Allowance Recorded: Interest Income Recognized	0	0
With A Related Allowance Recorded: Recorded Investment	6,337	6,831
With A Related Allowance Recorded: Unpaid Principal Balance	7,487	7,988
With A Related Allowance Recorded: Related Allowance for Loan Losses	1,267	1,366
With A Related Allowance Recorded: Average Recorded Investment	6,584	7,056
With A Related Allowance Recorded: Interest Income Recognized	0	0
Recorded Investment, Total	6,337	6,831
Unpaid Principal Balance, Total	7,487	7,988
Related Allowance for Loan Losses, Total	1,267	1,366
Average Recorded Investment, Total	6,584	7,056
Interest Income Recognized, Total	0	0
Multi-family residential [Member]
Loan and Lease Receivables, Impaired [Abstract]
With No Related Allowance Recorded: Recorded Investment	18,675	19,050
With No Related Allowance Recorded: Unpaid Principal Balance	24,647	24,759
With No Related Allowance Recorded: Related Allowance for Loan Losses	0	0
With No Related Allowance Recorded: Average Recorded Investment	19,038	25,234
With No Related Allowance Recorded: Interest Income Recognized	0	959
With A Related Allowance Recorded: Recorded Investment	319	681
With A Related Allowance Recorded: Unpaid Principal Balance	3,185	3,581
With A Related Allowance Recorded: Related Allowance for Loan Losses	1,212	1,157
With A Related Allowance Recorded: Average Recorded Investment	325	902
With A Related Allowance Recorded: Interest Income Recognized	0	0
Recorded Investment, Total	18,994	19,731
Unpaid Principal Balance, Total	27,832	28,340
Related Allowance for Loan Losses, Total	1,212	1,157
Average Recorded Investment, Total	19,363	26,136
Interest Income Recognized, Total	0	959
Commercial real estate [Member]
Loan and Lease Receivables, Impaired [Abstract]
With No Related Allowance Recorded: Recorded Investment	0	4,119
With No Related Allowance Recorded: Unpaid Principal Balance	0	4,190
With No Related Allowance Recorded: Related Allowance for Loan Losses	0	0
With No Related Allowance Recorded: Average Recorded Investment	0	6,063
With No Related Allowance Recorded: Interest Income Recognized	0	116
With A Related Allowance Recorded: Recorded Investment	4,046	3,768
With A Related Allowance Recorded: Unpaid Principal Balance	5,813	5,619
With A Related Allowance Recorded: Related Allowance for Loan Losses	258	463
With A Related Allowance Recorded: Average Recorded Investment	5,967	5,546
With A Related Allowance Recorded: Interest Income Recognized	0	21
Recorded Investment, Total	4,046	7,887
Unpaid Principal Balance, Total	5,813	9,809
Related Allowance for Loan Losses, Total	258	463
Average Recorded Investment, Total	5,967	11,609
Interest Income Recognized, Total	0	137
Consumer and installment [Member]
Loan and Lease Receivables, Impaired [Abstract]
With No Related Allowance Recorded: Recorded Investment	0	0
With No Related Allowance Recorded: Unpaid Principal Balance	0	0
With No Related Allowance Recorded: Related Allowance for Loan Losses	0	0
With No Related Allowance Recorded: Average Recorded Investment	0	0
With No Related Allowance Recorded: Interest Income Recognized	0	0
With A Related Allowance Recorded: Recorded Investment	4	23
With A Related Allowance Recorded: Unpaid Principal Balance	4	23
With A Related Allowance Recorded: Related Allowance for Loan Losses	0	1
With A Related Allowance Recorded: Average Recorded Investment	14	14
With A Related Allowance Recorded: Interest Income Recognized	5	0
Recorded Investment, Total	4	23
Unpaid Principal Balance, Total	4	23
Related Allowance for Loan Losses, Total	0	1
Average Recorded Investment, Total	14	14
Interest Income Recognized, Total	$5	$0

LOANS_AND_ALLOWANCE_FOR_LOAN_L6

LOANS AND ALLOWANCE FOR LOAN LOSSES (Troubled Debt Restructurings on Performing Financing Receivables) (Details) (Performing Troubled Debt Restructurings [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Financing Receivable, Modifications [Line Items]
Total performing troubled debt restructuring	$78,131	$80,619
Commercial, financial and agricultural [Member]
Financing Receivable, Modifications [Line Items]
Total performing troubled debt restructuring	272	284
Real estate construction and development [Member]
Financing Receivable, Modifications [Line Items]
Total performing troubled debt restructuring	319	342
One-to-four-family residential [Member]
Financing Receivable, Modifications [Line Items]
Total performing troubled debt restructuring	77,540	76,228
Commercial real estate [Member]
Financing Receivable, Modifications [Line Items]
Total performing troubled debt restructuring	$0	$3,765

LOANS_AND_ALLOWANCE_FOR_LOAN_L7

LOANS AND ALLOWANCE FOR LOAN LOSSES (Troubled Debt Restructurings on Nonperforming Financing Receivables) (Details) (Nonperforming Troubled Debt Restructurings [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Financing Receivable, Modifications [Line Items]
Total nonperforming troubled debt restructurings	$25,244	$26,455
Commercial, financial and agricultural [Member]
Financing Receivable, Modifications [Line Items]
Total nonperforming troubled debt restructurings	35	243
Real estate construction and development [Member]
Financing Receivable, Modifications [Line Items]
Total nonperforming troubled debt restructurings	2,784	2,788
One-to-four-family residential [Member]
Financing Receivable, Modifications [Line Items]
Total nonperforming troubled debt restructurings	3,378	4,003
Multi-family residential [Member]
Financing Receivable, Modifications [Line Items]
Total nonperforming troubled debt restructurings	18,676	19,050
Commercial real estate [Member]
Financing Receivable, Modifications [Line Items]
Total nonperforming troubled debt restructurings	$371	$371

LOANS_AND_ALLOWANCE_FOR_LOAN_L8

LOANS AND ALLOWANCE FOR LOAN LOSSES (Modified Troubled Debt Restructurings) (Details) (One-to-four-family residential [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
	contracts	contracts
One-to-four-family residential [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	6	15
Pre-Modification Outstanding Recorded Investment	$1,723	$2,580
Post-Modification Outstanding Recorded Investment	$1,640	$2,157

LOANS_AND_ALLOWANCE_FOR_LOAN_L9

LOANS AND ALLOWANCE FOR LOAN LOSSES (Modified Troubled Debt Restructurings That Subsequently Defaulted) (Details) (One-to-four-family residential [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
	contracts	contracts
One-to-four-family residential [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	1
Recorded Investment, Subsequently Defaulted	$0	$438

Recovered_Sheet1

LOANS AND ALLOWANCE FOR LOAN LOSSES (Allowance for Credit Losses on Financing Receivables By Portfolio Segments) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Allowance for loan losses:
Balance, beginning of period	$66,874	$81,033
Charge-offs	-4,744	-3,447
Recoveries	2,012	2,245
Provision (benefit) for loan losses	0	0
Balance, end of period	64,142	79,831
Commercial and Industrial [Member]
Allowance for loan losses:
Balance, beginning of period	12,574	13,401
Charge-offs	-2,987	-1,622
Recoveries	1,244	752
Provision (benefit) for loan losses	1,501	1,340
Balance, end of period	12,332	13,871
Real Estate Construction and Development [Member]
Allowance for loan losses:
Balance, beginning of period	3,490	7,407
Charge-offs	-40	-30
Recoveries	164	600
Provision (benefit) for loan losses	-860	-891
Balance, end of period	2,754	7,086
One-to-Four-Family Residential [Member]
Allowance for loan losses:
Balance, beginning of period	24,055	32,619
Charge-offs	-1,163	-1,426
Recoveries	500	791
Provision (benefit) for loan losses	-906	-764
Balance, end of period	22,486	31,220
Multi-family residential [Member]
Allowance for loan losses:
Balance, beginning of period	5,630	5,249
Charge-offs	-189	-132
Recoveries	56	7
Provision (benefit) for loan losses	77	145
Balance, end of period	5,574	5,269
Commercial Real Estate [Member]
Allowance for loan losses:
Balance, beginning of period	20,983	22,052
Charge-offs	-343	-188
Recoveries	21	57
Provision (benefit) for loan losses	225	122
Balance, end of period	20,886	22,043
Consumer and installment [Member]
Allowance for loan losses:
Balance, beginning of period	142	305
Charge-offs	-22	-49
Recoveries	27	38
Provision (benefit) for loan losses	-37	48
Balance, end of period	$110	$342

Recovered_Sheet2

LOANS AND ALLOWANCE FOR LOAN LOSSES (Impairment Method by Loan Category) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Allowance for loan losses:
Ending balance: Impaired loans individually evaluated for impairment	$918,000	$2,237,000
Ending balance: Impaired loans collectively evaluated for impairment	9,505,000	10,234,000
Ending balance: All other loans collectively evaluated for impairment	53,719,000	54,403,000
Balance, end of period	64,142,000	66,874,000	79,831,000	81,033,000
Total loans:
Ending balance: Impaired loans individually evaluated for impairment	30,702,000	37,541,000
Ending balance: Impaired loans collectively evaluated for impairment	98,269,000	100,554,000
Ending balance: All other loans collectively evaluated for impairment	3,020,771,000	2,979,737,000
Total loans held for portfolio	3,149,742,000	3,117,832,000
Commercial and Industrial [Member]
Allowance for loan losses:
Ending balance: Impaired loans individually evaluated for impairment	0	1,053,000
Ending balance: Impaired loans collectively evaluated for impairment	479,000	573,000
Ending balance: All other loans collectively evaluated for impairment	11,853,000	10,948,000
Balance, end of period	12,332,000	12,574,000	13,871,000	13,401,000
Total loans:
Ending balance: Impaired loans individually evaluated for impairment	2,505,000	4,712,000
Ending balance: Impaired loans collectively evaluated for impairment	5,007,000	5,058,000
Ending balance: All other loans collectively evaluated for impairment	692,671,000	685,497,000
Total loans held for portfolio	700,183,000	695,267,000
Real Estate Construction and Development [Member]
Allowance for loan losses:
Ending balance: Impaired loans individually evaluated for impairment	0	0
Ending balance: Impaired loans collectively evaluated for impairment	231,000	219,000
Ending balance: All other loans collectively evaluated for impairment	2,523,000	3,271,000
Balance, end of period	2,754,000	3,490,000	7,086,000	7,407,000
Total loans:
Ending balance: Impaired loans individually evaluated for impairment	2,622,000	2,626,000
Ending balance: Impaired loans collectively evaluated for impairment	1,005,000	1,109,000
Ending balance: All other loans collectively evaluated for impairment	107,078,000	86,116,000
Total loans held for portfolio	110,705,000	89,851,000
One-to-Four-Family Residential [Member]
Allowance for loan losses:
Ending balance: Impaired loans individually evaluated for impairment	918,000	1,184,000
Ending balance: Impaired loans collectively evaluated for impairment	7,325,000	7,821,000
Ending balance: All other loans collectively evaluated for impairment	14,243,000	15,050,000
Balance, end of period	22,486,000	24,055,000	31,220,000	32,619,000
Total loans:
Ending balance: Impaired loans individually evaluated for impairment	6,899,000	7,388,000
Ending balance: Impaired loans collectively evaluated for impairment	87,889,000	89,561,000
Ending balance: All other loans collectively evaluated for impairment	935,300,000	919,761,000
Total loans held for portfolio	1,030,088,000	1,016,710,000
Multi-family residential [Member]
Allowance for loan losses:
Ending balance: Impaired loans individually evaluated for impairment	0	0
Ending balance: Impaired loans collectively evaluated for impairment	1,212,000	1,157,000
Ending balance: All other loans collectively evaluated for impairment	4,362,000	4,473,000
Balance, end of period	5,574,000	5,630,000	5,269,000	5,249,000
Total loans:
Ending balance: Impaired loans individually evaluated for impairment	18,676,000	19,050,000
Ending balance: Impaired loans collectively evaluated for impairment	318,000	681,000
Ending balance: All other loans collectively evaluated for impairment	95,294,000	95,703,000
Total loans held for portfolio	114,288,000	115,434,000
Commercial Real Estate [Member]
Allowance for loan losses:
Ending balance: Impaired loans individually evaluated for impairment	0	0
Ending balance: Impaired loans collectively evaluated for impairment	258,000	463,000
Ending balance: All other loans collectively evaluated for impairment	20,628,000	20,520,000
Balance, end of period	20,886,000	20,983,000	22,043,000	22,052,000
Total loans:
Ending balance: Impaired loans individually evaluated for impairment	0	3,765,000
Ending balance: Impaired loans collectively evaluated for impairment	4,046,000	4,122,000
Ending balance: All other loans collectively evaluated for impairment	1,170,753,000	1,175,155,000
Total loans held for portfolio	1,174,799,000	1,183,042,000
Consumer and Installment and Net Deferred Loan Fees [Member]
Allowance for loan losses:
Ending balance: Impaired loans individually evaluated for impairment	0	0
Ending balance: Impaired loans collectively evaluated for impairment	0	1,000
Ending balance: All other loans collectively evaluated for impairment	110,000	141,000
Balance, end of period	110,000	142,000	342,000	305,000
Total loans:
Ending balance: Impaired loans individually evaluated for impairment	0	0
Ending balance: Impaired loans collectively evaluated for impairment	4,000	23,000
Ending balance: All other loans collectively evaluated for impairment	19,675,000	17,505,000
Total loans held for portfolio	$19,679,000	$17,528,000

Recovered_Sheet3

LOANS AND ALLOWANCE FOR LOAN LOSSES (Textual) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Impaired financing receivable individually evaluated for impairment	$30,702,000	$37,541,000
Allowance allocated to troubled debt restructurings	10,423,000	12,471,000
Minimum [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Impaired financing receivable individually evaluated for impairment	500,000
Troubled Debt Restructurings [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance allocated to troubled debt restructurings	5,800,000	6,100,000
Impaired Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing receivable, allowance for credit losses, accumulated write-downs	43,300,000	55,000,000
Hamp Program [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Troubled debt restructurings under HAMP Program	$72,800,000	$72,700,000

SERVICING_RIGHTS_Schedule_of_S

SERVICING RIGHTS (Schedule of Servicing Assets at Fair Value) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Mortgage Banking [Member]
Servicing Asset at Fair Value [Roll Forward]
Balance, beginning of period	$14,012		$14,211
Originated servicing rights	822		455
Purchased mortgage servicing rights	39		0
Change in fair value resulting from changes in valuation inputs or assumptions used in valuation model	-831	[1]	151	[1]
Other changes in fair value	-561	[2]	-422	[2]
Balance, end of period	13,481		14,395
SBA [Member]
Servicing Asset at Fair Value [Roll Forward]
Balance, beginning of period	4,001		4,643
Originated servicing rights	0		0
Change in fair value resulting from changes in valuation inputs or assumptions used in valuation model	133	[1]	175	[1]
Other changes in fair value	-213	[2]	-136	[2]
Balance, end of period	$3,921		$4,682
[1]	The change in fair value resulting from changes in valuation inputs or assumptions used in valuation model primarily reflects the change in discount rates and prepayment speed assumptions, primarily due to changes in interest rates.
[2]	Other changes in fair value reflect changes due to the collection/realization of expected cash flows over time.

SERVICING_RIGHTS_Textual_Detai

SERVICING RIGHTS (Textual) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Millions, unless otherwise specified
Mortgage Banking [Member]
Servicing Assets at Fair Value [Line Items]
Servicing Portfolio	$1,380	$1,370
SBA [Member]
Servicing Assets at Fair Value [Line Items]
Servicing Portfolio	$105	$114.40

DERIVATIVE_INSTRUMENTS_Schedul

DERIVATIVE INSTRUMENTS (Schedule of Derivative Instruments) (Details) (Not Designated as Hedging Instrument [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	$115,210	$59,062
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	984	286
Interest rate lock commitments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	43,610	20,762
Interest rate lock commitments [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	1,268	580
Forward commitments to sell mortgage-backed securities [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	71,600	38,300
Forward commitments to sell mortgage-backed securities [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Assets	($284)	($294)

DERIVATIVE_INSTRUMENTS_Schedul1

DERIVATIVE INSTRUMENTS (Schedule of Derivatives Not Designated as Hedging Instruments, Location in Statements of Income) (Details) (Not Designated as Hedging Instrument [Member], Gain on loans sold and held for sale [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Interest rate lock commitments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) on derivatives recognized in operations	$688	$115
Forward commitments to sell mortgage-backed securities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) on derivatives recognized in operations	$10	($282)

SUBORDINATED_DEBENTURES_Textua

SUBORDINATED DEBENTURES (Textual) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2013
			installment
Debt Instrument [Line Items]
Number of trusts created for issuing trust preferred securities	13
Number of prior quarterly periods for deferral of cash interest payments on junior subordinated debentures before payment of all the cumulative deferred interest in March 2014			18
Junior Subordinated Debt [Member]
Debt Instrument [Line Items]
Distributions accrued on junior subordinated debentures	$3	$3.80

STOCKHOLDERS_EQUITY_Schedule_o

STOCKHOLDERS' EQUITY (Schedule of Accumulated Other Comprehensive Income) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning of period	$10,111	$7,502
Other comprehensive income before reclassifications	4,237	4,432
Amounts reclassified from accumulated other comprehensive income	7	-732
Net current period other comprehensive income	4,244	3,700
Balance, end of period	14,355	11,202
Investment Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning of period	14,051	10,151
Other comprehensive income before reclassifications	4,237	4,432
Amounts reclassified from accumulated other comprehensive income	-25	-753
Net current period other comprehensive income	4,212	3,679
Balance, end of period	18,263	13,830
Defined Benefit Pension Plan [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning of period	-3,940	-2,649
Other comprehensive income before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income	32	21
Net current period other comprehensive income	32	21
Balance, end of period	($3,908)	($2,628)

STOCKHOLDERS_EQUITY_Textual_De

STOCKHOLDERS' EQUITY (Textual) (Details) (USD $)	3 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2013	Dec. 31, 2014
Class of Stock [Line Items]
Number of classes of preferred stock outstanding	4
Preferred Class C D [Member]
Class of Stock [Line Items]
Dividends deferred and accrued on preferred stock	$77.80		$77.80
Dividends on preferred stock if the Company had continued to declare and accrue dividends	9.6	4.1	33.2
Dividends that would have been accrued and deferred as of the balance sheet date if the Company had continued to declare and accrue dividends	124.7		115.1
Preferred Class C D [Member] | Regularly Scheduled Dividend Payments [Member]
Class of Stock [Line Items]
Dividends deferred and accrued on preferred stock	68.4		68.4
Preferred Class C D [Member] | Cumulative Dividends On Unpaid Regular Dividends [Member]
Class of Stock [Line Items]
Dividends deferred and accrued on preferred stock	$9.40		$9.40

REGULATORY_CAPITAL_AND_OTHER_R2

REGULATORY CAPITAL AND OTHER REGULATORY MATTERS (Schedule of Regulatory Capital ) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
First Banks, Inc. (Consolidated) [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital, Amount	$582,115	$475,312
Total Capital to Risk-Weighted Assets, Ratio	14.88%	12.25%
Total Capital Required for Capital Adequacy, Ratio	8.00%	8.00%
Tier One Capital, Amount	283,962	284,396
Tier One Capital to Risk-Weighted Assets, Ratio	7.26%	7.33%
Tier One Capital Required for Capital Adequacy, Ratio	6.00%	4.00%
Common Equity Tier One Risk Based Capital, Amount	-44,624
Common Equity Tier One Capital To Risk-Weighted Assets, Ratio	-1.14%
Common Equity Tier One Capital Required For Capital Adequacy, Ratio	4.50%
Tier One Leverage Capital, Amount	283,962	284,396
Tier One Leverage Capital to Average Assets, Ratio	5.02%	5.01%
Tier One Leverage Capital Required for Capital Adequacy, Ratio	4.00%	4.00%
First Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital, Amount	660,631	691,350
Total Capital to Risk-Weighted Assets, Ratio	16.80%	17.81%
Total Capital Required for Capital Adequacy, Ratio	8.00%	8.00%
Total Capital Required to be Well Capitalized, Ratio	10.00%	10.00%
Tier One Capital, Amount	612,837	642,593
Tier One Capital to Risk-Weighted Assets, Ratio	15.59%	16.55%
Tier One Capital Required for Capital Adequacy, Ratio	6.00%	4.00%
Tier One Capital Required to be Well Capitalized, Ratio	8.00%	6.00%
Common Equity Tier One Risk Based Capital, Amount	612,837
Common Equity Tier One Capital To Risk-Weighted Assets, Ratio	15.59%
Common Equity Tier One Capital Required For Capital Adequacy, Ratio	4.50%
Common Equity Tier One Capital To Be Well Capitalized, Ratio	6.50%
Tier One Leverage Capital, Amount	$612,837	$642,593
Tier One Leverage Capital to Average Assets, Ratio	10.78%	11.35%
Tier One Leverage Capital Required for Capital Adequacy, Ratio	4.00%	4.00%
Tier One Leverage Capital Required to be Well Capitalized, Ratio	5.00%	5.00%

REGULATORY_CAPITAL_AND_OTHER_R3

REGULATORY CAPITAL AND OTHER REGULATORY MATTERS (Textual) (Details)	Mar. 31, 2015
Banking and Thrift [Abstract]
Net deferred tax assets attributable to net operating loss and tax credit carryforwards as a percentage of total net deferred tax assets	91.80%

FAIR_VALUE_DISCLOSURES_Schedul

FAIR VALUE DISCLOSURES (Schedule of Items Measured on a Recurring Basis) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	$1,554,442	$1,445,689
U.S. Government sponsored agencies [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	252,552	231,731
Residential mortgage-backed [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	1,056,256	1,007,844
Commercial mortgage-backed [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	838	837
State and political subdivisions [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	29,194	29,615
Corporate notes [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	213,617	173,695
Equity investments [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	1,985	1,967
Fair Value, Measurements, Recurring [Member]
Assets, Fair Value Disclosure [Abstract]
Mortgage loans held for sale	43,655	31,411
Servicing rights	17,402	18,013
Total assets, fair value disclosure (recurring)	1,616,483	1,495,399
Fair Value, Measurements, Recurring [Member] | Interest rate lock commitments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets	1,268	580
Fair Value, Measurements, Recurring [Member] | Forward commitments to sell mortgage-backed securities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets	-284	-294
Fair Value, Measurements, Recurring [Member] | U.S. Government sponsored agencies [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	252,552	231,731
Fair Value, Measurements, Recurring [Member] | Residential mortgage-backed [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	1,056,256	1,007,844
Fair Value, Measurements, Recurring [Member] | Commercial mortgage-backed [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	838	837
Fair Value, Measurements, Recurring [Member] | State and political subdivisions [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	29,194	29,615
Fair Value, Measurements, Recurring [Member] | Corporate notes [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	213,617	173,695
Fair Value, Measurements, Recurring [Member] | Equity investments [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	1,985	1,967
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Mortgage loans held for sale	0	0
Servicing rights	0	0
Total assets, fair value disclosure (recurring)	1,985	1,967
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Interest rate lock commitments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Forward commitments to sell mortgage-backed securities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Government sponsored agencies [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Residential mortgage-backed [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial mortgage-backed [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | State and political subdivisions [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Corporate notes [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Equity investments [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	1,985	1,967
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Mortgage loans held for sale	43,655	31,411
Servicing rights	0	0
Total assets, fair value disclosure (recurring)	1,597,096	1,475,419
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest rate lock commitments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets	1,268	580
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Forward commitments to sell mortgage-backed securities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets	-284	-294
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government sponsored agencies [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	252,552	231,731
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Residential mortgage-backed [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	1,056,256	1,007,844
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial mortgage-backed [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	838	837
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | State and political subdivisions [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	29,194	29,615
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate notes [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	213,617	173,695
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Equity investments [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Mortgage loans held for sale	0	0
Servicing rights	17,402	18,013
Total assets, fair value disclosure (recurring)	17,402	18,013
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Interest rate lock commitments [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Forward commitments to sell mortgage-backed securities [Member]
Assets, Fair Value Disclosure [Abstract]
Derivative Assets	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Government sponsored agencies [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Residential mortgage-backed [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial mortgage-backed [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | State and political subdivisions [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Corporate notes [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Equity investments [Member]
Assets, Fair Value Disclosure [Abstract]
Available-for-sale Securities, Fair Value	$0	$0

FAIR_VALUE_DISCLOSURES_Schedul1

FAIR VALUE DISCLOSURES (Schedule of Changes in Fair Value of Level 3 Assets) (Details) (Servicing Rights [Member], Fair Value, Inputs, Level 3 [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Servicing Rights [Member] | Fair Value, Inputs, Level 3 [Member]
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance, beginning of period	$18,013		$18,854
Total gains or losses (realized/unrealized):
Included in earnings	-1,472	[1]	-232	[1]
Included in other comprehensive income	0		0
Issuances	822		455
Purchases	39		0
Transfers in and/or out of level 3	0		0
Balance, end of period	$17,402		$19,077
[1]	Gains or losses (realized/unrealized) are included in noninterest income in the consolidated statements of income.

FAIR_VALUE_DISCLOSURES_Schedul2

FAIR VALUE DISCLOSURES (Schedule of Items Measured on a Nonrecurring Basis) (Details) (Fair Value, Measurements, Nonrecurring [Member], USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets, Fair Value Disclosure [Abstract]
Other real estate, fair value disclosure	$15,227	$55,666
Total assets, fair value disclosure (nonrecurring)	133,775	181,290
Commercial, financial and agricultural [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	7,033	8,144
Real estate construction and development [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	3,396	3,516
Residential mortgage [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	81,475	82,479
Home equity [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	5,070	5,465
Multi-family residential [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	17,782	18,574
Commercial real estate [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	3,788	7,424
Consumer and installment [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	4	22
Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure [Abstract]
Other real estate, fair value disclosure	0	0
Total assets, fair value disclosure (nonrecurring)	0	0
Fair Value, Inputs, Level 1 [Member] | Commercial, financial and agricultural [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | Real estate construction and development [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | Residential mortgage [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | Home equity [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | Multi-family residential [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | Commercial real estate [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 1 [Member] | Consumer and installment [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure [Abstract]
Other real estate, fair value disclosure	0	0
Total assets, fair value disclosure (nonrecurring)	0	0
Fair Value, Inputs, Level 2 [Member] | Commercial, financial and agricultural [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 2 [Member] | Real estate construction and development [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 2 [Member] | Residential mortgage [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 2 [Member] | Home equity [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 2 [Member] | Multi-family residential [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 2 [Member] | Commercial real estate [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 2 [Member] | Consumer and installment [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	0	0
Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure [Abstract]
Other real estate, fair value disclosure	15,227	55,666
Total assets, fair value disclosure (nonrecurring)	133,775	181,290
Fair Value, Inputs, Level 3 [Member] | Commercial, financial and agricultural [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	7,033	8,144
Fair Value, Inputs, Level 3 [Member] | Real estate construction and development [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	3,396	3,516
Fair Value, Inputs, Level 3 [Member] | Residential mortgage [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	81,475	82,479
Fair Value, Inputs, Level 3 [Member] | Home equity [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	5,070	5,465
Fair Value, Inputs, Level 3 [Member] | Multi-family residential [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	17,782	18,574
Fair Value, Inputs, Level 3 [Member] | Commercial real estate [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	3,788	7,424
Fair Value, Inputs, Level 3 [Member] | Consumer and installment [Member]
Assets, Fair Value Disclosure [Abstract]
Impaired loans, net, fair value disclosure	$4	$22

FAIR_VALUE_DISCLOSURES_Estimat

FAIR VALUE DISCLOSURES (Estimated Fair Value of Financial Instruments) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Investment securities:
Available for sale	$1,554,442	$1,445,689
Held-to-maturity Securities, Fair Value	597,341	614,272
Estimate of Fair Value, Fair Value Disclosure [Member]
Financial Assets:
Cash and cash equivalents	230,735	205,402
Investment securities:
Available for sale	1,554,442	1,445,689
Held-to-maturity Securities, Fair Value	597,341	614,272
Loans held for portfolio	3,096,743	2,937,948
Loans held for sale	43,655	31,411
Derivative instruments	984	286
Accrued interest receivable	15,867	15,064
Financial Liabilities:
Deposits	4,971,623	4,848,582
Securities sold under agreements to repurchase	51,032	64,875
Accrued interest payable	830	831
Subordinated debentures	270,473	303,191
Liability for Off-Balance Sheet Financial Instruments:
Commitments to extend credit, standby letters of credit and financial guarantees	12	12
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 1 [Member]
Financial Assets:
Cash and cash equivalents	230,735	205,402
Investment securities:
Available for sale	1,985	1,967
Held-to-maturity Securities, Fair Value	0	0
Loans held for portfolio	0	0
Loans held for sale	0	0
Derivative instruments	0	0
Accrued interest receivable	15,867	15,064
Financial Liabilities:
Deposits	4,049,806	3,923,627
Securities sold under agreements to repurchase	51,032	64,875
Accrued interest payable	830	831
Subordinated debentures	0	0
Liability for Off-Balance Sheet Financial Instruments:
Commitments to extend credit, standby letters of credit and financial guarantees	0	0
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 2 [Member]
Financial Assets:
Cash and cash equivalents	0	0
Investment securities:
Available for sale	1,552,457	1,443,722
Held-to-maturity Securities, Fair Value	597,341	614,272
Loans held for portfolio	0	0
Loans held for sale	43,655	31,411
Derivative instruments	984	286
Accrued interest receivable	0	0
Financial Liabilities:
Deposits	0	0
Securities sold under agreements to repurchase	0	0
Accrued interest payable	0	0
Subordinated debentures	0	0
Liability for Off-Balance Sheet Financial Instruments:
Commitments to extend credit, standby letters of credit and financial guarantees	0	0
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 3 [Member]
Financial Assets:
Cash and cash equivalents	0	0
Investment securities:
Available for sale	0	0
Held-to-maturity Securities, Fair Value	0	0
Loans held for portfolio	3,096,743	2,937,948
Loans held for sale	0	0
Derivative instruments	0	0
Accrued interest receivable	0	0
Financial Liabilities:
Deposits	921,817	924,955
Securities sold under agreements to repurchase	0	0
Accrued interest payable	0	0
Subordinated debentures	270,473	303,191
Liability for Off-Balance Sheet Financial Instruments:
Commitments to extend credit, standby letters of credit and financial guarantees	12	12
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Financial Assets:
Cash and cash equivalents	230,735	205,402
Investment securities:
Available for sale	1,554,442	1,445,689
Held-to-maturity Securities, Fair Value	595,335	618,148
Loans held for portfolio	3,085,600	3,050,958
Loans held for sale	43,655	31,411
Derivative instruments	984	286
Accrued interest receivable	15,867	15,064
Financial Liabilities:
Deposits	4,972,089	4,849,504
Securities sold under agreements to repurchase	51,032	64,875
Accrued interest payable	830	831
Subordinated debentures	354,305	354,286
Liability for Off-Balance Sheet Financial Instruments:
Commitments to extend credit, standby letters of credit and financial guarantees	$12	$12

FAIR_VALUE_DISCLOSURES_Textual

FAIR VALUE DISCLOSURES (Textual) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Fair Value Disclosures [Abstract]
Loans transferred to other real estate	$459	$1,031
Write-downs on other real estate	$109	$97

BUSINESS_SEGMENT_RESULTS_Sched

BUSINESS SEGMENT RESULTS (Schedule of Business Segment Results) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Balance Sheet Related Disclosures [Abstract]
Investment securities	$2,149,777		$2,063,837
Total loans	3,193,397		3,149,243
FRB and FHLB stock	30,348		30,458
Total assets	6,046,630		5,935,519
Deposits	4,972,089		4,849,504
Securities sold under agreements to repurchase	51,032		64,875
Subordinated debentures	354,305		354,286
Stockholders’ equity	519,371	497,306	512,444	488,256
Income Statement Related Disclosures [Abstract]
Interest income	41,666	42,189
Interest expense	5,079	5,849
Net interest income (loss)	36,587	36,340
Provision for loan losses	0	0
Net interest income (loss) after provision for loan losses	36,587	36,340
Noninterest income	18,128	14,285
Noninterest expense	50,419	42,358
Income (loss) before provision (benefit) for income taxes	4,296	8,267
Provision (benefit) for income taxes	1,613	2,917
Net income (loss)	2,683	5,350
Net income (loss) attributable to noncontrolling interest in subsidiary	9	-55
Net income (loss) attributable to First Banks, Inc.	2,674	5,405
First Bank [Member] | Operating Segments [Member]
Balance Sheet Related Disclosures [Abstract]
Investment securities	2,149,777		2,063,837
Total loans	3,193,397		3,149,243
FRB and FHLB stock	30,348		30,458
Total assets	5,992,340		5,882,222
Deposits	4,997,353		4,871,140
Securities sold under agreements to repurchase	51,032		64,875
Subordinated debentures	0		0
Stockholders’ equity	872,736		871,301
Income Statement Related Disclosures [Abstract]
Interest income	41,666	42,189
Interest expense	2,075	2,051
Net interest income (loss)	39,591	40,138
Provision for loan losses	0	0
Net interest income (loss) after provision for loan losses	39,591	40,138
Noninterest income	18,037	14,169
Noninterest expense	50,243	42,603
Income (loss) before provision (benefit) for income taxes	7,385	11,704
Provision (benefit) for income taxes	2,694	4,120
Net income (loss)	4,691	7,584
Net income (loss) attributable to noncontrolling interest in subsidiary	9	-55
Net income (loss) attributable to First Banks, Inc.	4,682	7,639
Corporate, Other and Intercompany Reclassifications [Member]
Balance Sheet Related Disclosures [Abstract]
Investment securities	0		0
Total loans	0		0
FRB and FHLB stock	0		0
Total assets	54,290		53,297
Deposits	-25,264		-21,636
Securities sold under agreements to repurchase	0		0
Subordinated debentures	354,305		354,286
Stockholders’ equity	-353,365		-358,857
Income Statement Related Disclosures [Abstract]
Interest income	0	0
Interest expense	3,004	3,798
Net interest income (loss)	-3,004	-3,798
Provision for loan losses	0	0
Net interest income (loss) after provision for loan losses	-3,004	-3,798
Noninterest income	91	116
Noninterest expense	176	-245
Income (loss) before provision (benefit) for income taxes	-3,089	-3,437
Provision (benefit) for income taxes	-1,081	-1,203
Net income (loss)	-2,008	-2,234
Net income (loss) attributable to noncontrolling interest in subsidiary	0	0
Net income (loss) attributable to First Banks, Inc.	($2,008)	($2,234)

TRANSACTIONS_WITH_RELATED_PART1

TRANSACTIONS WITH RELATED PARTIES (Textual) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
First Services L P [Member]
Related Party Transaction [Line Items]
Service Fees Paid to Affiliate	$5,000,000	$4,900,000
First Services L P [Member] | Affiliate Services Agreement [Member]
Related Party Transaction [Line Items]
Incurred fees and other revenue from affiliate	54,000	60,000
First Services L P [Member] | Premises [Member]
Related Party Transaction [Line Items]
Proceeds from Rents Received	435,000	435,000
First Brokerage America L L C [Member]
Related Party Transaction [Line Items]
Commissions Received From Unaffliated Third Party Companies	1,000,000	1,000,000
First Brokerage America L L C [Member] | Premises [Member]
Related Party Transaction [Line Items]
Proceeds from Rents Received	117,000	93,000
Dierbergs Markets Inc [Member]
Related Party Transaction [Line Items]
Operating Leases, Rent Expense, Net	128,000	126,000
First Bank [Member]
Related Party Transaction [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	53.23%
First Capital America, Inc. [Member]
Related Party Transaction [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	46.77%
Loans to Directors, Executive Officers and/or their Affliates [Member]
Related Party Transaction [Line Items]
Loans and Leases Receivable, Related Parties	$9,200,000		$28,800,000