Organization And Description Of Business [Line Items]

No definition available.

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- Definition

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=65878427&loc=d3e957-107759

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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Business and Organization (Detail) $ in Millions		3 Months Ended	12 Months Ended
Business and Organization (Detail) $ in Millions	Aug. 04, 2015 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2017 Segment	Dec. 31, 2016 Acquisition	Dec. 31, 2015 Acquisition
Organization And Description Of Business [Line Items]
Number of reportable segments \| Segment			2
Acquisitions 2016
Organization And Description Of Business [Line Items]
Number of business acquisitions \| Acquisition				5
Acquisitions 2015
Organization And Description Of Business [Line Items]
Number of business acquisitions \| Acquisition					11
Fiber Optic Licensing Division
Organization And Description Of Business [Line Items]
Sales price of fiber optic licensing operations	$ 1,000.0
Net cash proceeds from sale of fiber optic licensing operations	$ 848.2
Gain on sale, net of tax		$ 171.0