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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Comprehensive Income (Details) $ in Thousands | 3 Months Ended
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Mar. 31, 2018 USD ($)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] |
Balance at the beginning of the period | $ (279,022)
Balance at the end of the period | (276,629)
Foreign Currency Translation Adjustments |
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] |
Balance at the beginning of the period | (171,399)
Current-period comprehensive income (loss) | 3,256
Balance at the end of the period | (168,143)
Gain/(Loss) on Hedging Activities |
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] |
Balance at the beginning of the period | 6,357
Current-period comprehensive income (loss) | (863)
Balance at the end of the period | 5,494
Defined Benefit Pension Plan |
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] |
Balance at the beginning of the period | (113,980)
Current-period comprehensive income (loss) | 0
Balance at the end of the period | (113,980)
Accumulated Other Comprehensive Loss |
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] |
Balance at the beginning of the period | (279,022)
Current-period comprehensive income (loss) | 2,393
Balance at the end of the period | $ (276,629)

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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e681-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580 + Details
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- Definition Amount after tax of other comprehensive income (loss) attributable to parent entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=64809438&loc=SL4573702-111684 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4569616-111683 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4569643-111683 + Details
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