Income Taxes Components of Deferred Tax asset/ liability (Textual) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Components of Deferred Tax Assets and Liabilities [Line Items]
Percentage of deferred tax assets on which valuation allowance is created	100.00%
State and Local Jurisdiction [Member]
Components of Deferred Tax Assets and Liabilities [Line Items]
Operating Loss Carryforwards	$ 75.0
State and Local Jurisdiction [Member] | Research Tax Credit Carryforward [Member]
Components of Deferred Tax Assets and Liabilities [Line Items]
Tax Credit Carryforward, Amount	14.4
Domestic Tax Authority [Member]
Components of Deferred Tax Assets and Liabilities [Line Items]
Operating Loss Carryforwards	184.4
Operating Loss Carryforwards, Expiration Dates	2031
Domestic Tax Authority [Member] | Research Tax Credit Carryforward [Member]
Components of Deferred Tax Assets and Liabilities [Line Items]
Tax Credit Carryforward, Amount	$ 10.3
Tax Credit Carryforward, Expiration Date	2032