Summary of Significant Accounting Policies - Recently Adopted Accounting Pronouncements (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets	$ 850	$ 217
Convertible notes balance	229,782	209,754
Accounting Standards Update 201503 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other assets	(4,200)	(5,100)
Convertible notes balance	$ (4,200)	$ (5,100)