Commitments and Contingencies - Future Minimum Annual Rental Commitments Under Non-Cancelable Future Operating and Finance Lease Commitments (Details) $ in Millions	Dec. 31, 2019 USD ($)
Operating Leases
2020	$ 10
2021	3
2022	2
2023	2
Thereafter	4
Total	21
Less: imputed interest	(3)
Present value of operating lease obligations	18
Finance Leases
2020	5
2021	5
2022	5
2023	2
Thereafter	0
Total	17
Less: imputed interest	(6)
Present value of finance lease obligations	$ 11

Finance Lease, Liability, Payments, Due After Year Four

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Lessee, Operating Lease, Liability, Payments Due After Year Four

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Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in next fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in next fiscal year following latest fiscal year.

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