Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Taxes [Line Items]
Valuation allowance increase (decrease) in amount	$ 7,800,000	$ (27,600,000)	$ (2,100,000)
Net operating loss carryforwards related to stock option	10,700,000
Alternative Minimum Tax Credit [Member]
Income Taxes [Line Items]
Tax credit carryforward amount	10,000
Federal Tax Authority [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	57,000,000
Operating loss carryforwards, expiration dates	2021 through 2030
Federal Tax Authority [Member] | Research And Development Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Tax credit carryforward amount	6,400,000
Tax credit carryforward expiration period	2012 through 2030
State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	101,000,000
Operating loss carryforwards, expiration dates	2017 through 2030
State and Local Jurisdiction [Member] | Research And Development Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Tax credit carryforward amount	1,100,000
Foreign Tax Authority [Member]
Income Taxes [Line Items]
Tax credit carryforward amount	$ 200,000
Tax credit carryforward expiration period	begin to expire in 2014