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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

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- 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 + 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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