Benefit Plans (Details 10) (Astoria Bank, Pension benefits, USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Astoria Bank \| Pension benefits
Changes in the fair value of Level 3 assets
Fair value at beginning of year	$ 6,299	$ 7,177
Total net gain, realized and unrealized, included in change in net assets	191	21
Purchases	23,925	9,000
Sales	(18,557)	(9,899)
Fair value at end of year	$ 11,858	$ 6,299

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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