Note 11 - Carrying Amounts and Estimated Fair Values of Selected Financial Instruments as Well as Assumptions Used in Estimating Fair Value (Details) - USD ($)	Jun. 30, 2016	Dec. 31, 2015
Reported Value Measurement [Member] | Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	$ 16,201,000	$ 4,314,000
Interest Rate Swaps, Net Amount		48,000
Reported Value Measurement [Member]
Cash and due from banks	50,165,000	42,363,000
Other securities, fair value option	28,410,000	6,180,000
Mortgage-backed securities	580,500,000	668,740,000
Other securities	368,611,000	324,657,000
Loans	4,696,279,000	4,387,979,000
FHLB-NY stock	67,195,000	56,066,000
Total assets	5,791,160,000	5,486,033,000
Deposits	3,941,224,000	3,892,547,000
Borrowings	1,444,751,000	1,271,676,000
Total liabilities	5,402,176,000	5,168,537,000
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member] | Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount
Interest Rate Swaps, Net Amount
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and due from banks	50,165,000	42,363,000
Other securities, fair value option
Mortgage-backed securities
Other securities
Loans
FHLB-NY stock
Total assets	50,165,000	42,363,000
Deposits	2,529,674,000	2,489,245,000
Borrowings
Total liabilities	2,529,674,000	2,489,245,000
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	16,201,000	4,314,000
Interest Rate Swaps, Net Amount		48,000
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and due from banks
Other securities, fair value option
Mortgage-backed securities	580,500,000	668,740,000
Other securities	361,444,000	317,445,000
Loans
FHLB-NY stock	67,195,000	56,066,000
Total assets	1,009,139,000	1,042,299,000
Deposits	1,433,197,000	1,413,643,000
Borrowings	1,431,052,000	1,250,928,000
Total liabilities	2,880,450,000	2,668,885,000
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member] | Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount
Interest Rate Swaps, Net Amount
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and due from banks
Other securities, fair value option	28,410,000	6,180,000
Mortgage-backed securities
Other securities	7,167,000	7,212,000
Loans	4,740,014,000	4,434,079,000
FHLB-NY stock
Total assets	4,775,591,000	4,447,471,000
Deposits
Borrowings	27,485,000	29,018,000
Total liabilities	27,485,000	29,018,000
Estimate of Fair Value Measurement [Member] | Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	16,201,000	4,314,000
Interest Rate Swaps, Net Amount		48,000
Estimate of Fair Value Measurement [Member]
Cash and due from banks	50,165,000	42,363,000
Other securities, fair value option	28,410,000	6,180,000
Mortgage-backed securities	580,500,000	668,740,000
Other securities	368,611,000	324,657,000
Loans	4,740,014,000	4,434,079,000
FHLB-NY stock	67,195,000	56,066,000
Total assets	5,834,895,000	5,532,133,000
Deposits	3,962,871,000	3,902,888,000
Borrowings	1,458,537,000	1,279,946,000
Total liabilities	5,437,609,000	5,187,148,000
Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount
Interest Rate Swaps, Net Amount		0
Other securities, fair value option	28,410,000	6,180,000
Mortgage-backed securities	$ 580,500,000	$ 668,740,000