Benefit Obligations (Tables)

6 Months Ended

Jun. 30, 2018

Retirement Benefits [Abstract]

Schedule of Net Periodic Benefit Costs Recognized

The components of net periodic benefit cost are as follows:

	Three Months Ended June 30,							Six Months Ended June 30,
	2018			2017				2018			2017
	Pension Benefits		Post-retirement Benefits	Pension Benefits		Post-retirement Benefits		Pension Benefits		Post-retirement Benefits	Pension Benefits		Post-retirement Benefits
	(In $ millions)
Service cost	3		—	2		—		5		—	4		—
Interest cost	26		1	26		1		52		1	53		1
Expected return on plan assets	(53	)	—	(49	)	—		(105	)	—	(98	)	—
Amortization of prior service cost (credit), net	—		—	—		(1	)	—		—	—		(1	)
Special termination benefit	1		—	1		—		1		—	1		—
Total	(23	)	1	(20	)	—		(47	)	1	(40	)	—

Schedule of Company Commitments to Fund Benefit Obligations

Benefit obligation funding is as follows:

	As of June 30, 2018	Total Expected 2018
	(In $ millions)
Cash contributions to defined benefit pension plans	12	23
Benefit payments to nonqualified pension plans	11	21
Benefit payments to other postretirement benefit plans	1	5
Cash contributions to German multiemployer defined benefit pension plans(1)	4	8