Debt (Tables)

3 Months Ended

Mar. 31, 2018

Debt

Schedule of components of convertible notes

The components of the convertible notes are as follows (in thousands):

				Carrying Amount,
	Interest Rates			March 31,		December 31,
Debt	March 31, 2018		Maturities	2018		2017
0.375% Convertible Senior Notes due 2018	0.375	%	2018	$	7,460		7,393
1.25% Convertible Senior Notes due 2020	1.25	%	2020		16,811		16,608
					24,271		24,001
Less current portion					7,460		7,393
				$	16,811	$	16,608

Schedule of carrying amount and fair value of convertible notes

The carrying amount and fair value of our convertible notes are as follows (in thousands):

	March 31, 2018				December 31, 2017
	2018				2017
	Carrying				Carrying
	Amount		Fair Value		Amount		Fair Value
0.375% Convertible Senior Notes due 2018	$	7,460	$	12,389	$	7,393	$	14,129
1.25% Convertible Senior Notes due 2020		16,811		31,219		16,608		35,431
	$	24,271	$	43,608	$	24,001	$	49,560