DEBT, Credit Agreement (Details) $ in Millions, ¥ in Billions	3 Months Ended
	Mar. 31, 2018 USD ($)		Mar. 31, 2018 JPY (¥)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 JPY (¥)	Oct. 09, 2014 USD ($)	Oct. 09, 2014 JPY (¥)
Credit Agreement [Member] | Maximum [Member]
Debt [Abstract]
Consolidated leverage ratio	2.25
Credit Agreement [Member] | Minimum [Member]
Debt [Abstract]
Consolidated interest coverage ratio	3.00
Term Loan Facility [Member]
Debt [Abstract]
Original principal amount	$ 127.5					$ 127.5
Term of facility	5 years
Outstanding balance	$ 90.8	[1],[2]		$ 94.8
Japanese Yen Term Loan Facility [Member]
Debt [Abstract]
Original principal amount | ¥			¥ 6.6				¥ 6.6
Term of facility	5 years
Outstanding balance	$ 44.2	[1],[2]	¥ 4.7	43.5	¥ 4.9
Revolving Credit Facility [Member]
Debt [Abstract]
Borrowing capacity						$ 187.5
Term of facility	5 years
Outstanding balance	$ 122.5	[1],[2]		$ 47.5

[1] As of March 31, 2018, the current portion of the Company's debt (i.e. becoming due in the next 12 months) included $17.5 million of the balance of its U.S. dollar denominated debt under the Credit Agreement facility, $8.5 million of the balance of its Japanese yen-denominated debt under the Credit Agreement facility, $4.1 million of the Japan subsidiary loan and the $210.0 million convertible note. The Company classified the $122.5 million borrowed under the revolving line of credit as short term because it was the Company's intention to use the 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 debt issuance costs of $1.7 million related to the Credit Agreement, which is not reflected in this table.