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Business Segment and Geographical Information - Distribution of Capital Expenditure by Geographical Area (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Capital expenditures	$ 48,397	$ 44,717	$ 42,601
Ireland
Segment Reporting Information [Line Items]
Capital expenditures	30,942	24,468	27,670
Rest of Europe
Segment Reporting Information [Line Items]
Capital expenditures	2,590	2,819	2,851
U.S.
Segment Reporting Information [Line Items]
Capital expenditures	9,311	11,027	8,432
Other
Segment Reporting Information [Line Items]
Capital expenditures	$ 5,554	$ 6,403	$ 3,648

X

- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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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.

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