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Distribution Income from Operations, including Restructuring, 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] |  |  |  |
Income from operations | $ 81,912 | $ 77,998 | $ 173,632 | $ 163,656
Income from operations excluding restructuring | 94,402 | 85,751 | 186,122 | 171,409
Ireland |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Income from operations | 49,587 | 38,640 | 119,397 | 102,608
Income from operations excluding restructuring | 62,077 | 46,393 | 131,887 | 110,361
Rest of Europe |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Income from operations | 11,658 | 8,899 | 16,826 | 12,598
Income from operations excluding restructuring | 11,658 | 8,899 | 16,826 | 12,598
U.S. |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Income from operations | 14,703 | 26,248 | 26,505 | 36,747
Income from operations excluding restructuring | 14,703 | 26,248 | 26,505 | 36,747
Rest of World |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Income from operations | 5,964 | 4,211 | 10,904 | 11,703
Income from operations excluding restructuring | $ 5,964 | $ 4,211 | $ 10,904 | $ 11,703

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