Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Share-based Compensation [Abstract]

Finite-lived Intangible Assets Amortization Expense [Table Text Block]

Estimated future amortization expense for intangible assets as of December 31, 2017 is as follows:

	For the Year Ending December 31
	(in thousands)
2018	$	1,766
2019	1,766
2020	1,766
2021	1,766
2022	1,766
Thereafter	14,417
	$	23,247

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

	Expected Volatility	Risk-free Interest Rate	Expected Term	Dividend Rate
December 31, 2017:
Employees	61%	1.7%	4	0	%
Officers and non-employee directors	70%	2.2%	8	0	%
December 31, 2016:
Employees	63%	1.1%	4	0	%
Officers and non-employee directors	83%	1.6%	8	0	%
December 31, 2015:
Employees	64%	1.2%	4	0	%
Officers and non-employee directors	81%	1.8%	8	0	%