Income Taxes - Income Tax Provision/(Benefit) and Deferred Income Taxes (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2011
Income Taxes [Line Items]
Undistributed Earnings of Foreign Subsidiaries	$ 43,000,000
Deferred income tax assets benefits percentage	100.00%
Valuation allowance	$ 17,750,000	$ 17,414,000
Deferred income tax assets	65,690,000	77,270,000
Cash payments related to the deferred income tax liabilities associated with the 2004 Convertible Debt Securities	5,600,000	5,600,000	$ 6,000,000
Balance owed U.S. Tax Authorities related to deferred income tax liabilities associated with the 2004 Convertible Debt Securities repurchased	$ 11,000,000
Payment period of balance owed U.S. Tax Authorities related to deferred income tax liabilities associated with the 2004 Convertible Debt Securities repurchased	2 years
Domestic Country
Income Taxes [Line Items]
Valuation allowance	$ 0
Operating loss carryforward	$ 45,000,000	50,000,000
Operating Loss Carryforwards, Expiration Dates	begin to expire in 2023 and can be utilized through 2030
Interest rate used for tax deduction			9.09%
State And Local Jurisdiction
Income Taxes [Line Items]
Valuation allowance	$ 2,500,000
Deferred income tax assets	2,600,000
Operating loss carryforward	$ 63,000,000	63,000,000
Operating Loss Carryforwards, Expiration Dates	will expire beginning in 2017 and end in 2037
Foreign Country
Income Taxes [Line Items]
Valuation allowance	$ 15,400,000
Deferred income tax assets	27,600,000
Operating loss carryforward	$ 87,000,000	$ 91,000,000
Operating Loss Carryforwards, Expiration Dates	2017