Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2014

Fair Value Measurements [Abstract]

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

	Assets and Liabilities at Fair Value as of June 30, 2014
	Level 1		Level 2		Level 3		Total
	(in thousands)
Assets
Cash and cash equivalents	$	27,725	$	—	$	—	$	27,725
Short-term investments	50,767		552		—		51,319
Total cash and cash equivalents and investments	$	78,492	$	552	$	—	$	79,044
Liabilities
Other long-term liabilities	$	—	$	—	$	29,300	$	29,300
Total liabilities	$	—	$	—	$	29,300	$	29,300

	Assets and Liabilities at Fair Value as of December 31, 2013
	Level 1		Level 2		Level 3		Total
	(in thousands)
Assets
Cash and cash equivalents	$	37,499	$	—	$	—	$	37,499
Short-term investments	91,077		552		—		91,629
Total cash and cash equivalents and investments	$	128,576	$	552	$	—	$	129,128
Liabilities
Other long-term liabilities	$	—	$	—	$	27,710	$	27,710
Total liabilities	$	—	$	—	$	27,710	$	27,710

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

	Other Long-term Liabilities
	(in thousands)
Balance at December 31, 2013	$	27,710
Change in valuation of purchase consideration payable to former Symphony Icon stockholders	1,590
Balance at June 30, 2014	$	29,300
Balance at December 31, 2012	$	29,920
Change in valuation of purchase consideration payable to former Symphony Icon stockholders	1,741
Balance at June 30, 2013	$	31,661