Investments in Affiliates (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($)
April 2017 [Member]
Schedule of Equity Method Investments [Line Items]
Capital Contribution	$ 240
Resulting Class A Units (%)	2.00%
Resulting Sharing %	2.98%
August 2017 [Member]
Schedule of Equity Method Investments [Line Items]
Capital Contribution	$ 3,710
Resulting Class A Units (%)	15.20%
Resulting Sharing %	16.04%
September 2017 [Member]
Schedule of Equity Method Investments [Line Items]
Capital Contribution	$ 2,920
Resulting Class A Units (%)	18.55%
Resulting Sharing %	19.37%
November 2017 [Member]
Schedule of Equity Method Investments [Line Items]
Capital Contribution	Warrant exercise
Resulting Class A Units (%)	26.50%
Resulting Sharing %	27.24%