Guarantees (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Australia Pacific APLNG [Member]
Guarantor Obligations [Line Items]
Ownership percentage in equity investment	37.50%
Continued development [Member] \| Australia Pacific APLNG [Member]
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	$ 140
Continued development [Member] \| Australia Pacific APLNG [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Terms of guarantees outstanding	P27Y
Other Guarantees [Member]
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	$ 780
Other Guarantees [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Terms of guarantees outstanding	P4Y
Indemnifications [Member]
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	$ 90
Environmental accruals for known contamination in carrying amount recorded for indemnifications	30
Guarantee existing sales agreement of natural gas delivery \| Australia Pacific APLNG [Member]
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	$ 800
Guarantee existing sales agreement of natural gas delivery \| Australia Pacific APLNG [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Terms of guarantees outstanding	P23Y
Max potential future payments-reckless breach [Member] \| Australia Pacific APLNG [Member] \| Maximum [Member]
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	$ 1,400
Finance Reserve Guarantee [Member] \| Australia Pacific APLNG [Member]
Guarantor Obligations [Line Items]
Maximum potential amount of future payments	$ 170
Terms of guarantees outstanding	P12Y
Guarantor Obligations, Current Carrying Value	$ 14

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

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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