Intangible Assets and Below Market Lease Liabilities - Scheduled Future Amortization (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Scheduled future amortization of intangible assets [Abstract]
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 209,329	$ 231,347
Scheduled future amortization of below market lease liabilites [Abstract]
Total scheduled future amortization of below market lease liabilities	(25,910)	$ (31,957)
Deferred Leasing Costs and Acquisition-Related Intangible Assets [Member]
Scheduled future amortization of intangible assets [Abstract]
2021	34,063
2022	30,011
2023	26,496
2024	23,348
2025	19,224
Thereafter	60,979
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 194,121
Weighted average remaining amortization periods for intangible assets and liabilities [Abstract]
Intangible assets, weighted average useful life (in years)	8 years 3 months 18 days
Lease Incentives [Member]
Scheduled future amortization of intangible assets [Abstract]
2021	$ 1,563
2022	1,353
2023	1,279
2024	1,133
2025	1,064
Thereafter	4,523
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 10,915
Weighted average remaining amortization periods for intangible assets and liabilities [Abstract]
Intangible assets, weighted average useful life (in years)	9 years 6 months
Acquisition-Related Intangible Assets (in Rental and Other Revenue) [Member]
Scheduled future amortization of intangible assets [Abstract]
2021	$ 711
2022	601
2023	447
2024	373
2025	342
Thereafter	1,819
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 4,293
Weighted average remaining amortization periods for intangible assets and liabilities [Abstract]
Intangible assets, weighted average useful life (in years)	9 years 8 months 12 days
Acquisition-Related Below Market Lease Liabilities [Member]
Scheduled future amortization of below market lease liabilites [Abstract]
2021	$ (4,958)
2022	(3,977)
2023	(3,600)
2024	(2,932)
2025	(1,673)
Thereafter	(8,770)
Total scheduled future amortization of below market lease liabilities	$ (25,910)
Weighted average remaining amortization periods for intangible assets and liabilities [Abstract]
Below market lease liabilities, weighted average useful life (in years)	8 years 7 months 6 days