Stock-Based Compensation and Stockholders' Equity - 2015 Equity Incentive Plan (“2015 Plan”) (Details) $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	0
Exercise of stock options (in shares)	110,000
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	642,000
Equity instruments other than options, fair value \| $	$ 46
Share conversion (in shares)	1
Vested (shares)	832,000
Restricted stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years
Restricted stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	81,000
Award vesting period	3 years
Aggregate intrinsic value, nonvested \| $	$ 9
Vested (shares)	162,000
Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target payout range	0.00%
Performance Shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target payout range	200.00%
Market-based Stock Units (MSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	147,000
Award vesting period	3 years
Aggregate intrinsic value, nonvested \| $	$ 15
Vested (shares)	208,000
Market-based Stock Units (MSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target payout range	0.00%
Market-based Stock Units (MSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target payout range	200.00%

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