Leases - Summary of Lease Income Types Relating to Lease Payments Along With the Total Other Rental Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating Leased Assets [Line Items]
Total lease revenue	$ 2,514,187	$ 2,608,103
Rental income	2,571,705	2,700,691	$ 2,577,681
Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	2,461,351	2,534,779
Non-Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	52,836	73,324
Residential and Non-Residential Rent [Member]
Operating Leased Assets [Line Items]
Total lease revenue	2,388,441	2,486,189
Residential and Non-Residential Rent [Member] | Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	2,336,778	2,414,201
Residential and Non-Residential Rent [Member] | Non-Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	51,663	71,988
Utility Recoveries (RUBS Income) [Member]
Operating Leased Assets [Line Items]
Total lease revenue	71,376	68,576
Utility Recoveries (RUBS Income) [Member] | Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	70,699	67,659
Utility Recoveries (RUBS Income) [Member] | Non-Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	677	917
Parking Rent [Member]
Operating Leased Assets [Line Items]
Total lease revenue	39,155	37,905
Parking Rent [Member] | Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	38,743	37,557
Parking Rent [Member] | Non-Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	412	348
Storage Rent [Member]
Operating Leased Assets [Line Items]
Total lease revenue	3,758	3,816
Storage Rent [Member] | Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	3,674	3,745
Storage Rent [Member] | Non-Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	84	71
Pet Rent [Member]
Operating Leased Assets [Line Items]
Total lease revenue	11,457	11,617
Pet Rent [Member] | Residential Leases [Member]
Operating Leased Assets [Line Items]
Total lease revenue	11,457	11,617
Parking Revenue
Operating Leased Assets [Line Items]
Rental income	22,210	28,272
Other Revenue
Operating Leased Assets [Line Items]
Rental income	35,308	64,316
Other Rental Income [Member]
Operating Leased Assets [Line Items]
Rental income	$ 57,518	$ 92,588