FINANCING ARRANGEMENTS (Tables)

9 Months Ended

Sep. 30, 2018

Debt Disclosure [Abstract]

Schedule of Notes

The carrying amount of the Notes consisted of the following as of September 30, 2018 and December 31, 2017 (in thousands):

	September 30, 2018			December 31, 2017
Liability component:
Principal amount	$	250,000		$	250,000
Less: debt discount	(51,425		)	(60,247		)
Net carrying amount of liability component	$	198,575		$	189,753
Net carrying amount of equity component	$	67,014		$	67,014

Schedule of Convertible Debt Interest Expense

During the three and nine months ended September 30, 2018 and 2017, we recognized interest costs on the Notes as follows (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2018		2017		2018		2017
Contractual interest (3.25% of the principal amount per annum)	$	2,032	$	2,032	$	6,096	$	6,096
Amortization of debt discount	3,016		2,722		8,822		7,964
Total	$	5,048	$	4,754	$	14,918	$	14,060