COMMITMENTS AND CONTINGENCIES (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Mar. 31, 2014 site	Sep. 30, 2005
Contingencies and Indemnifications [Abstract]
Minimum total payments required for natural gas contracts	$ 805
Number of former manufactured gas plant (MGP) sites in Missouri	3
Number of former manufactured gas plant (MGP) sites in Shrewsbury, Missouri	1
Number of former manufactured gas plant (MGP) sites in the City of St. Louis	2
Minimum cost estimate for a one-time contractual transfer of risk		5.8
Maximum cost estimate for a one-time contractual transfer of risk		$ 36.3

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The number of manufactured gas plant (MGP) sites in Missouri posing potential environmental liability at St Louis.

+ References

No definition available.

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The number of former manufactured gas plant (MGP) sites in Missouri posing potential environmental liability.

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The number of manufactured gas plant (MGP) sites in Missouri posing potential environmental liability at Shrewsbury.

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No definition available.

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The minimum amount the entity agreed to spend under the long-term purchase commitment.

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The estimated maximum amount of possible loss from the contingency.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

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The estimated minimum amount of possible loss from the contingency.

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