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Restructuring, Impairment and Other Costs (Details Textual) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
	Mar. 26, 2018	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring, impairment and other costs (reversal)		$ 0	$ 600	$ 0	$ (639)	$ 0
Restructuring charges		$ 0		$ 0	639	$ 0
Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges					$ 0
Craig's Separation Agreement \| Employee Severance
Restructuring Cost and Reserve [Line Items]
Term for base salary continuation					12 months
Time-Vested Restricted Stock
Restructuring Cost and Reserve [Line Items]
Accelerated vesting, number	5,488
Performance-Vested Restricted Stock
Restructuring Cost and Reserve [Line Items]
Accelerated vesting, number	5,488
Salaries, Wages and Employee Benefits \| Craig's Separation Agreement \| Employee Severance
Restructuring Cost and Reserve [Line Items]
Severance costs					$ 400
Restructuring charges					$ 700