INCOME TAXES (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Income taxes (Note 12)	$ 22,635	$ 14,449	$ 44,687	$ 34,007
Pre-tax income	83,966	$ 45,758	$ 161,866	$ 118,940
Effective income tax rate (as a percent)			27.60%	28.60%
Unrecognized tax benefits	14,821		$ 14,821
Unrecognized tax benefits that, if recognized, would be reflected as a component of income tax expense	11,123		11,123
Reasonably possible reduction in prior years' unrecognized tax benefits during the next twelve months	$ 1,135		$ 1,135

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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Amount of unrecognized tax benefits.

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