REGULATORY MATTERS (Tables)

3 Months Ended

Dec. 31, 2017

Regulated Operations [Abstract]

Schedule of regulatory assets

The following regulatory assets and regulatory liabilities, including purchased gas adjustments, were reflected in the balance sheets of the Company, Spire Missouri and Spire Alabama as of December 31, 2017, September 30, 2017, and December 31, 2016.

	December 31,		September 30,		December 31,
Spire	2017		2017		2016
Regulatory Assets:
Current:
Pension and postretirement benefit costs	$	43.0	$	42.2	$	63.2
Unamortized purchased gas adjustments	77.9		102.6		52.2
Other	28.4		30.7		19.1
Total Current Regulatory Assets	149.3		175.5		134.5
Noncurrent:
Future income taxes due from customers	113.1		170.5		155.5
Pension and postretirement benefit costs	394.8		404.7		439.2
Cost of removal	123.9		123.3		131.6
Unamortized purchased gas adjustments	—		9.9		4.7
Energy efficiency	30.0		29.0		26.0
Other	54.8		53.7		29.4
Total Noncurrent Regulatory Assets	716.6		791.1		786.4
Total Regulatory Assets	$	865.9	$	966.6	$	920.9
Regulatory Liabilities:
Current:
Rate Stabilization and Equalization (RSE) adjustment	$	1.0	$	1.4	$	3.8
Unbilled service margin	—		—		22.0
Refundable negative salvage	7.9		8.2		9.0
Unamortized purchased gas adjustments	1.0		1.0		1.4
Other	11.6		12.0		8.0
Total Current Regulatory Liabilities	21.5		22.6		44.2
Noncurrent:
Deferred taxes due to customers	177.4		—		—
Pension and postretirement benefit costs	31.5		32.2		28.3
Refundable negative salvage	3.8		4.1		8.9
Accrued cost of removal	81.7		83.8		74.7
Other	40.7		37.1		20.2
Total Noncurrent Regulatory Liabilities	335.1		157.2		132.1
Total Regulatory Liabilities	$	356.6	$	179.8	$	176.3

	December 31,		September 30,		December 31,
Spire Missouri	2017		2017		2016
Regulatory Assets:
Current:
Pension and postretirement benefit costs	$	34.9	$	34.9	$	56.3
Unamortized purchased gas adjustments	38.5		57.4		33.8
Other	3.3		3.3		3.4
Total Current Regulatory Assets	76.7		95.6		93.5
Noncurrent:
Future income taxes due from customers	113.1		170.5		155.5
Pension and postretirement benefit costs	315.8		322.7		333.3
Unamortized purchased gas adjustments	—		9.9		4.7
Energy efficiency	30.0		29.0		26.0
Other	25.2		25.7		23.9
Total Noncurrent Regulatory Assets	484.1		557.8		543.4
Total Regulatory Assets	$	560.8	$	653.4	$	636.9
Regulatory Liabilities:
Current:
Other	$	2.7	$	2.7	$	2.7
Total Current Regulatory Liabilities	2.7		2.7		2.7
Noncurrent:
Deferred taxes due to customers	159.2		—		—
Accrued cost of removal	52.0		54.5		54.8
Other	30.0		26.7		12.5
Total Noncurrent Regulatory Liabilities	241.2		81.2		67.3
Total Regulatory Liabilities	$	243.9	$	83.9	$	70.0

	December 31,		September 30,		December 31,
Spire Alabama	2017		2017		2016
Regulatory Assets:
Current:
Pension and postretirement benefit costs	$	7.2	$	7.2	$	6.8
Unamortized purchased gas adjustments	39.4		45.2		17.1
Other	11.4		12.2		7.6
Total Current Regulatory Assets	58.0		64.6		31.5
Noncurrent:
Pension and postretirement benefit costs	70.8		72.6		96.8
Cost of removal	123.9		123.3		131.6
Other	2.7		1.1		1.1
Total Noncurrent Regulatory Assets	197.4		197.0		229.5
Total Regulatory Assets	$	255.4	$	261.6	$	261.0
Regulatory Liabilities:
Current:
RSE adjustment	$	1.0	$	1.4	$	3.8
Unbilled service margin	—		—		22.0
Refundable negative salvage	7.9		8.2		9.0
Other	2.4		2.4		2.6
Total Current Regulatory Liabilities	11.3		12.0		37.4
Noncurrent:
Pension and postretirement benefit costs	31.5		32.2		28.3
Refundable negative salvage	3.9		4.1		8.9
Other	3.6		3.3		3.4
Total Noncurrent Regulatory Liabilities	39.0		39.6		40.6
Total Regulatory Liabilities	$	50.3	$	51.6	$	78.0

A portion of the Company’s and Spire Missouri’s regulatory assets are not earning a return, as shown in the table below:

	Spire						Spire Missouri
	December 31,		September 30,		December 31,		December 31,		September 30,		December 31,
	2017		2017		2016		2017		2017		2016
Future income taxes due from customers	$	113.1	$	170.5	$	155.5	$	113.1	$	170.5	$	155.5
Pension and postretirement benefit costs	193.8		198.5		231.4		193.8		198.5		231.4
Other	11.2		11.3		12.2		11.2		11.3		12.2
Total Regulatory Assets Not Earning a Return	$	318.1	$	380.3	$	399.1	$	318.1	$	380.3	$	399.1

Schedule of regulatory liabilities

The following regulatory assets and regulatory liabilities, including purchased gas adjustments, were reflected in the balance sheets of the Company, Spire Missouri and Spire Alabama as of December 31, 2017, September 30, 2017, and December 31, 2016.

	December 31,		September 30,		December 31,
Spire	2017		2017		2016
Regulatory Assets:
Current:
Pension and postretirement benefit costs	$	43.0	$	42.2	$	63.2
Unamortized purchased gas adjustments	77.9		102.6		52.2
Other	28.4		30.7		19.1
Total Current Regulatory Assets	149.3		175.5		134.5
Noncurrent:
Future income taxes due from customers	113.1		170.5		155.5
Pension and postretirement benefit costs	394.8		404.7		439.2
Cost of removal	123.9		123.3		131.6
Unamortized purchased gas adjustments	—		9.9		4.7
Energy efficiency	30.0		29.0		26.0
Other	54.8		53.7		29.4
Total Noncurrent Regulatory Assets	716.6		791.1		786.4
Total Regulatory Assets	$	865.9	$	966.6	$	920.9
Regulatory Liabilities:
Current:
Rate Stabilization and Equalization (RSE) adjustment	$	1.0	$	1.4	$	3.8
Unbilled service margin	—		—		22.0
Refundable negative salvage	7.9		8.2		9.0
Unamortized purchased gas adjustments	1.0		1.0		1.4
Other	11.6		12.0		8.0
Total Current Regulatory Liabilities	21.5		22.6		44.2
Noncurrent:
Deferred taxes due to customers	177.4		—		—
Pension and postretirement benefit costs	31.5		32.2		28.3
Refundable negative salvage	3.8		4.1		8.9
Accrued cost of removal	81.7		83.8		74.7
Other	40.7		37.1		20.2
Total Noncurrent Regulatory Liabilities	335.1		157.2		132.1
Total Regulatory Liabilities	$	356.6	$	179.8	$	176.3

	December 31,		September 30,		December 31,
Spire Missouri	2017		2017		2016
Regulatory Assets:
Current:
Pension and postretirement benefit costs	$	34.9	$	34.9	$	56.3
Unamortized purchased gas adjustments	38.5		57.4		33.8
Other	3.3		3.3		3.4
Total Current Regulatory Assets	76.7		95.6		93.5
Noncurrent:
Future income taxes due from customers	113.1		170.5		155.5
Pension and postretirement benefit costs	315.8		322.7		333.3
Unamortized purchased gas adjustments	—		9.9		4.7
Energy efficiency	30.0		29.0		26.0
Other	25.2		25.7		23.9
Total Noncurrent Regulatory Assets	484.1		557.8		543.4
Total Regulatory Assets	$	560.8	$	653.4	$	636.9
Regulatory Liabilities:
Current:
Other	$	2.7	$	2.7	$	2.7
Total Current Regulatory Liabilities	2.7		2.7		2.7
Noncurrent:
Deferred taxes due to customers	159.2		—		—
Accrued cost of removal	52.0		54.5		54.8
Other	30.0		26.7		12.5
Total Noncurrent Regulatory Liabilities	241.2		81.2		67.3
Total Regulatory Liabilities	$	243.9	$	83.9	$	70.0

	December 31,		September 30,		December 31,
Spire Alabama	2017		2017		2016
Regulatory Assets:
Current:
Pension and postretirement benefit costs	$	7.2	$	7.2	$	6.8
Unamortized purchased gas adjustments	39.4		45.2		17.1
Other	11.4		12.2		7.6
Total Current Regulatory Assets	58.0		64.6		31.5
Noncurrent:
Pension and postretirement benefit costs	70.8		72.6		96.8
Cost of removal	123.9		123.3		131.6
Other	2.7		1.1		1.1
Total Noncurrent Regulatory Assets	197.4		197.0		229.5
Total Regulatory Assets	$	255.4	$	261.6	$	261.0
Regulatory Liabilities:
Current:
RSE adjustment	$	1.0	$	1.4	$	3.8
Unbilled service margin	—		—		22.0
Refundable negative salvage	7.9		8.2		9.0
Other	2.4		2.4		2.6
Total Current Regulatory Liabilities	11.3		12.0		37.4
Noncurrent:
Pension and postretirement benefit costs	31.5		32.2		28.3
Refundable negative salvage	3.9		4.1		8.9
Other	3.6		3.3		3.4
Total Noncurrent Regulatory Liabilities	39.0		39.6		40.6
Total Regulatory Liabilities	$	50.3	$	51.6	$	78.0