FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)

6 Months Ended

Mar. 31, 2017

Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]

Fair value of financial instruments

The carrying amounts and estimated fair values of financial instruments not measured at fair value on a recurring basis are shown below and classified according to the fair value hierarchy. There were no such instruments classified as Level 3 (significant unobservable inputs) as of March 31, 2017, September 30, 2016, or March 31, 2016.

		Classification of Estimated Fair Value
Carrying Amount	Fair Value	Quoted Prices in Active Markets (Level 1)	Significant Observable Inputs (Level 2)

Spire

As of March 31, 2017
Cash and cash equivalents	$	19.6	$	19.6	$	19.6	$	—
Short-term debt	567.4		567.4		—		567.4
Long-term debt	1,925.3		1,993.9		—		1,993.9
As of September 30, 2016
Cash and cash equivalents	$	5.2	$	5.2	$	5.2	$	—
Short-term debt	398.7		398.7		—		398.7
Long-term debt, including current portion	1,820.7		2,257.1		—		2,257.1
As of March 31, 2016
Cash and cash equivalents	$	8.7	$	8.7	$	8.7	$	—
Short-term debt	253.6		253.6		—		253.6
Long-term debt	1,839.3		1,960.4		—		1,960.4

Laclede Gas

Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]

Fair value of financial instruments

As of March 31, 2017
Cash and cash equivalents	$	3.7	$	3.7	$	3.7	$	—
Short-term debt	282.2		282.2		—		282.2
Long-term debt	804.3		870.1		—		870.1
As of September 30, 2016
Cash and cash equivalents	$	2.1	$	2.1	$	2.1	$	—
Short-term debt	243.7		243.7		—		243.7
Long-term debt	804.1		900.4		—		900.4
As of March 31, 2016
Cash and cash equivalents	$	3.8	$	3.8	$	3.8	$	—
Short-term debt	169.6		169.6		—		169.6
Long-term debt	803.7		885.9		—		885.9

Alagasco

Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]

Fair value of financial instruments

					Classification of Estimated Fair Value
	Carrying Amount		Fair Value		Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)
As of March 31, 2017
Short-term debt	109.3		109.3		—		109.3
Long-term debt	$	247.7	$	261.6	$	—	$	261.6
As of September 30, 2016
Short-term debt	$	82.0	$	82.0	$	—	$	82.0
Long-term debt	247.6		275.5		—		275.5
As of March 31, 2016
Cash and cash equivalents	$	2.3	$	2.3	$	2.3	$	—
Short-term debt	41.0		41.0		—		41.0
Long-term debt	247.6		262.7		—		262.7