Equity Compensation - Additional Disclosures (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation expense	$ 21.7	$ 13.8	$ 8.9
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock unit vesting period	3 years
Unrecognized compensation expense	$ 31.0
Unrecognized compensation expense, weighted average recognition period (in Years)	2 years
Aggregate fair value of awards vested	$ 11.1	$ 13.7	$ 23.2

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

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