CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (Unaudited) - USD ($) $ in Millions	Total	Common Stock	Capital in Excess of Par Value	Reinvested Earnings	Common Stock in Treasury	Accumulated Other Comprehensive (Loss) Income
Balances, period start at Jun. 30, 2017	$ 1,198.6	$ 276.7	$ 284.8	$ 1,321.8	$ (341.6)	$ (343.1)
Increase (Decrease) in Stockholders' Equity
Net income	115.5			115.5
Pension and postretirement benefits gain, net of tax	4.6					4.6
Marketable securities gain, net of tax	0.0
Net (loss) gain on derivative instruments, net of tax	23.1					23.1
Foreign currency translation	0.3					0.3
Cash Dividends:
Common	(17.2)			(17.2)
Share-based compensation plans	8.4		6.7		1.7
Stock options exercised	3.5	0.6	2.9
Balances, period end at Dec. 31, 2017	1,336.8	277.3	294.4	1,420.1	(339.9)	(315.1)
Balances, period start at Sep. 30, 2017						(331.1)
Increase (Decrease) in Stockholders' Equity
Net income	92.1
Pension and postretirement benefits gain, net of tax	2.5
Marketable securities gain, net of tax	0.0
Net (loss) gain on derivative instruments, net of tax	15.0
Foreign currency translation	(1.5)
Balances, period end at Dec. 31, 2017	1,336.8	277.3	294.4	1,420.1	(339.9)	(315.1)
Increase (Decrease) in Stockholders' Equity
Cumulative adjustment upon adoption of ASU 2017-12	0.0			1.0		(1.0)
Balances, period start at Jun. 30, 2018	1,485.9	278.6	310.0	1,475.9	(338.8)	(239.8)
Increase (Decrease) in Stockholders' Equity
Net income	67.0			67.0
Pension and postretirement benefits gain, net of tax	3.4					3.4
Marketable securities gain, net of tax	0.3					0.3
Net (loss) gain on derivative instruments, net of tax	(38.4)					(38.4)
Foreign currency translation	(2.0)					(2.0)
Cash Dividends:
Common	(19.3)			(19.3)
Share-based compensation plans	5.0		1.8		3.2
Stock options exercised	3.6	0.4	3.2
Balances, period end at Dec. 31, 2018	1,505.5	279.0	315.0	1,524.6	(335.6)	(277.5)
Balances, period start at Sep. 30, 2018						(261.1)
Increase (Decrease) in Stockholders' Equity
Net income	35.5
Pension and postretirement benefits gain, net of tax	1.7
Marketable securities gain, net of tax	0.0
Net (loss) gain on derivative instruments, net of tax	(15.4)
Foreign currency translation	(2.7)
Balances, period end at Dec. 31, 2018	$ 1,505.5	$ 279.0	$ 315.0	$ 1,524.6	$ (335.6)	$ (277.5)