Leases (Schedule of Future Minimum Rent from Lessee for Ground Leases) (Details) - USD ($)
$ in Thousands
Mar. 31, 2019
Dec. 31, 2018
Leases [Abstract]    
Nine months ending December 31, 2019 $ 402  
2020 536  
2021 536  
2022 536  
2023 536  
Thereafter 70,165  
Total undiscounted rental payments 72,711  
Less imputed interest (63,961)  
Total operating lease liabilities $ 8,750 $ 0