Business, Basis of Presentation and Significant Accounting Policies (Remaining Performance Obligations) (Narrative) (Details) $ in Billions	Jun. 30, 2018 USD ($)
Revenue from Contract with Customer [Abstract]
Revenue recognition, remaining performance obligations, contract price allocated (in dollars)	$ 5.1
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-07-01
Revenue from Contract with Customer [Abstract]
Revenue recognition, remaining performance obligations, contract price allocated (in dollars)	$ 3.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue recognition, remaining performance obligations, completion period (in months)	6 months

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045

+ Details

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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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- Definition

Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045

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