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Share-based Compensation - Time Vested Restricted Stock Units - Additional Information (Details) - Time-vested RSUs - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based compensation Expense
Granted (in dollars per share)	$ 30.47	$ 63.01	$ 54.85
Fair value of RSU's vested	$ 42.4	$ 34.5	$ 31.5
Unrecognized compensation cost	$ 66.6
Weighted average period for unrecognized compensation cost expected to be recognized	1 year 10 months 24 days

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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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No definition available.

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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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The weighted average fair value at grant date for nonvested equity-based awards issued 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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