Stock-Based Compensation - Schedule of Nonvested Restricted Stock Activity (Details) $ / shares in Units, shares in Thousands, $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($) $ / shares shares
Weighted- Average Grant Date Fair Value
Weighted-average period for recognition	2 years 7 months 9 days
Restricted Stock Units
Number of Grants
Unvested balance at beginning of the period (in shares) \| shares	397
Granted (in shares) \| shares	275
Vested (in shares) \| shares	(137)
Forfeited (in shares) \| shares	(38)
Unvested balance at end of the period (in shares) \| shares	497
Weighted- Average Grant Date Fair Value
Unvested balance at beginning of the period (in dollars per share) \| $ / shares	$ 39.20
Granted (in dollars per share) \| $ / shares	67.45
Vested (in dollars per share) \| $ / shares	38.64
Forfeited (in dollars per share) \| $ / shares	42.80
Unvested balance at end of the period (in dollars per share) \| $ / shares	$ 54.68
Unrecognized compensation cost \| $	$ 20.7
Weighted-average period for recognition	1 year 9 months 14 days
Performance-Based Restricted Stock Units
Number of Grants
Unvested balance at beginning of the period (in shares) \| shares	0
Granted (in shares) \| shares	78
Vested (in shares) \| shares	0
Forfeited (in shares) \| shares	(3)
Unvested balance at end of the period (in shares) \| shares	75
Weighted- Average Grant Date Fair Value
Unvested balance at beginning of the period (in dollars per share) \| $ / shares	$ 0
Granted (in dollars per share) \| $ / shares	52.99
Vested (in dollars per share) \| $ / shares	0
Forfeited (in dollars per share) \| $ / shares	52.99
Unvested balance at end of the period (in dollars per share) \| $ / shares	$ 52.99
Unrecognized compensation cost \| $	$ 4.0
Minimum
Weighted- Average Grant Date Fair Value
Actual awards earned percentage of expected expense recognized	0.00%
Maximum
Weighted- Average Grant Date Fair Value
Actual awards earned percentage of expected expense recognized	200.00%

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 cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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 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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Stock-Based Compensation arrangement By Share-based Payment Awards, Actual Awards Earned Percentage Of Expense Recognized

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