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

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Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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Share-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Payment Arrangement, Expense	$ 3.7	$ 1.9	$ 8.7	$ 6.0
Excess Tax Benefit on Stock Plans			$ 0.7	2.1
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award
Shares granted			16,211
Vesting period of new awards granted			3 years
Fair value of shares vested			$ 1.0	$ 0.9
Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Weighted average grant date fair value, in dollars per share			$ 63.65