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Distribution of Depreciation and Amortization by Geographical Area (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 17,046	$ 14,395	$ 33,944	$ 28,843
Ireland
Segment Reporting Information [Line Items]
Depreciation and amortization	7,979	6,508	15,864	12,480
Rest of Europe
Segment Reporting Information [Line Items]
Depreciation and amortization	1,624	1,371	3,163	3,029
U.S.
Segment Reporting Information [Line Items]
Depreciation and amortization	6,302	5,581	12,601	11,529
Rest of World
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 1,141	$ 935	$ 2,316	$ 1,805

X

- Definition

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

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+ References

No definition available.

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