Fair Value Measurements (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures	$ 0
Business Combination, Contingent Consideration, Liability	320,973	$ 347,104
Fixed payments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration, Liability	10,040	$ 40,370
Common Stock [Member] | Common Class A [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stock Issued During Period, Value, New Issues	$ 5,368
Stock Issued During Period, Shares, New Issues	227,437
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures	$ 956
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures	79,278
Contingent Consideration, Liability Settlements [Domain]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stock Issued During Period, Value, New Issues	$ 5,368