Other noncurrent liabilities Other noncurrent liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Other Noncurrent Liabilities [Abstract]
Reserve for underground storage tank removal	$ 67		$ 54
Reserve for environmental remediation	25		29
Unfavorable lease liability	14		16
Accrued straight-line rent	0		12
Other	11		12
Other Liabilities, Noncurrent	$ 117	$ 111	$ 123

Other Noncurrent Liabilities [Abstract]

No definition available.

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- Definition

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable after twelve months or beyond the next operating cycle if longer.

+ References

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- Definition

For a classified balance sheet, the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, more than one year after the balance sheet date.

+ References

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- Definition

This element represents a liability associated with the acquisition of an off-market lease when the terms of the lease are unfavorable to the market terms for the lease at the date of acquisition.

+ References

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- Definition

Amount of a reclamation liability that is associated with a legal obligation for the closure and reclamation of oil and gas properties.

+ References

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- Definition

Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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- Definition

Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.

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