v3.19.3.a.u2

Stock-Based Compensation - Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Jan. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2019
Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate grant date fair value of awards		$ 29.3	$ 11.5	$ 29.3
Vesting period		3 years
Number of Restricted Stock Units
Granted (in shares)		1,275,955	186,433
Vested (in shares)				0
Restricted Stock Units and Performance Restricted Stock Units
Number of Restricted Stock Units
Outstanding balance at the beginning of the period (in shares)	3,694,915		1,139,045	1,139,045
Granted (in shares)				3,388,919
Vested (in shares)				(538,752)
Forfeited (in shares)				(294,297)
Outstanding balance at the end of the period (in shares)		3,694,915		3,694,915
Weighted-Average Grant Date Fair Value per Share
Outstanding at the beginning of the period (in dollars per share)	$ 35.76		$ 52.47	$ 52.47
Granted (in dollars per share)				32.50
Vested (in dollars per share)				42.74
Forfeited (in dollars per share)				50.15
Outstanding at the end of the period (in dollars per share)		$ 35.76		$ 35.76
Minimum | Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 year
PRSU award vesting percentage		0.00%
Minimum | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
Maximum | Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
PRSU award vesting percentage		200.00%
Maximum | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				4 years
Subsequent Event | Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate grant date fair value of awards	$ 37.6
Vesting period	3 years
Number of Restricted Stock Units
Granted (in shares)	1,900,000
Subsequent Event | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate grant date fair value of awards	$ 34.1
Number of Restricted Stock Units
Granted (in shares)	1,700,000
Subsequent Event | Minimum | Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSU award vesting percentage	0.00%
Subsequent Event | Maximum | Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSU award vesting percentage	200.00%

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