Acquisitions (Schedule Of Intangible Assets Acquired) (Details) - Challenger And Hybrid [Member] $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 9,912
Trademarks And Tradenames [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	1,188
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amount	$ 8,724
Estimated Life	8 years
Minimum [Member] \| Trademarks And Tradenames [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Life	2 years
Maximum [Member] \| Trademarks And Tradenames [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Life	3 years

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.

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=73531372&loc=d3e2207-128464

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

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