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Defined benefit plan pension plans with accumulated benefit obligations in excess of plan aggregate benefit obligation accumulated other comprehensive income net gains losses after tax.

No definition available.

Name:	sif_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAggregateBenefitObligationAccumulatedOtherComprehensiveIncomeNetGainsLossesAfterTax
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Defined benefit plans with benefit obligations in excess of plan assets aggregate assets accumulated other comprehensive income before tax.

No definition available.

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Defined benefit plans with benefit obligations in excess of plan assets aggregate benefit obligation accumulated other comprehensive income before tax.

No definition available.

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- References

No definition available.

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- References

No definition available.

Name:	us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract
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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.

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

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- References

No definition available.

Name:	us-gaap_DefinedBenefitPlanPlansWithBenefitObligationsInExcessOfPlanAssetsAbstract
Namespace Prefix:	us-gaap_
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If aggregate disclosures are presented, the aggregate benefit obligation for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

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

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Namespace Prefix:	us-gaap_
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If aggregate disclosures are presented, the aggregate fair value of plan assets for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.