Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets	$ 51,744
Operating lease liability	$ 56,911
Discount rate, present value of future revenue	10.00%
Impairment charges		$ 0
Capitalized general and administrative costs	$ 8,400	7,300
Interest costs capitalized	$ 1,600	$ 1,900
Employee Stock Option
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Antidilutive securities (in shares)	2,773,848
Restricted Stock Units (RSUs)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Antidilutive securities (in shares)	352,716
Restricted Stock
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Antidilutive securities (in shares)	751,243
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets	$ 62,300
Operating lease liability	$ 62,300