Adoption of Revenue Recognition Guidance - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total Stockholders’ Equity	$ 233.5	$ 576.7	$ 421.3		$ 102.4
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total Stockholders’ Equity					37.6
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total Stockholders’ Equity	$ (65.2)	$ 244.9	$ 103.9		(71.0)
Retained Earnings | Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total Stockholders’ Equity				$ 37.6	$ 37.6