Intangible Assets and Below Market Lease Liabilities - Scheduled Future Amortization (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Scheduled future amortization of intangible assets [Abstract]
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 231,347	$ 195,273
Scheduled future amortization of below market lease liabilites [Abstract]
Total scheduled future amortization of below market lease liabilities	(31,957)	$ (25,648)
Deferred Leasing Costs and Acquisition-Related Intangible Assets [Member]
Scheduled future amortization of intangible assets [Abstract]
2020	38,376
2021	33,581
2022	29,200
2023	25,683
2024	22,631
Thereafter	65,964
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 215,435
Weighted average remaining amortization periods for intangible assets and liabilities [Abstract]
Intangible assets, weighted average useful life (in years)	8 years 4 months 24 days
Lease Incentives [Member]
Scheduled future amortization of intangible assets [Abstract]
2020	$ 1,599
2021	1,353
2022	1,119
2023	1,040
2024	890
Thereafter	3,914
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 9,915
Weighted average remaining amortization periods for intangible assets and liabilities [Abstract]
Intangible assets, weighted average useful life (in years)	9 years 2 months 12 days
Acquisition-Related Intangible Assets (in Rental and Other Revenue) [Member]
Scheduled future amortization of intangible assets [Abstract]
2020	$ 1,095
2021	777
2022	608
2023	454
2024	380
Thereafter	2,173
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 5,487
Weighted average remaining amortization periods for intangible assets and liabilities [Abstract]
Intangible assets, weighted average useful life (in years)	9 years 4 months 24 days
Acquired intangible assets, weighted average useful life (in years)	14 years 4 months 24 days
Acquisition-Related Intangible Assets (Amortized in Depreciation and Amortization) [Member]
Weighted average remaining amortization periods for intangible assets and liabilities [Abstract]
Acquired intangible assets, weighted average useful life (in years)	14 years 8 months 12 days
Acquisition-Related Intangible Assets (in Rental Property and Other Expenses) [Member]
Scheduled future amortization of intangible assets [Abstract]
2020	$ 510
2021	0
2022	0
2023	0
2024	0
Thereafter	0
Deferred leasing costs, net/Total scheduled future amortization of intangible assets	$ 510
Weighted average remaining amortization periods for intangible assets and liabilities [Abstract]
Intangible assets, weighted average useful life (in years)	1 year
Acquisition-Related Below Market Lease Liabilities [Member]
Scheduled future amortization of below market lease liabilites [Abstract]
2020	$ (5,933)
2021	(5,033)
2022	(3,985)
2023	(3,607)
2024	(2,939)
Thereafter	(10,460)
Total scheduled future amortization of below market lease liabilities	$ (31,957)
Weighted average remaining amortization periods for intangible assets and liabilities [Abstract]
Below market lease liabilities, weighted average useful life (in years)	8 years 9 months 18 days
Assumed finite-lived below market lease liabilities, weighted average useful life (in years)	14 years 3 months 18 days