DEBT (Details) $ in Thousands, ¥ in Billions	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($)		Sep. 30, 2016 USD ($)		Sep. 30, 2016 JPY (¥)	Jun. 16, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 JPY (¥)
Debt [Abstract]
Current portion of long-term debt	$ 73,328		$ 73,328				$ 67,849
Maximum [Member]
Debt [Abstract]
Consolidated leverage ratio	2.25
Minimum [Member]
Debt [Abstract]
Consolidated interest coverage ratio	3.00
Credit Agreement [Member]
Debt [Abstract]
Debt discount	$ 3,400		3,400
Term Loan Facility [Member]
Debt [Abstract]
Original principal amount	127,500		127,500
Balance	$ 111,600	[1],[2]	$ 111,600	[1],[2]			118,700
Interest rate			Variable 30 day: 3.2744
Interest rate	3.2744%		3.2744%		3.2744%
Repayment terms			One half of the principal amount payable in increasing quarterly installments over a five-year period that began on December 31, 2014, with the remainder payable at the end of the five-year term.
Term			5 years
Current portion of long-term debt	$ 60,300		$ 60,300
Japanese Yen Term Loan Facility [Member]
Debt [Abstract]
Original principal amount | ¥					¥ 6.6
Balance	$ 56,900	[1],[2]	$ 56,900	[1],[2]	¥ 5.8		51,100	¥ 6.1
Interest rate			Variable 30 day: 2.75
Interest rate	2.75%		2.75%		2.75%
Repayment terms			One half of the principal amount payable in increasing quarterly installments over a five-year period that began on December 31, 2014, with the remainder payable at the end of the five-year term.
Term			5 years
Current portion of long-term debt	$ 6,500		$ 6,500
Revolving Credit Facility [Member]
Debt [Abstract]
Borrowing capacity	187,500		187,500
Balance	$ 47,500	[1],[2]	$ 47,500	[1],[2]			47,500
Interest rate			Variable 30 day: 3.2744
Interest rate	3.2744%		3.2744%		3.2744%
Repayment terms			Revolving line of credit expires October 2019.
Korea Subsidiary Loan [Member]
Debt [Abstract]
Original principal amount	$ 20,000		$ 20,000
Balance	$ 10,000	[1],[2]	$ 10,000	[1],[2]			20,000
Interest rate	1.12%		1.12%		1.12%
Repayment terms			One half of the principal amount payable on March 17, 2017 and the remainder payable on March 16, 2018.
Japan Subsidiary Loan [Member]
Debt [Abstract]
Original principal amount | ¥					¥ 2.0
Balance	$ 13,200	[1],[2]	$ 13,200	[1],[2]	¥ 1.3		16,600	¥ 2.0
Interest rate	0.66%		0.66%		0.66%
Repayment terms			Payable in semi-annual installments over three years that began on January 31, 2016.
Term			3 years
Current portion of long-term debt	$ 6,500		$ 6,500
Convertible Note [Member]
Debt [Abstract]
Original principal amount	210,000	[3]	210,000	[3]		$ 210,000
Balance	$ 210,000	[2],[3]	$ 210,000	[2],[3]			$ 0
Interest rate	7.10%		7.10%		7.10%
Interest rate	4.75%		4.75%		4.75%
Repayment terms			Principal amount payable on June 15, 2020.
Debt discount	$ 10,231		$ 10,231
Debt discount	$ 16,100		$ 16,100

[1] As of September 30, 2016, the current portion of the Company's debt (i.e., becoming due in the next 12 months) included $60.3 million of the balance of its U.S. dollar-denominated debt under the Credit Agreement term loan facility, $6.5 million of the balance of its Japanese yen-denominated debt under the Credit Agreement term loan facility, $10.0 million of the Korea subsidiary loan and $6.5 million of the Japan subsidiary loan. The Company has classified the amount borrowed under the Credit Agreement revolving credit facility as short term because it is the Company's intention to use this line of credit to borrow and pay back funds over short periods of time.

[2] The carrying value of the debt reflects the amounts stated in the above table less a debt discount of $3.4 million on the Credit Agreement and $16.1 million on the convertible debt, which is not reflected in this table.

[3] See Note 12 for more information regarding the convertible note.