Note 3 - Loans and Allowance for Loan Losses (Details Textual) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($)	Dec. 31, 2017
TDR Loans Transferred to Non-performing, Number of Contracts	1	0
Servicing Mortgage Loans [Member]
Servicing Asset, Loans Serviced, Amount	$ 36.5
Servicing SBA Loans [Member]
Servicing Asset, Loans Serviced, Amount	$ 18.4
Multi-family Residential Property and Commercial Real Estate and Commerical Business and Other Loans [Member]
Loan Origination, Underwriting Requirements, Minimum Debt Service Coverage	125.00%
Loan Origination, Value, Maximum Percentage	75.00%
Multi-family Residential Property and Commercial Real Estate and Commerical Business and Other Loans [Member] \| Gross Loans [Member] \| Credit Concentration Risk [Member]
Concentration Risk, Percentage	84.70%	84.80%
Commercial Real Estate Portfolio Segment [Member]
Number of Real Estate Classified as Troubled Debt Restructuring Sold	1
Financing Receivable, Modification, Sold During Period	$ 1.8
Loss on Sale of Real Estate Classified as Troubled Debt Restructuring	$ 0.3
Taxi Medallion Portfolio Segment [Member]
Financing Receivable, Modifications, Number of Contracts, Paid Off	4
Financing Receivable, Modifications, Amount Paid Off	$ 1.4
Number of Assets Foreclosed on During the Period	1
Taxi Medallion Portfolio Segment [Member] \| Other Assets [Member]
Other Repossessed Assets	$ 0.1

Represents the amount of modified TDR sold during the period.

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- Definition

Amount of financing receivables paid off that have been modified by troubled debt restructurings.

+ References

No definition available.

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Number of financing receivables paid off that have been modified by troubled debt restructurings.

+ References

No definition available.

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- Definition

The minimum debt service coverage percentage required to meet the company's underwriting requirements for loan origination.

+ References

No definition available.

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- Definition

The maximum percentage of appraised value or purchase price of property of which the company will originate loans.

+ References

No definition available.

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- Definition

Represents the amount of loss on sale of real estate classified as troubled debt restructuring (TDR).

+ References

No definition available.

+ Details

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- Definition

Represents number of assets foreclosed on during the period.

+ References

No definition available.

+ Details

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- Definition

Represents number of real estate which is classified as troubled debt restructuring (TDR) sold during the period.

+ References

No definition available.

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- Definition

Aggregate amount of loans serviced for others as part of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

+ References

No definition available.

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- Definition

Number of TDR loans transferred to non-performing loans during the period.

+ References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
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- Definition

Carrying amount as of the balance sheet date of assets other than real property that were received in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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