Rental Income - Future Minimum Rental Payments prior to Adoption (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Consolidated properties
Property Subject to or Available for Operating Lease [Line Items]
2019	$ 830,336
2020	765,610
2021	625,956
2022	562,250
2023	500,499
Thereafter	3,272,014
Total future minimum payments receivable	6,556,665
Unconsolidated properties
Property Subject to or Available for Operating Lease [Line Items]
2019	348,060
2020	375,228
2021	380,886
2022	348,222
2023	333,501
Thereafter	2,098,995
Total future minimum payments receivable	$ 3,884,892