Income Taxes (Tables)

12 Months Ended

Dec. 31, 2012

Income Taxes [Abstract]

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	As of December 31,
	2012			2011
	(in thousands)
Deferred tax assets:
Net operating loss carryforwards	$	216,579		$	195,810
Research and development tax credits	32,066			34,611
Capitalized research and development	71,839			60,938
Stock-based compensation	12,972			11,843
Deferred revenue	4,906			5,008
Other	10,429			7,126
Total deferred tax assets	348,791			315,336
Deferred tax liabilities:
Deferred tax liability related to acquisition of Symphony Icon	(18,745		)	(18,745		)
Other	(340		)	(343		)
Total deferred tax liabilities	(19,085		)	(19,088		)
Less: valuation allowance	(348,451		)	(314,993		)
Net deferred tax liabilities	$	(18,745	)	$	(18,745	)