Summary of Significant Accounting Policies (Schedule of Adoption of New Accounting Pronouncements) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenues	$ 260,178	$ 199,427
Cost of inventory sold	(75,791)	(63,401)
Costs of services	(36,657)	(24,340)
Gross revenue, net of expenses		111,686
As Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenues		124,499
Costs of services		(12,813)
Gross revenue, net of expenses		111,686
New Revenue Standard Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenues		74,928
Cost of inventory sold		(63,401)
Costs of services		(11,527)
Revenue from Inventory Sales [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenues	84,162	76,048
Revenue from Inventory Sales [Member] | New Revenue Standard Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenues		76,048
Service Revenues [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenues	$ 176,016	123,379
Service Revenues [Member] | New Revenue Standard Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenues		$ (1,120)