Number Of Former Manufactured Gas Plant (MGP) Sites Enrolled In BVCP

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Number Of Incident Fatalities

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No definition available.

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- Definition

Site Contingency, Number of Former Manufactured Gas Distribution

+ References

No definition available.

+ Details

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- Definition

Site Contingency, Number of Former Manufactured Gas Plant

+ References

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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

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- Definition

Number of claims settled.

+ References

No definition available.

+ Details

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- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

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- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

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- Definition

Number of pending claims pertaining to a loss contingency.

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COMMITMENTS AND CONTINGENCIES - Contingencies (Details)		9 Months Ended	57 Months Ended	63 Months Ended
COMMITMENTS AND CONTINGENCIES - Contingencies (Details)	Dec. 17, 2013 fatality	Jun. 30, 2017 plaintiff lawsuit site	Dec. 31, 2016 lawsuit	Jun. 30, 2017 lawsuit site	Sep. 30, 2014 site
Laclede Gas
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP) sites in Missouri		4		4
Number of former manufactured gas plant (MGP) sites enrolled in BVCP		2		2
Alagasco
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP)		9		9
Number of former manufactured gas distribution		5		5
Number of incident fatalities \| fatality	1
Mobile Gas Service Corporation [Member]
Loss Contingencies [Line Items]
Number of lawsuits filed \| lawsuit			14
Number of lawsuits settled \| lawsuit				11
Number of lawsuits pending \| lawsuit		3		3
Previous Ownership \| Laclede Gas
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP)					19
Previous Ownership \| Missouri Gas Energy (MGE)
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP)		7		7
Previous Ownership \| Mobile Gas Service Corporation [Member]
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP)		1		1
Current Ownership \| Alagasco
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP)		4		4
Number of former manufactured gas distribution		1		1
Pending Litigation [Member] \| Mobile Gas Service Corporation [Member]
Loss Contingencies [Line Items]
Number of plaintiffs \| plaintiff		270
Shrewsbury, Missouri \| Laclede Gas
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP) sites in Missouri		1		1
St. Louis, Missouri \| Laclede Gas
Loss Contingencies [Line Items]
Number of former manufactured gas plant (MGP) sites in Missouri		3		3