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

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Site Contingency, Number of Former Manufactured Gas Distribution

+ References

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Site Contingency, Number of Former Manufactured Gas Plant

+ References

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- Definition

Site Contingency, Number of Residents Contaminated

+ References

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The estimated maximum amount of possible loss from the contingency.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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The estimated minimum amount of possible loss from the contingency.

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COMMITMENTS AND CONTINGENCIES - Contingencies (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014 site	Aug. 30, 2014	Dec. 31, 2013 Resident
Loss Contingencies [Line Items]
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		$ 8.1
Maximum cost estimate for a one-time contractual transfer of risk		$ 39.3
Alagasco
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP)	9
Number of former manufactured gas distribution	5
Previous Ownership \| Missouri Gas Energy (MGE)
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP)	7
Previous Ownership \| Laclede Gas
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP)	19
Current Ownership \| Alagasco
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP)	4
Number of former manufactured gas distribution	1
Removal Action, Phase I \| 35th Avenue Superfund Site
Loss Contingencies [Line Items]
Number of residents at high levels of contamination			50
Removal Action, Phase II \| 35th Avenue Superfund Site
Loss Contingencies [Line Items]
Number of residents at high levels of contamination		30