Leases - Future Minimum Lease Payments (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Operating Leases
2021, remaining	$ 43
2022	175
2023	121
2024	114
2025	106
Thereafter	509
Total minimum lease payments	1,068
Less: Amount representing interest	(226)
Present value of minimum lease payments	842	$ 970
Current	$ 145	$ 147
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other Liabilities, Current	Other Liabilities, Current
Noncurrent	$ 697	$ 823
Finance Leases
2021, remaining	3
2022	14
2023	14
2024	14
2025	14
Thereafter	137
Total minimum lease payments	196
Less: Amount representing interest	(48)
Present value of minimum lease payments	148	153
Current	7	7
Noncurrent	$ 141	$ 146
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Current portion of long-term debt	Current portion of long-term debt
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Long-term debt	Long-term debt

Finance Lease, Liability, to be Paid, Due after Year Four

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- Definition

Lessee, Operating Lease, Liability, to be Paid, Due after Year Four

+ References

No definition available.

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No definition available.

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- Definition

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=123408670&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=123391704&loc=SL77918627-209977

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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- Definition

Indicates line item in statement of financial position that includes current finance lease liability.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918631-209977

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- Definition

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

+ References

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- Definition

Indicates line item in statement of financial position that includes noncurrent finance lease liability.

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- Definition

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

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in remainder of current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980

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

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

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

+ References

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

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

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

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- Definition

Indicates line item in statement of financial position that includes current operating lease liability.

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

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