Basis of Presentation and Summary of Significant Accounting Policies Contract Assets and Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Current portion of contract assets	$ 9	$ 9
Contract with Customer, Liability, Current	616	502
Non-current portion of contract liabilities	75	$ 81
Revenue recognized that was included in contract liabilities	198
Remaining performance obligations	$ 4,000

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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