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Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2017
Accounting Policies [Abstract] |
Cumulative Translation Adjustments Included in Accumulated Other Comprehensive Income | The following table presents the balances of the Company’s cumulative translation adjustments included in accumulated other comprehensive loss, exclusive of taxes.
| (In thousands) |
December 31, 2014 | $ | (26,675 | )
December 31, 2015 | $ | (55,175 | )
December 31, 2016 | $ | (51,709 | )
December 31, 2017 | $ | (39,190 | )

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