Sterling Bancorp (STL) 10-Q 12 Feb 14 2014 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Dec. 31, 2013	Feb. 10, 2014
Document and Entity Information [Abstract]	'	'
Entity Registrant Name	'STERLING BANCORP	'
Entity Central Index Key	'0001070154	'
Current Fiscal Year End Date	'--09-30	'
Entity Filer Category	'Accelerated Filer	'
Document Type	'10-Q	'
Document Period End Date	31-Dec-13	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Amendment Flag	'false	'
Entity Common Stock, Shares Outstanding	'	83,493,422

Consolidated_Balance_Sheets_Un

Consolidated Balance Sheets (Unaudited) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
ASSETS	'	'
Cash and due from banks	$152,662	$113,090
Securities:	'	'
Available for sale	1,153,313	954,393
Held to maturity, at amortized cost (fair value of $479,977 and $250,896 at December 31, 2013 and September 30, 2013, respectively)	486,902	253,999
Total securities	1,640,215	1,208,392
Loans held for sale	24,483	1,011
Gross loans	4,127,141	2,412,898
Allowance for loan losses	-30,612	-28,877
Total loans, net	4,096,529	2,384,021
Federal Home Loan Bank (“FHLB”) and Federal Reserve Bank stock, at cost	43,326	24,312
Accrued interest receivable	16,056	11,698
Premises and equipment, net	49,925	36,520
Goodwill	387,517	163,117
Core deposit and other intangible assets	53,020	5,891
Bank owned life insurance	117,030	60,914
Other real estate owned	11,751	6,022
Other assets	74,923	34,184
Total assets	6,667,437	4,049,172
LIABILITIES	'	'
Deposits	4,920,564	2,962,294
FHLB and other borrowings	489,787	442,602
FHLB borrowings	81,841	20,351
Senior Notes	98,123	98,033
Subordinated debentures	26,519	0
Mortgage escrow funds	13,460	12,646
Other liabilities	112,034	30,380
Total liabilities	5,742,328	3,566,306
STOCKHOLDERS' EQUITY	'	'
Preferred stock (par value $0.01 per share; 10,000,000 shares authorized; none issued or outstanding)	0	0
Common stock (par value $0.01 per share; 190,000,000 shares authorized; 83,955,647 and 44,351,046 shares outstanding at December 31, 2013 and September 30, 2013, respectively)	912	522
Additional paid-in capital	856,946	403,816
Unallocated common stock held by employee stock ownership plan (“ESOP”)	-4,993	-5,493
Treasury stock, at cost (7,290,377 and 7,837,010 shares at December 31, 2013 and September 30, 2013, respectively)	-82,176	-88,538
Retained earnings	173,885	187,889
Accumulated other comprehensive loss, net of taxes	-19,465	-15,330
Total stockholders’ equity	925,109	482,866
Total liabilities and stockholders’ equity	$6,667,437	$4,049,172

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (Unaudited) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, except Share data, unless otherwise specified
Securities held-to-maturity at fair value	$479,977	$250,896
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	190,000,000	75,000,000
Common stock, shares outstanding	89,955,647	44,351,046
Treasury stock, shares	7,290,377	7,837,010

Consolidated_Statements_of_Inc

Consolidated Statements of Income (Unaudited) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Interest and dividend income:	'	'
Loans	$43,288	$27,071
Taxable securities	6,903	4,284
Non-taxable securities	2,161	1,457
Other earning assets	359	333
Total interest and dividend income	52,711	33,145
Interest expense:	'	'
Deposits	1,834	2,097
Borrowings	5,001	3,125
Total interest expense	6,835	5,222
Net interest income	45,876	27,923
Provision for loan losses	3,000	2,950
Net interest income after provision for loan losses	42,876	24,973
Accounts payable factoring commissions and other related fees	2,226	0
mortgage bank income	1,616	746
Non-interest income:	'	'
Deposit fees and service charges	3,942	2,778
Net (loss) gain on sale of securities	-645	1,416
Net impairment loss in earnings	645	'
Bank owned life insurance	740	509
Investment management fees	540	705
Other	729	1,505
Total non-interest income	9,148	7,659
Non-interest expense:	'	'
Compensation and employee benefits	23,554	12,299
Stock-based compensation	991	500
Merger-related expenses	9,068	'
Occupancy and office operations	6,333	3,810
Amortization of Intangible Assets	1,875	261
Other real estate owned expense	368	285
FDIC insurance and regulatory assessments	1,164	718
Charge for asset write downs, retention, and severance compensation	22,166	0
Other	7,455	4,673
Total non-interest expense	72,974	22,546
Income before income tax expense	-20,950	10,086
Income tax expense	-6,948	3,066
Net income	($14,002)	$7,020
Weighted average common shares:	'	'
Weighted average common shares basic (shares)	70,493,305	43,637,315
Weighted average common shares diluted (shares)	70,493,305	43,721,091
Per common share	'	'
Per common share basic (USD per share)	($0.20)	$0.16
Per common share diluted (USD per share)	($0.20)	$0.16

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Net income	($14,002)	$7,020
Other comprehensive (loss) income:	'	'
Unrealized holding losses on securities available for sale net of related income tax benefit of ($4,443) and ($1,154)	-6,013	-1,693
Less:	'	'
Reclassification adjustment for realized (losses) gains included in net income, net of related income tax (benefit) expense of ($214) and $575	431	-841
Reclassification adjustment for other than temporary impaired losses included in net income, net of related income tax benefit of $0 and $10	0	-15
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax	-5,582	-2,519
Acceleration of future amortization of accumulated other comprehensive loss on defined benefit pension plan and change in funded status of defined benefit plans, net of related income tax benefit of $889 and $195	1,447	285
Other comprehensive loss	-4,135	-2,234
Total comprehensive (loss) income	($18,137)	$4,786

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) (Unaudited) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Unrealized holding gains (losses) on securities available for sale, related tax expense (benefit)	$4,443	($1,154)
Reclassification adjustment for net unrealized gains included in net income, related tax expense	214	575
Reclassification adjustment for other than temporary impaired losses included in net income, related income tax expense	0	-10
Change in funded status of defined benefit plans, related tax expense	$889	($195)

Consolidated_Statement_of_Chan

Consolidated Statement of Changes In Stockholders' Equity (Unaudited) (USD $)	Total	Common stock	Additional paid-in capital	Unallocated ESOP shares	Treasury stock	Retained earnings	Accumulated other comprehensive income
In Thousands, except Share data, unless otherwise specified
Balance at Sep. 30, 2013	$482,866	$522	$403,816	($5,493)	($88,538)	$187,889	($15,330)
Balance, shares at Sep. 30, 2013	44,351,046	'	'	'	'	'	'
Increase (Decrease) in Stockholders' Equity	'	'	'	'	'	'	'
Net income	-14,002	'	'	'	'	-14,002	0
Other Comprehensive Income (Loss), Net of Tax	-4,135	'	'	'	'	'	-4,135
Stock Issued During Period, Shares, Acquisitions	39,057,968	'	'	'	'	'	'
Stock Issued During Period, Value, Acquisitions	390	'	'	'	'	'	'
Business Combination, Consideration Transferred	457,759	'	457,369	'	'	'	'
Adjustments to Additional Paid in Capital, Share-based Compensation, Stock Options, Requisite Service Period Recognition	31	'	31	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Period Increase (Decrease)	93,591	'	'	'	'	'	'
Stock option transactions, net	1,244	0	157	0	1,089	-2	0
ESOP shares allocated or committed to be released for allocation (37,449 shares)	726	0	226	500	0	0	0
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures	453,042	'	'	'	'	'	'
Stock Issued During Period, Value, Restricted Stock Award, Forfeitures	620	0	4,653	0	5,273	0	0
Balance at Dec. 31, 2013	$925,109	$912	$856,946	($4,993)	($82,176)	$173,885	($19,465)
Balance, shares at Dec. 31, 2013	83,955,647	'	'	'	'	'	'

Consolidated_Statement_of_Chan1

Consolidated Statement of Changes In Stockholders' Equity (Parenthetical) (Unaudited)	12 Months Ended
	Sep. 30, 2013
Statement of Stockholders' Equity [Abstract]	'
ESOP shares allocated or committed to be released for allocation, shares	37,449

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (Unaudited) (USD $)	3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:	'	'
Net income	$14,002,000	($7,020,000)
Adjustments to reconcile net income to net cash provided by operating activities	'	'
Provision for loan losses	3,000,000	2,950,000
Loss on real estate owned	332,000	155,000
Depreciation of premises and equipment	1,617,000	1,158,000
Amortization of intangibles	1,875,000	261,000
Net gain on loans held for sale	-1,616,000	-746,000
Other than temporary impairment loss recorded in earnings	-645,000	'
Net gain on sale of securities	645,000	-1,416,000
Net gain on sale of premises and equipment	-93,000	-5,000
Net amortization of premium on securities	511,000	765,000
(Amortization) accretion on borrowings	87,000	-69,000
Accretion of early extinguishment fees on borrowings	364,000	367,000
ESOP and RRP expense	772,000	340,000
Stock option compensation expense	219,000	160,000
Originations of loans held for sale	-113,572,000	-24,701,000
Proceeds from sales of loans held for sale	122,020,000	27,529,000
Increase in cash surrender value of bank owned life insurance	-742,000	-509,000
Other adjustments (principally net changes in other assets and other liabilities)	7,621,000	-29,569,000
Net cash (used in) provided by operating activities	9,038,000	-16,310,000
Cash flows from investing activities:	'	'
Purchases of available for sale securities	-67,044,000	-87,084,000
Purchases of held to maturity securities	-54,315,000	-21,926,000
Proceeds from maturities, calls and other principal payments on securities:	'	'
Available for sale	42,972,000	61,352,000
Held to maturity	5,258,000	24,157,000
Proceeds from Sale of Available-for-sale Securities	247,650,000	41,965,000
Net change in loans	-9,780,000	-78,156,000
Proceeds from sales of other real estate owned	627,000	711,000
Sale (purchase) of FHLB stock, net	2,417,000	3,000
Payments to Acquire Federal Reserve Bank Stock	-13,755,000	0
Purchases of premises and equipment	-8,572,000	-756,000
Net cash used in investing activities	423,256,000	-59,734,000
Cash flows from financing activities:	'	'
Net Change Interest and Noninterest-bearing Deposits, Domestic	-289,376,000	-183,991,000
Net (decrease) increase in time deposits	-49,544,000	-22,776,000
Net increase in short-term borrowings	-103,378,000	0
Proceeds from Issuance of Long-term Debt	49,944,000	-63,000
Net increase in mortgage escrow funds	814,000	7,658,000
Payments for Repurchase of Common Stock	0	21,000
Proceeds from Stock Options Exercised	1,448,000	142,000
Other stock-based compensation transactions	31,000	13,000
Cash dividends paid	-2,661,000	-2,659,000
Net cash used in financing activities	-392,722,000	-201,697,000
Net decrease in cash and cash equivalents	39,572,000	-277,741,000
Cash and cash equivalents at beginning of period	113,090,000	437,982,000
Cash and cash equivalents at end of period	152,662,000	160,241,000
Supplemental information:	'	'
Interest payments	6,061,000	5,359,000
Income tax payments	4,651,000	117,000
Real Estate Acquired in Settlement of Loans	873,000	1,381,000
Securities held to maturity transferred to available for sale	165,230,000	0
Securities available for sale transferred to held to maturity	221,904,000	0
Non-cash assets acquired:	'	'
Securities available for sale	233,244,000	0
Noncash Or Part Noncash Acquisition held to maturity securities Acquired	374,721,000	0
Noncash or part Noncash Acquisition Loan held for sale acquired	30,341,000	0
Total loans, net	1,698,108,000	0
Federal Reserve Bank stock	7,680,000	0
Accrued interest receivable	6,590,000	0
Goodwill	224,400,000	0
Core deposit intangible	20,089,000	0
Noncash or Part Noncash Acquisition, Trade Name Acquired	20,500,000	0
Noncash or Part Noncash Acquisition, BOLI Acquired	55,374,000	0
Premises and equipment, net	23,594,000	0
Noncash or Part Noncash Acquisition, Other Real Estate Owned	5,815,000	0
Other assets	22,266,000	0
Total non-cash assets acquired	2,722,722,000	0
Liabilities assumed:	'	'
Deposits	2,297,190,000	0
FHLB borrowings	100,619,000	0
Noncash or Part Noncash Acquisition, other borrowings	62,465,000	0
Noncash or Part Noncash Acquisition, Net Subordinated Debentures	26,527,000	0
Other liabilities	55,960,000	0
Total liabilities assumed	2,542,761,000	0
Net non-cash assets acquired	179,961,000	0
Cash Acquired from Acquisition	277,798,000	0
Cash and cash equivalents acquired	$457,759,000	$0

Basis_of_Presentation

Basis of Presentation	3 Months Ended
	Dec. 31, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Basis of Presentation	'
	Basis of Presentation
	Merger with Sterling Bancorp
	On October 31, 2013, Provident New York Bancorp completed its merger with Sterling Bancorp (“legacy Sterling”). In connection with the merger, Provident New York Bancorp completed the following corporate actions:
	•	Legacy Sterling merged with and into Provident New York Bancorp. Provident New York Bancorp was the accounting acquirer and the surviving entity;
	•	Provident New York Bancorp changed its legal entity name to Sterling Bancorp and became a bank holding company and a financial holding company as defined by the Bank Holding Company Act of 1956, as amended;
	•	Provident Bank converted to a national bank charter;
	•	Sterling National Bank merged into Provident Bank;
	•	Provident Bank changed its legal entity name to Sterling National Bank; and
	•	Provident Municipal Bank merged into Sterling National Bank.
	We refer to the transactions detailed above collectively as the “Merger”.
	The operating results of Sterling Bancorp include the operating results produced by the assets acquired and liabilities assumed in the Merger for the period November 1, 2013 through December 31, 2013.
	The consolidated financial statements include the accounts of Sterling Bancorp (“Sterling”, the “Company” or when necessary “legacy Provident”), PBNY Holdings, Inc. which has an investment in PB Madison Title Agency L.P., a company that provides title searches and title insurance for residential and commercial real estate, LandSave Development, LLC an inactive subsidiary, Provident Risk Management (a captive insurance company), Sterling National Bank (the “Bank”) and the Bank’s wholly owned subsidiaries. These subsidiaries included at December 31, 2013 (i) Provident REIT, Inc., WSB Funding, Inc. and Sterling Real Estate Holding Company, Inc. which are real estate investment trusts that hold a portion of the Company’s real estate loans, (ii) Provest Services Corp. I, which has invested in a low-income housing partnership, (iii) Provest Services Corp. II, which has engaged a third-party provider to sell mutual funds and annuities to the Bank’s customers and (iv) companies that hold other real estate owned by the Bank. Intercompany transactions and balances are eliminated in consolidation.
	The consolidated financial statements have been prepared by management and, in the opinion of management, include all adjustments, consisting of normal recurring accruals, necessary for a fair presentation of the Company’s financial position and results of its operations as of the dates and for the periods presented. Although certain information and footnote disclosures have been condensed or omitted pursuant to the rules and regulations of the United States Securities and Exchange Commission applicable to quarterly reports on Form 10-Q, the Company believes that the disclosures are adequate to make the information presented clear. The results of operations for the three months ended December 31, 2013 are not necessarily indicative of results to be expected for other interim periods or the entire fiscal year ending September 30, 2014. The unaudited consolidated financial statements presented herein should be read in conjunction with the annual audited financial statements included in the Company’s Form10-K for the fiscal year ended September 30, 2013.
	The consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). In preparing the consolidated financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets, liabilities, income and expense. Actual results could differ significantly from these estimates. A material estimate that is particularly susceptible to near-term change is the allowance for loan losses, which reflects the application of a critical accounting policy (see Note 4. Loans).

Acquisition_Acquisition

Acquisition Acquisition	3 Months Ended
	Dec. 31, 2012
Acquisition [Abstract]	'
Business Combination Disclosure [Text Block]	'
	Acquisition
	On October 31, 2013, the Company completed the Merger. Under the terms of the Merger agreement, legacy Sterling shareholders received 1.2625 shares of the Company’s common stock for each share of legacy Sterling common stock, which resulted in the issuance of 39,057,968 shares. Based on the closing stock price of $11.72 per share on October 31, 2013, the aggregate consideration paid to legacy Sterling shareholders was $457,759. Consistent with the Company’s strategy, the primary reason for the Merger was the expansion of the Company’s geographic footprint in the greater New York metropolitan region and beyond.
	The assets acquired and liabilities assumed have been accounted for under the acquisition method of accounting. The assets and liabilities, both tangible and intangible, were recorded at their fair values as of October 31, 2013 based on management’s best estimate using the information available as of the Merger date. The application of the acquisition method of accounting resulted in the recognition of goodwill of $224,400, a core deposit intangible of $20,089 and a trade name intangible of $20,500.  As of October 31, 2013, legacy Sterling had assets with a carrying value of approximately $2.8 billion, including loans with a carrying value of approximately $1.7 billion, and deposits with a carrying value of approximately $2.3 billion. The table below summarizes the amounts recognized as of the Merger date for each major class of assets acquired and liabilities assumed, the estimated fair value adjustments and the amounts recorded in the Company’s financial statements at fair value at the Merger date:
	Consideration paid through Sterling Bancorp common stock issued to legacy Sterling shareholders				$	457,759
		Legacy Sterling carrying value				Fair value adjustments				As recorded at acquisition
	Cash and cash equivalents	$	277,798			$	—			$	277,798
	Investment securities	613,154				(5,189		)	(a)	607,965
	Loans held for sale	30,341				—				30,341
	Loans	1,704,801				(6,693		)	(b)	1,698,108
	Federal Reserve Bank stock	7,680				—				7,680
	Bank owned life insurance	55,374				—				55,374
	Premises and equipment	21,293				2,301			(c)	23,594
	Accrued interest receivable	6,590				—				6,590
	Core deposit and other intangibles	—				20,089			(d)	20,089
	Trade name intangible	—				20,500			(e)	20,500
	Other real estate owned	1,720				4,095			(f)	5,815
	Other assets	40,877				(18,611		)	(g)	22,266
	Deposits	(2,296,713		)		(477		)	(h)	(2,297,190		)
	FHLB borrowings	(100,346		)		(273		)	(i)	(100,619		)
	Other borrowings	(62,465		)		—				(62,465		)
	Subordinated debentures	(25,774		)		(753		)	(j)	(26,527		)
	Other liabilities	(60,462		)		4,502			(k)	(55,960		)
	Total identifiable net assets	$	213,868			$	19,491			$	233,359
	Goodwill recorded in the Merger									$	224,400
	Explanation of certain fair value related adjustments:
	(a)	Represents the fair value adjustment on investment securities held to maturity.
	(b)	Represents the elimination of legacy Sterling’s allowance for loan losses and an adjustment of the amortized cost of loans to estimated fair value, which includes an interest rate mark and credit mark.
	(c)	Represents an adjustment to reflect the fair value of leasehold improvements.
	(d)	Represents intangible assets recorded to reflect the fair value of core deposits and below market rent on leased premises. The core deposit asset was recorded as an identifiable intangible asset and will be amortized on an accelerated basis over the estimated average life of the deposit base. The below market rent intangible asset will be amortized on a straight-line basis over the remaining term of the leases.
	(e)	Represents the estimated fair value of Sterling Bancorp’s trade name. This intangible asset will not be amortized and will be reviewed at least annually for impairment.
	(f)	Represents an adjustment to an acquired property which legacy Sterling utilized as a financial center and recorded as premises and equipment. As the Company intends to sell this asset, it was recorded in other real estate owned at estimated fair value determined using an independent appraisal.
	(g)	Consists primarily of adjustments in net deferred tax assets resulting from the fair value adjustments related to the acquired assets, liabilities assumed and identifiable intangibles recorded.
	(h)	Represents the fair value adjustment on deposits as the weighted average interest rate of deposits assumed exceeded the cost of similar funding available in the market at the time of the Merger.
	(i)	Represents the fair value adjustment on FHLB borrowings as the weighted average interest rate of FHLB borrowings assumed exceeded the cost of similar funding available in the market at the time of the Merger.
	(j)	Represents the fair value adjustment on subordinated debentures as the weighted average interest rate of the debentures assumed exceeded the cost of similar debt funding available in the market at the time of the Merger.
	(k)	Represents the fair value of other liabilities assumed at the Merger date.
	Except for collateral dependent loans with deteriorated credit quality, the fair values for loans acquired from legacy Sterling were estimated using cash flow projections based on the remaining maturity and repricing terms. Cash flows were adjusted by estimating future credit losses and the rate of prepayments. Projected monthly cash flows were then discounted to present value using a risk-adjusted market rate for similar loans. For collateral dependent loans with deteriorated credit quality, fair value was estimated by analyzing the value of the underlying collateral, assuming the fair values of the loans were derived from the eventual sale of the collateral. These values were discounted using market derived rates of return, with consideration given to the period of time and costs associated with the foreclosure and disposition of the collateral. There was no carryover of legacy Sterling’s allowance for loan losses associated with the loans that were acquired, as the loans were initially recorded at fair value on the date of the Merger.
	The acquired loan portfolio subject to purchased credit impairment accounting guidance (ASC 310-30) as of October 31, 2013 was comprised of collateral dependent loans with deteriorated credit quality as follows:
		ASC 310-30 loans
	Contractual principal balance at acquisition	$	24,176
	Principal not expected to be collected (non-accretable discount)	(10,927		)
	Expected cash flows at acquisition	13,249
	Interest component of expected cash flows (accretable discount)	—
	Fair value of acquired loans	$	13,249
	The core deposit intangible asset recognized is being amortized over its estimated useful life of approximately 10 years utilizing the accelerated method. Other intangibles consist of below market rents which are amortized over the remaining life of each lease using the straight-line method.
	Goodwill is not amortized for book purposes; however, it is reviewed at least annually for impairment and is not deductible for tax purposes.
	The fair value of premises and equipment and other real estate owned was estimated using appraisals of like kind properties and assets. Premises, equipment and leasehold improvements will be amortized or depreciated over their estimated useful lives ranging from one to five years for equipment or over the life of the lease for leasehold improvements. Other real estate owned is not amortized and is carried at estimated fair value determined by the appraised value less costs to sell.
	The fair value of retail demand and interest bearing deposit accounts was assumed to approximate the carrying value as these accounts have no stated maturity and are payable on demand. The fair value of time deposits was estimated by discounting the contractual future cash flows using market rates offered for time deposits of similar remaining maturities. The fair value of borrowed funds was estimated by discounting the future cash flows using market rates for similar borrowings.
	Direct acquisition and integration costs of the Merger were expensed as incurred and totaled $9.1 million and $0 for the three months ended December 31, 2013 and 2012, respectively. These items were recorded as Merger-related expenses on the statement of operations. Other integration costs of the Merger for the three months ended December 31, 2013 included a charge for assets write-downs, employee retention and severance compensation which totaled $22.2 million. These items were recorded in non-interest expense in the statement of operations.
	The following table presents selected unaudited pro forma financial information reflecting the Merger assuming it was completed as of October 1, 2012. The unaudited pro forma financial information is presented for illustrative purposes only and is not necessarily indicative of the financial results of the combined companies had the Merger actually been completed at the beginning of the periods presented, nor does it indicate future results for any other interim or full fiscal year period. Pro forma basic and diluted earnings per common share were calculated using the Company’s actual weighted average shares outstanding for the periods presented, plus the incremental shares issued, assuming the legacy Sterling Merger occurred at the beginning of the periods presented. The unaudited pro forma information is based on the actual financial statements of the Company for the periods presented, and on the actual financial statements of legacy Sterling for the 2012 period presented and in 2013 until the date of the Merger, at which time legacy Sterling’s results of operations were included in the Company’s financial statements.
	The unaudited pro forma information, for the three months ended December 31, 2013 and 2012, set forth below reflects adjustments related to (a) purchase accounting fair value adjustments; (b) amortization of core deposit and other intangibles; and (c) adjustments to interest income and expense due to amortization of premiums and accretion of discounts. Direct Merger-related expenses and charges incurred in the fiscal quarter ended December 31, 2013 to write-down assets and accrue for retention and severance compensation are assumed to have occurred prior to October 1, 2012. Furthermore, the unaudited pro forma information does not reflect management’s estimate of any revenue enhancement opportunities or anticipated potential cost savings.
		Pro forma for the
		three months ended December 31,
		2013				2012
	Net interest income	$	53,188			$	55,011
	Non-interest income	16,174				16,796
	Non-interest expense	50,378				49,391
	Net income	11,480				11,028
	Pro forma earnings per share from continuing operations:
	Basic	$	0.14			$	0.13
	Diluted	0.14				0.13

Securities

Securities	3 Months Ended
	Dec. 31, 2013
Marketable Securities [Abstract]	'
Securities	'
	Securities
	A summary of the amortized cost and estimated fair value of our securities is presented below:
		31-Dec-13												30-Sep-13
		Amortized			Gross			Gross			Fair value			Amortized		Gross			Gross			Fair value
		cost			unrealized			unrealized						cost		unrealized			unrealized
					gains			losses								gains			losses
	Available for Sale
	Residential mortgage-backed securities:
	Fannie Mae	$	236,701		$	557		$	(2,824	)	$	234,434		$	214,191	$	1,168		$	(3,921	)	$	211,438
	Freddie Mac	109,247			348			(859		)	108,736			67,272		593			(236		)	67,629
	Ginnie Mae	14,752			141			(67		)	14,826			3,374		88			—			3,462
	CMO/Other MBS	141,677			189			(2,601		)	139,265			169,336		356			(3,038		)	166,654
	Total residential mortgage-backed securities	502,377			1,235			(6,351		)	497,261			454,173		2,205			(7,195		)	449,183
	Other securities:
	Mutual funds	4,877			—			(23		)	4,854			—		—			—			—
	Federal agencies	264,082			32			(11,505		)	252,609			273,637		—			(12,090		)	261,547
	Corporate	202,225			84			(4,546		)	197,763			118,575		153			(3,795		)	114,933
	State and municipal	131,782			2,859			(1,547		)	133,094			127,324		3,447			(2,041		)	128,730
	Trust preferred	67,711			180			(159		)	67,732			—		—			—			—
	Total other securities	670,677			3,155			(17,780		)	656,052			519,536		3,600			(17,926		)	505,210
	Total available for sale	$	1,173,054		$	4,390		$	(24,131	)	$	1,153,313		$	973,709	$	5,805		$	(25,121	)	$	954,393
		31-Dec-13												30-Sep-13
		Amortized			Gross			Gross			Fair value			Amortized		Gross			Gross			Fair value
		cost			unrecognized			unrecognized						cost		unrecognized			unrecognized
					gains			losses								gains			losses
	Held to Maturity
	Residential mortgage-backed securities:
	Fannie Mae	$	65,336		$	71		$	(692	)	$	64,715		$	70,502	$	399		$	(86	)	$	70,815
	Freddie Mac	27,040			47			—			27,087			59,869		317			(22		)	60,164
	CMO/Other MBS	71,329			11			(993		)	70,347			25,776		33			(315		)	25,494
	Total residential mortgage-backed securities	163,705			129			(1,685		)	162,149			156,147		749			(423		)	156,473
	Other securities:
	Federal agencies	133,994			—			(3,623		)	130,371			77,341		—			(3,458		)	73,883
	State and municipal	187,703			615			(2,375		)	185,943			19,011		556			(546		)	19,021
	Other	1,500			14			—			1,514			1,500		19			—			1,519
	Total other securities	323,197			629			(5,998		)	317,828			97,852		575			(4,004		)	94,423
	Total held to maturity	$	486,902		$	758		$	(7,683	)	$	479,977		$	253,999	$	1,324		$	(4,427	)	$	250,896
	In accordance with ASC Subtopic 320-10-25-6, in a significant business combination a company may transfer held to maturity securities to available for sale securities to maintain the company’s existing interest rate risk position or credit risk policy. Based on management’s review of the combined investment securities portfolio and implications for asset and liability management, investment securities totaling $165,230 were transferred from held to maturity to available for sale. Investment securities that were transferred included residential mortgage-backed securities, federal agency securities and state and municipal securities and was based mainly on the premium amortization and extension risk inherent in these securities. Concurrent with this repositioning, a total of $221,904 of investment securities were also transferred from available for sale to held to maturity, as management intends to maintain a target of approximately 25% of total investment securities classified as held to maturity. Substantially all of the securities transferred from available for sale to held to maturity have a maturity date in 2020 or beyond. At the date of transfer, these securities were in an unrealized loss position of $9,657, which will be accreted into interest income using the level yield method over the life of the securities, which is estimated to be approximately 6 years. The unrealized loss amount is included in accumulated other comprehensive (loss) on an after-tax basis. Management believes the transfers of investment securities highlighted above maintain the Company’s interest rate risk position and credit risk profile on a combined basis post Merger.
	The amortized cost and estimated fair values of securities at December 31, 2013 are presented below by contractual maturity. Actual maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations. Residential mortgage-backed securities are shown separately since they are not due at a single maturity date.
		December 31, 2013
		Available for sale						Held to maturity
		Amortized			Fair			Amortized			Fair
		cost			value			cost			value
	Remaining period to contractual maturity:
	One year or less	$	41,392		$	41,352		$	5,408		$	5,463
	One to five years	117,527			117,328			5,209			5,471
	Five to ten years	387,364			373,665			144,734			141,202
	Greater than ten years	124,394			123,707			167,846			165,692
	Total other securities	670,677			656,052			323,197			317,828
	Residential mortgage-backed securities	502,377			497,261			163,705			162,149
	Total securities	$	1,173,054		$	1,153,313		$	486,902		$	479,977
	Sales of securities for the three months ended December 31, 2013 and 2012 were as follows:
		For the three months ended December 31,
		2013			2012
	Available for sale securities:
	Proceeds from sales	$	247,650		$	41,965
	Gross realized gains	211			1,416
	Gross realized losses	(856		)	—
	Income tax benefit (expense) on realized gains	214			(575		)
	The following table summarizes securities with unrealized losses, segregated by the length of time in a continuous unrealized loss position:
		Continuous unrealized loss position
		Less than 12 Months						12 months or longer						Total
		Fair			Unrealized			Fair			Unrealized			Fair		Unrealized
value			losses			value			losses			value		losses
Available for Sale
31-Dec-13
Residential mortgage-backed securities:
Agency-backed	$	227,935		$	(3,750	)	$	—		$	—		$	227,935	$	(3,750	)
CMO/Other MBS	114,362			(2,601		)	—			—			114,362		(2,601		)
Total residential mortgage-backed securities	342,297			(6,351		)	—			—			342,297		(6,351		)
Mutual fund	4,877			(23		)	—			—			4,877		(23		)
Federal agencies	239,612			(11,351		)	4,846			(154		)	244,458		(11,505		)
Corporate	171,851			(4,546		)	—			—			171,851		(4,546		)
State and municipal	56,139			(1,511		)	936			(36		)	57,075		(1,547		)
Trust preferred	47,634			(159		)	—			—			47,634		(159		)
Total	$	862,410		$	(23,941	)	$	5,782		$	(190	)	$	868,192	$	(24,131	)
30-Sep-13
Residential mortgage-backed securities:
Agency-backed	$	137,265		$	(4,157	)	$	—		$	—		$	137,265	$	(4,157	)
CMO/Other MBS	122,324			(2,742		)	7,820			(296		)	130,144		(3,038		)
Total residential mortgage-backed securities	259,589			(6,899		)	7,820			(296		)	267,409		(7,195		)
Federal agencies	261,547			(12,090		)	—			—			261,547		(12,090		)
Corporate	95,013			(3,795		)	—			—			95,013		(3,795		)
State and municipal	43,585			(2,033		)	112			(8		)	43,697		(2,041		)
Total	$	659,734		$	(24,817	)	$	7,932		$	(304	)	$	667,666	$	(25,121	)
	Continuous unrealized loss position
	Less than 12 Months						12 Months or longer						Total
	Fair			Unrealized			Fair			Unrealized			Fair		Unrealized
	value			losses			value			losses			value		losses
Held to Maturity
December 31, 2013
Residential mortgage-backed securities:
Agency-backed	$	50,558		$	(692	)	$	—		$	—		$	50,558	$	(692	)
CMO/Other MBS	65,219			(993		)	—			—			65,219		(993		)
Total residential mortgage-backed securities	115,777			(1,685		)	—			—			115,777		(1,685		)
Federal agencies	132,089			(3,623		)	—			—			132,089		(3,623		)
State and municipal	165,114			(2,375		)	—			—			165,114		(2,375		)
Total	$	412,980		$	(7,683	)	$	—		$	—		$	412,980	$	(7,683	)
30-Sep-13
Residential mortgage-backed securities:
Agency-backed	$	10,963		$	(86	)	$	—		$	—		$	10,963	$	(86	)
CMO/Other MBS	31,412			(337		)	—			—			31,412		(337		)
Total residential mortgage-backed securities	42,375			(423		)	—			—			42,375		(423		)
Federal agencies	73,883			(3,458		)	—			—			73,883		(3,458		)
State and municipal	9,530			(546		)	—			—			9,530		(546		)
Total	$	125,788		$	(4,427	)	$	—		$	—		$	125,788	$	(4,427	)
Substantially all of the unrealized losses at December 31, 2013 relate to investment grade debt securities and are attributable to changes in market interest rates subsequent to purchase. At December 31, 2013, a total of 323 available for sale securities were in a continuous unrealized loss position for less than 12 months and two securities were in an unrealized loss position for 12 months or longer. For securities with fixed maturities, there are no securities past due or securities for which the Company currently believes it is not probable that it will collect all amounts due according to the contractual terms of the investment.
Declines in the fair value of available for sale and held to maturity securities below their cost that are deemed to be other than temporary are reflected in earnings as realized losses to the extent the impairment is related to credit losses. The amount of the impairment related to other factors is recognized in other comprehensive income. In estimating other-than-temporary impairment losses (“OTTI”), management considers, among other things, (i) the length of time and the extent to which the fair value has been less than cost, (ii) the financial condition and near-term prospects of the issuer, and (iii) the intent and ability of the Company to retain the investment for a period of time sufficient to allow for an anticipated recovery in cost.
Within the CMO category of the available for sale portfolio there are four private label CMOs that had an amortized cost of $3,362 and a fair value (carrying value) of $3,356 as of December 31, 2013. OTTI was recognized on two of the four securities in prior periods and these securities are currently rated below investment grade. These private label CMOs had an amortized cost of $3,075 and an estimated fair value of $3,073 at December 31, 2013. Impairment charges on these securities were $0 and $14 for the three months ended December 31, 2013 and December 31, 2012, respectively. At December 31, 2013 total cumulative impairment charges on the two private label CMOs were $136. The remaining two securities were performing as of December 31, 2013 and are expected to continue to perform based on current information. In determining whether OTTI existed on the debt securities, the Company evaluated the present value of cash flows expected to be collected based on collateral specific assumptions, including credit risk and liquidity risk, and determined that no additional credit losses were expected. The Company will continue to evaluate its investment securities portfolio for OTTI on at least a quarterly basis.
Excluding FHLB stock, Federal Reserve Bank stock and New York Business Development Corporation stock, the Company owned one equity security with a balance of $826 at December 31, 2012, which was sold during the fiscal year ended September 30, 2013.
Securities pledged for borrowings at FHLB and other institutions, and securities pledged for municipal deposits and other purposes were as follows:
	December 31, 2013			September 30, 2013
Available for sale securities pledged for borrowings, at fair value	$	810,290		$	199,642
Available for sale securities pledged for municipal deposits, at fair value	63,573			580,756
Held to maturity securities pledged for back-to-back swaps, at amortized cost	5,038			4,645
Held to maturity securities pledged for borrowings, at amortized cost	101,981			55,497
Held to maturity securities pledged for municipal deposits, at amortized cost	282,662			167,926
Total securities pledged	$	1,263,544		$	1,008,466

Loans

Loans	3 Months Ended
	Dec. 31, 2013
Loans [Abstract]	'
Loans	'
	Loans
	The composition of the Company’s loan portfolio, excluding loans held for sale, was the following:
		December 31, 2013				September 30, 2013
	Commercial:
	Commercial & industrial	$	1,025,222			$	439,787
	Payroll finance	122,961				—
	Warehouse lending	168,776				—
	Factored receivables	146,308				—
	Equipment financing	263,770				—
	Total commercial	1,727,037				439,787
	Commercial mortgage:
	Commercial real estate	1,262,362				969,490
	Multi-family	306,533				307,547
	Acquisition, development & construction	95,787				102,494
	Total commercial mortgage	1,664,682				1,379,531
	Total commercial and commercial mortgage	3,391,719				1,819,318
	Residential mortgage	527,425				400,009
	Consumer:
	Home equity lines of credit	154,102				156,995
	Other consumer loans	53,895				36,576
	Total consumer	207,997				193,571
	Total loans	4,127,141				2,412,898
	Allowance for loan losses	(30,612		)		(28,877		)
	Total loans, net	$	4,096,529			$	2,384,021
	Total loans include net deferred loan origination costs of $1,179 at December 31, 2013 and $1,201 at September 30, 2013.
	The carrying amount of the loans acquired from Gotham Bank and legacy Sterling at December 31, 2013 totaled $1,873,076. The loans acquired consisted of loans determined to be impaired at the time of acquisition, which are accounted for in accordance with ASC Topic 310-30 Accounting for Certain Loans or Debt Securities Acquired in a Transfer (“ASC 310-30”), with a carrying amount of $14,654 and loans that were not considered impaired at the acquisition date with a carrying amount of $1,858,422. No Gotham Bank loans were deemed to be purchased credit impaired.
	Total carrying amount of the loans acquired from Gotham Bank totaled $133,493 at September 30, 2013.
	Loans acquired in the Merger that were determined to be purchased credit impaired were all considered collateral dependent loans. Therefore, estimated fair value calculations and projected cash flows included only return of principal and no interest income. There was no accretable yield associated with these loans during the three months ended December 31, 2013.
	At December 31, 2013, the Company pledged loans totaling $921,122 to the FHLB as collateral for certain borrowing arrangements. See Note 6. FHLB and Other Borrowings.
	The following tables set forth the amounts and status of the Company’s loans and troubled debt restructurings (“TDRs”) at December 31, 2013 and September 30, 2013:
		December 31, 2013
		Current				30-59				60-89			90+			Non-			Total
						days				days			days			accrual
						past due				past due			past due
	Commercial	$	1,670,399			$	22			$	54,560		$	91		$	1,965		$	1,727,037
	Commercial real estate & multi-family	1,547,358				3,816				990			—			16,731			1,568,895
	Acquisition, development & construction	91,035				311				86			273			4,082			95,787
	Residential mortgage	504,284				6,593				3,956			1,767			10,825			527,425
	Consumer	195,612				6,638				3,039			714			1,994			207,997
	Total loans	$	4,008,688			$	17,380			$	62,631		$	2,845		$	35,597		$	4,127,141
	Total TDRs included above	$	24,931			$	—			$	1,477		$	273		$	1,801		$	28,482
	Non-performing loans:
	Loans 90+ days past due and still accruing															$	2,845
	Non-accrual loans															35,597
	Total non-performing loans															$	38,442
		September 30, 2013
		Current				30-59				60-89			90+			Non-			Total
						days				days			days			accrual
						past due				past due			past due
	Commercial	$	438,818			$	178			$	2		$	289		$	500		$	439,787
	Commercial real estate & multi-family	1,263,933				1,978				2,357			1,574			7,195			1,277,037
	Acquisition, development & construction	96,306				768				—			—			5,420			102,494
	Residential mortgage	390,072				354				267			1,832			7,484			400,009
	Consumer	190,393				566				—			404			2,208			193,571
	Total loans	$	2,379,522			$	3,844			$	2,626		$	4,099		$	22,807		$	2,412,898
	Total TDRs included above	$	23,754			$	—			$	—		$	141		$	2,199		$	26,094
	Non-performing loans:
	Loans 90+ days past due and still accruing															$	4,099
	Non-accrual loans															22,807
	Total non-performing loans															$	26,906
	Activity in the allowance for loan losses for the three months ended December 31, 2013 and 2012 is summarized below:
		For the three months ended December 31, 2013
		Beginning				Charge-offs				Recoveries			Net			Provision			Ending balance
balance			charge-offs
Commercial	$	5,302			$	(528	)		$	501		$	(27	)	$	1,611		$	6,886
Commercial real estate & multi-family	9,967				(671		)		37			(634		)	659			9,992
Acquisition, development & construction	5,806				(218		)		—			(218		)	269			5,857
Residential mortgage	4,474				(270		)		7			(263		)	389			4,600
Consumer	3,328				(147		)		24			(123		)	72			3,277
Total loans	$	28,877			$	(1,834	)		$	569		$	(1,265	)	$	3,000		$	30,612
Annualized net charge-offs to average loans outstanding																		0.14		%
	For the three months ended December 31, 2012
	Beginning				Charge-offs				Recoveries			Net			Provision			Ending balance
	balance											charge-offs
Commercial	$	4,603			$	(159	)		$	120		$	(39	)	$	969		$	5,533
Commercial real estate & multi-family	7,230				(228		)		81			(147		)	533			7,616
Acquisition, development & construction	8,526				(1,594		)		5			(1,589		)	89			7,026
Residential mortgage	4,359				(950		)		51			(899		)	908			4,368
Consumer	3,564				(483		)		39			(444		)	451			3,571
Total loans	$	28,282			$	(3,414	)		$	296		$	(3,118	)	$	2,950		$	28,114
Annualized net charge-offs to average loans outstanding																		0.58		%
Management considers a loan to be impaired when, based on current information and events, it is determined that the Company will not be able to collect all amounts due according to the loan contract, including scheduled interest payments. Determination of impairment is treated the same across all classes of loans on a loan-by-loan basis, except residential mortgage loans and home equity lines of credit with an outstanding balance of $500 or less which are evaluated for impairment on a homogeneous pool basis. When management identifies a loan as impaired, the impairment is measured based on the present value of expected future cash flows, discounted at the loan’s effective interest rate, except when the sole remaining source of repayment of the loan is the operation or liquidation of the collateral. In these cases management uses the current fair value of the collateral, less selling costs when foreclosure is probable, instead of discounted cash flows. If management determines that the value of the impaired loan is less than the recorded investment in the loan (net of previous charge-offs, deferred loan fees or costs and unamortized premium or discount), impairment is generally recognized through a charge-off to the allowance for loan losses.
When the ultimate collectibility of the total principal of an impaired loan is in doubt and the loan is on non-accrual status, all payments are applied to principal, under the cost recovery method. When the ultimate collectibility of the total principal of an impaired loan is not in doubt and the loan is on non-accrual status, contractual interest is credited to interest income when received, under the cash basis method.
The following table sets forth loans evaluated for impairment by segment and the allowance evaluated by segment at December 31, 2013:
	Loans evaluated by segment														Allowance evaluated by segment
	Individually				Collectively				Purchased credit impaired loans			Total			Individually			Collectively			Total allowance for loan losses
	evaluated for				evaluated for							loans			evaluated for			evaluated for
	impairment				impairment										impairment			impairment
Commercial	$	2,272			$	1,722,128			$	2,637		$	1,727,037		$	162		$	6,724		$	6,886
Commercial real estate & multi-family	13,482				1,547,016				8,397			1,568,895			—			9,992			9,992
Acquisition, development & construction	17,928				77,859				—			95,787			524			5,333			5,857
Residential mortgage	515				523,290				3,620			527,425			—			4,600			4,600
Consumer	—				207,997				—			207,997			—			3,277			3,277
Total loans	$	34,197			$	4,078,290			$	14,654		$	4,127,141		$	686		$	29,926		$	30,612
There was no amount included in the allowance for loan losses associated with purchased credit impaired loans at December 31, 2013, as there was no further deterioration in the credit quality of these loans since the Merger date.
The following table sets forth the loans evaluated for impairment by segment and the allowance evaluated by segment at September 30, 2013:
	Loans evaluated by segment											Allowance evaluated by segment
	Individually				Collectively				Total			Individually			Collectively			Total allowance for loan losses
	evaluated for				evaluated for				loans			evaluated for			evaluated for
	impairment				impairment							impairment			impairment
Commercial	$	2,631			$	437,156			$	439,787		$	249		$	5,053		$	5,302
Commercial real estate & multi-family	14,091				1,262,946				1,277,037			803			9,164			9,967
Acquisition, development & construction	19,582				82,912				102,494			540			5,266			5,806
Residential mortgage	515				399,494				400,009			—			4,474			4,474
Consumer	2				193,569				193,571			1			3,327			3,328
Total loans	$	36,821			$	2,376,077			$	2,412,898		$	1,593		$	27,284		$	28,877
The following table presents loans individually evaluated for impairment by segment of loans at December 31, 2013 and September 30, 2013:
	31-Dec-13											30-Sep-13
	Unpaid				Recorded				Related allowance			Unpaid			Recorded			Related allowance
	principal				investment							principal			investment
	balance											balance
With no related allowance recorded:
Commercial	$	7,379			$	4,597			$	—		$	2,175		$	2,131		$	—
Commercial real estate & multi-family	28,027				21,879				—			12,451			11,820			—
Acquisition, development & construction	16,152				16,115				—			17,971			17,945			—
Residential mortgage	4,217				4,135				—			515			515			—
Consumer	—				—				—			—			—			—
Subtotal	55,775				46,726				—			33,112			32,411			—
With an allowance recorded:
Commercial	312				312				162			500			500			249
Commercial real estate & multi-family	—				—				—			3,150			2,271			803
Acquisition, development & construction	2,813				1,813				524			2,753			1,637			540
Consumer	—				—				—			2			2			1
Subtotal	3,125				2,125				686			6,405			4,410			1,593
Total	$	58,900			$	48,851			$	686		$	39,517		$	36,821		$	1,593
The following table presents the average recorded investment and interest income recognized related to loans individually evaluated for impairment by segment for the three months ended December 31, 2013 and 2012:
	31-Dec-13											31-Dec-12
	QTD				Interest				Cash-basis			QTD			Interest			Cash-basis
	average				income				interest			average			income			interest
	recorded				recognized				income			recorded			recognized			income
	investment								recognized			investment						recognized
With no related allowance recorded:
Commercial	$	3,759			$	20			$	2		$	225		$	2		$	—
Commercial real estate & multi-family	19,318				52				—			12,458			58			54
Acquisition, development & construction	17,108				148				—			13,760			87			48
Residential mortgage	4,890				—				—			7,237			43			31
Consumer	—				—				—			2,477			8			1
Subtotal	45,075				220				2			36,157			198			134
With an allowance recorded:
Commercial	314				—				—			2,410			21			6
Commercial real estate & multi-family	—				—				—			5,025			14			—
Residential mortgage	—				—				—			5,484			17			18
Acquisition, development & construction	1,932				—				—			2,919			40			—
Consumer	—				—				—			784			—			—
Subtotal	2,246				—				—			16,622			92			24
Total	$	47,321			$	220			$	2		$	52,779		$	290		$	158
Troubled Debt Restructuring:
The following tables set forth the amounts of the Company’s TDRs at December 31, 2013 and September 30, 2013:
	31-Dec-13
	Current loans				30-59				60-89			90+			Non-			Total
					days				days			days			accrual
					past due				past due			past due
Commercial	$	1,825			$	—			$	—		$	—		$	136		$	1,961
Commercial real estate & multi-family	5,301				—				—			—			62			5,363
Acquisition, development & construction	13,625				—				—			273			138			14,036
Residential mortgage	4,180				—				1,477			—			1,465			7,122
Total	$	24,931			$	—			$	1,477		$	273		$	1,801		$	28,482
Allowance for loan losses	$	759			$	—			$	—		$	16		$	—		$	775
	30-Sep-13
	Current loans				30-59				60-89			90+			Non-			Total
					days				days			days			accrual
					past due				past due			past due
Commercial	$	1,843			$	—			$	—		$	141		$	—		$	1,984
Commercial real estate & multi-family	5,305				—				—			—			—			5,305
Acquisition, development & construction	14,190				—				—			—			151			14,341
Residential mortgage	2,416				—				—			—			1,792			4,208
Consumer	—				—				—			—			256			256
Total	$	23,754			$	—			$	—		$	141		$	2,199		$	26,094
Allowance for loan losses	$	438			$	—			$	—		$	—		$	439		$	877
The Company had outstanding commitments to lend additional amounts of $0 and $4,101 to customers with loans classified as TDRs as of December 31, 2013, and September 30, 2013, respectively.
The following table presents loans by segment modified as TDRs that occurred during the three months ended December 31, 2013 and 2012:
	December 31, 2013										31-Dec-12
				Recorded investment									Recorded investment
	Number			Pre-				Post-			Number		Pre-			Post-
				modification				modification					modification			modification
Commercial	—			$	—			$	—		1		$	1,500		$	1,500
Commercial & multi-family	—			—				—			1		450			450
Acquisition, development & construction	—			—				—			2		2,723			2,723
Residential mortgage	—			—				—			1		275			275
Total restructured loans	—			$	—			$	—		5		$	4,948		$	4,948
The TDRs presented above increased the allowance for loan losses by $0 and $218 for the three months ended December 31, 2013 and 2012, respectively. There were no charge-offs as a result of the above TDRs for the respective periods.
Credit Quality Indicators
As part of the on-going monitoring of the credit quality of the Company’s loan portfolio, management tracks certain credit quality indicators including trends related to (i) the weighted-average risk grade of commercial loans, (ii) the level of classified commercial loans, (iii) the delinquency status of consumer loans (residential mortgage and HELOC), (iv) net charge-offs, (v) non-performing loans (see details above) and (vi) the general economic conditions in the greater New York metropolitan region. The Bank analyzes loans individually by classifying the loans as to credit risk, except residential mortgage loans and consumer loans which are evaluated on a homogeneous basis unless the loan balance is greater than $500. This analysis is performed on at least a quarterly basis on all criticized/classified loans. The Bank uses the following definitions of risk ratings:
1 and 2 - These grades include loans that are secured by cash, marketable securities or cash surrender value of life insurance policies.
3 - This grade includes loans to borrowers with strong earnings and cash flow and that have the ability to service debt. The borrower’s assets and liabilities are generally well matched and are above average quality. The borrower has ready access to multiple sources of funding including alternatives such as term loans, private equity placements or trade credit.
4 - This grade includes loans to borrowers with above average cash flow, adequate earnings and debt service coverage ratios. The borrower generates discretionary cash flow, assets and liabilities are reasonably matched, and the borrower has access to other sources of debt funding or additional trade credit at market rates.
5 - This grade includes loans to borrowers with adequate earnings and cash flow and reasonable debt coverage ratios. Overall leverage is acceptable and there is average reliance upon trade debt. Management has a reasonable amount of experience and modest debt owners are willing to invest available, outside capital as necessary.
6 - This grade includes loans to borrowers where there is evidence of some strain, earnings are inconsistent and volatile, and the borrowers’ outlook is uncertain. Generally such borrowers have higher leverage than those with a better risk rating. These borrowers typically have limited access to alternative sources of bank debt and may be dependent upon funding for working capital support.
7 - Special Mention (OCC definition) - Other Assets Especially Mentioned (OAEM) are loans that are currently protected but are potentially weak. Loans with special mention ratings have potential weaknesses which may, if not reviewed or corrected, weaken the asset or inadequately protect the Bank’s credit position at some future date. Such assets constitute an undue and unwarranted credit risk but not to the point of justifying a classification of substandard. The credit risk may be relatively minor yet constitute an unwarranted risk in light of the circumstances surrounding a specific asset.
8 - Substandard (OCC definition) - These loans are inadequately protected by the current sound worth and paying capacity of the obligor or of the collateral pledged, if any. Assets so classified must have a well-defined weakness that jeopardizes the liquidation of the debt. They are characterized by the distinct possibility that the Bank will sustain some loss if the deficiencies are not corrected. Loss potential, while existing in the aggregate amount of substandard assets, does not have to exist in individual assets classified as substandard.
9 - Doubtful (OCC definition) - These loans have all the weakness inherent in one classified as substandard with the added characteristics that the weakness makes collection or liquidation in full, on the basis of currently existing facts, conditions, and values, highly questionable and improbable. The possibility of loss is extremely high, but because of certain important and reasonably specific pending factors which may work to the advantage and strengthening of the asset, its classification as an estimated loss is deferred until its more exact status may be determined. Pending factors include proposed merger, acquisition, or liquidating procedures, capital injection, perfecting liens or additional collateral and refinancing plans.
10 - Loss (OCC definition) - These loans are charged-off because they are determined to be uncollectible and unbankable assets. This classification does not reflect that the asset has no absolute recovery or salvage value, but rather it is not practical or desirable to defer writing off this asset even though partial recovery may be effected in the future. Losses should be taken in the period in which they are determined to be uncollectible.
Loans that are risk-rated 1 through 6 as defined above are considered to be pass-rated loans. As of December 31, 2013 and September 30, 2013, the risk category of gross loans by segment was as follows:
	December 31, 2013											September 30, 2013
	Special				Substandard				Doubtful			Special			Substandard			Doubtful
	mention											mention
Commercial & industrial	$	20,822			$	7,644			$	312		$	3,545		$	3,855		$	365
Payroll finance	—				476				—			—			—			—
Factored receivables	3,262				—				—			—			—			—
Equipment financing	—				65				—			—			—			—
Commercial real estate & multi-family	7,448				30,132				—			7,279			24,561			227
Acquisition, development & construction	524				19,336				—			1,867			19,410			—
Residential mortgage	3,290				14,841				—			824			9,786			—
Consumer	3,488				4,531				—			15			2,891			—
Total	$	38,834			$	77,025			$	312		$	13,530		$	60,503		$	592

Deposits

Deposits	3 Months Ended
	Dec. 31, 2013
Deposits [Abstract]	'
Deposits	'
	Deposits
	Deposit balances are summarized as follows:
		December 31,		September 30,
		2013		2013
	Non-interest bearing demand	$	1,575,174	$	943,934
	Interest bearing demand	775,618		434,398
	Savings	605,168		580,125
	Money market	1,314,419		735,709
	Certificates of deposit	650,185		268,128
	Total deposits	$	4,920,564	$	2,962,294
	Municipal deposits totaled $673,656 and $757,066 at December 31, 2013 and September 30, 2013, respectively. See Note 3. Securities, for the amount of securities that were pledged as collateral for municipal deposits and other purposes.
	Summarized below are the Company’s brokered deposits included in the table above:
		December 31,		September 30,
		2013		2013
	Money market	$	59,069	$	34,571
	Reciprocal CDARs(1)	25,331		1,343
	CDARs one way	8,274		768
	Total brokered deposits	$	92,674	$	36,682
	(1)  Certificate of deposit account registry service.

Borrowings

Borrowings	3 Months Ended
	Dec. 31, 2013
Debt Instruments [Abstract]	'
Borrowings	'
	FHLB and other borrowings
	The Company’s FHLB and other borrowings and weighted average interest rates are summarized below:
		December 31, 2013				September 30, 2013
		Amount		Rate		Amount		Rate
	By type of borrowing:
	FHLB borrowings	$	489,787	2.29	%	$	442,602	2.77	%
	Commercial paper	20,658		0.31		—		—
	Repurchase agreements	61,183		0.87		20,351		0.88
	Senior Notes	98,123		5.98		98,033		5.98
	Total borrowings	$	669,751	2.64	%	$	560,986	3.26	%
	By remaining period to maturity:
	One year or less	$	119,573	0.63	%	$	158,897	0.95	%
	One to two years	96,511		0.85		78,717		1.97
	Two to three years	132,863		0.7		191		5.32
	Three to four years	200,000		4.23		202,414		4.21
	Four to five years	118,124		5.57		118,033		5.57
	Greater than five years	2,680		4.92		2,734		4.92
	Total borrowings	$	669,751	2.64	%	$	560,986	3.26	%
	As a member of the FHLB, the Bank may borrow in the form of term and overnight borrowings up to the amount of eligible mortgages and securities that have been pledged as collateral under a blanket security agreement. As of December 31, 2013 and September 30, 2013, the Bank had pledged mortgage loans totaling $921,122 and $784,422, respectively. The Bank had also pledged securities to secure borrowings, which are disclosed in Note 3. Securities. As of December 31, 2013, the Bank may increase its borrowing capacity by pledging securities and mortgage loans not required to be pledged for other purposes with a market value of $679,715.
	FHLB borrowings which are putable quarterly at the discretion of the FHLB were $200,000 as of December 31, 2013 and September 30, 2013. These borrowings have a weighted average remaining term to the contractual maturity dates of approximately 3.31 years and 3.56 years, respectively, and a weighted average interest rate of 4.23% at each of December 31, 2013 and September 30, 2013.
	The Bank had two $10,000 repurchase agreements with a financial institution at December 31, 2013 and September 31, 2013 and in connection with the Merger assumed repurchase agreements with a balance of $40,919, a weighted average interest rate of 0.35% and a weighed average term to maturity of 14 days. At December 31, 2013, total repurchase agreements outstanding were $61,183. The Bank has pledged investment securities as collateral for these borrowings (see Note 3. Securities).
	On July 2, 2013 the Company issued $100,000 principal amount of 5.50% fixed rate Senior Notes through a private placement at a discount of 1.75%. The cost of issuance was $303, and at December 31, 2013 and September 30, 2013 the unamortized discount was $1,877 and $1,967, respectively, which will be accreted to interest expense over the life of the Senior Notes, resulting in an all-in cost of 5.98%. Interest is due semi-annually in arrears on January 2 and July 2 of each year beginning January 2, 2014 until maturity on July 2, 2018. The Senior Notes were issued under an indenture (the “Indenture”) between the Company and U.S. Bank National Association, as trustee.
	The Senior Notes are unsecured obligations of the Company and rank equally with all other unsecured unsubordinated indebtedness, and will be effectively subordinated to any secured indebtedness to the extent of the value of the collateral securing such indebtedness, and structurally subordinated to the existing and future indebtedness of the Company’s subsidiaries.
	The indenture includes provisions that, among other things, restrict the Company’s ability to dispose of or issue shares of voting stock of a principal subsidiary bank (as defined in the Indenture) or transfer the entirety of or a substantial amount of the Company’s assets or merge or consolidate with or into other entities, without satisfying certain conditions.
	The Senior Notes will not be registered under the Securities Act and may not be offered or sold in the U.S. absent registration or an applicable exemption from registration requirements.

Subordinated_Debentures_Subord

Subordinated Debentures Subordinated Debentures	3 Months Ended
	Dec. 31, 2013
Subordinated Debentures [Abstract]	'
Subordinated Borrowings Disclosure [Text Block]	'
	Subordinated Debentures
		31-Dec-13		30-Sep-13
	Subordinated debentures	$	25,774	$	—
	Premium recorded to reflect fair value at acquisition date	745		—
		$	26,519	$	—
	In February 2002, legacy Sterling issued $25,000 of trust preferred capital securities. The capital securities which are due March 31, 2032 and bear interest at 8.375%, were issued by Sterling Bancorp Trust I, a wholly-owned, non-consolidated statutory business trust. The trust was formed with initial capitalization of common stock and for the exclusive purpose of issuing the capital securities. The trust used the proceeds from the issuance of the capital securities to acquire $25,774 junior subordinated debenture securities that pay interest at 8.375% issued by the Company. The Company is not considered the primary beneficiary of the trust (which is a VIE); therefore, the trust is not consolidated in the Company’s financial statements, but rather the subordinated debentures are recorded as a liability. The debt securities are due concurrently with the capital securities, which may be redeemed at a price equal to their principal amount plus interest accrued to the date of redemption at par. The Company may also reduce outstanding capital securities, through open market purchases. At December 31, 2013 the Company held $1,013 par value of the capital securities as available for sale investment securities.
	The capital securities held by the Company are considered to be outstanding for the payment of dividends but are considered to be redeemed for the calculation of regulatory capital ratios. The $23,987 of capital securities not held by the Company is included in Tier 1 capital for regulatory capital purposes as allowed by the Federal Reserve Board.
	The Company has the right to defer payments of interest on the debt securities at any time or from time to time for a period of up to 20 consecutive quarterly periods with respect to each deferral period. Under the terms of the debt securities, in the event that under certain circumstances there is an event of default under the debt securities or the Company has elected to defer interest on the debt securities, the Company may not, with certain exceptions, declare or pay any dividends or distributions on its capital stock or purchase or acquire any of its capital stock.
	Payments of distributions on the capital securities and payments on redemption of the capital securities are guaranteed by the Company on a limited basis. The Company also entered into an agreement as to expenses and liabilities pursuant to which it agreed, on a subordinated basis, to pay any costs, expenses or liabilities of the trust other than those arising under the capital securities. The obligations of the Company under the debt securities within the related indenture, the trust agreement establishing the trust, the guarantee and the agreement as to expenses and liabilities, in the aggregate, constitute a full and unconditional guarantee by the Company of the trust’s obligations under the capital securities.
	The premium on the securities represents the adjustment to reflect the fair value of the securities at the date of the Merger. This premium will be amortized as a reduction of interest expense over the remaining term of the capital securities on a level yield basis.
	We anticipate that we will redeem the capital securities prior to June 30, 2014.

Guarantors_Obligations_Under_G

Guarantor's Obligations Under Guarantees	3 Months Ended
	Dec. 31, 2013
Guarantees [Abstract]	'
Guarantor's Obligations Under Guarantees	'
	Guarantor’s Obligations Under Guarantees
	Most letters of credit issued by or on behalf of the Company are standby letters of credit. Standby letters of credit are commitments issued by the Company on behalf of its customer/obligor in favor of a beneficiary that specify an amount the Company can be called upon to pay upon the beneficiary’s compliance with the terms of the letter of credit. These commitments are primarily issued in favor of local municipalities to support the obligor’s completion of real estate development projects. The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loan facilities to customers.
	As of December 31, 2013, the Company had $79,811 in outstanding letters of credit, of which $22,218 are cash secured and $14,689 were secured by other collateral. The carrying values of these obligations are not considered material.

Contingencies

Contingencies	3 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Contingencies	'
	Contingencies
	Certain premises and equipment are leased under operating leases with terms expiring through 2033. The Company has the option to renew certain of these leases for additional terms.
	Litigation
	The Company and the Bank are involved in a number of judicial proceedings concerning matters arising from conducting their business activities. These proceedings include actions brought against the Company and the Bank with respect to corporate matters and transactions in which the Company and the Bank were involved. In addition, the Company and the Bank may be requested to provide information or otherwise cooperate with government authorities in the conduct of investigations of other persons or industry groups.
	There can be no assurance as to the ultimate outcome of a legal proceeding; however, the Company and the Bank have generally denied, or believe they have meritorious defenses and will deny, liability in all significant litigation pending against us, including the matters described below, and we intend to defend vigorously each case, other than matters we describe as having settled. We accrue a liability for legal claims when payments associated with the claims become probable and the costs can be reasonably estimated. The actual costs of resolving legal claims may be substantially higher or lower than the amounts accrued for those claims.
	As previously disclosed on April 9, 2013, the first of seven actions, captioned Altman v. Sterling Bancorp, et al., Index No. 651263/2013 (N.Y. Sup. Ct., N.Y. County, 2013), was filed in the New York State Supreme Court, New York County, on behalf of a putative class of shareholders against legacy Sterling, its directors, and the Company.  On May 17, 2013, the seven actions were consolidated under the caption In re Sterling Shareholders Litigation, Index No. 651263/2013 (N.Y. Sup. Ct., N.Y. County, 2013). On June 21, 2013, the lead plaintiffs filed a consolidated and amended class action complaint alleging that legacy Sterling’s board of directors breached its fiduciary duties by agreeing to the Merger transaction described in Note 2 and by failing to disclose all material information to shareholders. The consolidated and amended complaint also alleged that the Company aided and abetted those alleged fiduciary breaches. The action sought, among other things, equitable relief and/or money damages.
	Also as previously disclosed, on June 5, 2013, a substantially similar litigation was filed in the United States District Court for the Southern District of New York, captioned Miller v. Sterling Bancorp, et al., No. 13‑3845 (S.D. N.Y. 2013), against legacy Sterling, its directors, and the Company on behalf of the same putative class of legacy Sterling shareholders. The complaint alleged the same breach of fiduciary duty and aiding and abetting claims against defendants, and also alleged defendants’ preliminary proxy statement was inaccurate or incomplete in violation of Sections 14(a) and 20(a) of the Securities Exchange Act of 1934, as amended.
	In terms of material developments on the status of proceedings, on September 12, 2013, the Company and the parties entered into a memorandum of understanding regarding the settlement of the lawsuits under which each of the actions will be dismissed with prejudice. Pursuant to the terms of the settlement, the Company agreed to make certain supplemental disclosures related to the Merger.  The settlement is subject to, among other things, entry into final, definitive documentation and approval by the New York State Supreme Court. We believe that the ultimate liability, if any, with respect to these and other claims and legal actions will not have a material effect on our financial position or on our results of operations.

Earnings_Per_Common_Share

Earnings Per Common Share	3 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Earnings Per Common Share	'
	Earnings Per Common Share
	The number of shares used in the computation of basic earnings per share excludes unallocated ESOP shares and unvested shares of restricted stock that are not participating securities.
	Common stock equivalent shares are incremental shares (computed using the treasury stock method) that would have been outstanding if all potentially dilutive stock options and unvested recognition and retention plan shares were exercised or became vested during the periods presented.
	Basic earnings per common share are computed as follows:
		For the three months ended December 31,
		2013			2012
	Weighted average common shares outstanding (basic)	70,493,305			43,637,315
	Net (loss) income	$	(14,002	)	$	7,020
	Basic (loss) earnings per common share	(0.20		)	0.16
	Diluted earnings per common share are computed as follows:
		For the three months ended December 31,
		2013			2012
	Weighted average common shares outstanding (basic)	70,493,305			43,637,315
	Effect of common stock equivalents	—			83,776
	Weighted average common shares outstanding (diluted)	70,493,305			43,721,091
	Net (loss) income	$	(14,002	)	$	7,020
	Diluted (loss) earnings per common share	(0.20		)	0.16
	As of December 31, 2013 and 2012, 2,025,501 and 1,358,812 weighted average shares that could be exercised under stock option plans were anti-dilutive for the three month period, respectively. Anti-dilutive shares are not included in the determination of diluted earnings per share.

Other_Noninterest_expense_Othe

Other Non-interest expense Other Non-interest expense	3 Months Ended
	Dec. 31, 2013
Other Non-Interest Expense [Abstract]	'
Other non-interest expense [Text Block]	'
	Other Non-Interest Expense
	Other non-interest expense items are presented in the following table. Components exceeding 1% of the aggregate of total net interest income and total non-interest income are presented separately.
		December 31,
		2013		2012
	Other non-interest expense:
	Advertising and promotion	$	309	$	244
	Professional fees	1,818		1,215
	Data and check processing	595		649
	Other	4,733		2,565
	Total other non-interest expense	$	7,455	$	4,673

StockBased_Compensation

Stock-Based Compensation	3 Months Ended
	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Stock-Based Compensation	'
	Stock-Based Compensation
	The Company has three active stock-based compensation plans as described below. Total compensation expense that was charged against income for those plans was $991 and $384, for the three months ended December 31, 2013 and 2012, respectively. There was no income tax benefit realized for the three months ended December 31, 2013 or 2012.
	Active Stock-Based Compensation Plans
	The Company’s 2012 Stock Incentive Plan (the “2012 Plan”), is a shareholder-approved plan that permits the grant of stock options, stock appreciation rights, restricted stock (both time-based and performance-based), restricted stock units, performance units, deferred stock and other stock-based awards for up to 561,995 shares of common stock as of December 31, 2013. Stock option awards are generally granted with an exercise price equal to the market price of the Company’s common stock at the date of grant, and other awards are granted with a fair value equal to the market price of the Company’s common stock at the date of grant; those awards generally vest in equal installments annually on the anniversary date and have total vesting periods ranging from 2 to 5 years and stock options have 10 year contractual terms. The Company has a policy of using shares held as treasury stock to satisfy its stock-based compensation stock issuances. Currently, the Company has a sufficient number of treasury shares to satisfy expected stock-based compensation issuances.
	The Company’s 2004 Stock Incentive Plan (the “2004 Plan”), is a shareholder-approved plan that permits the grant of stock options to its employees for up to 20,674 shares of common stock as of December 31, 2013. Option awards are generally granted with an exercise price equal to the market price of the Company’s common stock at the date of grant and other awards are granted with a fair value equal to the market price of the Company’s common stock at the date of grant; those awards generally vest in equal installments annually on the anniversary date and have total vesting periods ranging from 2 to 5 years and stock options have 10 year contractual terms. The Company has a policy of using shares held as treasury stock to satisfy its stock-based compensation stock issuances.
	The Company’s 2004 Restricted Stock Plan, which historically has been referred to as the Recognition and Retention Plan (“RRP”), provides for the issuance of shares to directors and officers. Compensation expense is recognized on a straight-line basis over the vesting period of the awards based on the fair value of the stock at issue date. RRP shares vest annually on the anniversary of the grant date over the vesting period. Total shares remaining that are authorized and available for future grant under the RRP are 77 at December 31, 2013.
	Under the 2004 Plan and the RRP each grant of stock or restricted stock counts as one share deducted from the applicable plan for every one share delivered under those awards. Under the 2012 Plan each share of restricted stock, (or non-vested stock awards), is counted as 3.6 shares deducted from the plan for every one share delivered under those awards. Under the 2012 Plan, shares awarded under other grants, including stock options, stock appreciation rights, performance units, deferred stock and other stock awards will count as one share deducted from the plan for every one share delivered under those awards.
	In connection with the Merger, the Company granted 110,470 common stock options at an exercise price of $14.25 per share pursuant to a Registration Statement on Form S-8 under which the Company assumed all outstanding fully vested legacy Sterling stock options. Substantially all of these options expire March 15, 2017. During the quarter ended December 31, 2013, 3,156 of these awards were canceled and such shares are again available for grant. The Company also granted 95,991 shares under the Sterling Bancorp 2013 Employment Inducement Award Plan to certain executive officers of legacy Sterling. In addition, the Company issued 255,973 shares of restricted stock from shares available under the Company’s 2012 Plan to certain executives of legacy Sterling. The weighted average grant date fair value was $11.72 per share and the restricted stock awards vest in equal annual installments on the anniversary date over a three-year period.
	The fair value of each stock option award is estimated on the date of grant using a closed form option valuation (Black-Scholes) model that uses the assumptions noted in the table below. Expected volatility is based on the historical volatility of the Company’s common stock. The expected term of options granted is based on historical data and represents the period of time that options granted are expected to be outstanding, which takes into account that the options are not transferable. The risk-free interest rate for the expected term of the option is based on the U.S. Treasury yield curve in effect at the date of grant.
	The fair value of options granted was determined using the following weighted average assumptions as of the grant date:
		For the three months ended December 31,
		2013		2012
	Risk-free interest rate	1.74	%	0.96	%
	Expected stock price volatility	26.5	%	40.8	%
	Dividend yield (1)	2.05	%	2.61	%
	Expected term in years	5.75		5.75
	(1) Represents the approximate annualized cash dividend rate paid with respect to a share of common stock at or near the grant date.
	The following table summarizes the combined activity in the Company’s stock-based compensation plans for the three months ended December 31, 2013:
				Non-vested stock awards/stock units outstanding				Stock options outstanding
		Shares available for grant		Number of shares		Weighted average grant date fair value		Number of shares		Weighted average exercise price
	Balance at September 30, 2013	2,066,184		209,697		$	8.73	2,114,509		$	10.71
	Grants associated with legacy Sterling Merger(1)	(921,503	)	351,964		11.72		104,152		14.25
	Granted (1)	(595,435	)	101,078		11.36		249,862		11.36
	Stock awards vested	—		(44,523	)	8.73		—		—
	Exercised	—		—		—		(338,177	)	12.16
	Forfeited	36,656		—		—		(36,656	)	8.59
	Balance at December 31, 2013	585,902		618,216		$	10.83	2,093,690		$	10.77
	Exercisable at December 31, 2013							1,293,662		$	11.64
	(1) Reflects certain non-vested stock awards that count as 3.6 shares deducted from the plan for every one share delivered under these awards.
	The weighted average fair value of options granted was $2.49 and $2.74 for the three months ended December 31, 2013 and 2012, respectively.
	As of December 31, 2013, there was $1,704 of total unrecognized compensation expense related to non-vested stock options granted under the Company’s stock-based compensation plans. The expense is expected to be recognized over a weighted average period of 2.06 years.
	As of December 31, 2013, there was $5,892 of total unrecognized compensation expense related to non-vested restricted shares granted under the 2012 Plan, the RRP and the Registration Statement on Form S-8. The expense is expected to be recognized over a weighted average period of 2.49 years.
	There were no stock-based award modifications for the three months ended December 31, 2013 and 2012.

Pension_and_Other_Post_Retirem

Pension and Other Post Retirement Plans	3 Months Ended
	Dec. 31, 2013
Compensation Related Costs [Abstract]	'
Pension and Other Post Retirement Plans	'
	Pension and Other Post Retirement Plans
	Net pension and post-retirement expense, which is recorded in compensation and employee benefits expense in the consolidated statements of operations, is comprised of the following:
		Pension plan						Other post
								retirement plans
		For the three months ended December 31,						For the three months ended December 31,
		2013			2012			2013		2012
	Service cost	$	—		$	—		$	12	$	11
	Interest cost	402			363			34		31
	Expected return on plan assets	(672		)	(616		)	—		—
	Amortization of net transition obligation	—			—			6		6
	Amortization of prior service cost	—			—			12		12
	Amortization of (gain) or loss	97			516			—		(6		)
	Charge for settlement of a portion of defined benefit plan	2,743			—			—		—
	Total cost	$	2,570		$	263		$	64	$	54
	As of December 31, 2013, no contributions had been made in this fiscal year to the pension plan. The Company has not yet determined if additional contributions will be made during the remainder of fiscal year 2014. The Company’s pension plan liabilities were $31,705 at September 30, 2013. During the quarter ended December 31, 2013, the Company settled a portion of its pension plan liability through the acquisition of annuity contracts from a nationally recognized insurance company in the amount of $13,698, which together with the net amount of benefits paid and interest cost reduced the pension plan liability to $17,980 at December 31, 2013.   The Plan's over funded status decreased from $3,712 at September 30, 2013 to $3,489 at December 31, 2013. In connection with the settlement discussed above, the Company incurred accelerated amortization of its accumulated other comprehensive loss on the defined benefit plan in the amount of $2,743, which was realized through earnings as part of Non-interest expense - Compensation and benefits during the three months ended December 31, 2013.
	The Company has also established a non-qualified Supplemental Executive Retirement Plan (“SERP”) to provide certain executives with supplemental retirement benefits in addition to the benefits provided by the pension plan due to amounts limited by the Internal Revenue Code of 1986, as amended (“IRS Code”). The periodic pension expense for the supplemental plan amounted to $18 for the three months ended December 31, 2013 and $13 for the three months ended December 31, 2012. The liability for the SERP was $1,203 and $1,238 at December 31, 2013 and September 30, 2013, respectively. For the three months ended December 31, 2013 and 2012 there was $0 and $9, respectively, in contributions to fund benefit payments related to the SERP.
	On October 30, 2013,  the Company terminated its employee stock ownership plan (“ESOP”).  In accordance with the provisions of the plan, all participants received contributions for calendar year 2013 and became 100% vested in their accounts.  On February 4, 2014, the ESOP held 499,330 shares of the Company’s common stock.  Of these shares 488,403 were used to retire the ESOP trust outstanding loan obligation, which was $5,983 including accrued interest.  In accordance with the provisions of the plan the remaining 10,927 shares were allocated ratably to ESOP participants.  The Company incurred ESOP expense of $268 during the three months ended December 31, 2013 which was recorded in Non-interest expense - Compensation and benefits.
	In connection with the Merger, the Company assumed the following pension liabilities on October 31, 2013:
	•	A liability for the legacy Sterling Supplemental Executive Retirement Plan (the “legacy Sterling SERP”) for designated participants. The balance of the liability assumed was $41,412 and was settled through a cash payment to the designated participants on November 8, 2013.
	•	A liability for the legacy Sterling/Sterling National Bank employees’ Retirement Plan (the “legacy Sterling Qualified Plan”).  The legacy Sterling Qualified Plan is a defined benefit plan that covers eligible employees of legacy Sterling and legacy Sterling National Bank and certain of its subsidiaries who were hired prior to January 3, 2006 and who attained age 21 prior to January 3, 2007. Effective October 31, 2013, the Qualified Plan was amended and the accrued benefit of each eligible actively employed participant that had not yet commenced benefits was increased by approximately 4.4% and the accrual of future service benefits ceased.  At December 31, 2013, the legacy Sterling Qualified Plan had assets of approximately $73 million and a projected benefit obligation of approximately $54 million. The prepaid pension asset related to the legacy Sterling Qualified Plan is recorded in other assets on the Company’s balance sheet. For the three months ended December 31, 2013, the Company recognized an expense of $33 related to the legacy Sterling Qualified Plan.
	•	A liability for the legacy Sterling life insurance benefits provided to certain officers.  The level of coverage provided is determined upon years of service with legacy Sterling and the Company and the employee’s date of retirement.  The Company’s post-retirement benefit plan is unfunded and the liability at December 31, 2013 was $8,798. For the three months ended December 31, 2013, the Company recognized an expense of $70 related to legacy Sterling’s post-retirement benefit plan.

Derivatives

Derivatives	3 Months Ended
	Dec. 31, 2013
Derivative Instruments and Hedges, Assets [Abstract]	'
Derivatives	'
	Derivatives
	The Company purchased two interest rate caps in fiscal 2010 to assist in offsetting a portion of interest rate exposure should short- term rate increases lead to rapid increases in general levels of market interest rates on deposits. These caps are linked to LIBOR and have strike prices of 3.5% and 4.0%. These caps are stand alone derivatives and therefore changes in fair value are reported in current period earnings. Losses recognized in earnings were $0 and $1 at December 31, 2013 and 2012, respectively. The fair value of the interest rate caps at December 31, 2013, is reflected in other assets with a corresponding credit (charge) to income recorded as a gain (loss) to non-interest income.
	The Company has entered into certain interest rate swap contracts that are not designated as hedging instruments. These derivative contracts relate to transactions in which the Company enters into an interest rate swap with a customer while at the same time entering into an offsetting interest rate swap with another financial institution. In connection with each swap transaction, the Company agrees to pay interest to the customer on a notional amount at a variable interest rate and receive interest from the customer on a similar notional amount at a fixed interest rate. At the same time, the Company agrees to pay another financial institution the same fixed interest rate on the same notional amount and receive the same variable interest rate on the same notional amount. The transaction allows the Company’s customer to effectively convert a variable rate loan to a fixed rate. Because the Company acts as an intermediary for its customer, changes in the fair value of the underlying derivative contracts for the most part offset each other and do not significantly impact the Company’s results of operations.
	The Company pledged collateral to another financial institution in the form of investment securities with an amortized cost of $5,038 and a fair value of $4,572 as of December 31, 2013. The Company does not typically require its commercial customers to post cash or securities as collateral on its program of back-to-back swaps. However, certain language is written into the International Swaps and Derivatives Association agreement and loan documents where, in default situations, the Company is allowed to access collateral supporting the loan relationship to recover any losses suffered on the derivative asset or liability. The Company may need to post additional collateral in the future in proportion to potential increases in unrealized loss positions.
	Summary information regarding these derivatives is presented below:
		Notional			Average	Weighted		Weighted average	Fair value
		amount			maturity (in years)	average		variable rate
						fixed rate
	At December 31, 2013
	Interest rate caps	$	50,000		0.92	3.75	%	NA	$	—
	Third-party interest rate swaps	53,666			5.51	4.22		1 m Libor + 2.45	621
	Customer interest rate swaps	(53,666		)	5.51	4.22		1 m Libor + 2.45	(621		)
	At September 30, 2013
	Interest rate caps	$	50,000		1.18	3.75	%	NA	$	—
	Third-party interest rate swaps	54,180			5.76	4.22		1 m Libor + 2.45	997
	Customer interest rate swaps	(54,180		)	5.76	4.22		1 m Libor + 2.45	(997		)
	The Company enters into various commitments to sell real estate loans in the secondary market. Such commitments are considered to be derivative financial instruments; however, the fair value of these commitments is not material.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair value measurements	'
	Fair Value Measurements
	Fair value is the exchange price that would be received for an asset or paid to transfer a liability (exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. There are three levels of inputs that may be used to measure fair values.
	Level 1 Inputs – Unadjusted quoted prices in active markets for identical assets and liabilities that the reporting entity has the ability to access at the measurement date.
	Level 2 Inputs – Inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. These might include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (such as interest rates, volatilities, prepayment speeds, credit risk etc.) or inputs that are derived principally from or corroborated by market data by correlation or other means.
	Level 3 Inputs – Unobservable inputs for determining the fair values of assets or liabilities that reflect an entity’s own assumptions about the assumptions that market participants would use in pricing the assets or liabilities.
	In general, fair value is based on quoted market prices, when available. If quoted market prices in active markets are not available, fair value is based on internally developed models that primarily use, as inputs, observable market-based parameters. Valuation adjustments may be made to ensure that financial instruments are recorded at fair value.  These adjustments may include amounts to reflect counterparty credit quality and the Company’s creditworthiness, among other things, as well as unobservable parameters. Any such valuation adjustments are applied consistently over time. The Company’s valuation methodologies may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values. While management believes the Company’s valuation methodologies are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value at the reporting date. Furthermore, the reported fair value amounts have not been comprehensively revalued since the presentation dates, and therefore, estimates of fair value after the balance sheet date may differ significantly from the amounts presented herein. A more detailed description of the valuation methodologies used for assets and liabilities measured at fair value is set forth below. Transfers between levels of the fair value hierarchy are recognized on the actual date of the event or circumstances that caused the transfer, which generally coincides with the Company’s monthly and/or quarterly valuation process.
	Investment Securities Available for Sale
	The majority of the Company’s available for sale investment securities  are reported at fair value utilizing Level 2 inputs. For these securities, the Company obtains fair value measurements from an independent pricing service. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury yield curve, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the securities’ terms and conditions, among other things.
	The Company reviews the prices supplied by the independent pricing service, as well as their underlying pricing methodologies, for reasonableness and to ensure such prices are aligned with traditional pricing matrices. In general, the Company does not purchase investment securities that have a complicated structure. The Company’s entire portfolio consists of traditional investments, nearly all of which are mortgage pass-through securities, state and municipal general obligation or revenue bonds, U.S. agency bullet and callable securities and corporate bonds. Pricing for such instruments is fairly generic and is easily obtained. From time to time, the Company validates, on a sample basis, prices supplied by the independent pricing service by comparison to prices obtained from third-party sources or derived using internal models.
	The Company reports the fair value of private label collateralized mortgage obligations or “CMOs” with a rating from a national recognized bond rating agency of below investment grade using Level 3 inputs. As of December 31, 2013, these securities have an amortized cost of $3,362 and a fair value of $3,356. In determining the fair value of these securities the Company utilized unobservable inputs which reflect assumptions regarding the inputs that management believes market participants would use in pricing these securities in an orderly market. Significant increases (decreases) in any of the unobservable inputs would result in a significantly lower (higher) fair value measurement of the securities. Present value estimated cash flow models were used to discount expected cash flows at the interest rate reflective of similarly structured securities in an orderly market. These securities have a weighted average coupon rate of 2.76%, a weighted average life of 3.37 years, and a weighted average twelve month constant prepayment rate history of 15.39. The three private label CMOs with sub-investment grade ratings have a weighted average twelve month constant default rate of 3.64%.
	The credit ratings of private label CMO securities at December 31, 2013 were as follows:
		Amortized			Fair
		cost			value
	Credit rating:
	Baa1	$	187		$	188
	Ba1	100			95
	B1	1,790			1,786
	B3	1,285			1,287
	Total private label CMOs	$	3,362		$	3,356
	Derivatives
	The fair values of derivatives are based on valuation models using current market terms (including interest rates and fees), the remaining terms of the agreements and the credit worthiness of the counter party as of the measurement date (Level 2). The Company’s derivatives consist of two interest rate caps and twelve interest rate swaps. See Note 14. Derivatives.
	Commitments to Sell Real Estate Loans
	The Company enters into various commitments to sell real estate loans in the secondary market. Such commitments are considered to be derivative financial instruments and therefore are carried at estimated fair value on the consolidated balance sheets. The estimated fair values of these commitments were generally calculated by reference to quoted prices in secondary markets for commitments to sell to certain government sponsored agencies. The fair values of these commitments generally result in a Level 2 classification. The fair value of these commitments is not material.
	A summary of assets and liabilities at December 31, 2013 measured at estimated fair value on a recurring basis is as follows:
		December 31, 2013
		Fair value			Level 1 inputs				Level 2 inputs			Level 3 inputs
	Assets:
	Investment securities available for sale:
	Residential mortgage-backed securities:
	Fannie Mae	$	234,434		$	—			$	234,434		$	—
	Freddie Mac	108,736			—				108,736			—
	Ginnie Mae	14,826			—				14,826			—
	CMO/Other MBS	135,909			—				135,909			—
	Private label CMOs	3,356			—				—			3,356
	Total residential mortgage-backed securities	497,261			—				493,905			3,356
	Other securities:
	US Government	4,854			—				4,854			—
	Federal agencies	252,609			—				252,609			—
	Corporate bonds	197,763			—				197,763			—
	State and municipal	133,094			—				133,094			—
	Trust preferred securities	67,732			—				67,732			—
	Total other securities	656,052			—				656,052			—
	Total investment securities available for sale	1,153,313			—				1,149,957			3,356
	Interest rate caps and swaps	621			—				621			—
	Total assets measured at estimated fair value on a recurring basis	$	1,153,934		$	—			$	1,150,578		$	3,356
	Liabilities:
	Interest rate swaps	$	621		$	—			$	621		$	—
	Total liabilities measured at estimated fair value on a recurring basis	$	621		$	—			$	621		$	—
	A summary of assets and liabilities at September 30, 2013 measured at estimated fair value on a recurring basis is as follows:
		September 30, 2013
		Fair value			Level 1 inputs				Level 2 inputs			Level 3 inputs
	Assets:
	Investment securities available for sale:
	Residential mortgage-backed securities:
	Fannie Mae	$	211,438		$	—			$	211,438		$	—
	Freddie Mac	67,629			—				67,629			—
	Ginnie Mae	3,462			—				3,462			—
	CMO/Other MBS	163,041			—				163,041			—
	Private label CMOs	3,613			—				—			3,613
	Total residential mortgage-backed securities	449,183			—				445,570			3,613
	Other securities:
	Federal agencies	261,547			—				261,547			—
	Corporate debt securities	114,933			—				114,933			—
State and municipal	128,730			—				128,730			—
Total other securities	505,210			—				505,210			—
Total investment securities available for sale	954,393			—				950,780			3,613
Interest rate caps and swaps	997			—				997			—
Total assets measured at estimated fair value on a recurring basis	$	955,390		$	—			$	951,777		$	3,613
Liabilities:
Interest rate swaps	$	997		$	—			$	997		$	—
Total liabilities measured at estimated fair value on a recurring basis	$	997		$	—			$	997		$	—
There were no transfers between Level 1 and Level 2 inputs during the three months ended December 31, 2013 and 2012.
The changes in Level 3 assets measured at fair value on a recurring basis are summarized below:
	Changes in Level 3 assets for the three months ended December 31, 2013			Changes in Level 3 assets for the three months ended December 31, 2012
Balance at September 30,	$	3,613		$	4,630
Paydowns	(275		)	(325		)
Amortization, net	—			6
OTTI	—			(14		)
Change in fair value	18			63
Balance at December 31,	$	3,356		$	4,360
Changes in fair value are included as part of net unrealized holding gains (losses) on securities available for sale net of related tax expense on the Consolidated Statements of Comprehensive (Loss) Income.
The following categories of financial assets are not measured at fair value on a recurring basis, but are subject to fair value adjustments in certain circumstances:
Loans Held for Sale and Impaired Loans
Mortgage loans originated and intended for sale in the secondary market are carried at the lower of aggregate cost or fair value as determined by outstanding commitments from investors. Fair value of loans held for sale is determined using quoted prices for similar assets (Level 2 inputs).
When mortgage loans held for sale are sold with servicing rights retained, the carrying value of mortgage loans sold is reduced by the amount allocated to the value of the servicing rights which is equal to its fair value. Gains and losses on sales of mortgage loans are based on the difference between the selling price and the carrying value of the related loan sold.
The Company may record adjustments to the carrying value of loans based on fair value measurements for partial charge-offs of the uncollectible portions of these loans. These adjustments also include certain impairment amounts for collateral dependent loans calculated in accordance with FASB ASC Topic 310 – Receivables, when establishing the allowance for loan losses. Impairment amounts are generally based on the fair value of the underlying collateral supporting the loan and, as a result, the carrying value of the loan less the calculated impairment amount applicable to that loan does not necessarily represent the fair value of the loan. Real estate collateral is valued using independent appraisals or other indications of value based on recent comparable sales of similar properties or assumptions generally observable by market participants. However, due to the substantial judgment applied and limited volume of activity as compared to other assets, fair value is based on Level 3 inputs. Estimates of fair value used for collateral supporting commercial loans generally are based on assumptions not observable in the market place and are also based on Level 3 inputs. Impaired loans are evaluated on at least a quarterly basis for additional impairment and their carrying values are adjusted as needed. Loans subject to non-recurring fair value measurements were $33,511 and $35,230 (which equals the carrying value less the allowance for loan losses allocated to these loans) at December 31, 2013 and September 30, 2013, respectively. Changes in fair value recognized in provisions on loans held by the Company were $56 and $1,815 for the three months ended December 31, 2013 and 2012, respectively.
When valuing impaired loans that are collateral dependent, the Company charges-off the difference between the recorded investment in the loan and the appraised value, which is generally less than 12 months old. A discount for estimated costs to dispose of the asset is used when evaluating the impaired loans.
A summary of impaired loans at December 31, 2013 measured at estimated fair value on a non-recurring basis is the following:
	December 31, 2013
	Fair value			Level 1 inputs				Level 2 inputs			Level 3 inputs
Commercial	$	311		$	—			$	—		$	311
Commercial real estate and multi-family	2,332			—				—			2,332
Acquisition, development & construction	2,254			—				—			2,254
Total impaired loans measured at fair value	$	4,897		$	—			$	—		$	4,897
A summary of impaired loans at September 30, 2013 measured at estimated fair value on a non-recurring basis is the following:
	September 30, 2013
	Fair value			Level 1 inputs				Level 2 inputs			Level 3 inputs
Commercial	$	500		$	—			$	—		$	500
Commercial real estate and multi-family	3,672			—				—			3,672
Acquisition, development & construction	1,839			—				—			1,839
Consumer loans	2			—				—			2
Total impaired loans measured at fair value	$	6,013		$	—			$	—		$	6,013
Mortgage Servicing Rights
When mortgage loans are sold with servicing retained, servicing rights are initially recorded at fair value with the income statement effect recorded in net gain on sales of loans. Fair value is based on market prices for comparable mortgage servicing contracts, when available, or alternatively, is based on a valuation model that calculates the present value of estimated future net servicing income.
The Company utilizes the amortization method to subsequently measure the carrying value of its servicing rights. In accordance with FASB ASC Topic 860 - Transfers and Servicing, the Company must record impairment charges on a non-recurring basis, when the carrying value exceeds the estimated fair value. To estimate the fair value of servicing rights, the Company utilizes a third-party, which on a quarterly basis, considers the market prices for similar assets and the present value of expected future cash flows associated with the servicing rights. Assumptions utilized include estimates of the cost of servicing, loan default rates, an appropriate discount rate and prepayment speeds. The determination of fair value of servicing rights relies upon Level 3 inputs. The fair value of mortgage servicing rights at December 31, 2013 and September 30, 2013 was $1,863 and $1,978, respectively.
Assets Taken in Foreclosure of Defaulted Loans
Assets taken in foreclosure of defaulted loans are initially recorded at fair value less costs to sell when acquired, which establishes a new cost basis. These assets are subsequently accounted for at the lower of cost or fair value less costs to sell and are primarily comprised of commercial and residential real estate property and upon initial recognition, were re-measured and reported at fair value through a charge-off to the allowance for loan losses based on the fair value of the foreclosed asset. The fair value is generally determined using appraisals or other indications of value based on recent comparable sales of similar properties or assumptions generally observable in the market place. Adjustments are routinely made in the appraisal process by the independent appraisers to adjust for differences between comparable sales and income data available. The fair value is derived using Level 3 inputs. Appraisals are reviewed by our credit department, our external loan review consultant and verified by officers in our credit administration area. Assets taken in foreclosure of defaulted loans subject to non-recurring fair value measurement were $7,566 and $6,022 at December 31, 2013 and September 30, 2013, respectively. There were write-downs of $224 and $158 related to changes in fair value recognized through income for other real estate owned held by the Company during the three months ending December 31, 2013 and 2012, respectively.
Significant Unobservable Inputs to Level 3 Measurements
The following table presents quantitative information about significant unobservable inputs used in the fair value measurements for Level 3 assets at December 31, 2013:
Non-recurring fair value measurements		Fair value			Valuation technique		Unobservable input / assumptions		Range(1) (weighted average)
Impaired loans:
Commercial		$	311		Appraisal		Adjustments for comparable properties		9.0%-19.0% (14.4%)
Commercial real estate and multi-family		2,332			Appraisal		Adjustments for comparable properties		15.0% - 36.0% (22.0%)
Acquisition, development & construction		2,254			Appraisal		Adjustments for comparable properties		10.0% - 30.0% (13.5%)
Assets taken in foreclosure:
Commercial real estate and multi-family		3,619			Appraisal		Adjustments by management to reflect current conditions/selling costs		20.0% - 37.0% (24.8%)
Acquisition, development & construction		2,082			Appraisal		Adjustments by management to reflect current conditions/selling costs		25.0% - 70.0% (30.2%)
Residential mortgage		1,865			Appraisal		Adjustments by management to reflect current conditions/selling costs		16.0% - 59.0% (21.6%)
Mortgage servicing rights		1,863			Third-party valuation		Discount rate		9.3% - 12.8%
					Third-party valuation		Prepayment speed		100 - 968 (weighted average of 224)
(1) Represents range of discount factors applied to the appraisal to determine fair value. The amounts used for mortgage servicing rights are discounts applied by a third-party valuation provider which the Company believes are appropriate.
Fair Values of Financial Instruments
FASB Codification Topic 825 - Financial Instruments, requires disclosure of fair value information for those financial instruments for which it is practicable to estimate fair value, whether or not such financial instruments are recognized in the consolidated statements of financial condition for interim and annual periods. Fair value is the amount at which a financial instrument could be exchanged in a current transaction between willing parties, other than in a forced sale or liquidation.
Quoted market prices are used to estimate fair values when those prices are available, although active markets do not exist for many types of financial instruments. Fair values for these instruments must be estimated by management using techniques such as discounted cash flow analysis and comparison to similar instruments. These estimates are highly subjective and require judgments regarding significant matters, such as the amount and timing of future cash flows and the selection of discount rates that appropriately reflect market and credit risks. Changes in these judgments often have a material effect on the fair value estimates. Since these estimates are made as of a specific point in time, they are susceptible to material near-term changes. Fair values disclosed in accordance with FASB Topic 825 do not reflect any premium or discount that could result from the sale of a large volume of a particular financial instrument, nor do they reflect possible tax ramifications or estimated transaction costs.
The following is a summary of the carrying amounts and estimated fair values of financial assets and liabilities (none of which were held for trading purposes) as of December 31, 2013:
	December 31, 2013
	Carrying			Level 1 inputs				Level 2 inputs			Level 3 inputs
	amount
Financial assets:
Cash and due from banks	$	152,662		$	152,662			$	—		$	—
Securities available for sale	1,153,313			—				1,149,957			3,356
Securities held to maturity	486,902			—				479,977			—
Loans, net	4,096,529			—				—			4,150,709
Loans held for sale	24,483			—				24,483			—
Accrued interest receivable on securities	7,271			—				7,271			—
Accrued interest receivable on loans	8,785			—				—			8,785
FHLB stock and Federal Reserve Bank stock	43,326			—				—			—
Interest rate caps and swaps	621			—				621			—
Financial liabilities:
Non-maturity deposits	$	(4,270,379	)	$	(4,270,379	)		$	—		$	—
Certificates of deposit	(650,185		)	—				(650,061		)	—
FHLB and other borrowings	(489,787		)	—				(513,438		)	—
Other borrowings	(81,841		)	—				(82,106		)	—
Senior Notes	(98,123		)	—				(101,087		)	—
Subordinated debentures	(26,519		)	—				(26,338		)	—
Mortgage escrow funds	(13,460		)	—				(13,457		)	—
Accrued interest payable on deposits including escrow	(3,205		)	—				(3,205		)	—
Accrued interest payable on borrowings	(1,480		)	—				(1,480		)	—
Interest rate caps and swaps	(621		)	—				(621		)	—
The following is a summary of the carrying amounts and estimated fair values of financial assets and liabilities (none of which were held for trading purposes) as of September 30, 2013:
	September 30, 2013
	Carrying			Level 1 inputs				Level 2 inputs			Level 3 inputs
	amount
Financial assets:
Cash and due from banks	$	113,090		$	113,090			$	—		$	—
Securities available for sale	954,393			—				950,780			3,613
Securities held to maturity	253,999			—				250,896			—
Loans, net	2,384,021			—				—			2,422,824
Loans held for sale	1,011			—				1,011			—
Accrued interest receivable on securities	4,892			—				4,892			—
Accrued interest receivable on loans	6,805			—				—			6,805
FHLB stock	24,312			—				—			—
Interest rate caps and swaps	997			—				997			—
Financial liabilities:
Non-maturity deposits	(2,694,166		)	(2,694,166		)		—			—
Certificates of deposit	(268,128		)	—				(268,088		)	—
FHLB and other borrowings	(462,953		)	—				(488,369		)	—
Senior Notes	(98,033		)	—				(98,142		)	—
Mortgage escrow funds	(12,646		)	—				(12,644		)	—
Accrued interest payable on deposits including escrow	(1,480		)	—				(1,480		)	—
Accrued interest payable on borrowings	(1,525		)	—				(1,525		)	—
Interest rate caps and swaps	(997		)	—				(997		)	—
The following paragraphs summarize the principal methods and assumptions used by the Company to estimate the fair value of the Company’s financial instruments:
Loans
The estimated fair value approximates carrying value for variable-rate loans that reprice frequently and with no significant change in credit risk. The fair value of fixed-rate loans and variable-rate loans which reprice on an infrequent basis is estimated by discounting future cash flows using the current interest rates at which similar loans with similar terms would be made to borrowers of similar credit quality. An overall valuation adjustment is made for specific credit risks as well as general portfolio credit risk.
FHLB of New York Stock and Federal Reserve Bank Stock
The redeemable carrying amount of these securities with limited marketability approximates their fair value.
Deposits and Mortgage Escrow Funds
In accordance with FASB Codification Topic 825, deposits with no stated maturity (such as savings, demand and money market deposits) are assigned fair values equal to the carrying amounts payable on demand. Certificates of deposit and mortgage escrow funds are segregated by account type and original term, and fair values are estimated by discounting the contractual cash flows. The discount rate for each account grouping is equivalent to the current market rates for deposits of similar type and maturity.
These fair values do not include the value of core deposit relationships that comprise a significant portion of the Company’s deposits. We believe that the Company’s core deposit relationships provide a relatively stable, low-cost funding source that has a substantial value separate from the deposit balances.
Borrowings and Senior notes
The estimated fair value approximates carrying value for short-term borrowings. The fair value of long-term fixed-rate borrowings is estimated using quoted market prices, if available, or by discounting future cash flows using current interest rates for similar financial instruments.
Subordinated debentures
The fair value of subordinated debentures is estimated by discounting future cash flows using current interest rates for similar financial instruments.
Other Financial Instruments
Other financial assets and liabilities listed in the table below have estimated fair values that approximate the respective carrying amounts because the instruments are payable on demand or have short-term maturities and present relatively low credit risk and interest rate risk.
The fair values of the Company’s off-balance-sheet financial instruments described in Note 8. Guarantor’s Obligations Under Guarantees were estimated based on current market terms (including interest rates and fees), considering the remaining terms of the agreements and the credit worthiness of the counterparties. At December 31, 2013 and September 30, 2013, the estimated fair value of these instruments approximated the related carrying amounts, which were not material.
Accrued interest receivable/payable
The carrying amounts of accrued interest approximate fair value and are classified as Level 2.

Comprehensive_income_Comprehen

Comprehensive income Comprehensive Income	3 Months Ended
	Dec. 31, 2013
Comprehensive income [Abstract]	'
Comprehensive Income (Loss) Note [Text Block]	'
	Accumulated Other Comprehensive (Loss) Income
	Activity in accumulated other comprehensive (loss) income (“AOCI”), net of tax, for the three month periods ended December 31, 2013 and 2012, was as follows:
		Unrealized gains(losses) on securities				Unrealized gains (losses) for pension and other post-retirement obligations			Total
	Balance at September 30, 2012	$	15,066			$	(8,167	)	$	6,899
	Other comprehensive income before reclassifications	(1,678		)		285			(1,393		)
	Amounts reclassified from AOCI	(841		)		—			(841		)
	Period change	(2,519		)		285			(2,234		)
	Balance at December 31, 2012	$	12,547			$	(7,882	)	$	4,665
	Balance at September 30, 2013	$	(11,472	)		$	(3,858	)	$	(15,330	)
	Other comprehensive income before reclassifications	(6,013		)		—			(6,013		)
	Amounts reclassified from AOCI	431				1,447			1,878
	Period change	(5,582		)		1,447			(4,135		)
	Balance at December 31, 2013	$	(17,054	)		$	(2,411	)	$	(19,465	)
	The following table presents the reclassification adjustments from AOCI included in net income and the impacted line items on the income statement for the three months ended December 31, 2013:
	Components of AOCI		Amount reclassified from AOCI and impact on net income  (1)				Affected income statement line item
	Unrealized gains (losses) on available for sale securities
			$	(645	)		Non-interest income - net loss on sale of securities
			214				Tax benefit
			$	(431	)		Net change after tax
	Amortization of defined benefit pension items
	Loss on settlement of portion of defined benefit plan		$	(2,336	)		Non-interest expense - compensation and employee benefits (2)
			889				Tax benefit
			$	(1,447	)		Net change after tax
	(1) Amounts in parentheses indicate a reduction from income.
	(2) These accumulated other comprehensive (loss) income components are included in the computation of net periodic pension cost (see Note 13 - Pensions and Other Post Retirement Plans for additional details).

Recent_Accounting_Standards

Recent Accounting Standards	3 Months Ended
	Dec. 31, 2012
Recent accounting standards [Abstract]	'
New Accounting Pronouncements, Policy [Policy Text Block]	'
	Recently Issued Accounting Standards Not Yet Adopted
	Accounting Standards Update (“ASU”) 2014-04 - Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40) - Reclassification of Residential Real Estate Collateralized Consumer Mortgage loans upon Foreclosure was issued. This standard provides clarification when a creditor should be considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan such that the loan should be removed from the balance sheet and other real estate owned recognized. These amendments clarify that when an in-substance foreclosure occurs, and a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan upon either: (1) the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure, or (2) the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or through a similar legal agreement. This standard is effective for annual periods beginning after December 15, 2013 and is not expected to have a material impact on our balance sheet or results of operations.

Acquisition_Acquisition_Tables

Acquisition Acquisition (Tables)	3 Months Ended
	Dec. 31, 2013
Acquisition [Abstract]	'
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	'
	Consideration paid through Sterling Bancorp common stock issued to legacy Sterling shareholders				$	457,759
		Legacy Sterling carrying value				Fair value adjustments				As recorded at acquisition
	Cash and cash equivalents	$	277,798			$	—			$	277,798
	Investment securities	613,154				(5,189		)	(a)	607,965
	Loans held for sale	30,341				—				30,341
	Loans	1,704,801				(6,693		)	(b)	1,698,108
	Federal Reserve Bank stock	7,680				—				7,680
	Bank owned life insurance	55,374				—				55,374
	Premises and equipment	21,293				2,301			(c)	23,594
	Accrued interest receivable	6,590				—				6,590
	Core deposit and other intangibles	—				20,089			(d)	20,089
	Trade name intangible	—				20,500			(e)	20,500
	Other real estate owned	1,720				4,095			(f)	5,815
	Other assets	40,877				(18,611		)	(g)	22,266
	Deposits	(2,296,713		)		(477		)	(h)	(2,297,190		)
	FHLB borrowings	(100,346		)		(273		)	(i)	(100,619		)
	Other borrowings	(62,465		)		—				(62,465		)
	Subordinated debentures	(25,774		)		(753		)	(j)	(26,527		)
	Other liabilities	(60,462		)		4,502			(k)	(55,960		)
	Total identifiable net assets	$	213,868			$	19,491			$	233,359
	Goodwill recorded in the Merger									$	224,400
Purchased Credit Impaired Loans	'
	The acquired loan portfolio subject to purchased credit impairment accounting guidance (ASC 310-30) as of October 31, 2013 was comprised of collateral dependent loans with deteriorated credit quality as follows:
		ASC 310-30 loans
	Contractual principal balance at acquisition	$	24,176
	Principal not expected to be collected (non-accretable discount)	(10,927		)
	Expected cash flows at acquisition	13,249
	Interest component of expected cash flows (accretable discount)	—
	Fair value of acquired loans	$	13,249
Business Acquisition, Pro Forma Information	'
		Pro forma for the
		three months ended December 31,
		2013				2012
	Net interest income	$	53,188			$	55,011
	Non-interest income	16,174				16,796
	Non-interest expense	50,378				49,391
	Net income	11,480				11,028
	Pro forma earnings per share from continuing operations:
	Basic	$	0.14			$	0.13
	Diluted	0.14				0.13

Securities_Tables

Securities (Tables)	3 Months Ended
	Dec. 31, 2013
Marketable Securities [Abstract]	'
Summary of securities available for sale	'
	A summary of the amortized cost and estimated fair value of our securities is presented below:
		31-Dec-13												30-Sep-13
		Amortized			Gross			Gross			Fair value			Amortized		Gross			Gross			Fair value
		cost			unrealized			unrealized						cost		unrealized			unrealized
					gains			losses								gains			losses
	Available for Sale
	Residential mortgage-backed securities:
	Fannie Mae	$	236,701		$	557		$	(2,824	)	$	234,434		$	214,191	$	1,168		$	(3,921	)	$	211,438
	Freddie Mac	109,247			348			(859		)	108,736			67,272		593			(236		)	67,629
	Ginnie Mae	14,752			141			(67		)	14,826			3,374		88			—			3,462
	CMO/Other MBS	141,677			189			(2,601		)	139,265			169,336		356			(3,038		)	166,654
	Total residential mortgage-backed securities	502,377			1,235			(6,351		)	497,261			454,173		2,205			(7,195		)	449,183
	Other securities:
	Mutual funds	4,877			—			(23		)	4,854			—		—			—			—
	Federal agencies	264,082			32			(11,505		)	252,609			273,637		—			(12,090		)	261,547
	Corporate	202,225			84			(4,546		)	197,763			118,575		153			(3,795		)	114,933
	State and municipal	131,782			2,859			(1,547		)	133,094			127,324		3,447			(2,041		)	128,730
	Trust preferred	67,711			180			(159		)	67,732			—		—			—			—
	Total other securities	670,677			3,155			(17,780		)	656,052			519,536		3,600			(17,926		)	505,210
	Total available for sale	$	1,173,054		$	4,390		$	(24,131	)	$	1,153,313		$	973,709	$	5,805		$	(25,121	)	$	954,393
Held-to-maturity securities	'
		31-Dec-13												30-Sep-13
		Amortized			Gross			Gross			Fair value			Amortized		Gross			Gross			Fair value
		cost			unrecognized			unrecognized						cost		unrecognized			unrecognized
					gains			losses								gains			losses
	Held to Maturity
	Residential mortgage-backed securities:
	Fannie Mae	$	65,336		$	71		$	(692	)	$	64,715		$	70,502	$	399		$	(86	)	$	70,815
	Freddie Mac	27,040			47			—			27,087			59,869		317			(22		)	60,164
	CMO/Other MBS	71,329			11			(993		)	70,347			25,776		33			(315		)	25,494
	Total residential mortgage-backed securities	163,705			129			(1,685		)	162,149			156,147		749			(423		)	156,473
	Other securities:
	Federal agencies	133,994			—			(3,623		)	130,371			77,341		—			(3,458		)	73,883
	State and municipal	187,703			615			(2,375		)	185,943			19,011		556			(546		)	19,021
	Other	1,500			14			—			1,514			1,500		19			—			1,519
	Total other securities	323,197			629			(5,998		)	317,828			97,852		575			(4,004		)	94,423
	Total held to maturity	$	486,902		$	758		$	(7,683	)	$	479,977		$	253,999	$	1,324		$	(4,427	)	$	250,896
Investments Classified by Contractual Maturity Date [Table Text Block]	'
	The amortized cost and estimated fair values of securities at December 31, 2013 are presented below by contractual maturity. Actual maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations. Residential mortgage-backed securities are shown separately since they are not due at a single maturity date.
		December 31, 2013
		Available for sale						Held to maturity
		Amortized			Fair			Amortized			Fair
		cost			value			cost			value
	Remaining period to contractual maturity:
	One year or less	$	41,392		$	41,352		$	5,408		$	5,463
	One to five years	117,527			117,328			5,209			5,471
	Five to ten years	387,364			373,665			144,734			141,202
	Greater than ten years	124,394			123,707			167,846			165,692
	Total other securities	670,677			656,052			323,197			317,828
	Residential mortgage-backed securities	502,377			497,261			163,705			162,149
	Total securities	$	1,173,054		$	1,153,313		$	486,902		$	479,977
Sale of Securities [Table Text Block]	'
	Sales of securities for the three months ended December 31, 2013 and 2012 were as follows:
		For the three months ended December 31,
		2013			2012
	Available for sale securities:
	Proceeds from sales	$	247,650		$	41,965
	Gross realized gains	211			1,416
	Gross realized losses	(856		)	—
	Income tax benefit (expense) on realized gains	214			(575		)
Securities available for sale with unrealized losses	'
	The following table summarizes securities with unrealized losses, segregated by the length of time in a continuous unrealized loss position:
		Continuous unrealized loss position
		Less than 12 Months						12 months or longer						Total
		Fair			Unrealized			Fair			Unrealized			Fair		Unrealized
		value			losses			value			losses			value		losses
	Available for Sale
	31-Dec-13
	Residential mortgage-backed securities:
	Agency-backed	$	227,935		$	(3,750	)	$	—		$	—		$	227,935	$	(3,750	)
	CMO/Other MBS	114,362			(2,601		)	—			—			114,362		(2,601		)
	Total residential mortgage-backed securities	342,297			(6,351		)	—			—			342,297		(6,351		)
	Mutual fund	4,877			(23		)	—			—			4,877		(23		)
	Federal agencies	239,612			(11,351		)	4,846			(154		)	244,458		(11,505		)
	Corporate	171,851			(4,546		)	—			—			171,851		(4,546		)
	State and municipal	56,139			(1,511		)	936			(36		)	57,075		(1,547		)
	Trust preferred	47,634			(159		)	—			—			47,634		(159		)
	Total	$	862,410		$	(23,941	)	$	5,782		$	(190	)	$	868,192	$	(24,131	)
	30-Sep-13
	Residential mortgage-backed securities:
	Agency-backed	$	137,265		$	(4,157	)	$	—		$	—		$	137,265	$	(4,157	)
	CMO/Other MBS	122,324			(2,742		)	7,820			(296		)	130,144		(3,038		)
	Total residential mortgage-backed securities	259,589			(6,899		)	7,820			(296		)	267,409		(7,195		)
	Federal agencies	261,547			(12,090		)	—			—			261,547		(12,090		)
	Corporate	95,013			(3,795		)	—			—			95,013		(3,795		)
	State and municipal	43,585			(2,033		)	112			(8		)	43,697		(2,041		)
	Total	$	659,734		$	(24,817	)	$	7,932		$	(304	)	$	667,666	$	(25,121	)
Securities held to maturity with unrealized losses	'
		Continuous unrealized loss position
		Less than 12 Months						12 Months or longer						Total
		Fair			Unrealized			Fair			Unrealized			Fair		Unrealized
		value			losses			value			losses			value		losses
	Held to Maturity
	December 31, 2013
	Residential mortgage-backed securities:
	Agency-backed	$	50,558		$	(692	)	$	—		$	—		$	50,558	$	(692	)
	CMO/Other MBS	65,219			(993		)	—			—			65,219		(993		)
	Total residential mortgage-backed securities	115,777			(1,685		)	—			—			115,777		(1,685		)
	Federal agencies	132,089			(3,623		)	—			—			132,089		(3,623		)
	State and municipal	165,114			(2,375		)	—			—			165,114		(2,375		)
	Total	$	412,980		$	(7,683	)	$	—		$	—		$	412,980	$	(7,683	)
	30-Sep-13
	Residential mortgage-backed securities:
	Agency-backed	$	10,963		$	(86	)	$	—		$	—		$	10,963	$	(86	)
	CMO/Other MBS	31,412			(337		)	—			—			31,412		(337		)
	Total residential mortgage-backed securities	42,375			(423		)	—			—			42,375		(423		)
	Federal agencies	73,883			(3,458		)	—			—			73,883		(3,458		)
	State and municipal	9,530			(546		)	—			—			9,530		(546		)
	Total	$	125,788		$	(4,427	)	$	—		$	—		$	125,788	$	(4,427	)
Schedule of Financial Instruments Owned and Pledged as Collateral [Table Text Block]	'
	Securities pledged for borrowings at FHLB and other institutions, and securities pledged for municipal deposits and other purposes were as follows:
		December 31, 2013			September 30, 2013
	Available for sale securities pledged for borrowings, at fair value	$	810,290		$	199,642
	Available for sale securities pledged for municipal deposits, at fair value	63,573			580,756
	Held to maturity securities pledged for back-to-back swaps, at amortized cost	5,038			4,645
	Held to maturity securities pledged for borrowings, at amortized cost	101,981			55,497
	Held to maturity securities pledged for municipal deposits, at amortized cost	282,662			167,926
	Total securities pledged	$	1,263,544		$	1,008,466

Loans_Tables

Loans (Tables)	3 Months Ended
	Dec. 31, 2013
Loans [Abstract]	'
Components of loan portfolio excluding loans held for sale	'
	The composition of the Company’s loan portfolio, excluding loans held for sale, was the following:
		December 31, 2013				September 30, 2013
	Commercial:
	Commercial & industrial	$	1,025,222			$	439,787
	Payroll finance	122,961				—
	Warehouse lending	168,776				—
	Factored receivables	146,308				—
	Equipment financing	263,770				—
	Total commercial	1,727,037				439,787
	Commercial mortgage:
	Commercial real estate	1,262,362				969,490
	Multi-family	306,533				307,547
	Acquisition, development & construction	95,787				102,494
	Total commercial mortgage	1,664,682				1,379,531
	Total commercial and commercial mortgage	3,391,719				1,819,318
	Residential mortgage	527,425				400,009
	Consumer:
	Home equity lines of credit	154,102				156,995
	Other consumer loans	53,895				36,576
	Total consumer	207,997				193,571
	Total loans	4,127,141				2,412,898
	Allowance for loan losses	(30,612		)		(28,877		)
	Total loans, net	$	4,096,529			$	2,384,021
Troubled debt restructurings and other real estate owned	'
	The following tables set forth the amounts and status of the Company’s loans and troubled debt restructurings (“TDRs”) at December 31, 2013 and September 30, 2013:
		December 31, 2013
		Current				30-59				60-89			90+			Non-			Total
						days				days			days			accrual
						past due				past due			past due
	Commercial	$	1,670,399			$	22			$	54,560		$	91		$	1,965		$	1,727,037
	Commercial real estate & multi-family	1,547,358				3,816				990			—			16,731			1,568,895
	Acquisition, development & construction	91,035				311				86			273			4,082			95,787
	Residential mortgage	504,284				6,593				3,956			1,767			10,825			527,425
	Consumer	195,612				6,638				3,039			714			1,994			207,997
	Total loans	$	4,008,688			$	17,380			$	62,631		$	2,845		$	35,597		$	4,127,141
	Total TDRs included above	$	24,931			$	—			$	1,477		$	273		$	1,801		$	28,482
	Non-performing loans:
	Loans 90+ days past due and still accruing															$	2,845
	Non-accrual loans															35,597
	Total non-performing loans															$	38,442
		September 30, 2013
		Current				30-59				60-89			90+			Non-			Total
						days				days			days			accrual
						past due				past due			past due
	Commercial	$	438,818			$	178			$	2		$	289		$	500		$	439,787
	Commercial real estate & multi-family	1,263,933				1,978				2,357			1,574			7,195			1,277,037
	Acquisition, development & construction	96,306				768				—			—			5,420			102,494
	Residential mortgage	390,072				354				267			1,832			7,484			400,009
	Consumer	190,393				566				—			404			2,208			193,571
	Total loans	$	2,379,522			$	3,844			$	2,626		$	4,099		$	22,807		$	2,412,898
	Total TDRs included above	$	23,754			$	—			$	—		$	141		$	2,199		$	26,094
	Non-performing loans:
	Loans 90+ days past due and still accruing															$	4,099
	Non-accrual loans															22,807
	Total non-performing loans															$	26,906
Summary of activity in allowance for loan losses and recorded investments in loans by portfolio segment based on impairment method	'
	Activity in the allowance for loan losses for the three months ended December 31, 2013 and 2012 is summarized below:
		For the three months ended December 31, 2013
		Beginning				Charge-offs				Recoveries			Net			Provision			Ending balance
		balance											charge-offs
	Commercial	$	5,302			$	(528	)		$	501		$	(27	)	$	1,611		$	6,886
	Commercial real estate & multi-family	9,967				(671		)		37			(634		)	659			9,992
	Acquisition, development & construction	5,806				(218		)		—			(218		)	269			5,857
	Residential mortgage	4,474				(270		)		7			(263		)	389			4,600
	Consumer	3,328				(147		)		24			(123		)	72			3,277
	Total loans	$	28,877			$	(1,834	)		$	569		$	(1,265	)	$	3,000		$	30,612
	Annualized net charge-offs to average loans outstanding																		0.14		%
		For the three months ended December 31, 2012
		Beginning				Charge-offs				Recoveries			Net			Provision			Ending balance
		balance											charge-offs
	Commercial	$	4,603			$	(159	)		$	120		$	(39	)	$	969		$	5,533
	Commercial real estate & multi-family	7,230				(228		)		81			(147		)	533			7,616
	Acquisition, development & construction	8,526				(1,594		)		5			(1,589		)	89			7,026
	Residential mortgage	4,359				(950		)		51			(899		)	908			4,368
	Consumer	3,564				(483		)		39			(444		)	451			3,571
	Total loans	$	28,282			$	(3,414	)		$	296		$	(3,118	)	$	2,950		$	28,114
	Annualized net charge-offs to average loans outstanding																		0.58		%
	Management considers a loan to be impaired when, based on current information and events, it is determined that the Company will not be able to collect all amounts due according to the loan contract, including scheduled interest payments. Determination of impairment is treated the same across all classes of loans on a loan-by-loan basis, except residential mortgage loans and home equity lines of credit with an outstanding balance of $500 or less which are evaluated for impairment on a homogeneous pool basis. When management identifies a loan as impaired, the impairment is measured based on the present value of expected future cash flows, discounted at the loan’s effective interest rate, except when the sole remaining source of repayment of the loan is the operation or liquidation of the collateral. In these cases management uses the current fair value of the collateral, less selling costs when foreclosure is probable, instead of discounted cash flows. If management determines that the value of the impaired loan is less than the recorded investment in the loan (net of previous charge-offs, deferred loan fees or costs and unamortized premium or discount), impairment is generally recognized through a charge-off to the allowance for loan losses.
	When the ultimate collectibility of the total principal of an impaired loan is in doubt and the loan is on non-accrual status, all payments are applied to principal, under the cost recovery method. When the ultimate collectibility of the total principal of an impaired loan is not in doubt and the loan is on non-accrual status, contractual interest is credited to interest income when received, under the cash basis method.
Loans Evaluated For Impairment By Segment	'
	The following table presents loans individually evaluated for impairment by segment of loans at December 31, 2013 and September 30, 2013:
		31-Dec-13											30-Sep-13
		Unpaid				Recorded				Related allowance			Unpaid			Recorded			Related allowance
		principal				investment							principal			investment
		balance											balance
	With no related allowance recorded:
	Commercial	$	7,379			$	4,597			$	—		$	2,175		$	2,131		$	—
	Commercial real estate & multi-family	28,027				21,879				—			12,451			11,820			—
	Acquisition, development & construction	16,152				16,115				—			17,971			17,945			—
	Residential mortgage	4,217				4,135				—			515			515			—
	Consumer	—				—				—			—			—			—
	Subtotal	55,775				46,726				—			33,112			32,411			—
	With an allowance recorded:
	Commercial	312				312				162			500			500			249
	Commercial real estate & multi-family	—				—				—			3,150			2,271			803
	Acquisition, development & construction	2,813				1,813				524			2,753			1,637			540
	Consumer	—				—				—			2			2			1
	Subtotal	3,125				2,125				686			6,405			4,410			1,593
	Total	$	58,900			$	48,851			$	686		$	39,517		$	36,821		$	1,593
	The following table presents the average recorded investment and interest income recognized related to loans individually evaluated for impairment by segment for the three months ended December 31, 2013 and 2012:
		31-Dec-13											31-Dec-12
		QTD				Interest				Cash-basis			QTD			Interest			Cash-basis
		average				income				interest			average			income			interest
		recorded				recognized				income			recorded			recognized			income
		investment								recognized			investment						recognized
	With no related allowance recorded:
	Commercial	$	3,759			$	20			$	2		$	225		$	2		$	—
	Commercial real estate & multi-family	19,318				52				—			12,458			58			54
	Acquisition, development & construction	17,108				148				—			13,760			87			48
	Residential mortgage	4,890				—				—			7,237			43			31
	Consumer	—				—				—			2,477			8			1
	Subtotal	45,075				220				2			36,157			198			134
	With an allowance recorded:
	Commercial	314				—				—			2,410			21			6
	Commercial real estate & multi-family	—				—				—			5,025			14			—
	Residential mortgage	—				—				—			5,484			17			18
	Acquisition, development & construction	1,932				—				—			2,919			40			—
	Consumer	—				—				—			784			—			—
	Subtotal	2,246				—				—			16,622			92			24
	Total	$	47,321			$	220			$	2		$	52,779		$	290		$	158
Loans and allowance evaluated for impairment by segment	'
	The following table sets forth loans evaluated for impairment by segment and the allowance evaluated by segment at December 31, 2013:
		Loans evaluated by segment														Allowance evaluated by segment
		Individually				Collectively				Purchased credit impaired loans			Total			Individually			Collectively			Total allowance for loan losses
		evaluated for				evaluated for							loans			evaluated for			evaluated for
		impairment				impairment										impairment			impairment
	Commercial	$	2,272			$	1,722,128			$	2,637		$	1,727,037		$	162		$	6,724		$	6,886
	Commercial real estate & multi-family	13,482				1,547,016				8,397			1,568,895			—			9,992			9,992
	Acquisition, development & construction	17,928				77,859				—			95,787			524			5,333			5,857
	Residential mortgage	515				523,290				3,620			527,425			—			4,600			4,600
	Consumer	—				207,997				—			207,997			—			3,277			3,277
	Total loans	$	34,197			$	4,078,290			$	14,654		$	4,127,141		$	686		$	29,926		$	30,612
	There was no amount included in the allowance for loan losses associated with purchased credit impaired loans at December 31, 2013, as there was no further deterioration in the credit quality of these loans since the Merger date.
	The following table sets forth the loans evaluated for impairment by segment and the allowance evaluated by segment at September 30, 2013:
		Loans evaluated by segment											Allowance evaluated by segment
		Individually				Collectively				Total			Individually			Collectively			Total allowance for loan losses
		evaluated for				evaluated for				loans			evaluated for			evaluated for
		impairment				impairment							impairment			impairment
	Commercial	$	2,631			$	437,156			$	439,787		$	249		$	5,053		$	5,302
	Commercial real estate & multi-family	14,091				1,262,946				1,277,037			803			9,164			9,967
	Acquisition, development & construction	19,582				82,912				102,494			540			5,266			5,806
	Residential mortgage	515				399,494				400,009			—			4,474			4,474
	Consumer	2				193,569				193,571			1			3,327			3,328
	Total loans	$	36,821			$	2,376,077			$	2,412,898		$	1,593		$	27,284		$	28,877
Troubled debt restructurings	'
	The following tables set forth the amounts of the Company’s TDRs at December 31, 2013 and September 30, 2013:
		31-Dec-13
		Current loans				30-59				60-89			90+			Non-			Total
						days				days			days			accrual
						past due				past due			past due
	Commercial	$	1,825			$	—			$	—		$	—		$	136		$	1,961
	Commercial real estate & multi-family	5,301				—				—			—			62			5,363
	Acquisition, development & construction	13,625				—				—			273			138			14,036
	Residential mortgage	4,180				—				1,477			—			1,465			7,122
	Total	$	24,931			$	—			$	1,477		$	273		$	1,801		$	28,482
	Allowance for loan losses	$	759			$	—			$	—		$	16		$	—		$	775
		30-Sep-13
		Current loans				30-59				60-89			90+			Non-			Total
						days				days			days			accrual
						past due				past due			past due
	Commercial	$	1,843			$	—			$	—		$	141		$	—		$	1,984
	Commercial real estate & multi-family	5,305				—				—			—			—			5,305
	Acquisition, development & construction	14,190				—				—			—			151			14,341
	Residential mortgage	2,416				—				—			—			1,792			4,208
	Consumer	—				—				—			—			256			256
	Total	$	23,754			$	—			$	—		$	141		$	2,199		$	26,094
	Allowance for loan losses	$	438			$	—			$	—		$	—		$	439		$	877
	The following table presents loans by segment modified as TDRs that occurred during the three months ended December 31, 2013 and 2012:
		December 31, 2013										31-Dec-12
					Recorded investment									Recorded investment
		Number			Pre-				Post-			Number		Pre-			Post-
					modification				modification					modification			modification
	Commercial	—			$	—			$	—		1		$	1,500		$	1,500
	Commercial & multi-family	—			—				—			1		450			450
	Acquisition, development & construction	—			—				—			2		2,723			2,723
	Residential mortgage	—			—				—			1		275			275
	Total restructured loans	—			$	—			$	—		5		$	4,948		$	4,948
Risk category of loans by segment of gross loans	'
		December 31, 2013											September 30, 2013
		Special				Substandard				Doubtful			Special			Substandard			Doubtful
		mention											mention
	Commercial & industrial	$	20,822			$	7,644			$	312		$	3,545		$	3,855		$	365
	Payroll finance	—				476				—			—			—			—
	Factored receivables	3,262				—				—			—			—			—
	Equipment financing	—				65				—			—			—			—
	Commercial real estate & multi-family	7,448				30,132				—			7,279			24,561			227
	Acquisition, development & construction	524				19,336				—			1,867			19,410			—
	Residential mortgage	3,290				14,841				—			824			9,786			—
	Consumer	3,488				4,531				—			15			2,891			—
	Total	$	38,834			$	77,025			$	312		$	13,530		$	60,503		$	592

Deposits_Tables

Deposits (Tables)	3 Months Ended
	Dec. 31, 2013
Deposits [Abstract]	'
Summary of major classification of deposits	'
	Deposit balances are summarized as follows:
		December 31,		September 30,
		2013		2013
	Non-interest bearing demand	$	1,575,174	$	943,934
	Interest bearing demand	775,618		434,398
	Savings	605,168		580,125
	Money market	1,314,419		735,709
	Certificates of deposit	650,185		268,128
	Total deposits	$	4,920,564	$	2,962,294
List of Company's Brokered deposits	'
	Summarized below are the Company’s brokered deposits included in the table above:
		December 31,		September 30,
		2013		2013
	Money market	$	59,069	$	34,571
	Reciprocal CDARs(1)	25,331		1,343
	CDARs one way	8,274		768
	Total brokered deposits	$	92,674	$	36,682
	(1)  Certificate of deposit account registry service.

Borrowings_Tables

Borrowings (Tables)	3 Months Ended
	Dec. 31, 2013
Debt Instruments [Abstract]	'
Schedule of debt	'
	The Company’s FHLB and other borrowings and weighted average interest rates are summarized below:
		December 31, 2013				September 30, 2013
		Amount		Rate		Amount		Rate
	By type of borrowing:
	FHLB borrowings	$	489,787	2.29	%	$	442,602	2.77	%
	Commercial paper	20,658		0.31		—		—
	Repurchase agreements	61,183		0.87		20,351		0.88
	Senior Notes	98,123		5.98		98,033		5.98
	Total borrowings	$	669,751	2.64	%	$	560,986	3.26	%
	By remaining period to maturity:
	One year or less	$	119,573	0.63	%	$	158,897	0.95	%
	One to two years	96,511		0.85		78,717		1.97
	Two to three years	132,863		0.7		191		5.32
	Three to four years	200,000		4.23		202,414		4.21
	Four to five years	118,124		5.57		118,033		5.57
	Greater than five years	2,680		4.92		2,734		4.92
	Total borrowings	$	669,751	2.64	%	$	560,986	3.26	%

Subordinated_Debentures_Subord1

Subordinated Debentures Subordinated Debentures (Tables)	3 Months Ended
	Dec. 31, 2013
Subordinated Debentures [Abstract]	'
Schedule of Subordinated Borrowing [Table Text Block]	'
		31-Dec-13		30-Sep-13
	Subordinated debentures	$	25,774	$	—
	Premium recorded to reflect fair value at acquisition date	745		—
		$	26,519	$	—

Earnings_Per_Common_Share_Tabl

Earnings Per Common Share (Tables)	3 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Computation of basic and diluted earnings per share	'
	Basic earnings per common share are computed as follows:
		For the three months ended December 31,
		2013			2012
	Weighted average common shares outstanding (basic)	70,493,305			43,637,315
	Net (loss) income	$	(14,002	)	$	7,020
	Basic (loss) earnings per common share	(0.20		)	0.16
	Diluted earnings per common share are computed as follows:
		For the three months ended December 31,
		2013			2012
	Weighted average common shares outstanding (basic)	70,493,305			43,637,315
	Effect of common stock equivalents	—			83,776
	Weighted average common shares outstanding (diluted)	70,493,305			43,721,091
	Net (loss) income	$	(14,002	)	$	7,020
	Diluted (loss) earnings per common share	(0.20		)	0.16

Other_Noninterest_expense_Othe1

Other Non-interest expense Other Non-interest expense (Tables)	3 Months Ended
	Dec. 31, 2013
Other Non-Interest Expense [Abstract]	'
Other non- interest expense [Table Text Block]	'
		December 31,
		2013		2012
	Other non-interest expense:
	Advertising and promotion	$	309	$	244
	Professional fees	1,818		1,215
	Data and check processing	595		649
	Other	4,733		2,565
	Total other non-interest expense	$	7,455	$	4,673

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	3 Months Ended
	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Fair value of options granted determined using weighted-average assumptions as grant date	'
	The fair value of options granted was determined using the following weighted average assumptions as of the grant date:
		For the three months ended December 31,
		2013		2012
	Risk-free interest rate	1.74	%	0.96	%
	Expected stock price volatility	26.5	%	40.8	%
	Dividend yield (1)	2.05	%	2.61	%
	Expected term in years	5.75		5.75
	(1) Represents the approximate annualized cash dividend rate paid with respect to a share of common stock at or near the grant date.
Summary of Company's stock option activity	'
	The following table summarizes the combined activity in the Company’s stock-based compensation plans for the three months ended December 31, 2013:
				Non-vested stock awards/stock units outstanding				Stock options outstanding
		Shares available for grant		Number of shares		Weighted average grant date fair value		Number of shares		Weighted average exercise price
	Balance at September 30, 2013	2,066,184		209,697		$	8.73	2,114,509		$	10.71
	Grants associated with legacy Sterling Merger(1)	(921,503	)	351,964		11.72		104,152		14.25
	Granted (1)	(595,435	)	101,078		11.36		249,862		11.36
	Stock awards vested	—		(44,523	)	8.73		—		—
	Exercised	—		—		—		(338,177	)	12.16
	Forfeited	36,656		—		—		(36,656	)	8.59
	Balance at December 31, 2013	585,902		618,216		$	10.83	2,093,690		$	10.77
	Exercisable at December 31, 2013							1,293,662		$	11.64
	(1) Reflects certain non-vested stock awards that count as 3.6 shares deducted from the plan for every one share delivered under these awards.

Pension_and_Other_Post_Retirem1

Pension and Other Post Retirement Plans (Tables)	3 Months Ended
	Dec. 31, 2013
Compensation Related Costs [Abstract]	'
Net post-retirement cost, recorded within salaries and employee benefits expense	'
	Net pension and post-retirement expense, which is recorded in compensation and employee benefits expense in the consolidated statements of operations, is comprised of the following:
		Pension plan						Other post
								retirement plans
		For the three months ended December 31,						For the three months ended December 31,
		2013			2012			2013		2012
	Service cost	$	—		$	—		$	12	$	11
	Interest cost	402			363			34		31
	Expected return on plan assets	(672		)	(616		)	—		—
	Amortization of net transition obligation	—			—			6		6
	Amortization of prior service cost	—			—			12		12
	Amortization of (gain) or loss	97			516			—		(6		)
	Charge for settlement of a portion of defined benefit plan	2,743			—			—		—
	Total cost	$	2,570		$	263		$	64	$	54

Derivatives_Tables

Derivatives (Tables)	3 Months Ended
	Dec. 31, 2013
Derivative Instruments and Hedges, Assets [Abstract]	'
Summary of derivatives	'
	Summary information regarding these derivatives is presented below:
		Notional			Average	Weighted		Weighted average	Fair value
		amount			maturity (in years)	average		variable rate
						fixed rate
	At December 31, 2013
	Interest rate caps	$	50,000		0.92	3.75	%	NA	$	—
	Third-party interest rate swaps	53,666			5.51	4.22		1 m Libor + 2.45	621
	Customer interest rate swaps	(53,666		)	5.51	4.22		1 m Libor + 2.45	(621		)
	At September 30, 2013
	Interest rate caps	$	50,000		1.18	3.75	%	NA	$	—
	Third-party interest rate swaps	54,180			5.76	4.22		1 m Libor + 2.45	997
	Customer interest rate swaps	(54,180		)	5.76	4.22		1 m Libor + 2.45	(997		)

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Investment grades of securities	'
	The credit ratings of private label CMO securities at December 31, 2013 were as follows:
		Amortized			Fair
		cost			value
	Credit rating:
	Baa1	$	187		$	188
	Ba1	100			95
	B1	1,790			1,786
	B3	1,285			1,287
	Total private label CMOs	$	3,362		$	3,356
Estimated fair value on a recurring basis	'
	A summary of assets and liabilities at December 31, 2013 measured at estimated fair value on a recurring basis is as follows:
		December 31, 2013
		Fair value			Level 1 inputs				Level 2 inputs			Level 3 inputs
	Assets:
	Investment securities available for sale:
	Residential mortgage-backed securities:
	Fannie Mae	$	234,434		$	—			$	234,434		$	—
	Freddie Mac	108,736			—				108,736			—
	Ginnie Mae	14,826			—				14,826			—
	CMO/Other MBS	135,909			—				135,909			—
	Private label CMOs	3,356			—				—			3,356
	Total residential mortgage-backed securities	497,261			—				493,905			3,356
	Other securities:
	US Government	4,854			—				4,854			—
	Federal agencies	252,609			—				252,609			—
	Corporate bonds	197,763			—				197,763			—
	State and municipal	133,094			—				133,094			—
	Trust preferred securities	67,732			—				67,732			—
	Total other securities	656,052			—				656,052			—
	Total investment securities available for sale	1,153,313			—				1,149,957			3,356
	Interest rate caps and swaps	621			—				621			—
	Total assets measured at estimated fair value on a recurring basis	$	1,153,934		$	—			$	1,150,578		$	3,356
	Liabilities:
	Interest rate swaps	$	621		$	—			$	621		$	—
	Total liabilities measured at estimated fair value on a recurring basis	$	621		$	—			$	621		$	—
	A summary of assets and liabilities at September 30, 2013 measured at estimated fair value on a recurring basis is as follows:
		September 30, 2013
		Fair value			Level 1 inputs				Level 2 inputs			Level 3 inputs
	Assets:
	Investment securities available for sale:
	Residential mortgage-backed securities:
	Fannie Mae	$	211,438		$	—			$	211,438		$	—
	Freddie Mac	67,629			—				67,629			—
	Ginnie Mae	3,462			—				3,462			—
	CMO/Other MBS	163,041			—				163,041			—
	Private label CMOs	3,613			—				—			3,613
	Total residential mortgage-backed securities	449,183			—				445,570			3,613
	Other securities:
	Federal agencies	261,547			—				261,547			—
	Corporate debt securities	114,933			—				114,933			—
	State and municipal	128,730			—				128,730			—
	Total other securities	505,210			—				505,210			—
	Total investment securities available for sale	954,393			—				950,780			3,613
	Interest rate caps and swaps	997			—				997			—
	Total assets measured at estimated fair value on a recurring basis	$	955,390		$	—			$	951,777		$	3,613
	Liabilities:
	Interest rate swaps	$	997		$	—			$	997		$	—
	Total liabilities measured at estimated fair value on a recurring basis	$	997		$	—			$	997		$	—
Changes in Level 3 assets measured at fair value on recurring basis	'
		Changes in Level 3 assets for the three months ended December 31, 2013			Changes in Level 3 assets for the three months ended December 31, 2012
	Balance at September 30,	$	3,613		$	4,630
	Paydowns	(275		)	(325		)
	Amortization, net	—			6
	OTTI	—			(14		)
	Change in fair value	18			63
	Balance at December 31,	$	3,356		$	4,360
Impaired loans measured at estimated fair value on nonrecurring basis	'
	December 31, 2013 measured at estimated fair value on a non-recurring basis is the following:
		December 31, 2013
		Fair value			Level 1 inputs				Level 2 inputs			Level 3 inputs
	Commercial	$	311		$	—			$	—		$	311
	Commercial real estate and multi-family	2,332			—				—			2,332
	Acquisition, development & construction	2,254			—				—			2,254
	Total impaired loans measured at fair value	$	4,897		$	—			$	—		$	4,897
	A summary of impaired loans at September 30, 2013 measured at estimated fair value on a non-recurring basis is the following:
		September 30, 2013
		Fair value			Level 1 inputs				Level 2 inputs			Level 3 inputs
	Commercial	$	500		$	—			$	—		$	500
	Commercial real estate and multi-family	3,672			—				—			3,672
	Acquisition, development & construction	1,839			—				—			1,839
	Consumer loans	2			—				—			2
	Total impaired loans measured at fair value	$	6,013		$	—			$	—		$	6,013
Quantitative information of Level 3 assets	'
	December 31, 2013:
	Non-recurring fair value measurements		Fair value			Valuation technique		Unobservable input / assumptions		Range(1) (weighted average)
	Impaired loans:
	Commercial		$	311		Appraisal		Adjustments for comparable properties		9.0%-19.0% (14.4%)
	Commercial real estate and multi-family		2,332			Appraisal		Adjustments for comparable properties		15.0% - 36.0% (22.0%)
	Acquisition, development & construction		2,254			Appraisal		Adjustments for comparable properties		10.0% - 30.0% (13.5%)
	Assets taken in foreclosure:
	Commercial real estate and multi-family		3,619			Appraisal		Adjustments by management to reflect current conditions/selling costs		20.0% - 37.0% (24.8%)
	Acquisition, development & construction		2,082			Appraisal		Adjustments by management to reflect current conditions/selling costs		25.0% - 70.0% (30.2%)
	Residential mortgage		1,865			Appraisal		Adjustments by management to reflect current conditions/selling costs		16.0% - 59.0% (21.6%)
	Mortgage servicing rights		1,863			Third-party valuation		Discount rate		9.3% - 12.8%
						Third-party valuation		Prepayment speed		100 - 968 (weighted average of 224)
Summary of carrying amounts and estimated fair values of financial assets and liabilities	'
	The following is a summary of the carrying amounts and estimated fair values of financial assets and liabilities (none of which were held for trading purposes) as of September 30, 2013:
		September 30, 2013
		Carrying			Level 1 inputs				Level 2 inputs			Level 3 inputs
		amount
	Financial assets:
	Cash and due from banks	$	113,090		$	113,090			$	—		$	—
	Securities available for sale	954,393			—				950,780			3,613
	Securities held to maturity	253,999			—				250,896			—
	Loans, net	2,384,021			—				—			2,422,824
	Loans held for sale	1,011			—				1,011			—
	Accrued interest receivable on securities	4,892			—				4,892			—
	Accrued interest receivable on loans	6,805			—				—			6,805
	FHLB stock	24,312			—				—			—
	Interest rate caps and swaps	997			—				997			—
	Financial liabilities:
	Non-maturity deposits	(2,694,166		)	(2,694,166		)		—			—
	Certificates of deposit	(268,128		)	—				(268,088		)	—
	FHLB and other borrowings	(462,953		)	—				(488,369		)	—
	Senior Notes	(98,033		)	—				(98,142		)	—
	Mortgage escrow funds	(12,646		)	—				(12,644		)	—
	Accrued interest payable on deposits including escrow	(1,480		)	—				(1,480		)	—
	Accrued interest payable on borrowings	(1,525		)	—				(1,525		)	—
	Interest rate caps and swaps	(997		)	—				(997		)	—
	The following is a summary of the carrying amounts and estimated fair values of financial assets and liabilities (none of which were held for trading purposes) as of December 31, 2013:
		December 31, 2013
		Carrying			Level 1 inputs				Level 2 inputs			Level 3 inputs
		amount
	Financial assets:
	Cash and due from banks	$	152,662		$	152,662			$	—		$	—
	Securities available for sale	1,153,313			—				1,149,957			3,356
	Securities held to maturity	486,902			—				479,977			—
	Loans, net	4,096,529			—				—			4,150,709
	Loans held for sale	24,483			—				24,483			—
	Accrued interest receivable on securities	7,271			—				7,271			—
	Accrued interest receivable on loans	8,785			—				—			8,785
	FHLB stock and Federal Reserve Bank stock	43,326			—				—			—
	Interest rate caps and swaps	621			—				621			—
	Financial liabilities:
	Non-maturity deposits	$	(4,270,379	)	$	(4,270,379	)		$	—		$	—
	Certificates of deposit	(650,185		)	—				(650,061		)	—
	FHLB and other borrowings	(489,787		)	—				(513,438		)	—
	Other borrowings	(81,841		)	—				(82,106		)	—
	Senior Notes	(98,123		)	—				(101,087		)	—
	Subordinated debentures	(26,519		)	—				(26,338		)	—
	Mortgage escrow funds	(13,460		)	—				(13,457		)	—
	Accrued interest payable on deposits including escrow	(3,205		)	—				(3,205		)	—
	Accrued interest payable on borrowings	(1,480		)	—				(1,480		)	—
	Interest rate caps and swaps	(621		)	—				(621		)	—

Comprehensive_Income_Tables

Comprehensive Income (Tables)	3 Months Ended
	Dec. 31, 2013
Comprehensive income [Abstract]	'
Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block]	'
	Activity in accumulated other comprehensive (loss) income (“AOCI”), net of tax, for the three month periods ended December 31, 2013 and 2012, was as follows:
		Unrealized gains(losses) on securities				Unrealized gains (losses) for pension and other post-retirement obligations			Total
	Balance at September 30, 2012	$	15,066			$	(8,167	)	$	6,899
	Other comprehensive income before reclassifications	(1,678		)		285			(1,393		)
	Amounts reclassified from AOCI	(841		)		—			(841		)
	Period change	(2,519		)		285			(2,234		)
	Balance at December 31, 2012	$	12,547			$	(7,882	)	$	4,665
	Balance at September 30, 2013	$	(11,472	)		$	(3,858	)	$	(15,330	)
	Other comprehensive income before reclassifications	(6,013		)		—			(6,013		)
	Amounts reclassified from AOCI	431				1,447			1,878
	Period change	(5,582		)		1,447			(4,135		)
	Balance at December 31, 2013	$	(17,054	)		$	(2,411	)	$	(19,465	)
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	'
	eclassification adjustments from AOCI included in net income and the impacted line items on the income statement for the three months ended December 31, 2013:
	Components of AOCI		Amount reclassified from AOCI and impact on net income  (1)				Affected income statement line item
	Unrealized gains (losses) on available for sale securities
			$	(645	)		Non-interest income - net loss on sale of securities
			214				Tax benefit
			$	(431	)		Net change after tax
	Amortization of defined benefit pension items
	Loss on settlement of portion of defined benefit plan		$	(2,336	)		Non-interest expense - compensation and employee benefits (2)
			889				Tax benefit
			$	(1,447	)		Net change after tax
	(1) Amounts in parentheses indicate a reduction from income.
	(2) These accumulated other comprehensive (loss) income components are included in the computation of net periodic pension cost (see Note 13 - Pensions and Other Post Retirement Plans for additional details).

Acquisition_Acquisition_Detail

Acquisition Acquisition (Details) (USD $)

3 Months Ended

0 Months Ended

3 Months Ended

Dec. 31, 2013

Sep. 30, 2013

Oct. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Oct. 31, 2013

Oct. 31, 2013

Oct. 31, 2013

Oct. 31, 2013

Oct. 31, 2013

Oct. 31, 2013

Oct. 31, 2013

Oct. 31, 2013

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Assets Write-down, Retention, and Severance Costs [Member]

Equipment [Member]

Equipment [Member]

Core deposits and other intangibles

Core deposits and other intangibles

Trade name intangible

Book Value [Member]

Book Value [Member]

Book Value [Member]

Fair Value Adjustment [Member]

Fair Value Adjustment [Member]

Fair Value Adjustment [Member]

Minimum [Member]

Maximum [Member]

Core deposits and other intangibles

Trade name intangible

Core deposits and other intangibles

Trade name intangible

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Acquired Finite-lived Intangible Assets, Weighted Average Useful Life

'

'

'

'

'

'

'

'

'10 years

'

'

'

'

'

'

'

'

Property, Plant and Equipment, Useful Life

'

'

'

'

'

'

'1 year

'5 years

'

'

'

'

'

'

'

'

'

Number of shares received by legacy Sterling for each share of their stock

'

'

1.2625

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of shares issued

'

'

39,057,968

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Closing price

'

'

$11.72

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Consideration paid

$457,759,000

'

$457,759,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

legacy Sterling assets

'

'

2,800,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Federal Home Loan Bank Stock

'

'

1,700,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Major Class of Assets Acquired and Liabilities Assumed

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash and cash equivalents

'

'

277,798,000

'

'

'

'

'

'

'

'

277,798,000

'

'

0

'

'

Investment securities

'

'

607,965,000

'

'

'

'

'

'

'

'

613,154,000

'

'

-5,189,000

[1]

'

'

Loans held for sale

'

'

30,341,000

'

'

'

'

'

'

'

'

30,341,000

'

'

0

'

'

Loans

'

'

1,698,108,000

'

'

'

'

'

'

'

'

1,704,801,000

'

'

-6,693,000

[2]

'

'

Federal Reserve Bank stock

'

'

7,680,000

'

'

'

'

'

'

'

'

7,680,000

'

'

0

'

'

Bank owned life insurance

'

'

55,374,000

'

'

'

'

'

'

'

'

55,374,000

'

'

0

'

'

Premises and equipment

'

'

23,594,000

'

'

'

'

'

'

'

'

21,293,000

'

'

2,301,000

[3]

'

'

Accrued interest receivable

'

'

6,590,000

'

'

'

'

'

'

'

'

6,590,000

'

'

0

'

'

Intangibles

'

'

20,089,000

'

'

'

'

'

'

20,089,000

20,500,000

'

0

0

'

20,089,000

[4]

20,500,000

[5]

Other real estate owned

'

'

5,815,000

'

'

'

'

'

'

'

'

1,720,000

'

'

4,095,000

[6]

'

'

Other assets

'

'

22,266,000

'

'

'

'

'

'

'

'

40,877,000

'

'

-18,611,000

[7]

'

'

Deposits

'

'

-2,297,190,000

'

'

'

'

'

'

'

'

-2,296,713,000

'

'

-477,000

[8]

'

'

FHLB borrowings

'

'

-100,619,000

'

'

'

'

'

'

'

'

-100,346,000

'

'

-273,000

[9]

'

'

Other borrowings

'

'

-62,465,000

'

'

'

'

'

'

'

'

-62,465,000

'

'

0

'

'

Subordinated debentures

'

'

-26,527,000

'

'

'

'

'

'

'

'

-25,774,000

'

'

-753,000

[10]

'

'

Other liabilities

'

'

-55,960,000

'

'

'

'

'

'

'

'

-60,462,000

'

'

4,502,000

[11]

'

'

Total identifiable net assets

'

'

233,359,000

'

'

'

'

'

'

'

'

213,868,000

'

'

19,491,000

'

'

Goodwill

387,517,000

163,117,000

224,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Direct merger, acquisition and integration costs expensed

'

'

'

9,100,000

0

'

'

'

'

'

'

'

'

'

'

'

'

Other integration costs expensed

'

'

'

'

'

$22,200,000

'

'

'

'

'

'

'

'

'

'

'

[1]

Represents the fair value adjustment on investment securities held to maturity.

[2]

Represents the elimination of legacy Sterling’s allowance for loan losses and an adjustment of the amortized cost of loans to estimated fair value, which includes an interest rate mark and credit mark.

[3]

Represents an adjustment to reflect the fair value of leasehold improvements.

[4]

Represents intangible assets recorded to reflect the fair value of core deposits and below market rent on leased premises. The core deposit asset was recorded as an identifiable intangible asset and will be amortized on an accelerated basis over the estimated average life of the deposit base. The below market rent intangible asset will be amortized on a straight-line basis over the remaining term of the leases.

[5]

Represents the estimated fair value of Sterling Bancorp’s trade name. This intangible asset will not be amortized and will be reviewed at least annually for impairment.

[6]

Represents an adjustment to an acquired property which legacy Sterling utilized as a financial center and recorded as premises and equipment. As the Company intends to sell this asset, it was recorded in other real estate owned at estimated fair value determined using an independent appraisal.

[7]

Consists primarily of adjustments in net deferred tax assets resulting from the fair value adjustments related to the acquired assets, liabilities assumed and identifiable intangibles recorded.

[8]

Represents the fair value adjustment on deposits as the weighted average interest rate of deposits assumed exceeded the cost of similar funding available in the market at the time of the Merger.

[9]

Represents the fair value adjustment on FHLB borrowings as the weighted average interest rate of FHLB borrowings assumed exceeded the cost of similar funding available in the market at the time of the Merger.

[10]

Represents the fair value adjustment on subordinated debentures as the weighted average interest rate of the debentures assumed exceeded the cost of similar debt funding available in the market at the time of the Merger.

[11]

Represents the fair value of other liabilities assumed at the Merger date.

Acquisition_Acquisition_Detail1

Acquisition Acquisition (Detail 1) (Sterling Bancorp (Legacy) [Member], USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Oct. 31, 2013
Sterling Bancorp (Legacy) [Member]	'	'	'
Business Acquisition [Line Items]	'	'	'
Contractual principal balance at acquisition	'	'	$24,176
Principal not expected to be collection (non-accretable discount)	'	'	-10,927
Expected cash flows at acquisition	'	'	13,249
Interest component of expected cash flows (accretable discount)	'	'	0
Fair value of acquired loans	'	'	13,249
Pro Forma Information	'	'	'
Net interest income	53,188	55,011	'
Non-interest income	16,174	16,796	'
Non-interest expense	50,378	49,391	'
Net income	$11,480	$11,028	'
Earnings per share from continuing operations, basic	$0.14	$0.13	'
Earnings per share from continuing operations, diluted	$0.14	$0.13	'

Securities_Details

Securities (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	$1,173,054	$973,709
Available-for-sale Securities, Gross Unrealized Gain	4,390	5,805
Gross Unrealized Losses	-24,131	-25,121
Fair value	1,153,313	954,393
Mortgage-backed securities-residential [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	502,377	454,173
Available-for-sale Securities, Gross Unrealized Gain	1,235	2,205
Gross Unrealized Losses	-6,351	-7,195
Fair value	497,261	449,183
Investment securities [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	670,677	519,536
Available-for-sale Securities, Gross Unrealized Gain	3,155	3,600
Gross Unrealized Losses	-17,780	-17,926
Fair value	656,052	505,210
Fannie Mae [Member] | Mortgage-backed securities-residential [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	236,701	214,191
Available-for-sale Securities, Gross Unrealized Gain	557	1,168
Gross Unrealized Losses	-2,824	-3,921
Fair value	234,434	211,438
Freddie Mac [Member] | Mortgage-backed securities-residential [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	109,247	67,272
Available-for-sale Securities, Gross Unrealized Gain	348	593
Gross Unrealized Losses	-859	-236
Fair value	108,736	67,629
Ginnie Mae [Member] | Mortgage-backed securities-residential [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	14,752	3,374
Available-for-sale Securities, Gross Unrealized Gain	141	88
Gross Unrealized Losses	-67	0
Fair value	14,826	3,462
CMO/Other MBS [Member] | Mortgage-backed securities-residential [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	141,677	169,336
Available-for-sale Securities, Gross Unrealized Gain	189	356
Gross Unrealized Losses	-2,601	-3,038
Fair value	139,265	166,654
mutual funds [Domain] | Investment securities [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	4,877	0
Available-for-sale Securities, Gross Unrealized Gain	0	0
Gross Unrealized Losses	-23	0
Fair value	4,854	0
US Government Corporations and Agencies Securities [Member] | Investment securities [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	264,082	273,637
Available-for-sale Securities, Gross Unrealized Gain	32	0
Gross Unrealized Losses	-11,505	-12,090
Fair value	252,609	261,547
Corporate Debt Securities [Member] | Investment securities [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	202,225	118,575
Available-for-sale Securities, Gross Unrealized Gain	84	153
Gross Unrealized Losses	-4,546	-3,795
Fair value	197,763	114,933
Obligations of states and political subdivisions [Member] | Investment securities [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	131,782	127,324
Available-for-sale Securities, Gross Unrealized Gain	2,859	3,447
Gross Unrealized Losses	-1,547	-2,041
Fair value	133,094	128,730
Trust Preferred Securities Subject to Mandatory Redemption [Member] | Investment securities [Member]	'	'
Summary of securities available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	67,711	0
Available-for-sale Securities, Gross Unrealized Gain	180	0
Gross Unrealized Losses	-159	0
Fair value	$67,732	$0

Securities_Details_1

Securities (Details 1) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013
Held-to-maturity securities	'	'
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	$486,902	$253,999
Gross Unrealized Gains	758	1,324
Gross Unrealized Losses	-7,683	-4,427
Securities held-to-maturity at fair value	479,977	250,896
Mortgage-backed securities-residential [Member]	'	'
Held-to-maturity securities	'	'
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	163,705	156,147
Gross Unrealized Gains	129	749
Gross Unrealized Losses	-1,685	-423
Securities held-to-maturity at fair value	162,149	156,473
Investment securities [Member]	'	'
Held-to-maturity securities	'	'
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	323,197	97,852
Gross Unrealized Gains	629	575
Gross Unrealized Losses	-5,998	-4,004
Securities held-to-maturity at fair value	317,828	94,423
Fannie Mae [Member] | Mortgage-backed securities-residential [Member]	'	'
Held-to-maturity securities	'	'
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	65,336	70,502
Gross Unrealized Gains	71	399
Gross Unrealized Losses	-692	-86
Securities held-to-maturity at fair value	64,715	70,815
Freddie Mac [Member] | Mortgage-backed securities-residential [Member]	'	'
Held-to-maturity securities	'	'
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	27,040	59,869
Gross Unrealized Gains	47	317
Gross Unrealized Losses	0	-22
Securities held-to-maturity at fair value	27,087	60,164
CMO/Other MBS [Member] | Mortgage-backed securities-residential [Member]	'	'
Held-to-maturity securities	'	'
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	71,329	25,776
Gross Unrealized Gains	11	33
Gross Unrealized Losses	-993	-315
Securities held-to-maturity at fair value	70,347	25,494
Federal agencies [Member] | Investment securities [Member]	'	'
Held-to-maturity securities	'	'
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	133,994	77,341
Gross Unrealized Gains	0	0
Gross Unrealized Losses	-3,623	-3,458
Securities held-to-maturity at fair value	130,371	73,883
Obligations of states and political subdivisions [Member] | Investment securities [Member]	'	'
Held-to-maturity securities	'	'
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	187,703	19,011
Gross Unrealized Gains	615	556
Gross Unrealized Losses	-2,375	-546
Securities held-to-maturity at fair value	185,943	19,021
Other [Member] | Investment securities [Member]	'	'
Held-to-maturity securities	'	'
Held-to-maturity Securities, Amortized Cost before Other than Temporary Impairment	1,500	1,500
Gross Unrealized Gains	14	19
Gross Unrealized Losses	0	0
Securities held-to-maturity at fair value	$1,514	$1,519

Securities_Details_2

Securities (Details 2) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Available for sale	'	'
Amortized Cost, Less than one year	$41,392	'
Amortized Cost, One to five years	117,527	'
Amortized Cost, Five to ten years	387,364	'
Amortized Cost, Greater than ten years	124,394	'
Amortized Cost, Total investment securities	670,677	'
Available-for-sale Securities, Amortized Cost Basis	1,173,054	973,709
Fair Value, Less than one year	41,352	'
Fair Value, One to five years	117,328	'
Fair Value, Five to ten years	373,665	'
Fair Value, Greater than ten years	123,707	'
Fair Value, Total investment securities	656,052	'
Fair value	1,153,313	954,393
Held to maturity	'	'
Held-to-maturity Securities, Debt Maturities, within One Year, Net Carrying Amount	5,408	'
Held-to-maturity Securities, Debt Maturities, after One Through Five Years, Net Carrying Amount	5,209	'
Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Net Carrying Amount	144,734	'
Held-to-maturity Securities, Debt Maturities, after Ten Years, Net Carrying Amount	167,846	'
Held to maturity debt maturites net carrying amount	323,197	'
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount	486,902	253,999
Held-to-maturity Securities, Debt Maturities, Next Twelve Months, Fair Value	5,463	'
Held-to-maturity Securities, Debt Maturities, Year Two Through Five, Fair Value	5,471	'
Held-to-maturity Securities, Debt Maturities, Year Six Through Ten, Fair Value	141,202	'
Held-to-maturity Securities, Debt Maturities, after Ten Years, Fair Value	165,692	'
Held to maturity Debt Maturities Fair value	317,828	'
Mortgage-backed securities-residential [Member]	'	'
Available for sale	'	'
Available-for-sale Securities, Amortized Cost Basis	502,377	454,173
Fair value	497,261	449,183
Held to maturity	'	'
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount	$163,705	'

Securities_Details_3

Securities (Details 3) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Gain (Loss) on Investments [Line Items]	'	'
Proceeds from Sale of Available-for-sale Securities	$247,650	$41,965
Available-for-sale Securities, Gross Realized Gains	211	1,416
Available-for-sale Securities, Gross Realized Losses	-856	0
Tax expense of securities gains	$214	$575

Securities_Details_4

Securities (Details 4) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013
Securities available for sale with unrealized losses	'	'
Fair Value, Less Than 12 Months	$862,410	$659,734
Unrealized Losses, Less Than 12 Months	-23,941	-24,817
Fair Value, 12 Months or Longer	5,782	7,932
Unrealized Losses, 12 Months or Longer	-190	-304
Fair Value, Total	868,192	667,666
Unrealized Losses, Total	-24,131	-25,121
Agency Securities [Member]	'	'
Securities available for sale with unrealized losses	'	'
Fair Value, Less Than 12 Months	227,935	137,265
Unrealized Losses, Less Than 12 Months	-3,750	-4,157
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	227,935	137,265
Unrealized Losses, Total	-3,750	-4,157
CMO/Other MBS [Member]	'	'
Securities available for sale with unrealized losses	'	'
Fair Value, Less Than 12 Months	114,362	122,324
Unrealized Losses, Less Than 12 Months	-2,601	-2,742
Fair Value, 12 Months or Longer	0	7,820
Unrealized Losses, 12 Months or Longer	0	-296
Fair Value, Total	114,362	130,144
Unrealized Losses, Total	-2,601	-3,038
Mortgage-backed securities-residential [Member]	'	'
Securities available for sale with unrealized losses	'	'
Fair Value, Less Than 12 Months	342,297	259,589
Unrealized Losses, Less Than 12 Months	-6,351	-6,899
Fair Value, 12 Months or Longer	0	7,820
Unrealized Losses, 12 Months or Longer	0	-296
Fair Value, Total	342,297	267,409
Unrealized Losses, Total	-6,351	-7,195
mutual funds [Domain]	'	'
Securities available for sale with unrealized losses	'	'
Fair Value, Less Than 12 Months	4,877	'
Unrealized Losses, Less Than 12 Months	-23	'
Fair Value, 12 Months or Longer	0	'
Unrealized Losses, 12 Months or Longer	0	'
Fair Value, Total	4,877	'
Unrealized Losses, Total	-23	'
Federal agencies [Member]	'	'
Securities available for sale with unrealized losses	'	'
Fair Value, Less Than 12 Months	239,612	261,547
Unrealized Losses, Less Than 12 Months	-11,351	-12,090
Fair Value, 12 Months or Longer	4,846	0
Unrealized Losses, 12 Months or Longer	-154	0
Fair Value, Total	244,458	261,547
Unrealized Losses, Total	-11,505	-12,090
Obligations of states and political subdivisions [Member]	'	'
Securities available for sale with unrealized losses	'	'
Fair Value, Less Than 12 Months	56,139	43,585
Unrealized Losses, Less Than 12 Months	-1,511	-2,033
Fair Value, 12 Months or Longer	936	112
Unrealized Losses, 12 Months or Longer	-36	-8
Fair Value, Total	57,075	43,697
Unrealized Losses, Total	-1,547	-2,041
Corporate Debt Securities [Member]	'	'
Securities available for sale with unrealized losses	'	'
Fair Value, Less Than 12 Months	171,851	95,013
Unrealized Losses, Less Than 12 Months	-4,546	-3,795
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	171,851	95,013
Unrealized Losses, Total	-4,546	-3,795
Securities Investment [Member] | Trust Preferred Securities Subject to Mandatory Redemption [Member]	'	'
Securities available for sale with unrealized losses	'	'
Fair Value, Less Than 12 Months	47,634	'
Unrealized Losses, Less Than 12 Months	-159	'
Fair Value, 12 Months or Longer	0	'
Unrealized Losses, 12 Months or Longer	0	'
Fair Value, Total	47,634	'
Unrealized Losses, Total	($159)	'

Securities_Details_5

Securities (Details 5) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]	'	'
Fair Value, Less Than 12 Months	$412,980	$125,788
Unrealized Losses, Less Than 12 Months	-7,683	-4,427
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	412,980	125,788
Agency Securities [Member]	'	'
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]	'	'
Fair Value, Less Than 12 Months	50,558	10,963
Unrealized Losses, Less Than 12 Months	'	-86
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	50,558	10,963
Unrealized Losses, Total	-692	-86
CMO/Other MBS [Member]	'	'
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]	'	'
Fair Value, Less Than 12 Months	65,219	31,412
Unrealized Losses, Less Than 12 Months	-993	-337
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	65,219	31,412
Unrealized Losses, Total	-993	-337
Federal agencies [Member]	'	'
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]	'	'
Fair Value, Less Than 12 Months	132,089	73,883
Unrealized Losses, Less Than 12 Months	-3,623	-3,458
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	132,089	73,883
Unrealized Losses, Total	-3,623	-3,458
US States and Political Subdivisions Debt Securities [Member]	'	'
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]	'	'
Fair Value, Less Than 12 Months	165,114	9,530
Unrealized Losses, Less Than 12 Months	-2,375	-546
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	165,114	9,530
Unrealized Losses, Total	-2,375	-546
Residential Mortgage Backed Securities [Member]	'	'
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]	'	'
Fair Value, Less Than 12 Months	115,777	42,375
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	115,777	42,375
Unrealized Losses, Total	($1,685)	($423)

Securities_Securities_Details_

Securities Securities (Details 6) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Total Pledged Securities	$1,263,544	$1,008,466
Federal Home Loan Bank Borrowings [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Available-for-sale Securities Pledged as Collateral	810,290	199,642
Held-to-maturity Securities Pledged as Collateral	101,981	55,497
Municipal Deposits [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Available-for-sale Securities Pledged as Collateral	63,573	580,756
Held-to-maturity Securities Pledged as Collateral	282,662	167,926
Interest Rate Swap [Member]	'	'
Schedule of Trading Securities and Other Trading Assets [Line Items]	'	'
Held-to-maturity Securities Pledged as Collateral	$5,038	$4,645

Securities_Details_Textual

Securities (Details Textual) (USD $)	2 Months Ended	3 Months Ended		3 Months Ended
	Nov. 30, 2013	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2013
		Securities		CMO/Other MBS [Member]	CMO/Other MBS [Member]	Equity Securities [Member]	Significant Unobservable Inputs Level 3 [Member]	Significant Unobservable Inputs Level 3 [Member]	Significant Unobservable Inputs Level 3 [Member]
				Securities					Collateralized Mortgage Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'	'	'	'	'	'
Investment securities transferred from held to maturity to available for sale	$165,230,000	'	'	'	'	'	'	'	'
Investment securities transfered from available for sale to held to maturity	221,904,000	'	'	'	'	'	'	'	'
Managements target percentage of investment portfolio of Held to Maturity to total portfolio	'	25.00%	'	'	'	'	'	'	'
Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Number Of Securities	'	323	'	'	'	'	'	'	'
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Number Of Securities	'	2	'	'	'	'	'	'	'
Number of fixed maturity securities past due	'	0	'	'	'	'	'	'	'
Number of individual private label CMO's	'	'	'	4	'	'	'	'	'
Impairment charges incurred on CMO's	'	'	'	0	14,000	'	'	'	'
Total cumulative impairment charges on CMO's	'	'	'	136,000	'	'	'	'	'
Number of remaining securities not Other Than Temporarily Impaired Securities	'	'	'	2	'	'	'	'	'
Additional credit loss expected	'	0	'	'	'	'	'	'	'
Amount of available for sale equity security	'	1	'	'	'	'	'	'	'
Available-for-sale Securities, Amortized Cost Basis	'	1,173,054,000	973,709,000	'	'	'	'	'	3,362,000
Fair value	'	1,153,313,000	954,393,000	'	'	826,000	3,356,000	3,613,000	3,356,000
Securities considered to be below investment grade	'	'	'	2	'	'	'	'	'
Amortized cost of impaired private label CMO's	'	'	'	3,075,000	'	'	'	'	'
Fair value of impaired private label CMO's	'	'	'	3,073,000	'	'	'	'	'
Unrealized gain(loss) on investment securities transferred	$9,657	'	'	'	'	'	'	'	'
Life of investment securities transferred	'	'6 years	'	'	'	'	'	'	'

Loans_Details

Loans (Details) (USD $)	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
In Thousands, unless otherwise specified
Loans [Abstract]	'	'	'	'
Loans Receivable, Gross, Commercial and Industrial	$1,025,222	$439,787	'	'
Payroll financing	122,961	0	'	'
Warehouse lending	168,776	0	'	'
Factored receivables	146,308	0	'	'
Equipment financing	263,770	0	'	'
Total commercial	1,727,037	439,787	'	'
Commercial real estate	1,262,362	969,490	'	'
Multi-family	306,533	307,547	'	'
Acquisition, development & construction	95,787	102,494	'	'
Total commercial mortgage	1,664,682	1,379,531	'	'
Total commercial loans	3,391,719	1,819,318	'	'
Residential mortgage	527,425	400,009	'	'
Home equity lines of credit	154,102	156,995	'	'
Other consumer loans	53,895	36,576	'	'
Total consumer	207,997	193,571	'	'
Total loans	4,127,141	2,412,898	'	'
Allowance for loan losses	30,612	28,877	28,114	28,282
Total loans, net	$4,096,529	$2,384,021	'	'

Loans_Details_1

Loans (Details 1) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013
Non-Performing loans:	'	'
Current Loans	$4,008,688	$2,379,522
Non-performing loans, 30-59 Days Past Due	17,380	3,844
Non-performing loans, 60-89 Days Past Due	62,631	2,626
Non-performing loans, 90+ Days Past Due	2,845	4,099
Non accrual loans	35,597	22,807
Loans Total	4,127,141	2,412,898
Current Loans under Troubled debt restructuring	24,931	23,754
30-59 Days past due	0	0
60-89 Days past due	1,477	0
90 Days past due	273	141
Non- accrual	1,801	2,199
Total	28,482	26,094
One-to-four family residential [Member]	'	'
Non-Performing loans:	'	'
Current Loans	504,284	390,072
Non-performing loans, 30-59 Days Past Due	6,593	354
Non-performing loans, 60-89 Days Past Due	3,956	267
Non-performing loans, 90+ Days Past Due	1,767	1,832
Non accrual loans	10,825	7,484
Loans Total	527,425	400,009
Commerical real estate [Member]	'	'
Non-Performing loans:	'	'
Current Loans	1,547,358	1,263,933
Non-performing loans, 30-59 Days Past Due	3,816	1,978
Non-performing loans, 60-89 Days Past Due	990	2,357
Non-performing loans, 90+ Days Past Due	0	1,574
Non accrual loans	16,731	7,195
Loans Total	1,568,895	1,277,037
Commercial Portfolio Segment [Member]	'	'
Non-Performing loans:	'	'
Current Loans	1,670,399	438,818
Non-performing loans, 30-59 Days Past Due	22	178
Non-performing loans, 60-89 Days Past Due	54,560	2
Non-performing loans, 90+ Days Past Due	91	289
Non accrual loans	1,965	500
Loans Total	1,727,037	439,787
Acquisition, development & construction [Member]	'	'
Non-Performing loans:	'	'
Current Loans	91,035	96,306
Non-performing loans, 30-59 Days Past Due	311	768
Non-performing loans, 60-89 Days Past Due	86	0
Non-performing loans, 90+ Days Past Due	273	0
Non accrual loans	4,082	5,420
Loans Total	95,787	102,494
Consumer [Member]	'	'
Non-Performing loans:	'	'
Current Loans	195,612	190,393
Non-performing loans, 30-59 Days Past Due	6,638	566
Non-performing loans, 60-89 Days Past Due	3,039	0
Non-performing loans, 90+ Days Past Due	714	404
Non accrual loans	1,994	2,208
Loans Total	207,997	193,571
Nonperforming Financing Receivable [Member]	'	'
Non-Performing loans:	'	'
Non accrual loans	35,597	22,807
Non Performing Assets	'	'
Loans 90 days past due and still accruing	2,845	4,099
Total non-performing loans	$38,442	$26,906

Loans_Details_2

Loans (Details 2) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Summary of activity in allowance for loan losses and recorded investments in loans by portfolio segment based on impairment method	'	'
Beginning Allowance for loan losses	$28,877	$28,282
Charge-offs	-1,834	-3,414
Recoveries	-569	-296
Net charge-offs	-1,265	-3,118
Provision for losses	3,000	2,950
Ending Allowance for Loan Losses	30,612	28,114
Annualized net charge-offs to average gross loans	0.14%	0.58%
One-to-four family residential [Member]	'	'
Summary of activity in allowance for loan losses and recorded investments in loans by portfolio segment based on impairment method	'	'
Beginning Allowance for loan losses	4,474	4,359
Charge-offs	-270	-950
Recoveries	-7	-51
Net charge-offs	-263	-899
Provision for losses	389	908
Ending Allowance for Loan Losses	4,600	4,368
Commerical real estate [Member]	'	'
Summary of activity in allowance for loan losses and recorded investments in loans by portfolio segment based on impairment method	'	'
Beginning Allowance for loan losses	9,967	7,230
Charge-offs	-671	-228
Recoveries	-37	-81
Net charge-offs	-634	-147
Provision for losses	659	533
Ending Allowance for Loan Losses	9,992	7,616
Commercial Portfolio Segment [Member]	'	'
Summary of activity in allowance for loan losses and recorded investments in loans by portfolio segment based on impairment method	'	'
Beginning Allowance for loan losses	5,302	4,603
Charge-offs	-528	-159
Recoveries	-501	-120
Net charge-offs	-27	-39
Provision for losses	1,611	969
Ending Allowance for Loan Losses	6,886	5,533
Acquisition, development & construction [Member]	'	'
Summary of activity in allowance for loan losses and recorded investments in loans by portfolio segment based on impairment method	'	'
Beginning Allowance for loan losses	5,806	8,526
Charge-offs	-218	-1,594
Recoveries	0	-5
Net charge-offs	-218	-1,589
Provision for losses	269	89
Ending Allowance for Loan Losses	5,857	7,026
Consumer [Member]	'	'
Summary of activity in allowance for loan losses and recorded investments in loans by portfolio segment based on impairment method	'	'
Beginning Allowance for loan losses	3,328	3,564
Charge-offs	-147	-483
Recoveries	-24	-39
Net charge-offs	-123	-444
Provision for losses	72	451
Ending Allowance for Loan Losses	$3,277	$3,571

Loans_Details_3

Loans (Details 3) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Loans evaluated for impairment by segment	'	'
Individually evaluated for impairment	$34,197	$36,821
Collectively evaluated for impairment	4,078,290	2,376,077
Total loans	4,127,141	2,412,898
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	686	1,593
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	29,926	27,284
Financing Receivable, Allowance for Credit Losses	30,612	28,877
One-to-four family residential [Member]	'	'
Loans evaluated for impairment by segment	'	'
Individually evaluated for impairment	515	515
Collectively evaluated for impairment	523,290	399,494
Total loans	527,425	400,009
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	4,600	4,474
Financing Receivable, Allowance for Credit Losses	4,600	4,474
Commerical real estate [Member]	'	'
Loans evaluated for impairment by segment	'	'
Individually evaluated for impairment	13,482	14,091
Collectively evaluated for impairment	1,547,016	1,262,946
Total loans	1,568,895	1,277,037
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	803
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	9,992	9,164
Financing Receivable, Allowance for Credit Losses	9,992	9,967
Commercial Portfolio Segment [Member]	'	'
Loans evaluated for impairment by segment	'	'
Individually evaluated for impairment	2,272	2,631
Collectively evaluated for impairment	1,722,128	437,156
Total loans	1,727,037	439,787
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	162	249
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	6,724	5,053
Financing Receivable, Allowance for Credit Losses	6,886	5,302
Acquisition, development & construction [Member]	'	'
Loans evaluated for impairment by segment	'	'
Individually evaluated for impairment	17,928	19,582
Collectively evaluated for impairment	77,859	82,912
Total loans	95,787	102,494
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	524	540
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	5,333	5,266
Financing Receivable, Allowance for Credit Losses	5,857	5,806
Consumer [Member]	'	'
Loans evaluated for impairment by segment	'	'
Individually evaluated for impairment	0	2
Collectively evaluated for impairment	207,997	193,569
Total loans	207,997	193,571
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	1
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	3,277	3,327
Financing Receivable, Allowance for Credit Losses	3,277	3,328
Sterling Bancorp (Legacy) [Member]	'	'
Loans evaluated for impairment by segment	'	'
Recorded investment purchased credit impaired loans	14,654	'
Sterling Bancorp (Legacy) [Member] | One-to-four family residential [Member]	'	'
Loans evaluated for impairment by segment	'	'
Recorded investment purchased credit impaired loans	3,620	'
Sterling Bancorp (Legacy) [Member] | Commerical real estate [Member]	'	'
Loans evaluated for impairment by segment	'	'
Recorded investment purchased credit impaired loans	8,397	'
Sterling Bancorp (Legacy) [Member] | Commercial Portfolio Segment [Member]	'	'
Loans evaluated for impairment by segment	'	'
Recorded investment purchased credit impaired loans	2,637	'
Sterling Bancorp (Legacy) [Member] | Acquisition, development & construction [Member]	'	'
Loans evaluated for impairment by segment	'	'
Recorded investment purchased credit impaired loans	0	'
Sterling Bancorp (Legacy) [Member] | Consumer [Member]	'	'
Loans evaluated for impairment by segment	'	'
Recorded investment purchased credit impaired loans	$0	'

Loans_Details_4

Loans (Details 4) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2013
With no related allowance recorded:	'	'	'
Unpaid Principal Balance with no related allowance recorded	$55,775	'	$33,112
Recorded Investment with no related allowance recorded	46,726	'	32,411
Average Impaired Loans with no allowance recorded	45,075	36,157	'
Interest Income Recognized with no allowance recorded	220	198	'
Cash-basis Interest Income Recognized with no allowance recorded	2	134	'
With an allowance recorded:	'	'	'
Unpaid Principal Balance with an allowance recorded	3,125	'	6,405
Recorded Investment with an allowance recorded	2,125	'	4,410
Allowance for Loan Losses Allocated with an allowance recorded	686	'	1,593
QTD Average Impaired Loans with an allowance recorded	2,246	16,622	'
Interest Income Recognized with an allowance recorded	0	92	'
Cash-basis Interest Income Recognized with an allowance recorded	0	24	'
Unpaid Principal Balance Total	58,900	'	39,517
Recorded Investment Total	48,851	'	36,821
Allowance for Loan Losses Allocated Total	686	'	1,593
Average Impaired Loans Total	47,321	52,779	'
Interest Income Recognized Total	220	290	'
Cash-basis Interest Income Recognized Total	2	158	'
One-to-four family residential [Member]	'	'	'
With no related allowance recorded:	'	'	'
Unpaid Principal Balance with no related allowance recorded	4,217	'	515
Recorded Investment with no related allowance recorded	4,135	'	515
Average Impaired Loans with no allowance recorded	4,890	7,237	'
Interest Income Recognized with no allowance recorded	0	43	'
Cash-basis Interest Income Recognized with no allowance recorded	0	31	'
With an allowance recorded:	'	'	'
QTD Average Impaired Loans with an allowance recorded	0	5,484	'
Interest Income Recognized with an allowance recorded	0	17	'
Cash-basis Interest Income Recognized with an allowance recorded	0	18	'
Commerical real estate [Member]	'	'	'
With no related allowance recorded:	'	'	'
Unpaid Principal Balance with no related allowance recorded	28,027	'	12,451
Recorded Investment with no related allowance recorded	21,879	'	11,820
Average Impaired Loans with no allowance recorded	19,318	12,458	'
Interest Income Recognized with no allowance recorded	52	58	'
Cash-basis Interest Income Recognized with no allowance recorded	0	54	'
With an allowance recorded:	'	'	'
Unpaid Principal Balance with an allowance recorded	0	'	3,150
Recorded Investment with an allowance recorded	0	'	2,271
Allowance for Loan Losses Allocated with an allowance recorded	0	'	803
QTD Average Impaired Loans with an allowance recorded	0	5,025	'
Interest Income Recognized with an allowance recorded	0	14	'
Cash-basis Interest Income Recognized with an allowance recorded	0	0	'
Commercial Portfolio Segment [Member]	'	'	'
With no related allowance recorded:	'	'	'
Unpaid Principal Balance with no related allowance recorded	7,379	'	2,175
Recorded Investment with no related allowance recorded	4,597	'	2,131
Average Impaired Loans with no allowance recorded	3,759	225	'
Interest Income Recognized with no allowance recorded	20	2	'
Cash-basis Interest Income Recognized with no allowance recorded	2	0	'
With an allowance recorded:	'	'	'
Unpaid Principal Balance with an allowance recorded	312	'	500
Recorded Investment with an allowance recorded	312	'	500
Allowance for Loan Losses Allocated with an allowance recorded	162	'	249
QTD Average Impaired Loans with an allowance recorded	314	2,410	'
Interest Income Recognized with an allowance recorded	0	21	'
Cash-basis Interest Income Recognized with an allowance recorded	0	6	'
Acquisition, development & construction [Member]	'	'	'
With no related allowance recorded:	'	'	'
Unpaid Principal Balance with no related allowance recorded	16,152	'	17,971
Recorded Investment with no related allowance recorded	16,115	'	17,945
Average Impaired Loans with no allowance recorded	17,108	13,760	'
Interest Income Recognized with no allowance recorded	148	87	'
Cash-basis Interest Income Recognized with no allowance recorded	0	48	'
With an allowance recorded:	'	'	'
Unpaid Principal Balance with an allowance recorded	2,813	'	2,753
Recorded Investment with an allowance recorded	1,813	'	1,637
Allowance for Loan Losses Allocated with an allowance recorded	524	'	540
QTD Average Impaired Loans with an allowance recorded	1,932	2,919	'
Interest Income Recognized with an allowance recorded	0	40	'
Cash-basis Interest Income Recognized with an allowance recorded	0	0	'
Consumer [Member]	'	'	'
With no related allowance recorded:	'	'	'
Unpaid Principal Balance with no related allowance recorded	0	'	0
Recorded Investment with no related allowance recorded	0	'	0
Average Impaired Loans with no allowance recorded	0	2,477	'
Interest Income Recognized with no allowance recorded	0	8	'
Cash-basis Interest Income Recognized with no allowance recorded	0	1	'
With an allowance recorded:	'	'	'
Unpaid Principal Balance with an allowance recorded	0	'	2
Recorded Investment with an allowance recorded	0	'	2
Allowance for Loan Losses Allocated with an allowance recorded	0	'	1
QTD Average Impaired Loans with an allowance recorded	0	784	'
Interest Income Recognized with an allowance recorded	0	0	'
Cash-basis Interest Income Recognized with an allowance recorded	$0	$0	'

Loans_Details_5

Loans (Details 5) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013
Troubled debt restructurings	'	'
Current	$24,931	$23,754
30-59 Days past due	0	0
60-89 Days past due	1,477	0
90 Days past due	273	141
Non- accrual	1,801	2,199
Total	28,482	26,094
Trouble Debt restructuring currrent loans	24,931	23,754
Allowance, Current Loans	-759	-438
Allowance, 30-59 days past due	0	0
Allowance, 60-89 days past due	0	0
Allowance, 90+ days past due	-16	0
Allowance, Non-Accrual	0	439
Allowance, Total TDR's	775	877
Commercial Portfolio Segment [Member]	'	'
Troubled debt restructurings	'	'
30-59 Days past due	0	0
60-89 Days past due	0	0
90 Days past due	0	141
Non- accrual	136	0
Total	1,961	1,984
Trouble Debt restructuring currrent loans	1,825	1,843
One-to-four family residential [Member]	'	'
Troubled debt restructurings	'	'
30-59 Days past due	0	0
60-89 Days past due	1,477	0
90 Days past due	0	0
Non- accrual	1,465	1,792
Total	7,122	4,208
Trouble Debt restructuring currrent loans	4,180	2,416
Commerical real estate [Member]	'	'
Troubled debt restructurings	'	'
30-59 Days past due	0	0
60-89 Days past due	0	0
90 Days past due	0	0
Non- accrual	62	0
Total	5,363	5,305
Trouble Debt restructuring currrent loans	5,301	5,305
Acquisition, development & construction [Member]	'	'
Troubled debt restructurings	'	'
30-59 Days past due	0	0
60-89 Days past due	0	0
90 Days past due	273	0
Non- accrual	138	151
Total	14,036	14,341
Trouble Debt restructuring currrent loans	13,625	14,190
Consumer Other Financing Receivable [Member]	'	'
Troubled debt restructurings	'	'
Current	'	0
30-59 Days past due	'	0
60-89 Days past due	'	0
90 Days past due	'	0
Non- accrual	'	256
Total	'	$256

Loans_Details_6

Loans (Details 6) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
	loans	loans
Restructured Loans:	'	'
Number of loans	0	5
Pre-Modification	$0	$4,948
Post-Modification	0	4,948
One-to-four family residential [Member]	'	'
Restructured Loans:	'	'
Number of loans	0	1
Pre-Modification	0	275
Post-Modification	0	275
Commerical real estate [Member]	'	'
Restructured Loans:	'	'
Number of loans	0	1
Pre-Modification	0	450
Post-Modification	0	450
Commercial Portfolio Segment [Member]	'	'
Restructured Loans:	'	'
Number of loans	0	'
Pre-Modification	0	1,500
Post-Modification	0	1,500
Acquisition, development & construction [Member]	'	'
Restructured Loans:	'	'
Number of loans	0	2
Pre-Modification	0	2,723
Post-Modification	$0	$2,723

Loans_Details_7

Loans (Details 7) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Doubtful [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	$312	$592
Doubtful [Member] | One-to-four family residential [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	0	0
Doubtful [Member] | Commerical real estate [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	0	227
Doubtful [Member] | Acquisition, development & construction [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	0	0
Doubtful [Member] | Commercial Portfolio Segment [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	312	365
Doubtful [Member] | Consumer [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	0	0
Doubtful [Member] | Payroll financing [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	0	0
Doubtful [Member] | Factored receivable [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	0	0
Doubtful [Member] | Finance Leases Portfolio Segment [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	0	0
Substandard [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	77,025	60,503
Substandard [Member] | One-to-four family residential [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	14,841	9,786
Substandard [Member] | Commerical real estate [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	30,132	24,561
Substandard [Member] | Acquisition, development & construction [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	19,336	19,410
Substandard [Member] | Commercial Portfolio Segment [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	7,644	3,855
Substandard [Member] | Consumer [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	4,531	2,891
Substandard [Member] | Payroll financing [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	476	0
Substandard [Member] | Factored receivable [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	0	0
Substandard [Member] | Finance Leases Portfolio Segment [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	65	0
Special Mention [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	38,834	13,530
Special Mention [Member] | One-to-four family residential [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	3,290	824
Special Mention [Member] | Commerical real estate [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	7,448	7,279
Special Mention [Member] | Acquisition, development & construction [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	524	1,867
Special Mention [Member] | Commercial Portfolio Segment [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	20,822	3,545
Special Mention [Member] | Consumer [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	3,488	15
Special Mention [Member] | Payroll financing [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	0	0
Special Mention [Member] | Factored receivable [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	3,262	0
Special Mention [Member] | Finance Leases Portfolio Segment [Member]	'	'
Risk category of loans by segment of gross loans	'	'
Risk Category of loans by Segment of loans	$0	$0

Loans_Details_Textual

Loans (Details Textual) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2013
Loans (Textual) [Abstract]	'	'	'
Net deferred loan origination Fees and Costs	($1,179)	'	($1,201)
Increased allowance for loan losses	0	218	'
Charge offs resulting from troubled debt restructurings	0	0	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'
Gotham Loans aquired carried at fair value	'	'	133,493
Pledged Assets Separately Reported, Loans Pledged as Collateral, at Fair Value	921,122	'	784,422
Additional restricted loan [Member]	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'
Additional restricted loan	0	'	4,101
Gotham Bank of New York / legacy Sterling Bancorp [Member]	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Loans Acquired	1,873,076	'	'
Sterling Bancorp (Legacy) [Member]	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'
Financing Receivable, Acquired with Deteriorated Credit Quality	14,654	'	'
Impaired [Member] | Sterling Bancorp (Legacy) [Member]	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'
Financing Receivable, Acquired with Deteriorated Credit Quality	14,654	'	'
Carrying amount of loans not impaired [Domain] | Gotham Bank of New York / legacy Sterling Bancorp [Member]	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Loans Acquired	$1,858,422	'	'

Deposits_Details

Deposits (Details) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Summary of major classification of deposits	'	'
Noninterest-bearing Domestic Deposit, Demand	$1,575,174	$943,934
Interest-bearing Domestic Deposit, Demand	775,618	434,398
Savings	605,168	580,125
Money market	1,314,419	735,709
Certificates Of Deposit	650,185	268,128
Total deposits	$4,920,564	$2,962,294

Deposits_Details_1

Deposits (Details 1) (USD $)	Dec. 31, 2013		Sep. 30, 2013
In Thousands, unless otherwise specified
Schedule of Classification of Deposits [Line Items]	'		'
Noninterest-bearing Domestic Deposit, Brokered	$92,674		$36,682
Money Market Deposits [Member]	'		'
Schedule of Classification of Deposits [Line Items]	'		'
Noninterest-bearing Domestic Deposit, Brokered	59,069		34,571
Reciprocal CDAR's [Member]	'		'
Schedule of Classification of Deposits [Line Items]	'		'
Noninterest-bearing Domestic Deposit, Brokered	25,331	[1]	1,343	[1]
CDAR's One Way [Member]	'		'
Schedule of Classification of Deposits [Line Items]	'		'
Noninterest-bearing Domestic Deposit, Brokered	$8,274		$768
[1]	Certificate of deposit account registry service.

Deposits_Details_Textual

Deposits (Details Textual) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Deposits (Textual) [Abstract]	'	'
Municipal deposits	$673,656	$757,066

Borrowings_Details

Borrowings (Details) (USD $)	Dec. 31, 2013	Sep. 30, 2013	Jul. 02, 2013
In Thousands, unless otherwise specified
By period to maturity:	'	'	'
Less than one year, Amount	$119,573	$158,897	'
Less than one year, Rate	0.63%	0.95%	'
One to two years, Amount	96,511	78,717	'
One to two years, Rate	0.85%	1.97%	'
Two to three years, Amount	132,863	191	'
Two to three years, Rate	0.70%	5.32%	'
Three to four years, Amount	200,000	202,414	'
Three to four years, Rate	4.23%	4.21%	'
Four to five years, Amount	118,124	118,033	'
Four to five years, Rate	5.57%	5.57%	'
Greater than five years, Amount	2,680	2,734	'
Greater than five years, Rate	4.92%	4.92%	'
Total borrowings, Amount	669,751	560,986	'
Total borrowings, Rate	2.64%	3.26%	'
FHLB Advances [Member]	'	'	'
By period to maturity:	'	'	'
Total borrowings, Amount	489,787	442,602	'
Total borrowings, Rate	2.29%	2.77%	'
Commercial Paper [Member]	'	'	'
By period to maturity:	'	'	'
Total borrowings, Amount	20,658	0	'
Total borrowings, Rate	0.31%	0.00%	'
Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member]	'	'	'
By period to maturity:	'	'	'
Total borrowings, Amount	61,183	20,351	'
Total borrowings, Rate	0.87%	0.88%	'
Senior Notes [Member]	'	'	'
By period to maturity:	'	'	'
Total borrowings, Amount	$98,123	$98,033	$100,000
Total borrowings, Rate	5.98%	5.98%	'

Borrowings_Details_Textual

Borrowings (Details Textual) (USD $)	3 Months Ended	12 Months Ended			12 Months Ended			3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2013	Sep. 30, 2013	Sep. 30, 2013	Dec. 31, 2013	Jul. 02, 2013	Dec. 31, 2013	Dec. 31, 2013
			Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member]	Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member]	Senior Notes [Member]	Senior Notes [Member]	Senior Notes [Member]	Sterling Bancorp (Legacy) [Member]	Sterling Bancorp (Legacy) [Member]
									Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member]
Borrowings (Textual) [Abstract]	'	'	'	'	'	'	'	'	'
Debt Issuance Cost	'	'	'	'	$303	'	'	'	'
Repurchase agreements	10,000	'	'	'	'	'	'	40,919	'
Debt, Weighted Average Interest Rate	4.23%	4.23%	'	'	'	'	'	'	0.35%
Debt Instrument, Unamortized Discount	'	'	'	'	1,967	1,877	'	'	'
Interest expense cost over the life of Senior note	5.98%	'	'	'	'	'	'	'	'
Private placement discount rate	'	1.75%	'	'	'	'	'	'	'
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate	'	'	'	'	'	'	5.50%	'	'
Bank pledged mortgages	921,122	784,422	'	'	'	'	'	'	'
Long-term Debt	669,751	560,986	61,183	20,351	98,033	98,123	100,000	'	'
Market Value Of Mortgage Not Required To Be Pledged	679,715	'	'	'	'	'	'	'	'
Federal home loan bank borrowings	$200,000	$200,000	'	'	'	'	'	'	'
Long term debt weighted average remaining term	'3 years 3 months 22 days	'3 years 6 months 22 days	'	'	'	'	'	'	'
Amount of repurchase agreements	2	'	'	'	'	'	'	'	'
Long-term Debt, Weighted Average Interest Rate	2.64%	3.26%	0.87%	0.88%	5.98%	5.98%	'	'	'
Repurchase agreement remaining terms	'	'	'	'	'	'	'	'0 years 0 months 14 days	'

Subordinated_Debentures_Subord2

Subordinated Debentures Subordinated Debentures (Details) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Subordinated Debentures [Abstract]	'	'
Subordinated debentures	$25,774	$0
Amortization of Debt Discount (Premium)	745	0
Subordinated debentures	$26,519	$0

Subordinated_Debentures_Subord3

Subordinated Debentures Subordinated debentures textural (Details1) (USD $)	Dec. 31, 2013	Sep. 30, 2013	Feb. 28, 2002	Feb. 28, 2002	Dec. 31, 2013
				Sterling Bancorp Trust I [Member]	Trust Preferred Securities Subject to Mandatory Redemption [Member]
					Sterling Bancorp [Member]
Subordinated Borrowing [Line Items]	'	'	'	'	'
Proceeds from Issuance of Trust Preferred Securities	'	'	'	$25,000	'
Debt Instrument, Interest Rate, Stated Percentage	'	'	8.38%	'	'
Securities available for sale	1,153,313,000	954,393,000	'	'	1,013,000
Junior Subordinated Notes	25,774,000	0	'	'	'
Trust preferred capital securities not owned	$23,987	'	'	'	'

Guarantors_Obligations_Under_G1

Guarantor's Obligations Under Guarantees (Details) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Guarantor's Obligations Under Guarantees (Textual) [Abstract]	'
Outstanding letters of credit	$79,811
Outstanding letters of credit cash secured	22,218
Outstanding letters of credit secured by collateral	$14,689

Earnings_Per_Common_Share_Deta

Earnings Per Common Share (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Computation of basic and diluted earnings per share	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	2,025,501	1,358,812
Basic earnings per common share	'	'
Weighted average common shares outstanding (basic)	70,493,305	43,637,315
Net income	($14,002)	$7,020
Basic earnings per common share	($0.20)	$0.16
Diluted earnings per common share	'	'
Weighted average common shares outstanding (basic)	70,493,305	43,637,315
Effect of common stock equivalents	0	83,776
Weighted average common shares diluted	70,493,305	43,721,091
Net income	($14,002)	$7,020
Diluted earnings per common share	($0.20)	$0.16

Other_Noninterest_expense_Othe2

Other Non-interest expense Other Non-interest expense (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Other Non-Interest Expense [Abstract]	'	'
Marketing and Advertising Expense	$309	$244
Professional Fees	1,818	1,215
Information Technology and Data Processing	595	649
Other non interest expense -misc	4,733	2,565
Other Noninterest Expense	$7,455	$4,673

StockBased_Compensation_Detail

Stock-Based Compensation (Details) (Restricted Stock Units (RSUs) [Member])	3 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Restricted Stock Units (RSUs) [Member]	'		'
Fair value of options granted determined using weighted-average assumptions as grant date	'		'
Risk-free interest rate	1.74%		0.96%
Expected stock price volatility	26.50%		40.80%
Dividend yield	2.05%	[1]	2.61%	[1]
Expected term in years	'5 years 9 months		'5 years 9 months
[1]	Represents the approximate annualized cash dividend rate paid with respect to a share of common stock at or near the grant date

StockBased_Compensation_Detail1

Stock-Based Compensation (Details 1) (USD $)	3 Months Ended
	Dec. 31, 2013
Summary of Company's stock option activity	'
Granted, Number of Shares	595,435
Exercised, Number of Shares	0
Forfeited, Number of Shares	-36,656
Outstanding at end of period, Number of Shares	585,902
Stock Compensation Plan [Member]	'
Summary of Company's stock option activity	'
Exercisable at end of period, Number of Shares	1,293,662
Summary of Company's stock option activity, weighted average exercise price	'
Exercisable at end of period, Weighted Average Exercise Price (USD per share)	11.64
Recognition and Retention Plan [Member] | Restricted Stock Units (RSUs) [Member]	'
Summary of restricted stock award activity	'
Nonvested shares at beginning of period, Number of Shares	209,697
Granted, Number of Shares	-101,078
Vested, Number of Shares	-44,523
Forfeited, Number of Shares	0
Nonvested shares at end of period, Number of Shares	618,216
Summary of restricted stock award activity, weighted average grant date fair value	'
Nonvested shares at beginning of period, Weighted Average Grant-Date Fair Value	8.73
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	11.36
Vested, Weighted Average Grant-Date Fair Value	8.73
Forfeited, Weighted Average Grant-Date Fair Value	0
Nonvested shares at end of period, Weighted Average Grant-Date Fair Value	10.83
Employee Stock Option [Member]	'
Summary of Company's stock option activity	'
Outstanding at beginning of period, Number of Shares	2,114,509
Granted, Number of Shares	249,862
Exercised, Number of Shares	-338,177
Forfeited, Number of Shares	-36,656
Outstanding at end of period, Number of Shares	2,093,690
Summary of Company's stock option activity, weighted average exercise price	'
Outstanding at beginning of period, Weighted Average Exercise Price (USD per share)	10.71
Granted, Weighted Average Exercise Price (USD per share)	11.36
Exercised, Weighted Average Exercise Price (USD per share)	12.16
Forfeited, Weighted Average Exercise Price (USD per share)	8.59
Outstanding at end of period, Weighted Average Exercise Price (USD per share)	10.77
Stock Compensation Grants associated with legacy Sterling Merger [Member]	'
Summary of Company's stock option activity	'
Granted, Number of Shares	921,503
Stock Compensation Grants associated with legacy Sterling Merger [Member] | Recognition and Retention Plan [Member] | Restricted Stock Units (RSUs) [Member]	'
Summary of restricted stock award activity	'
Granted, Number of Shares	-351,964
Summary of restricted stock award activity, weighted average grant date fair value	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	11.72
Stock Compensation Grants associated with legacy Sterling Merger [Member] | Employee Stock Option [Member]	'
Summary of Company's stock option activity	'
Granted, Number of Shares	104,152
Summary of Company's stock option activity, weighted average exercise price	'
Granted, Weighted Average Exercise Price (USD per share)	14.25

StockBased_Compensation_Detail2

Stock-Based Compensation (Details Textual) (USD $)	3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 30, 2013	Sep. 30, 2013
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost	$0	'	'	'
Total compensation cost that has been charged against income for share based compensation plan	991,000	500,000	'	'
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	0	'	'	'
Grant of share options to employees as per Employee Share Option Plan (stock option plan)	595,435	'	'	'
Shares remaining that are authorized and available for future grant under the 2004 RRP	'	'	77	2,066,184
Number of shares received for each share granted	3.6	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	36,656	'	'	'
Weighted average fair value of options granted	$2.49	$2.74	'	'
Total unrecognized compensation cost related to non-vested shares granted under the 2004 RRP	1,704,000	'	'	'
Weighted-average period total unrecognized compensation cost related to non-vested shares granted under the 2004 RRP	'2 years 0 months 23 days	'	'	'
Employee Stock Option [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Grant of share options to employees as per Employee Share Option Plan (stock option plan)	249,862	'	'	'
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$11.36	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	36,656	'	'	'
Recognition and Retention Plan [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Total unrecognized compensation cost related to non-vested shares granted under the 2004 RRP	5,892,000	'	'	'
Weighted-average period total unrecognized compensation cost related to non-vested shares granted under the 2004 RRP	'2 years 5 months 27 days	'	'	'
Employee Stock Option [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Total compensation cost that has been charged against income for share based compensation plan	$991,000	$384,000	'	'
Restricted Stock Units (RSUs) [Member] | Recognition and Retention Plan [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	101,078	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$11.36	'	'	'
Share Option Plan 2012 [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Grant of share options to employees as per Employee Share Option Plan (stock option plan)	561,995	'	'	'
Term of Contract	'10 years 0 months 0 days	'	'	'
Share Option Plan 2012 [Member] | Minimum [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Vesting period for Option awards	'2 years 0 months 0 days	'	'	'
Share Option Plan 2012 [Member] | Maximum [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Vesting period for Option awards	'5 years 0 months 0 days	'	'	'
Share Option Plan 2004 [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Grant of share options to employees as per Employee Share Option Plan (stock option plan)	20,674	'	'	'
Term of Contract	'10 years 0 months 0 days	'	'	'
Share Option Plan 2004 [Member] | Minimum [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Vesting period for Option awards	'2 years 0 months 0 days	'	'	'
Share Option Plan 2004 [Member] | Maximum [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Vesting period for Option awards	'5 years 0 months 0 days	'	'	'
Sterling Bancorp (Legacy) [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	3,156	'	'	'
Sterling Bancorp (Legacy) [Member] | Sterling Bancorp 2013 Employment Inducement Award Plan [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Grant of share options to employees as per Employee Share Option Plan (stock option plan)	95,991	'	'	'
Sterling Bancorp (Legacy) [Member] | Maximum [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Vesting period for Option awards	'3 years	'	'	'
Sterling Bancorp (Legacy) [Member] | Fully Vested legacy Sterling options [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Grant of share options to employees as per Employee Share Option Plan (stock option plan)	110,470	'	'	'
Sterling Bancorp (Legacy) [Member] | Restricted Stock Units (RSUs) [Member] | 2012 Stock Plan [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	255,973	'	'	'
Stock Compensation Grants associated with legacy Sterling Merger [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Grant of share options to employees as per Employee Share Option Plan (stock option plan)	921,503	'	'	'
Stock Compensation Grants associated with legacy Sterling Merger [Member] | Employee Stock Option [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Grant of share options to employees as per Employee Share Option Plan (stock option plan)	104,152	'	'	'
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$14.25	'	'	'
Stock Compensation Grants associated with legacy Sterling Merger [Member] | Restricted Stock Units (RSUs) [Member] | Recognition and Retention Plan [Member]	'	'	'	'
Stock Based Compensation (Textual) [Abstract]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	351,964	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$11.72	'	'	'

Pension_and_Other_Post_Retirem2

Pension and Other Post Retirement Plans (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Pension Plan [Member]	'	'
Net post-retirement cost, recorded within salaries and employee benefits expense	'	'
Service cost	$0	$0
Interest cost	402	363
Expected return on plan assets	-672	-616
Amortization of net transition obligation	0	0
Amortization of prior service cost	0	0
Amortization of (gain) or loss	97	516
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements	2,743	0
Total cost	2,570	263
Other Post Retirement Plans [Member]	'	'
Net post-retirement cost, recorded within salaries and employee benefits expense	'	'
Service cost	12	11
Interest cost	34	31
Expected return on plan assets	0	0
Amortization of net transition obligation	6	6
Amortization of prior service cost	12	12
Amortization of (gain) or loss	0	-6
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements	0	0
Total cost	$64	$54

Pension_and_Other_Post_Retirem3

Pension and Other Post Retirement Plans (Details) (Textual) (USD $)

3 Months Ended

3 Months Ended

3 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2013

Oct. 31, 2013

Dec. 31, 2013

Oct. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Feb. 04, 2014

Feb. 04, 2014

United States Pension Plan of US Entity, Defined Benefit [Member]

United States Pension Plan of US Entity, Defined Benefit [Member]

Supplemental Employee Retirement Plan, Defined Benefit [Member]

Supplemental Employee Retirement Plan, Defined Benefit [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Sterling Bancorp (Legacy) [Member]

Employee Stock Ownership Plan [Member]

Employee Stock Ownership Plan [Member]

Employee Stock Ownership Plan (ESOP) loan repayment [Member]

Supplemental Employee Retirement Plan, Defined Benefit [Member]

legacy Sterling/ National Bank employees' Retirement Plan [Member]

legacy Sterling/ National Bank employees' Retirement Plan [Member]

Unfunded post retirement obligation, Insurance benefits [Member]

Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

Employee Stock Ownership Plan (ESOP), Number of Allocated Shares

'

'

'

'

'

'

'

'

'

'

'

10,927

'

Defined benefit plan contributions by employer supplemental (SERP)

$0

$9,000

'

'

'

'

'

'

'

'

'

'

'

Employee stock ownership plan percent automatically vested upon termination

100.00%

'

'

'

'

'

'

'

'

'

'

'

'

Periodic pension expense for the supplemental plan

18,000

13,000

'

'

'

'

'

33,000

'

70,000

'

'

'

Contributions to fund benefit payments related to the SERP

0

'

'

'

'

'

'

'

'

'

'

'

'

Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Projected Benefit Obligation

'

'

17,980,000

31,705,000

1,203,000

1,238,000

'

'

'

'

'

'

'

Settlement of a portion of pension plan liability through acquisition of annuity contracts

'

'

'

13,698,000

'

'

'

'

'

'

'

'

'

Defined Benefit Plan, Funded Status of Plan

'

'

3,489,000

3,712,000

'

'

'

'

'

'

'

'

'

Accelerated amortization of accumulated other comprehensive income (loss)

2,743,000

'

'

'

'

'

'

'

'

'

'

'

'

Business combination pension liability assumed

'

'

'

'

'

'

41,412,000

'

'

'

'

'

'

Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase

'

'

'

'

'

'

'

'

4.40%

'

'

'

'

Defined Benefit Plan, Fair Value of Plan Assets

'

'

'

'

'

'

'

73,000,000

'

'

'

'

'

Defined Benefit Plan, Benefit Obligation

'

'

'

'

'

'

'

54,000,000

'

'

'

'

'

Post-retirement benefit obligation

'

'

'

'

'

'

'

'

'

8,798,000

'

'

'

Employee Stock Ownership Plan (ESOP), Shares in ESOP

'

'

'

'

'

'

'

'

'

'

'

499,330

488,403

Employee Stock Ownership Plan (ESOP), Debt Structure, Direct Loan, Amount

'

'

'

'

'

'

'

'

'

'

'

5,983,000

'

Employee Stock Ownership Plan (ESOP), Compensation Expense

'

'

'

'

'

'

'

'

'

'

$268,000

'

'

Derivatives_Details

Derivatives (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013
Interest Rate Caps [Member]	'	'
Summary of derivatives	'	'
Notional amount	$50,000	$50,000
Weighted average maturity (in years)	'0 years 11 months 0 days	'1 year 2 months 5 days
Weighted average fixed rate	3.75%	3.75%
Fair value	0	0
3rd party interest rate swap [Member]	'	'
Summary of derivatives	'	'
Notional amount	53,666	54,180
Weighted average maturity (in years)	'5 years 6 months 5 days	'5 years 9 months 5 days
Weighted average fixed rate	4.22%	4.22%
Basis Spread on Variable Rate	2.45%	2.45%
Fair value	'	997
3rd party interest rate swap [Member] | One Month Libor [Member]	'	'
Summary of derivatives	'	'
Weighted average variable rate	'1 m Libor + 2.45	'1 m Libor + 2.45
Customer interest rate swap [Member]	'	'
Summary of derivatives	'	'
Notional amount	53,666	54,180
Weighted average maturity (in years)	'5 years 6 months 5 days	'5 years 9 months 5 days
Weighted average fixed rate	4.22%	4.22%
Basis Spread on Variable Rate	2.45%	2.45%
Fair value	$621	$997
Customer interest rate swap [Member] | One Month Libor [Member]	'	'
Summary of derivatives	'	'
Weighted average variable rate	'1 m Libor + 2.45	'1 m Libor + 2.45

Derivatives_Details_Textual

Derivatives (Details Textual) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2009
			Derivatives
Credit Derivatives [Line Items]	'	'	'
Securities pledged as collateral for Dervatives Amortized cost	$5,038	'	'
Securities pledged as collteral for derivatives at fair vaue	4,572	'	'
Interest Rate Caps [Member]	'	'	'
Credit Derivatives [Line Items]	'	'	'
Number of interest rate derivatives held	'	'	2
Strike price	'	'	3.50%
Changes in fair value	$0	$1	'
Interest Rate Cap 2 [Member]	'	'	'
Credit Derivatives [Line Items]	'	'	'
Strike price	'	'	4.00%

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Investment grades of securities	'	'
Available-for-sale Securities, Amortized Cost Basis	$1,173,054	$973,709
Fair value	1,153,313	954,393
Significant Unobservable Inputs Level 3 [Member]	'	'
Investment grades of securities	'	'
Fair value	3,356	3,613
Significant Unobservable Inputs Level 3 [Member] | Collateralized Mortgage Obligations [Member]	'	'
Investment grades of securities	'	'
Available-for-sale Securities, Amortized Cost Basis	3,362	'
Fair value	3,356	'
Significant Unobservable Inputs Level 3 [Member] | Collateralized Mortgage Obligations [Member] | Moody's, Baa1 Rating [Member]	'	'
Investment grades of securities	'	'
Available-for-sale Securities, Amortized Cost Basis	187	'
Fair value	188	'
Significant Unobservable Inputs Level 3 [Member] | Collateralized Mortgage Obligations [Member] | Moody's, Ba1 Rating [Member]	'	'
Investment grades of securities	'	'
Available-for-sale Securities, Amortized Cost Basis	100	'
Fair value	95	'
Significant Unobservable Inputs Level 3 [Member] | Collateralized Mortgage Obligations [Member] | Moody's, B1 Rating [Member]	'	'
Investment grades of securities	'	'
Available-for-sale Securities, Amortized Cost Basis	1,790	'
Fair value	1,786	'
Significant Unobservable Inputs Level 3 [Member] | Collateralized Mortgage Obligations [Member] | Moody's, B3 Rating [Member]	'	'
Investment grades of securities	'	'
Available-for-sale Securities, Amortized Cost Basis	1,285	'
Fair value	$1,287	'

Fair_Value_Measurements_Detail1

Fair Value Measurements (Details 1) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Investment securities	'	'
Fair value	$1,153,313	$954,393
Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	'	114,933
Fair Value Measurements [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	497,261	449,183
Investment securities	'	'
Investments, Fair Value Disclosure	656,052	505,210
Fair value	1,153,313	954,393
Interest rate caps and swaps	621	997
Total assets measured at estimated fair value on a recurring basis	1,153,934	955,390
Interest rate swaps	-621	-997
Total liabilities measured at estimated fair value on a recurring basis	621	997
Fair Value Measurements [Member] | Fannie Mae [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	234,434	211,438
Fair Value Measurements [Member] | Freddie Mac [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	108,736	67,629
Fair Value Measurements [Member] | Ginnie Mae [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	14,826	3,462
Fair Value Measurements [Member] | CMO/Other MBS [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	135,909	163,041
Fair Value Measurements [Member] | Privately issued collateralized mortgage obligations [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	3,356	3,613
Fair Value Measurements [Member] | US Government Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	4,854	'
Fair Value Measurements [Member] | Federal Agencies [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	252,609	261,547
Fair Value Measurements [Member] | Corporate Bond Securities [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	197,763	'
Fair Value Measurements [Member] | Obligations of states and political subdivisions [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	133,094	128,730
Fair Value Measurements [Member] | Trust Preferred Securities Subject to Mandatory Redemption [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	67,732	'
Quoted Prices in Active markets for Identical Assets Level 1 [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	'	0
Fair value	0	0
Interest rate caps and swaps	0	0
Interest rate swaps	0	0
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Investment securities	'	'
Investments, Fair Value Disclosure	0	'
Fair value	0	0
Interest rate caps and swaps	0	0
Total assets measured at estimated fair value on a recurring basis	0	0
Interest rate swaps	0	0
Total liabilities measured at estimated fair value on a recurring basis	0	0
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | Fannie Mae [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | Freddie Mac [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | Ginnie Mae [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | CMO/Other MBS [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | Privately issued collateralized mortgage obligations [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	0	'
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | Federal Agencies [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	0	0
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	0	0
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | Obligations of states and political subdivisions [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	0	0
Quoted Prices in Active markets for Identical Assets Level 1 [Member] | Trust Preferred Securities Subject to Mandatory Redemption [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	0	'
Significant Other Observable Inputs Level 2 [Member]	'	'
Investment securities	'	'
Fair value	1,149,957	950,780
Interest rate caps and swaps	621	997
Interest rate swaps	-621	-997
Significant Other Observable Inputs Level 2 [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	493,905	445,570
Investment securities	'	'
Investments, Fair Value Disclosure	656,052	505,210
Fair value	1,149,957	950,780
Interest rate caps and swaps	621	997
Total assets measured at estimated fair value on a recurring basis	1,150,578	951,777
Interest rate swaps	-621	-997
Total liabilities measured at estimated fair value on a recurring basis	621	997
Significant Other Observable Inputs Level 2 [Member] | Fannie Mae [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	234,434	211,438
Significant Other Observable Inputs Level 2 [Member] | Freddie Mac [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	108,736	67,629
Significant Other Observable Inputs Level 2 [Member] | Ginnie Mae [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	14,826	3,462
Significant Other Observable Inputs Level 2 [Member] | CMO/Other MBS [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	135,909	163,041
Significant Other Observable Inputs Level 2 [Member] | Privately issued collateralized mortgage obligations [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Significant Other Observable Inputs Level 2 [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	4,854	'
Significant Other Observable Inputs Level 2 [Member] | Federal Agencies [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	252,609	261,547
Significant Other Observable Inputs Level 2 [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	197,763	114,933
Significant Other Observable Inputs Level 2 [Member] | Obligations of states and political subdivisions [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	133,094	128,730
Significant Other Observable Inputs Level 2 [Member] | Trust Preferred Securities Subject to Mandatory Redemption [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	67,732	'
Significant Unobservable Inputs Level 3 [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	'	0
Fair value	3,356	3,613
Interest rate caps and swaps	0	0
Interest rate swaps	0	0
Significant Unobservable Inputs Level 3 [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	3,356	3,613
Investment securities	'	'
Investments, Fair Value Disclosure	0	'
Fair value	3,356	3,613
Interest rate caps and swaps	0	0
Total assets measured at estimated fair value on a recurring basis	3,356	3,613
Interest rate swaps	0	0
Total liabilities measured at estimated fair value on a recurring basis	0	0
Significant Unobservable Inputs Level 3 [Member] | Fannie Mae [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Significant Unobservable Inputs Level 3 [Member] | Freddie Mac [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Significant Unobservable Inputs Level 3 [Member] | Ginnie Mae [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Significant Unobservable Inputs Level 3 [Member] | CMO/Other MBS [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	0	0
Significant Unobservable Inputs Level 3 [Member] | Privately issued collateralized mortgage obligations [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Mortgage-backed securities-residential	'	'
Mortgage-backed securities-residential	3,356	3,613
Significant Unobservable Inputs Level 3 [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	0	'
Significant Unobservable Inputs Level 3 [Member] | Federal Agencies [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	0	0
Significant Unobservable Inputs Level 3 [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	0	0
Significant Unobservable Inputs Level 3 [Member] | Obligations of states and political subdivisions [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	0	0
Significant Unobservable Inputs Level 3 [Member] | Trust Preferred Securities Subject to Mandatory Redemption [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Investment securities	'	'
Investments, Fair Value Disclosure	0	'
Mortgage-backed securities-residential [Member]	'	'
Investment securities	'	'
Fair value	$497,261	$449,183

Fair_Value_Measurements_Detail2

Fair Value Measurements (Details 2) (Fair Value, Measurements, Recurring [Member], Significant Unobservable Inputs Level 3 [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs Level 3 [Member]	'	'
Summary of changes in Level 3 assets measured at fair value on a recurring basis	'	'
Beginning Balance	$3,613	$4,630
Pay-downs	-275	-325
Amortization, net	0	6
OTTI	0	-14
Change in fair value	18	63
Ending Balance	$3,356	$4,360

Fair_Value_Measurements_Detail3

Fair Value Measurements (Details 3) (USD $)	Dec. 31, 2013	Sep. 30, 2013
In Thousands, unless otherwise specified
Quoted Prices in Active markets for Identical Assets Level 1 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	$0	$0
Significant Other Observable Inputs Level 2 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	0	0
Significant Unobservable Inputs Level 3 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	4,150,709	2,422,824
Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	4,897	6,013
Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active markets for Identical Assets Level 1 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	0	'
Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs Level 2 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	0	0
Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs Level 3 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	4,897	6,013
Commercial business loans [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	311	500
Commercial business loans [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active markets for Identical Assets Level 1 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	0	0
Commercial business loans [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs Level 2 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	0	0
Commercial business loans [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs Level 3 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	311	500
Commercial Real Estate [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	2,332	3,672
Commercial Real Estate [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active markets for Identical Assets Level 1 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	0	0
Commercial Real Estate [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs Level 2 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	0	'
Commercial Real Estate [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs Level 3 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	2,332	'
Acquisition, development and construction [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	2,254	1,839
Acquisition, development and construction [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active markets for Identical Assets Level 1 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	0	'
Acquisition, development and construction [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs Level 2 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	0	'
Acquisition, development and construction [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs Level 3 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	2,254	'
Consumer loans [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value Measurements [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	'	2
Impaired [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active markets for Identical Assets Level 1 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	'	0
Impaired [Member] | Commercial Real Estate [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs Level 2 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	'	0
Impaired [Member] | Commercial Real Estate [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs Level 3 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	'	3,672
Impaired [Member] | Acquisition, development and construction [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active markets for Identical Assets Level 1 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	'	0
Impaired [Member] | Acquisition, development and construction [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs Level 2 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	'	0
Impaired [Member] | Acquisition, development and construction [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs Level 3 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	'	1,839
Impaired [Member] | Consumer loans [Member] | Fair Value, Measurements, Nonrecurring [Member] | Quoted Prices in Active markets for Identical Assets Level 1 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	'	0
Impaired [Member] | Consumer loans [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Other Observable Inputs Level 2 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	'	0
Impaired [Member] | Consumer loans [Member] | Fair Value, Measurements, Nonrecurring [Member] | Significant Unobservable Inputs Level 3 [Member]	'	'
Impaired loans measured at estimated fair value on nonrecurring basis	'	'
Loans, net	'	$2

Fair_Value_Measurements_Fair_v

Fair Value Measurements Fair value measurements (Details 4) (USD $)

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

In Thousands, unless otherwise specified

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Impaired [Member]

Impaired [Member]

Impaired [Member]

Impaired [Member]

Impaired [Member]

Impaired [Member]

Impaired [Member]

Impaired [Member]

Impaired [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Taken in Foreclosure [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Minimum [Member]

Minimum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

Maximum [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Minimum [Member]

Minimum [Member]

Minimum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

Maximum [Member]

Maximum [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Market Approach Valuation Technique [Member]

Acquisition Development And Construction [Member]

Commercial Loan [Member]

Commercial Real Estate [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Acquisition Development And Construction [Member]

Commercial Real Estate [Member]

Residential Mortgage [Member]

Mortgage Servicing Rights [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Fair Value, Measurements, Nonrecurring [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Acquisition Development And Construction [Member]

Commercial Loan [Member]

Commercial Real Estate [Member]

Acquisition Development And Construction [Member]

Commercial Loan [Member]

Commercial Real Estate [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Acquisition Development And Construction [Member]

Commercial Real Estate [Member]

Residential Mortgage [Member]

Mortgage Servicing Rights [Member]

Acquisition Development And Construction [Member]

Commercial Real Estate [Member]

Residential Mortgage [Member]

Mortgage Servicing Rights [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

speed

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

Significant Unobservable Inputs Level 3 [Member]

speed

speed

Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Loans, net

'

'

$4,150,709

$2,422,824

$4,897

$6,013

$2,254

$311

$2,332

'

'

'

'

'

'

$2,082

$3,619

$1,865

'

'

'

'

'

'

'

'

'

Fair Value Inputs, Comparability Adjustments

'

'

'

'

'

'

'

'

'

10.00%

9.00%

15.00%

30.00%

19.00%

36.00%

'

'

'

'

25.00%

20.00%

16.00%

9.30%

70.00%

37.00%

59.00%

12.80%

Fair Value Weighted Average

'

'

'

'

'

'

0.135

0.144

0.22

'

'

'

'

'

'

0.302

0.248

0.216

'

'

'

'

'

'

'

'

'

Prepayment speed

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100

'

'

'

968

Weighted average prepayment speed

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

224

'

'

'

'

'

'

'

'

Servicing Asset at Fair Value, Amount

$1,863

$1,978

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$1,863

'

'

'

'

'

'

'

'

Fair_Value_Measurements_Detail4

Fair Value Measurements (Details 5) (USD $)	Dec. 31, 2013	Sep. 30, 2013
Financial assets:	'	'
Securities available for sale	$1,153,313,000	$954,393,000
Securities held to maturity	479,977,000	250,896,000
Financial liabilities:	'	'
Senior Notes	-98,123,000	-98,033,000
Subordinated debentures	-26,519,000	0
Level 1 [Member]	'	'
Financial assets:	'	'
Cash and due from banks	152,662,000	113,090,000
Securities available for sale	0	0
Securities held to maturity	0	0
Loans, net	0	0
Loans held for sale	0	0
Accrued interest receivable on securities	0	0
Accrued interest receivable on loans	0	0
Interest rate caps and swaps	0	0
Financial liabilities:	'	'
Non-maturity deposits	-4,270,379,000	-2,694,166,000
Certificates of deposit	0	0
FHLB and other borrowings	0	0
Other Borrowings	0	'
Senior Notes	0	0
Subordinated debentures	0	'
Mortgage escrow funds	0	0
Accrued interest payable on deposits including escrow	0	0
Accrued interest payable on borrowings	0	0
Interest rate swaps	0	0
Level 2 [Member]	'	'
Financial assets:	'	'
Cash and due from banks	0	0
Securities available for sale	1,149,957,000	950,780,000
Securities held to maturity	479,977,000	250,896,000
Loans, net	0	0
Loans held for sale	24,483,000	1,011,000
Accrued interest receivable on securities	7,271,000	4,892,000
Accrued interest receivable on loans	0	0
Interest rate caps and swaps	621,000	997,000
Financial liabilities:	'	'
Non-maturity deposits	0	0
Certificates of deposit	-650,061,000	-268,088,000
FHLB and other borrowings	-513,438,000	-488,369,000
Other Borrowings	-82,106,000	'
Senior Notes	-101,087,000	-98,142,000
Subordinated debentures	-26,338,000	'
Mortgage escrow funds	-13,457,000	-12,644,000
Accrued interest payable on deposits including escrow	-3,205,000	-1,480,000
Accrued interest payable on borrowings	-1,480,000	'
Interest rate swaps	-621,000	-997,000
Level 3 [Member]	'	'
Financial assets:	'	'
Cash and due from banks	0	0
Securities available for sale	3,356,000	3,613,000
Securities held to maturity	0	0
Loans, net	4,150,709,000	2,422,824,000
Loans held for sale	0	0
Accrued interest receivable on securities	0	0
Accrued interest receivable on loans	8,785,000	'
Interest rate caps and swaps	0	0
Financial liabilities:	'	'
Non-maturity deposits	0	0
Certificates of deposit	0	0
FHLB and other borrowings	0	0
Other Borrowings	0	'
Senior Notes	0	0
Subordinated debentures	0	'
Mortgage escrow funds	0	0
Accrued interest payable on deposits including escrow	0	0
Accrued interest payable on borrowings	0	0
Interest rate swaps	0	0
Carrying Amount [Member]	'	'
Financial assets:	'	'
Cash and due from banks	152,662,000	113,090,000
Securities available for sale	1,153,313,000	954,393,000
Securities held to maturity	486,902,000	253,999,000
Loans, net	4,096,529,000	2,384,021,000
Loans held for sale	24,483,000	1,011,000
Accrued interest receivable on securities	7,271,000	4,892,000
Accrued interest receivable on loans	8,785,000	6,805,000
FHLB stock and Federal Reserve Bank stock	43,326,000	24,312,000
Interest rate caps and swaps	621,000	997,000
Financial liabilities:	'	'
Non-maturity deposits	-4,270,379,000	-2,694,166,000
Certificates of deposit	-650,185,000	-268,128,000
FHLB and other borrowings	-489,787,000	-462,953,000
Other Borrowings	-81,841,000	'
Senior Notes	-98,123,000	-98,033,000
Subordinated debentures	-26,519,000	'
Mortgage escrow funds	-13,460,000	-12,646,000
Accrued interest payable on deposits including escrow	-3,205,000	-1,480,000
Accrued interest payable on borrowings	-1,480,000	-1,525,000
Interest rate swaps	($621,000)	($997,000)

Fair_Value_Measurements_Fair_v1

Fair Value Measurements Fair value measurements (Details Textual) (USD $)	3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2013
Fair Value Measurements (Textual) [Abstract]	'	'	'
Available-for-sale Securities, Amortized Cost Basis	$1,173,054,000	'	$973,709,000
Fair value	1,153,313,000	'	954,393,000
Weighted average coupon rate of investment securities	2.76%	'	'
Weighted average life of investment securities	'3 years 4 months 13 days	'	'
Fair value inputs prepayment period	'15 years 4 months 21 days	'	'
Fair Value Inputs, Probability of Default	3.64%	'	'
Changes in fair value recognized on provisions on loans held by the Company	56,000	1,815,000	'
Mortgage servicing rights	1,863,000	1,978,000	'
Other real estate owned	11,751,000	'	6,022,000
Changes in fair value recognized through income for foreclosed assets held by the Company	224,000	158,000	'
Fair Value, Measurements, Recurring [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Loans	33,511,000	'	35,230,000
Fair Value, Measurements, Nonrecurring [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Other real estate owned	7,566,000	'	6,022
Collateralized Mortgage Obligations [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Impaired Available For Sale Securities Amortized Cost	3,075,000	'	'
Temporary impairment charge for the securities due to Temporary losses to securities	0	14,000	'
Accumulated Other Comprehensive Income (Loss), Other than Temporary Impairment, Not Credit Loss, Net of Tax, Debt Securities	136,000	'	'
Number Of Other Than Temporarily Impaired Securities	2	'	'
Impaired Available For Sale Securities Fair Value	3,073,000	'	'
Level 3 [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Fair value	3,356,000	'	3,613,000
Loans	4,150,709,000	'	2,422,824,000
Level 3 [Member] | Fair Value, Measurements, Recurring [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Fair value	3,356,000	'	3,613,000
Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Loans	4,897,000	'	6,013,000
Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] | Real estate-commercial mortgage [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Loans	2,332,000	'	'
Collateralized Mortgage Obligations [Member] | Level 3 [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Available-for-sale Securities, Amortized Cost Basis	3,362,000	'	'
Fair value	3,356,000	'	'
Mortgage-backed securities-residential [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Available-for-sale Securities, Amortized Cost Basis	502,377,000	'	454,173,000
Fair value	497,261,000	'	449,183,000
Mortgage-backed securities-residential [Member] | Collateralized Mortgage Obligations [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Available-for-sale Securities, Amortized Cost Basis	141,677,000	'	169,336,000
Fair value	139,265,000	'	166,654,000
Commercial Real Estate [Member] | Taken in Foreclosure [Member] | Market Approach Valuation Technique [Member] | Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member]	'	'	'
Fair Value Measurements (Textual) [Abstract]	'	'	'
Loans	$3,619,000	'	'

Comprehensive_income_Comprehen1

Comprehensive income Comprehensive income (Details) (USD $)

3 Months Ended

3 Months Ended

3 Months Ended

In Thousands, unless otherwise specified

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2012

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2012

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2011

Accumulated Net Unrealized Investment Gain (Loss) [Member]

Accumulated Other Comprehensive Income (Loss) [Member]

Accumulated Net Unrealized Investment Gain (Loss) [Member]

Accumulated Net Unrealized Investment Gain (Loss) [Member]

Accumulated Net Unrealized Investment Gain (Loss) [Member]

Accumulated Net Unrealized Investment Gain (Loss) [Member]

Unrealized gain(loss) for pension and other post-retirement obligations [Member]

Unrealized gain(loss) for pension and other post-retirement obligations [Member]

Unrealized gain(loss) for pension and other post-retirement obligations [Member]

Unrealized gain(loss) for pension and other post-retirement obligations [Member]

Reclassification out of Accumulated Other Comprehensive Income [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accumulated Other Comprehensive Income (Loss), Net of Tax

($19,465)

$4,665

($15,330)

$6,899

$12,547

'

($17,054)

'

($11,472)

$15,066

($2,411)

($7,882)

($3,858)

($8,167)

Other Comprehensive Income (Loss), before Reclassifications, Net of Tax

-6,013

-1,393

'

'

'

'

-6,013

-1,678

'

'

0

285

'

'

Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax

1,878

-841

'

'

'

'

431

-841

'

'

1,447

0

'

'

Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax

-5,582

-2,519

'

'

'

'

-5,582

'

'

'

'

'

'

'

Net gain on sale of securities

-645

1,416

'

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax

-645

'

'

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Tax

-214

'

'

'

'

'

'

'

'

'

'

'

'

'

other comprehensive income(loss) available for sale securities net of tax relass adjustments

431

'

'

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, before Tax

2,336

'

'

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax

889

-195

'

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax

-1,447

-285

'

'

'

'

'

'

'

'

1,447

'

'

'

Other Comprehensive Income (Loss), Net of Tax

($4,135)

($2,234)

'

'

'

($4,135)

'

($2,519)

'

'

'

($285)

'

'