Summary of Significant Accounting Policies - Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the computation	10.8	5.0	4.1
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the computation	0.3	0.9	1.8
Restricted Stock Units (RSUs)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the computation	4.5	2.7	2.3
Warrant
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares excluded from the computation	6.0	1.4	0.0