Intangibles (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Intangible assets:
Acquired lease intangibles	$ 1,230,886	$ 1,308,077
Goodwill	1,051,650	1,051,161
Accumulated amortization	(941,462)	(922,668)
Net intangible assets	$ 1,376,944	$ 1,472,408
Remaining Weighted Average Amortization Period in Years	10 years 3 months 18 days	10 years 2 months 12 days
Intangible liabilities:
Below market lease intangibles	$ 339,265	$ 349,357
Other lease intangibles	13,498	13,498
Accumulated amortization	(212,655)	(203,834)
Purchase option intangibles	3,568	3,568
Net intangible liabilities	$ 143,676	$ 162,589
Below market leases, remaining weighted average amortization period	14 years 3 months 18 days	14 years 6 months
Net intangible liabilities, remaining weighted average amortization period	14 years 3 months 18 days	14 years 6 months
Intangibles
Net amortization expense	$ 45,700	$ 59,200	$ 49,200
2021	50,421
2022	42,787
2023	31,343
2024	16,932
2025	8,977
Above Market Lease Intangibles
Intangible assets:
Acquired lease intangibles	$ 140,096	$ 145,891
Remaining Weighted Average Amortization Period in Years	6 years 4 months 24 days	6 years 10 months 24 days
In-Place and Other Lease Intangibles
Intangible assets:
Acquired lease intangibles	$ 1,090,790	$ 1,162,187
Remaining Weighted Average Amortization Period in Years	10 years 8 months 12 days	10 years 7 months 6 days
Other Intangibles
Intangible assets:
Other intangibles	$ 35,870	$ 35,837
Remaining Weighted Average Amortization Period in Years	10 years	10 years 10 months 24 days