LONG-TERM DEBT - Maturities of Long-term Debt (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014
Debt Instrument [Line Items]
Fixed-rate long-term debt amount	$ 1,603.6
Maturities on long-term debt [Abstract]
2015	0
2016	80.0
2017	250.0
2018	100.0
2019	175.0
Laclede Gas
Debt Instrument [Line Items]
Fixed-rate long-term debt amount	810.0
Maturities on long-term debt [Abstract]
2015	0
2016	0
2017	0
2018	100.0
2019	$ 50.0

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

+ Details

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- Definition

Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

No definition available.

+ Details

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