Other Financial Data - Schedule of Other Current Assets (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Other Financial Data [Abstract]
Cost to fulfill contracts with customers	$ 239	$ 329
Prepaid expenses	123	97
Taxes receivable	177	113
Other	92	79
Total	$ 631	618
Receivables from divested business		$ 12

Other Financial Data [Abstract]

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Other Tax Assets, Current

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- Definition

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 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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