Investments Equity Method Investments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Equity Method Investments and Joint Ventures [Abstract]
Variable Interest Entity, Qualitative or Quantitative Information, Date Involvement Began			Sep. 25, 2017
Variable Interest Entity, Financial or Other Support, Amount			$ 200,000
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage			66.70%
Variable Interest Entity, Measure of Activity, Other, Amount			$ 19,300
Variable Interest Entity, Measure of Activity, Purchases			14,700
Net (income) loss in earnings of equity method investment	$ 4,081	$ (2,971)	3,607	$ (2,971)
Management Fee Expense	800	$ 3,000	1,500	$ 3,000
Equity Method Investments	50,583		50,583		$ 31,151
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	$ 50,583		$ 50,583		$ 31,151