FAIR VALUE OF FINANCIAL INSTRUMENTS, Balance Sheet Groupings (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
ASSETS
Cash and due from banks	$ 194,702
Investment securities held to maturity (TRUPS)	0
Loans, net	0
Loans held for sale	0
Accrued Interest Receivable	0
Mortgage servicing rights (MSR)	0
Federal funds sold and other short term investments	59,999
Liabilities [Abstract]
Savings, money market and checking accounts	1,494,148
Certificates of Deposit (CDs)	0
Escrow and other deposits	111,066
REPO	0
FHLBNY advances	0
Trust preferred securities payable	0
Accrued Interest Payable	0
Commitments to extend credit	1,563
Fair Value, Inputs, Level 1 [Member]
Investment Securities Available For Sale [Abstract]
Agency Obligations	0	0
Domestic Equity Mutual Fund	3,563	3,162
Fixed Income Mutual Funds	1,141	1,082
International Equity Mutual Fund	335	315
Fair Value, Inputs, Level 2 [Member]
ASSETS
Cash and due from banks	0
Investment securities held to maturity (TRUPS)	0
Loans, net	5,500
Loans held for sale	387
Accrued Interest Receivable	543
Mortgage servicing rights (MSR)	1,631
Federal funds sold and other short term investments	0
Investment Securities Available For Sale [Abstract]
Agency Obligations	49,987	170,309
Domestic Equity Mutual Fund	0	0
Fixed Income Mutual Funds	0	0
International Equity Mutual Fund	0	0
Liabilities [Abstract]
Savings, money market and checking accounts	0
Certificates of Deposit (CDs)	942,077
Escrow and other deposits	0
REPO	179,631
FHLBNY advances	815,343
Trust preferred securities payable	68,560
Accrued Interest Payable	3,668
Commitments to extend credit	0
Fair Value, Inputs, Level 3 [Member]
ASSETS
Cash and due from banks	0
Investment securities held to maturity (TRUPS)	6,244
Loans, net	3,423,893
Loans held for sale	0
Accrued Interest Receivable	13,073
Mortgage servicing rights (MSR)	0
Federal funds sold and other short term investments	0
Investment Securities Available For Sale [Abstract]
Agency Obligations	0	0
Domestic Equity Mutual Fund	0	0
Fixed Income Mutual Funds	0	0
International Equity Mutual Fund	0	0
Liabilities [Abstract]
Savings, money market and checking accounts	0
Certificates of Deposit (CDs)	0
Escrow and other deposits	0
REPO	0
FHLBNY advances	0
Trust preferred securities payable	0
Accrued Interest Payable	0
Commitments to extend credit	0
Estimate of Fair Value, Fair Value Disclosure [Member]
ASSETS
Cash and due from banks	194,702	43,309
Investment securities held to maturity (TRUPS)	6,244	4,924
Loans, net	3,429,393	3,578,599
Loans held for sale	387	3,022
Accrued Interest Receivable	13,616	15,469
Mortgage servicing rights (MSR)	1,631	2,139
Federal funds sold and other short term investments	59,999	951
Liabilities [Abstract]
Savings, money market and checking accounts	1,494,148	1,366,150
Certificates of Deposit (CDs)	942,077	996,022
Escrow and other deposits	111,066	71,812
REPO	179,631	223,728
FHLBNY advances	815,343	991,117
Trust preferred securities payable	68,560	67,146
Accrued Interest Payable	3,668	3,997
Commitments to extend credit	1,563	917
Carrying (Reported) Amount, Fair Value Disclosure [Member]
ASSETS
Cash and due from banks	194,702	43,309
Investment securities held to maturity (TRUPS)	5,956	6,511
Loans, net	3,305,299	3,440,611
Loans held for sale	387	3,022
Accrued Interest Receivable	13,616	15,469
Mortgage servicing rights (MSR)	1,190	1,604
FHLBNY capital stock	41,636	49,489
Federal funds sold and other short term investments	59,999	951
Liabilities [Abstract]
Savings, money market and checking accounts	1,494,148	1,366,150
Certificates of Deposit (CDs)	925,018	977,551
Escrow and other deposits	111,066	71,812
REPO	155,000	195,000
FHLBNY advances	767,500	939,775
Trust preferred securities payable	70,680	70,680
Accrued Interest Payable	3,668	3,997
Commitments to extend credit	$ 1,563	$ 917

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