Other Financial Data - Schedule of Other Current Assets (Details) - USD ($) $ in Millions	Sep. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Other Financial Data [Abstract]
Cost to fulfill contracts with customers	$ 248		$ 0
Taxes receivable	196		114
Prepaid expenses	109		126
Receivables from divested business	11		28
Other	163		21
Total	$ 727	$ 587	$ 289

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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