Rental Property - Deferred Leasing Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Deferred leasing intangibles, gross	$ 743,565		$ 743,565		$ 757,807
Deferred leasing intangibles assets, accumulated amortization	(260,893)		(260,893)		(258,005)
Deferred leasing intangibles, net	482,672		482,672		499,802
Below market lease, gross	50,439		50,439		48,521
Below market lease, accumulated amortization	(17,510)		(17,510)		(15,759)
Below market lease, net	32,929		32,929		32,762
Net decrease to rental income related to above and below market lease amortization	330	$ 1,174	1,810	$ 2,164
Above market leases
Finite-Lived Intangible Assets [Line Items]
Deferred leasing intangibles, gross	86,466		86,466		92,125
Deferred leasing intangibles assets, accumulated amortization	(31,194)		(31,194)		(33,629)
Deferred leasing intangibles, net	55,272		55,272		58,496
Other intangible lease assets
Finite-Lived Intangible Assets [Line Items]
Deferred leasing intangibles, gross	657,099		657,099		665,682
Deferred leasing intangibles assets, accumulated amortization	(229,699)		(229,699)		(224,376)
Deferred leasing intangibles, net	427,400		427,400		$ 441,306
Amortization expense related to other intangible lease assets	21,422	$ 21,076	43,869	$ 41,378
Estimated Net Amortization of In-Place Leases, Leasing Commissions and Tenant Relationships
2021	38,884		38,884
Finite-Lived Intangible Asset, Expected Amortization, Year One	68,917		68,917
2022	60,313		60,313
2023	51,203		51,203
2024	43,445		43,445
Net decrease to rental income related to above and below market lease amortization
Estimated Net Amortization of In-Place Leases, Leasing Commissions and Tenant Relationships
2021	283		283
Finite-Lived Intangible Asset, Expected Amortization, Year One	327		327
2022	820		820
2023	1,286		1,286
2024	$ 1,164		$ 1,164

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