Intangible Assets and Below Market Lease Liabilities - Scheduled Future Amortization (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Scheduled future amortization of intangible assets [Abstract]
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 267,405	$ 209,329
Scheduled future amortization of below market lease liabilities [Abstract]
Total scheduled future amortization of acquisition-related below market lease liabilities	(30,204)	$ (25,910)
Deferred Leasing Costs and Acquisition-Related Intangible Assets (in Depreciation and Amortization) [Member]
Scheduled future amortization of intangible assets [Abstract]
October 1 through December 31, 2021	11,669
2022	42,867
2023	38,076
2024	33,874
2025	26,988
Thereafter	86,170
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 239,644
Weighted average remaining amortization periods for intangible assets and below market lease liabilities [Abstract]
Finite-lived intangible assets, average useful life (in years)	7 years 9 months 18 days
Acquired intangible assets, weighted average useful life (in years)	7 years 2 months 12 days
Lease Incentives (in Rental and Other Revenues) [Member]
Scheduled future amortization of intangible assets [Abstract]
October 1 through December 31, 2021	$ 381
2022	1,484
2023	1,414
2024	1,269
2025	1,195
Thereafter	5,056
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 10,799
Weighted average remaining amortization periods for intangible assets and below market lease liabilities [Abstract]
Finite-lived intangible assets, average useful life (in years)	8 years 9 months 18 days
Acquisition-Related Intangible Assets (in Rental and Other Revenues) [Member]
Scheduled future amortization of intangible assets [Abstract]
October 1 through December 31, 2021	$ 777
2022	2,986
2023	2,829
2024	2,573
2025	1,667
Thereafter	6,130
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 16,962
Weighted average remaining amortization periods for intangible assets and below market lease liabilities [Abstract]
Finite-lived intangible assets, average useful life (in years)	7 years 9 months 18 days
Acquired intangible assets, weighted average useful life (in years)	7 years 3 months 18 days
Acquisition-Related Below Market Lease Liabilities (in Rental and Other Revenues) [Member]
Scheduled future amortization of below market lease liabilities [Abstract]
October 1 through December 31, 2021	$ (1,420)
2022	(5,290)
2023	(4,868)
2024	(4,129)
2025	(2,594)
Thereafter	(11,903)
Total scheduled future amortization of acquisition-related below market lease liabilities	$ (30,204)
Weighted average remaining amortization periods for intangible assets and below market lease liabilities [Abstract]
Finite-lived below market lease liabilities, average useful life (in years)	8 years 4 months 24 days
Assumed finite-lived below market lease liabilities, weighted average useful life (in years)	8 years 2 months 12 days