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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Net Investment Hedge (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 24, 2016 | Sep. 30, 2017 | Sep. 24, 2016
Derivative [Line Items] |  |  |  |
Realized gain on net investment hedge, before tax | $ 5,123 |  | $ 5,123 |
Realized gain on net investment hedge, net of tax | 3,150 |  | 3,150 |
Derivatives used in Net Investment Hedge, Net of Tax, Period Increase (Decrease) | (740) | $ 1,972 | 1,816 | $ 4,897
Foreign Currency Forward Contract |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, notional amount |  | $ 44,000 |  | $ 44,000
Australia, Dollars | Foreign Currency Forward Contract |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, notional amount | 27,000 |  | 27,000 |
United Kingdom, Pounds | Foreign Currency Forward Contract |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, notional amount | $ 18,500 |  | $ 18,500 |

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