Other Financial Data - Schedule of Other Current Assets (Details) - USD ($) $ in Millions	Jun. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Other Financial Data [Abstract]
Taxes receivable	$ 172		$ 114
Prepaid expenses	120		126
Receivables from divested business	10		28
Assets held for sale	47		0
Cost to fulfill contracts with customers	216		0
Other	167		21
Total	$ 732	$ 587	$ 289

Deferred Project Costs, Current

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Other Financial Data [Abstract]

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Other Tax Assets, Current

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount classified as accounts, notes and loans receivable attributable to disposal group held for sale or disposed of.

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Amount of current assets classified as other.

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Amount of other miscellaneous assets expected to be realized or consumed within one year or operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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