Other Financial Data - Schedule of Other Non-current Assets (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Other Financial Data [Abstract]
Costs to obtain contracts with customers	$ 184	$ 171
Investments	74	53
Leases	89	100
Taxes receivable	125	102
Other	138	144
Total	$ 610	$ 570

Other Financial Data [Abstract]

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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 noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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- Definition

Amount, after accumulated amortization, of right-of-use asset from finance lease.

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-Publisher FASB
-Name Accounting Standards Codification
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Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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

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Amount of noncurrent assets classified as other.

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