Anticipated payment to the postretirement plans participants for the next fiscal year for non-qualified trusts.

No definition available.

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- Definition

Defined Benefit Plan, Lump-sum Payment Recognized as Settlement Gain (Loss), Minimum Threshold

+ References

No definition available.

+ Details

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- Definition

Reflects the upper limit on age eligibility, post early retirement, when medical insurance is available to retiree.

+ References

No definition available.

+ Details

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- Definition

The amortization period for transition obligation not yet in postretirement benefit costs.

+ References

No definition available.

+ Details

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- Definition

Net increase or decrease in the plan benefit obligation during the reporting period.

+ 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 (a)

-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ Details

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- 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 Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ Details

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Balance Type:	debit
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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.

+ Details

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS - Narrative (Details) - Jun. 30, 2015 - USD ($)	Total	Total
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Extent of lump-sum payments recognized, percentage		100.00%
Net reduction in projected obligation	$ 7,400,000
Medical insurance available until age is reached after early retirement		65 years
Amortization period for transition obligation excluded from postretirement benefit cost (in years)		20 years
Pension Plans \| Laclede Gas
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions made by employer		$ 27,200,000
Pension Plans \| Missouri Gas Energy (MGE)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Anticipated contributions to pension plans for qualified trust		0
Pension Plans \| Alagasco
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions made by employer		0
Anticipated contributions to pension plans for qualified trust		0
Nonqualified Pension Plans \| Laclede Gas
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions made by employer		300,000
Nonqualified Pension Plans \| Missouri Gas Energy (MGE)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Anticipated contributions to pension plans for qualified trust		200,000
Postretirement Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Anticipated contributions to pension plans for qualified trust		9,200,000
Anticipated payment directly to participants in postretirement plan		200,000
Postretirement Plans \| Missouri Gas Energy (MGE)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions made by employer		$ 8,900,000