Leases - Lease-related Assets and Liabilities recorded on the Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Assets
Operating lease assets	$ 26	$ 38
Finance lease assets	170	170
Total lease assets	$ 196	$ 208
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property and equipment, net	Property and equipment, net
Liabilities
Current portion of operating lease liability	$ 12	$ 15
Current portion of finance lease liability	77	75
Noncurrent portion of operating lease liability	18	28
Noncurrent portion of finance lease liability	53	70
Long-term finance lease obligations	$ 160	$ 188
Weighted-average remaining lease term
Weighted-average remaining lease term, finance leases	2 years 9 months 21 days	3 years 4 months 6 days
Weighted-average remaining lease term, operating leases	1 year 10 months 9 days	2 years 10 days
Weighted-average discount rate
Weighted-average discount rate, operating leases (percentage)	5.00%	5.00%
Weighted-average discount rate, finance leases (percentage)	3.98%	4.33%

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Leases, Right-Of-Use Assets [Abstract]

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Leases, Weighted Average Discount Rate [Abstract]

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Operating And Finance Lease, Liability

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

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Amount, after accumulated amortization, of right-of-use asset from finance lease.

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Indicates line item in statement of financial position that includes finance lease right-of-use asset.

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of lessee's right to use underlying asset under operating lease.

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