Debt - Schedule of Debt Maturities (Footnote) (Details)
$ in Thousands
3 Months Ended
Mar. 31, 2018
USD ($)
Loan
Mar. 31, 2017
USD ($)
Debt Instrument [Line Items]    
Capitalized interest $ 1,062 $ 714
CMBS | CMBS Loans    
Debt Instrument [Line Items]    
Debt default amount 31,400  
Capitalized interest $ 10,300  
Revolving Credit Facility    
Debt Instrument [Line Items]    
Extension option, term 1 year  
Discontinued Operations, Disposed of by Sale | CMBS Loans    
Debt Instrument [Line Items]    
Number of loans in default | Loan 3