Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2013

Fair Value Measurements [Abstract]

Fair Value, by Balance Sheet Grouping [Table Text Block]

	Assets and Liabilities at Fair Value as of September 30, 2013
	Level 1		Level 2		Level 3		Total
	(in thousands)
Assets
Cash and cash equivalents	$	19,581	$	—	$	—	$	19,581
Short-term investments	131,078		551		—		131,629
Total cash and cash equivalents and investments	$	150,659	$	551	$	—	$	151,210
Liabilities
Other long-term liabilities	$	—	$	—	$	32,999	$	32,999
Total liabilities	$	—	$	—	$	32,999	$	32,999

	Assets and Liabilities at Fair Value as of December 31, 2012
	Level 1		Level 2		Level 3		Total
	(in thousands)
Assets
Cash and cash equivalents	$	30,423	$	—	$	—	$	30,423
Short-term investments	192,234		551		—		192,785
Total cash and cash equivalents and investments	$	222,657	$	551	$	—	$	223,208
Liabilities
Other long-term liabilities	$	—	$	—	$	29,920	$	29,920
Total liabilities	$	—	$	—	$	29,920	$	29,920

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

	Other Long-term Liabilities
	(in thousands)
Balance at December 31, 2012	$	29,920
Change in valuation of purchase consideration payable to former Symphony Icon stockholders	3,079
Balance at September 30, 2013	$	32,999
Balance at December 31, 2011	$	55,033
Change in valuation of purchase consideration payable to former Symphony Icon stockholders	10,087
Payment of base payment obligation with common stock	(35,000		)
Balance at September 30, 2012	$	30,120