Fair Values of Assets and Liabilities Summary of Fair Value Hierarchy for Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Nov. 30, 2005	May 31, 2005
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Line of Credit	$ 90,716	$ 83,399
Amortizing debt facilities	54,873	58,190
Notes Payable, Related Parties	40,000	40,000
Convertible Debt, Fair Value Disclosures	60,937	60,791
Liabilities carried at fair value
Notes payable associated with structured financings, at fair value	11,131	12,276
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Line of Credit	0	0
Amortizing debt facilities	0	0
Notes Payable, Related Parties	0	0
Convertible Debt, Fair Value Disclosures	0	0
Liabilities carried at fair value
Notes payable associated with structured financings, at fair value	0	0
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Line of Credit	0	0
Amortizing debt facilities	0	0
Notes Payable, Related Parties	0	0
Convertible Debt, Fair Value Disclosures	42,816	40,609
Liabilities carried at fair value
Notes payable associated with structured financings, at fair value	0	0
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Line of Credit	90,716	83,399
Amortizing debt facilities	54,873	58,190
Notes Payable, Related Parties	40,000	40,000
Convertible Debt, Fair Value Disclosures	0	0
Liabilities carried at fair value
Notes payable associated with structured financings, at fair value	$ 11,131	$ 12,276
Five Point Eight Seven Five Percent Convertible Senior Notes Due Two Thousand Thirty Five [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.875%	5.875%