Debt Obligation (Tables)

3 Months Ended

Mar. 31, 2012

Debt Obligations [Abstract]

Schedule of carrying value of convertible senior notes [Table Text Block]

The following table reflects the net carrying value of the Notes as of March 31, 2012:

	March 31, 2012			December 31, 2011
Convertible senior notes	$	60,000		$	60,000
Less: Unamortized interest discount	(12,871		)	(13,476		)
Net carrying value of convertible senior notes	$	47,129		$	46,524

Schedule of interest cost recognized on convertible senior notes [Table Text Block]

The following table presents the amount of interest cost recognized relating to the Notes during the three months endedMarch 31, 2012.

	March 31, 2012
Contractual interest coupon	$	563
Amortization of interest discount	605
Amortization of debt issuance costs	59
Total interest cost recognized	$	1,227