FINANCING ARRANGEMENTS - Schedule of Senior Term Notes (Details) - USD ($)	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Debt Instrument [Line Items]
Net carrying amount of Senior Term Notes	$ 120,435,000		$ 120,002,000
Senior Notes | Senior term notes - 5.50%
Debt Instrument [Line Items]
Principal amount on the Senior Term Notes	123,000,000	$ 123,000,000.0
Unamortized debt discount	(2,565,000)
Net carrying amount of Senior Term Notes	$ 120,435,000		$ 0