Debt - Master Trust Notes - Narrative (Details)
3 Months Ended
Mar. 31, 2017
Subsidiary
Property
trust
Debt Instrument [Line Items]  
Number of securitization trusts within program | trust 2
Master Trust 2014 notes  
Debt Instrument [Line Items]  
Number of properties securing borrowings 847
Debt issued by, number of subsidiaries | Subsidiary 5
Master Trust 2013 notes  
Debt Instrument [Line Items]  
Number of properties securing borrowings 304