Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Rate of weighted-average expected volatility for award under share-based payment arrangement.

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Gross number of share options (or share units) granted during the period.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 8.6	$ 3.2	$ 11.5	$ 6.2
Risk-free interest rate	1.67%
Weighted-average volatility factor	24.69%
Equity Classified Awards Expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 6.7	2.9	10.4	6.4
Liability Classified Awards Expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	1.9	$ 0.3	1.1	$ (0.2)
Employee Stock Option
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total unrecognized compensation cost	$ 5.2		$ 5.2
Weighted-average remaining requisite vesting period			2 years 6 months
Fair value assumptions, expected volatility rate			25.87%
Risk-free interest rate			1.68%
Fair value assumptions, expected dividend rate			1.27%
Fair value assumptions, expected term			6 years
Options granted (in shares)			334,000
Performance Based Stock Options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Options granted (in shares)			0
Performance-Based Restricted Stock Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Grants in period (in shares)	378,000		378,000
Award vesting period			3 years
Restricted Stock Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total unrecognized compensation cost	$ 54.2		$ 54.2
Weighted-average remaining requisite vesting period			2 years
Restricted Stock
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total unrecognized compensation cost	0.2		$ 0.2
Weighted-average remaining requisite vesting period			8 months 12 days
Officer
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based payment arrangement, accelerated cost	$ 3.9		$ 3.9