Represents the maximum percentage of investments in any one company.

No definition available.

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- Definition

Estimated net actuarial loss that will be recognized as a component of net periodic cost in the next year

+ References

No definition available.

+ Details

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- Definition

Estimated prior service cost that will be recognized as a component in net periodic cost in the next year

+ References

No definition available.

+ Details

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Period Type:	duration

- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph g

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Benefit Plans (Details 3) (USD $)	12 Months Ended
Benefit Plans (Details 3) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Benefit Plans
Net actuarial loss that will be recognized as components of net periodic cost in 2013	$ 3,900,000
Prior service cost that will be recognized as components of net periodic cost in 2013	213,000
Accumulated benefit obligation	260,100,000	244,200,000
Pension Benefits
Benefit Plans
Contribution to Astoria Federal Pension Plan	34,194,000	17,606,000
Astoria Federal \| Pension Benefits
Benefit Plans
Contribution to Astoria Federal Pension Plan	19,100,000
Estimated Contribution to Astoria Federal Pension Plan in 2013	$ 5,000,000
Astoria Federal \| Pension Benefits \| Equity securities
Benefit Plans
Maximum securities (as a percent)	80.00%
Equity securities percentage in any one company	10.00%
Astoria Federal \| Pension Benefits \| Equity securities \| Large Cap Equity Securities
Benefit Plans
Maximum securities (as a percent)	50.00%
Astoria Federal \| Pension Benefits \| Equity securities \| Mid Cap Equity Securities
Benefit Plans
Maximum securities (as a percent)	20.00%
Astoria Federal \| Pension Benefits \| Equity securities \| Small Cap Equity Securities
Benefit Plans
Maximum securities (as a percent)	20.00%
Astoria Federal \| Pension Benefits \| Equity securities \| International Equity Securities
Benefit Plans
Maximum securities (as a percent)	10.00%
Astoria Federal \| Pension Benefits \| Astoria Financial Corporation common stock
Benefit Plans
Maximum securities (as a percent)	15.00%
Astoria Federal \| Pension Benefits \| Astoria Financial Corporation common stock \| Maximum
Benefit Plans
Equity securities percentage in total plan assets	10.00%
Astoria Federal \| Pension Benefits \| Industry concentration
Benefit Plans
Maximum securities (as a percent)	30.00%
Astoria Federal \| Pension Benefits \| Equities that mirror the S&P 500
Benefit Plans
Maximum securities (as a percent)	50.00%
Astoria Federal \| Pension Benefits \| Debt securities
Benefit Plans
Maximum securities (as a percent)	50.00%
Astoria Federal \| Pension Benefits \| Liquidity funds
Benefit Plans
Maximum securities (as a percent)	25.00%