Commitments and Contingencies - Minimum Rental Commitments Less Imputed Interest (Details)
$ in Thousands
Sep. 30, 2019
USD ($)
Lessee, Lease, Description [Line Items]  
Remainder of 2019 $ 312
2020 1,262
2021 1,274
2022 1,206
2023 1,197
Thereafter 4,024
Total 9,275
Less: imputed interest (1,600)
Total operating lease liabilities 7,675
Ground Leases  
Lessee, Lease, Description [Line Items]  
Remainder of 2019 63
2020 253
2021 250
2022 166
2023 142
Thereafter 675
Total 1,549
Less: imputed interest (278)
Total operating lease liabilities 1,271
Office Leases  
Lessee, Lease, Description [Line Items]  
Remainder of 2019 249
2020 1,009
2021 1,024
2022 1,040
2023 1,055
Thereafter 3,349
Total 7,726
Less: imputed interest (1,322)
Total operating lease liabilities $ 6,404