FAIR VALUE OF FINANCIAL INSTRUMENTS, Balance Sheet Groupings (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Estimate of Fair Value, Fair Value Disclosure [Member]
ASSETS
Cash and due from banks	$ 141,656	$ 79,076
Investment securities held to maturity (TRUPS)	5,528	6,195
Loans, net	3,649,573	3,610,065
Loans held for sale	469	560
Accrued Interest Receivable	12,897	13,518
Mortgage servicing rights (MSR)	1,336	1,511
FHLBNY capital stock	0	0
Liabilities [Abstract]
Savings, money market and checking accounts	1,721,985	1,587,454
Certificates of Deposit (CDs)	893,435	907,657
Escrow and other deposits	119,452	82,753
FHLBNY advances	786,765	885,774
Trust preferred securities payable	70,680	70,680
Accrued Interest Payable	2,820	2,827
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 1 [Member]
ASSETS
Cash and due from banks	141,656	79,076
Investment securities held to maturity (TRUPS)	0	0
Loans, net	0	0
Loans held for sale	0	0
Accrued Interest Receivable	21	0
Mortgage servicing rights (MSR)	0	0
FHLBNY capital stock	0	0
Liabilities [Abstract]
Savings, money market and checking accounts	1,721,985	1,587,454
Certificates of Deposit (CDs)	0	0
Escrow and other deposits	119,452	82,753
FHLBNY advances	0	0
Trust preferred securities payable	0	0
Accrued Interest Payable	0	0
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 2 [Member]
ASSETS
Cash and due from banks	0	0
Investment securities held to maturity (TRUPS)	0	0
Loans, net	0	0
Loans held for sale	469	560
Accrued Interest Receivable	251	359
Mortgage servicing rights (MSR)	1,336	1,511
FHLBNY capital stock	0	0
Liabilities [Abstract]
Savings, money market and checking accounts	0	0
Certificates of Deposit (CDs)	893,435	907,657
Escrow and other deposits	0	0
FHLBNY advances	786,765	885,774
Trust preferred securities payable	70,680	70,680
Accrued Interest Payable	2,820	2,827
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 3 [Member]
ASSETS
Cash and due from banks	0	0
Investment securities held to maturity (TRUPS)	5,528	6,195
Loans, net	3,649,573	3,609,505
Loans held for sale	0	0
Accrued Interest Receivable	12,625	13,159
Mortgage servicing rights (MSR)	0	0
FHLBNY capital stock	0	0
Liabilities [Abstract]
Savings, money market and checking accounts	0	0
Certificates of Deposit (CDs)	0	0
Escrow and other deposits	0	0
FHLBNY advances	0	0
Trust preferred securities payable	0	0
Accrued Interest Payable	0	0
Carrying (Reported) Amount, Fair Value Disclosure [Member]
ASSETS
Cash and due from banks	141,656	79,076
Investment securities held to maturity (TRUPS)	5,746	5,927
Loans, net	3,525,824	3,485,258
Loans held for sale	469	560
Accrued Interest Receivable	12,897	13,518
Mortgage servicing rights (MSR)	990	1,115
FHLBNY capital stock	40,736	45,011
Liabilities [Abstract]
Savings, money market and checking accounts	1,721,985	1,587,454
Certificates of Deposit (CDs)	879,330	891,975
Escrow and other deposits	119,452	82,753
FHLBNY advances	747,500	842,500
Trust preferred securities payable	70,680	70,680
Accrued Interest Payable	$ 2,820	$ 2,528