FHLBNY ADVANCES (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
FHLBNY advances	$ 1,173,725	$ 910,000
Average interest cost (in hundredths)	2.28%	2.89%	2.96%
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
2015	569,500
2016	151,000
2017	302,075
2018	77,100
2019	36,250
2020 and beyond	37,800
Total	1,173,725
Interest rate on outstanding advances (in hundredths)	1.74%	2.35%
FHLBNY Borrowing Capacity	$ 1,568,197dcom_FhlbnyBorrowingCapacity	$ 1,203,939dcom_FhlbnyBorrowingCapacity
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate of Amounts Due [Abstract]
2015	1.48%
2016	2.03%
2017	2.04%
2018	1.63%
2019	1.80%
2020 and beyond	2.46%
TOTAL	1.74%

The maximum borrowing capacity with the Federal Home Loan Bank of New York at period end.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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The calculated weighted average interest rate for Federal Home Loan Bank advances for the period ended as of the Balance Sheet date.

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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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States the weighted average interest rate applicable to the advances from the Federal Home Loan Bank outstanding as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(3)(a))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Industry Guide

-Number 3

-Section VII

-Subsection 1

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64702-112823

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due after five years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from four to five years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due within one year of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from one to two years of the Balance Sheet date.

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from three to four years of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.14)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher SEC

-Name Industry Guide

-Number 3

-Section VII

-Paragraph 3

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The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from two to three years of the Balance Sheet date.

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- Definition

Amount of advances from Federal Home Loan Bank (FHLBank) maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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