Information by Operating Segment (Tables)

12 Months Ended

Sep. 30, 2019

Segment Reporting [Abstract]

Schedule of Operating Segment Information

2019	Gas Utility		Gas Marketing		Other			Eliminations			Consolidated
Revenues from external customers	$	1,859.2	$	83.7	$	9.5		$	—		$	1,952.4
Intersegment revenues		1.6		—		12.0			(13.6	)		—
Total Operating Revenues		1,860.8		83.7		21.5			(13.6	)		1,952.4
Operating Expenses
Gas Utility
Natural and propane gas		794.6		—		—			(96.4	)		698.2
Other operation and maintenance		441.7		—		—			(9.4	)		432.3
Depreciation and amortization		179.4		—		—			—			179.4
Taxes, other than income taxes		151.7		—		—			—			151.7
Total Gas Utility Operating Expenses		1,567.4		—		—			(105.8	)		1,461.6
Gas Marketing and Other *		—		60.5		35.8			92.2			188.5
Total Operating Expenses		1,567.4		60.5		35.8			(13.6	)		1,650.1
Operating Income (Loss)	$	293.4	$	23.2	$	(14.3	)	$	—		$	302.3
Net Economic Earnings (Loss)	$	199.8	$	19.4	$	(24.1	)	$	—		$	195.1
Capital Expenditures	$	565.4	$	3.1	$	254.8		$	—		$	823.3

2018	Gas Utility		Gas Marketing		Other			Eliminations			Consolidated
Revenues from external customers	$	1,888.0	$	71.6	$	5.4		$	—		$	1,965.0
Intersegment revenues		0.4		—		11.1			(11.5	)		—
Total Operating Revenues		1,888.4		71.6		16.5			(11.5	)		1,965.0
Operating Expenses
Gas Utility
Natural and propane gas		842.6		—		—			(72.5	)		770.1
Other operation and maintenance		449.7		—		—			(8.5	)		441.2
Depreciation and amortization		167.0		—		—			—			167.0
Taxes, other than income taxes		152.5		—		—			—			152.5
Total Gas Utility Operating Expenses		1,611.8		—		—			(81.0	)		1,530.8
Gas Marketing and Other *		—		37.8		32.8			69.5			140.1
Total Operating Expenses		1,611.8		37.8		32.8			(11.5	)		1,670.9
Operating Income (Loss)	$	276.6	$	33.8	$	(16.3	)	$	—		$	294.1
Net Economic Earnings (Loss)	$	183.1	$	22.9	$	(22.3	)	$	—		$	183.7
Capital Expenditures	$	457.7	$	—	$	41.7		$	—		$	499.4

2017	Gas Utility		Gas Marketing		Other			Eliminations			Consolidated
Revenues from external customers	$	1,660.0	$	79.3	$	1.4		$	—		$	1,740.7
Intersegment revenues		7.9		—		6.3			(14.2	)		—
Total Operating Revenues		1,667.9		79.3		7.7			(14.2	)		1,740.7
Operating Expenses
Gas Utility
Natural and propane gas		645.9		—		—			(75.4	)		570.5
Other operation and maintenance		389.9		—		—			(4.1	)		385.8
Depreciation and amortization		153.5		—		—			—			153.5
Taxes, other than income taxes		137.8		—		—			—			137.8
Total Gas Utility Operating Expenses		1,327.1		—		—			(79.5	)		1,247.6
Gas Marketing and Other *		—		74.1		12.8			65.3			152.2
Total Operating Expenses		1,327.1		74.1		12.8			(14.2	)		1,399.8
Operating Income (Loss)	$	340.8	$	5.2	$	(5.1	)	$	—		$	340.9
Net Economic Earnings (Loss)	$	181.5	$	6.8	$	(20.7	)	$	—		$	167.6
Capital Expenditures	$	412.6	$	—	$	25.5		$	—		$	438.1

* Operating Expenses for “Gas Marketing and Other” include depreciation and amortization for Gas Marketing ($0.1 for 2019, $0.0 for 2018, and $0.1 for 2017) and for Other ($2.2 for 2019, $1.4 for 2018, and $0.5 for 2017).

Total Assets at End of Year	2019			2018			2017
Gas Utility	$	6,094.6		$	5,606.7		$	5,551.2
Gas Marketing		212.3			295.3			246.2
Other		2,692.7			2,508.0			2,239.5
Eliminations		(1,380.4	)		(1,566.4	)		(1,490.2	)
Total Assets	$	7,619.2		$	6,843.6		$	6,546.7

Schedule of Reconciliation of Consolidated Net Economic Earnings to Consolidated Net Income

Reconciliation of Consolidated Net Income to Consolidated Net Economic Earnings	2019			2018			2017
Net Income	$	184.6		$	214.2		$	161.6
Adjustments, pre-tax:
Provision for ISRS rulings	12.2				—			—
Missouri regulatory adjustments		—			30.6			—
Unrealized loss (gain) on energy-related derivatives		1.2			(4.0	)		6.0
Realized gain on economic hedges prior to the sale of the    physical commodity		—			(0.3	)		(0.3	)
Acquisition, divestiture and restructuring activities		0.4			13.6			4.0
Income tax effect of adjustments		(3.3	)		(10.3	)		(3.7	)
Effect of the Tax Cuts and Jobs Act		—			(60.1	)		—
Net Economic Earnings	$	195.1		$	183.7		$	167.6