CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Capital in Excess of Par Value	Reinvested Earnings	Reinvested Earnings Cumulative Effect, Period of Adoption, Adjustment	Common Stock in Treasury	Accumulated Other Comprehensive (Loss) Income	Accumulated Other Comprehensive (Loss) Income Cumulative Effect, Period of Adoption, Adjustment
Balances, beginning of period at Jun. 30, 2018	$ 1,485.9	$ 0.0	$ 278.6	$ 310.0	$ 1,475.9	$ 1.0	$ (338.8)	$ (239.8)	$ (1.0)
Increase (Decrease) in Stockholders' Equity
Accounting Standards Update [Extensible Enumeration]	us-gaap:AccountingStandardsUpdate201712Member
Net (loss) income	$ 167.0				167.0
Pension and postretirement benefits gain (loss), net of tax	(72.9)							(72.9)
Marketable securities gain, net of tax	0.3							0.3
Net gain (loss) on derivative instruments, net of tax	(37.6)							(37.6)
Foreign currency translation	(0.8)							(0.8)
Cash dividends:
Common	(38.6)				(38.6)
Share-based compensation plans	12.9			6.9			6.0
Stock options exercised	3.9		0.4	3.5
Balances, end of period at Jun. 30, 2019	$ 1,520.1		$ 279.0	320.4	1,605.3		$ (332.8)	(351.8)
Balances, beginning of period (in shares) at Jun. 30, 2018	47,191,744		55,712,229				8,520,485
Common Shares
Stock options exercised (in shares)	96,514		96,514
Share-based compensation plans (in shares)	182,105						182,105
Balances, end of period (in shares) at Jun. 30, 2019	47,470,363		55,808,743				8,338,380
Increase (Decrease) in Stockholders' Equity
Net (loss) income	$ 1.5				1.5
Pension and postretirement benefits gain (loss), net of tax	(41.0)							(41.0)
Marketable securities gain, net of tax	0.0
Net gain (loss) on derivative instruments, net of tax	3.7							3.7
Foreign currency translation	(8.9)							(8.9)
Cash dividends:
Common	(38.8)				(38.8)
Share-based compensation plans	4.8		$ 0.5	(2.7)			$ 7.0
Stock options exercised	4.3		0.6	3.7
Balances, end of period at Jun. 30, 2020	$ 1,445.7		$ 280.1	321.4	1,568.0		$ (325.8)	(398.0)
Common Shares
Stock options exercised (in shares)	117,049		117,049
Share-based compensation plans (in shares)	263,056		86,956				176,100
Balances, end of period (in shares) at Jun. 30, 2020	47,850,468		56,012,748				8,162,280
Increase (Decrease) in Stockholders' Equity
Net (loss) income	$ (229.6)				(229.6)
Pension and postretirement benefits gain (loss), net of tax	175.2							175.2
Marketable securities gain, net of tax	0.0
Net gain (loss) on derivative instruments, net of tax	18.0							18.0
Foreign currency translation	12.5							12.5
Cash dividends:
Common	(39.1)				(39.1)
Share-based compensation plans	9.2			0.8			$ 8.4
Stock options exercised	0.4			0.4
Balances, end of period at Jun. 30, 2021	$ 1,392.3		$ 280.1	$ 322.6	$ 1,299.3		$ (317.4)	$ (192.3)
Common Shares
Stock options exercised (in shares)	11,871		11,871
Share-based compensation plans (in shares)	178,337						178,337
Balances, end of period (in shares) at Jun. 30, 2021	48,040,676		56,024,619				7,983,943