Organization - Narrative (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]    
Transaction costs $ 3,932 $ 0
General Partner    
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]    
Ownership of operating partnership 1.00%  
Limited Partner    
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]    
Ownership of operating partnership 99.00%