Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Guarantees - Textual (Details) - USD ($) $ in Millions	9 Months Ended
Guarantees - Textual (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Guarantor Obligations [Line Items]
Environmental accruals for known contamination in carrying amount recorded for indemnifications	$ 191	$ 180
Australia Pacific APLNG [Member]
Guarantor Obligations [Line Items]
Ownership percentage in equity investment	37.50%
Finance Reserve Guarantee [Member] \| Australia Pacific APLNG [Member]
Guarantor Obligations [Line Items]
Terms of Guarantees Outstanding	9 years
Maximum potential amount of future payments	$ 170
Guarantor Obligations, Current Carrying Value	$ 14
Guarantee existing sales agreement of natural gas delivery \| Australia Pacific APLNG [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Terms of Guarantees Outstanding	1 to 21 years
Max potential future payments-reckless breach [Member] \| Australia Pacific APLNG [Member]
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	$ 1,200
Max potential future payments-prorata share [Member] \| Australia Pacific APLNG [Member]
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	670
Continued development [Member] \| Australia Pacific APLNG [Member]
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	180
Guarantor Obligations, Current Carrying Value	$ 11
Continued development [Member] \| Australia Pacific APLNG [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Terms of Guarantees Outstanding	15 to 24 years
Other Guarantees [Member]
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	$ 720
Guarantor Obligations, Current Carrying Value	$ 11
Other Guarantees [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Terms of Guarantees Outstanding	one to five years
Indemnifications [Member]
Guarantor Obligations [Line Items]
Guarantor Obligations, Current Carrying Value	$ 30