Other Financial Data - Schedule of Other Current Assets (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Other Financial Data [Abstract]
Cost to fulfill contracts with customers	$ 236	$ 329
Prepaid expenses	108	97
Taxes receivable	81	113
Other	106	79
Total	$ 531	618
Receivables from divested business		$ 12

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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