Note 10 - Fair Value of Financial Instruments - Carrying Amounts and Estimated Fair Values of Selected Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Other securities	$ 30,593	$ 35,408
Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	5,648	3,386
Interest rate swaps	2,601	3,386
Reported Value Measurement [Member]
Mortgage-backed securities	520,012	516,476
Other securities	317,693	344,905
Loans held for sale	30,565
Loans	5,045,680	4,835,693
FHLB-NY stock	66,630	59,173
Accrued interest receivable	21,439
Assets, Fair Value Disclosure	6,088,640	5,836,189
Deposits	4,254,803	4,205,631
Borrowings	1,425,779	1,266,563
Accrued interest payable	2,587
Financial and Nonfinancial Liabilities, Fair Value Disclosure	5,687,793	5,475,580
Cash and due from banks	48,539	35,857
Mortgage-backed securities	7,983
Other securities	24,451	37,735
Reported Value Measurement [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	5,648	6,350
Interest rate swaps	4,624	3,386
Estimate of Fair Value Measurement [Member]
Mortgage-backed securities	520,012	516,476
Other securities	317,693	344,905
Loans held for sale	30,565
Loans	5,021,555	4,814,840
FHLB-NY stock	66,630	59,173
Accrued interest receivable	21,439
Assets, Fair Value Disclosure	6,062,674	5,813,009
Deposits	4,256,788	4,213,714
Borrowings	1,422,040	1,255,283
Accrued interest payable	2,587
Financial and Nonfinancial Liabilities, Fair Value Disclosure	5,686,039	5,472,383
Cash and due from banks	48,539	35,857
Mortgage-backed securities	7,816
Other securities	22,777	35,408
Estimate of Fair Value Measurement [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	5,648	6,350
Interest rate swaps	4,624	3,386
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Mortgage-backed securities
Other securities
Loans held for sale
Loans
FHLB-NY stock
Accrued interest receivable
Assets, Fair Value Disclosure	48,539	35,857
Deposits	2,922,426	2,833,516
Borrowings
Accrued interest payable
Financial and Nonfinancial Liabilities, Fair Value Disclosure	2,922,426	2,833,516
Cash and due from banks	48,539	35,857
Mortgage-backed securities
Other securities
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount
Interest rate swaps
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Mortgage-backed securities	520,012	516,476
Other securities	310,249	337,544
Loans held for sale
Loans
FHLB-NY stock	66,630	59,173
Accrued interest receivable	21,439
Assets, Fair Value Disclosure	931,794	919,543
Deposits	1,334,362	1,380,198
Borrowings	1,386,903	1,221,324
Accrued interest payable	2,587
Financial and Nonfinancial Liabilities, Fair Value Disclosure	2,728,476	2,604,908
Cash and due from banks
Mortgage-backed securities	7,816
Other securities
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	5,648	6,350
Interest rate swaps	4,624	3,386
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Mortgage-backed securities
Other securities	7,444	7,361
Loans held for sale	30,565
Loans	5,021,555	4,814,840
FHLB-NY stock
Accrued interest receivable
Assets, Fair Value Disclosure	5,082,341	4,857,609
Deposits
Borrowings	35,137	33,959
Accrued interest payable
Financial and Nonfinancial Liabilities, Fair Value Disclosure	35,137	33,959
Cash and due from banks
Mortgage-backed securities
Other securities	22,777	35,408
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount
Interest rate swaps

Fair value portion of accrued interest payable.

No definition available.

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- Definition

Fair value portion of accrued interest receivable.

+ References

No definition available.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value pursuant to the fair value option by the entity. Additionally, this element may be used in connection with the fair value option disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities, except for mortgage-backed securities, neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References

No definition available.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Publisher FASB
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value of investments in debt securities classified as held-to-maturity.

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- Definition

Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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Fair value of financial and nonfinancial obligations.

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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- Definition

Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

+ References

No definition available.

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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as held-to-maturity.

+ References

No definition available.

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