Percentage Of Company-Wide Revenues

No definition available.

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- Definition

Revenue, Remaining Performance Obligation, Optional Exemption, Contract Term

+ References

No definition available.

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- Definition

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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- Definition

Amount, before accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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- Definition

Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130549-203045

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84173487&loc=SL51747714-108306

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Revenue Recognition (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Revenue Recognition (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue recognized which was included in the contract liability balance		$ 450
Capitalized contract costs, amortization		106
Capitalized contract cost, impairment loss		0
Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effect adjustment of ASU adoption			$ 208
Retained Earnings \| Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effect adjustment of ASU adoption			$ 208
Product
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of consolidated revenue (less than)	4.00%
Sales Commissions
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Capitalized contract costs		322
Conversion or Implementation Costs
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Capitalized contract costs		$ 97
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Remaining revenue performance obligation, optional exemption, contract term		3 years
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Remaining revenue performance obligation, optional exemption, contract term		5 years