Debt - Master Trust Notes - Narrative (Details)
6 Months Ended
May 21, 2018
USD ($)
Feb. 02, 2018
USD ($)
Jan. 23, 2018
USD ($)
Jun. 30, 2018
USD ($)
Property
Dec. 31, 2017
Master Trust 2013 Notes          
Debt Instrument [Line Items]          
Number of properties securing borrowings | Property       269  
Master Trust Notes | Master Trust 2014 Series 2017-1          
Debt Instrument [Line Items]          
Aggregate principal amount of debt     $ 674,200,000.0    
Stated interest rate     5.49%   6.35%
Proceeds from issuance of debt     $ 8,200,000    
Master Trust Notes | Master Trust 2014, Series 2014-2          
Debt Instrument [Line Items]          
Debt extinguished   $ 11,600,000      
Master Trust Notes | Series 2013-1 Class A          
Debt Instrument [Line Items]          
Debt extinguished $ 123,100,000        
Make-whole payment in debt extinguishment $ 0        
Master Trust Notes | Series 2013-2, Class A          
Debt Instrument [Line Items]          
Stated interest rate       5.269%  
Debt extinguished       $ 15,200,000  
Make-whole payment in debt extinguishment       $ 934,000