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.

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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.

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- Definition

Total revenue reported by the acquired entity for its previous full fiscal year before the business acquisition.

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No definition available.

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- Definition

Amount of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit, acquired at the acquisition date.

+ References

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- Definition

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

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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BUSINESS ACQUISITIONS AND DIVESTITURES (Details) $ in Thousands, £ in Millions			12 Months Ended
	Sep. 01, 2015 GBP (£)	Sep. 01, 2015 USD ($)	Aug. 31, 2015 GBP (£)	Aug. 31, 2015 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Business Acquisitions and Divestitures [Line Items]
Goodwill					$ 543,903	$ 527,150	$ 582,336
Cromwell [Member]
Business Acquisitions and Divestitures [Line Items]
Sales reported by acquired entity for last fiscal year			£ 285	$ 437,000
Acquisition price	£ 310	$ 464,000
Goodwill		123,000
Cromwell [Member] \| Customer relationships [Member]
Business Acquisitions and Divestitures [Line Items]
Finite lived intangibles, acquired		$ 132,000
Acquired finite-lived intangible assets, useful life	15 years	15 years
Cromwell [Member] \| Tradename [Member]
Business Acquisitions and Divestitures [Line Items]
Indefinite lived intangibles, acquired		$ 84,000