Income Taxes - Income Tax Provision/(Benefit) and Deferred Income Taxes (Details Textual) (USD $)	3 Months Ended		12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Line Items]
Deferred state income tax provision, Impact of state income tax law change					$ (3,100,000)
Undistributed Earnings of Foreign Subsidiaries			33,000,000
2012 R&D tax credits recorded in 2013				6,000,000
Incremental R&D tax credits related to Prior Periods				5,000,000
Reduction of Certain Tax Allowances				6,000,000
Deferred income tax assets benefits percentage			100.00%
Valuation allowance			20,507,000	17,741,000
Deferred income tax assets related to state income tax jurisdictions			2,700,000
Deferred income tax assets related to foreign income tax jurisdictions			35,600,000
Valuation allowance against deferred tax assets related to state jurisdictions			2,500,000
Valuation allowance against deferred tax assets related to foreign jurisdictions			18,000,000
Cash payments related to the deferred income tax liabilities associated with the 2004 Convertible Debt Securities	6,000,000	6,000,000	5,600,000
Deferred income tax liability related to debt securities repurchased			23,000,000
Payment period of deferred income tax liabilities associated with Convertible Debt			4 years
Domestic Country
Income Taxes [Line Items]
Valuation allowance			0
Operating loss carryforward			51,000,000	51,000,000
Operating Loss Carryforwards, Expiration Dates			begin to expire in 2019 and can be utilized through 2030
Interest rate used for tax deduction					9.09%
State And Local Jurisdiction
Income Taxes [Line Items]
Operating loss carryforward			63,000,000	50,000,000
Operating Loss Carryforwards, Expiration Dates			will expire beginning in 2015 and end in 2035
Foreign Country
Income Taxes [Line Items]
Operating loss carryforward			$ 96,000,000	$ 90,000,000
Operating Loss Carryforwards, Expiration Dates			2017