Noncurrent Other Liabilities (Tables)

12 Months Ended

Dec. 31, 2018

Other Liabilities, Noncurrent [Abstract]

Schedule of Noncurrent Other Liabilities

	As of December 31,
	2018	2017
	(In $ millions)
Asset retirement obligations	13	7
Deferred proceeds	44	47
Deferred revenue	7	6
Derivatives (Note 22)	11	—
Environmental (Note 16)	49	59
Income taxes payable (Note 19)	—	197
Insurance	37	43
Other	47	54
Total	208	413

Schedule of Changes in Asset Retirement Obligations

Changes in asset retirement obligations are as follows:

	Year Ended December 31,
	2018		2017		2016
	(In $ millions)
Balance at beginning of year	26		29		36
Additions(1)	2		—		2
Accretion	—		1		1
Payments	(4	)	(5	)	(10	)
Revisions to cash flow estimates(2)	(8	)	1		—
Balance at end of year	16		26		29

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⁽¹⁾  Primarily relates to sites which management no longer considers to have an indeterminate life.

⁽²⁾  Primarily relates to revisions to the estimated cost and timing of future obligations.