Threshold Period Past Due for Collection

No definition available.

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- Definition

For an unclassified balance sheet, the amount of fees and other revenue, excluding investment income receivable, earned but not yet received, which were recognized in conformity with revenue recognition criteria based on estimates or specific contractual terms.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Future cash outflow to pay for purchases of fixed assets that have occurred.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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Balance Type:	credit
Period Type:	duration

- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953401-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Cash inflow representing an adjustment to the purchase price of a previous acquisition.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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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Balance Type:	na
Period Type:	duration

- Details

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Balance Type:
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- Details

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- Details

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- Details

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Millions		6 Months Ended		12 Months Ended
	Sep. 12, 2016 USD ($)	Mar. 31, 2017 USD ($) reporting_unit	Mar. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)
Related Party Transaction [Line Items]
Number of operating segments \| reporting_unit		2
Proceeds from settlement for acquisition of EnergySouth		$ 3.8	$ 0.0
Accruals for capital expenditures		9.2	9.0	$ 21.6
Laclede Gas
Related Party Transaction [Line Items]
Accrued unbilled revenues		66.7	57.4	26.1
Accruals for capital expenditures		$ 3.3	5.3	14.8
Alagasco
Related Party Transaction [Line Items]
Threshold Period Past Due for Collection		90 days
Accrued unbilled revenues		$ 13.5	14.9	5.9
Accruals for capital expenditures		$ 5.3	3.7	6.8
Alagasco \| Financing Receivables, Equal to Greater than 90 Days Past Due
Related Party Transaction [Line Items]
Financing receivable, recorded investment, past due			$ 0.4	$ 0.4
EnergySouth
Related Party Transaction [Line Items]
Proceeds from settlement for acquisition of EnergySouth	$ 3.8