Goodwill (Summary of Goodwill) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)
Schedule Of Goodwill [Line Items]
Beginning Balance	$ 307,744
Goodwill, impairment loss	(304,123)
Acquisition of Gaiam, Inc. Branded Consumer Business [Member]
Schedule Of Goodwill [Line Items]
(Adjustment for) and acquisition of Gaiam Brand Holdco, LLC	$ (3,621)