v3.20.2

Debt 144A due 2025 (Details) - USD ($) $ in Millions			6 Months Ended
	May 13, 2020	Feb. 05, 2020	Jun. 30, 2020	Jun. 30, 2019
Debt Instrument [Line Items]
Debt instrument, face amount		$ 1,200
Proceeds from debt issuance		$ 1,168	$ 2,400	$ 0
Senior Secured Notes | First-Lien Notes due 2025, 6.000%
Debt Instrument [Line Items]
Debt instrument, face amount	$ 700
Fixed interest rate	6.00%
Proceeds from debt issuance	$ 691
Senior Secured Notes | First-Lien Notes due 2025, 6.000% | Minimum
Debt Instrument [Line Items]
Required prior notice for debt redemption, term	10 days
Senior Secured Notes | First-Lien Notes due 2025, 6.000% | Maximum
Debt Instrument [Line Items]
Required prior notice for debt redemption, term	60 days
Senior Secured Notes | First-Lien Notes due 2025, 6.000% | Redemption prior to May 15, 2022
Debt Instrument [Line Items]
Debt redemption percentage	100.00%
Debt redemption, additional make-whole charge	1.00%
Debt redemption, basis spread on discount rate	0.50%
Senior Secured Notes | First-Lien Notes due 2025, 6.000% | Redemption prior to May 15, 2022; limited to 40% of aggregate principal
Debt Instrument [Line Items]
Debt redemption percentage	106.00%
Redemption limitation based on aggregate principal	40.00%
Minimum aggregate principal following redemption	60.00%
Maximum term allowed for redemption following offering	120 days
Senior Secured Notes | First-Lien Notes due 2025, 6.000% | Redemption after May 14, 2022
Debt Instrument [Line Items]
Debt redemption percentage	103.00%
Senior Secured Notes | First-Lien Notes due 2025, 6.000% | Redemption upon change in control
Debt Instrument [Line Items]
Debt redemption percentage	101.00%

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