Note 15 - Commitments and Contingencies (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended			2 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Jul. 31, 2007 Capital Securities [Member] Flushing Financial's Capital Trusts [Member]	Dec. 31, 2012 Home Equity Line of Credit [Member]	Dec. 31, 2012 Letter of Credit Pledged as Collateral [Member]	Dec. 31, 2011 Letter of Credit Pledged as Collateral [Member]	Dec. 31, 2012 Mortgage Loans on Real Estate [Member]
Loans and Leases Receivable, Commitments, Credit					$ 135.8			$ 46.5
Loans and Leases Receivable, Commitments, Fixed Rates	22.0
Loans and Leases Receivable, Commitments, Weighted Average Fixed Rate of Interest	5.33%
Loans and Leases Receivable, Commitments, Variable Rates	160.3
Loans and Leases Receivable, Commitments, Variable Rates, Weighted Average Rate	3.38%
Line of Credit, Maturity, Max	18 months				10 years
Deposit Liabilities, Collateral Issued, Financial Instruments						414.6	392.3
Proceeds from Issuance of Debt				61.9
Operating Leases, Rent Expense	$ 3.7	$ 3.8	$ 3.2