Income Taxes (Deferred Tax Assets (Liabilities)) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Income Taxes [Abstract]
Net operating losses	$ 122,731	$ 116,492
Research tax credits	5,693	5,904
Other	7,326	3,974
Total deferred tax assets	135,750	126,370
Other	(335)	(350)
Total deferred tax liabilities	(335)	(350)
Net deferred tax assets	135,415	126,020
Less valuation allowance	(135,415)	(126,020)
Deferred tax assets, net