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

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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.

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- References

No definition available.

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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=58740216&loc=d3e1928-114920

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- Definition

If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=58242635&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2417-114920

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- Definition

If aggregate disclosures are presented, the aggregate projected benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2417-114920

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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-URI http://asc.fasb.org/extlink&oid=58242635&loc=d3e4179-114921

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- Definition

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

+ 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)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- 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=58740216&loc=d3e2446-114920

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Benefit Plans - Pension Plans and Other Postretirement Benefits (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Net actuarial loss	$ 2,500
Prior service cost	190
Accumulated benefit obligation	252,600	$ 252,400
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Projected benefit obligation for unfunded plans	14,600	14,400
Accumulated benefit obligation for unfunded plans	$ 14,600	$ 14,400
Equity securities \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	80.00%
Debt securities \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	50.00%
Liquidity funds \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	25.00%
Any one company \| Equity securities \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	10.00%
Any one industry \| Equity securities \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	30.00%
Funds that mirror the S&P 500 \| Equity securities \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	50.00%
Large-cap equity securities \| Equity securities \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	50.00%
Mid-cap equity securities \| Equity securities \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	20.00%
Small-cap equity securities \| Equity securities \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	20.00%
International equities \| Equity securities \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	10.00%
Astoria Financial Corporation common stock \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum asset mix within various insurance company pooled separate accounts and trust company trust funds (as a percent)	15.00%
Maximum \| Astoria Financial Corporation common stock \| Astoria Bank \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum acquisition of Astoria Financial Corporation common stock (as a percent)	10.00%