Income Taxes (Details 5) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Operating loss carryforwards and tax credit carryforwards
Operating Loss Carryforwards	$ 61,636
Tax Credit Carryforwards	63,488
Expiring in 2012 [Member]
Operating loss carryforwards and tax credit carryforwards
Operating Loss Carryforwards	453
Tax Credit Carryforwards	3,676
Expiring in 2013-2017 [Member]
Operating loss carryforwards and tax credit carryforwards
Operating Loss Carryforwards	13,252
Tax Credit Carryforwards	36,800
Expiring in 2018-2022 [Member]
Operating loss carryforwards and tax credit carryforwards
Operating Loss Carryforwards	8,680
Tax Credit Carryforwards	9,467
Expiring in 2023-2027 [Member]
Operating loss carryforwards and tax credit carryforwards
Operating Loss Carryforwards	5,281
Tax Credit Carryforwards	8,514
Expiring in 2028-2032 [Member]
Operating loss carryforwards and tax credit carryforwards
Operating Loss Carryforwards	2,095
Tax Credit Carryforwards	2,606
Expiring in 2033-Indefinitely [Member]
Operating loss carryforwards and tax credit carryforwards
Operating Loss Carryforwards	31,875
Tax Credit Carryforwards	$ 2,425