Real Estate Intangibles

9 Months Ended

Sep. 30, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

The following is a summary of our real estate intangibles, excluding those related to ground leases or classified as held for sale, as of the dates indicated (dollars in thousands):


	September 30, 2021		December 31, 2020
Assets:
In place lease intangibles	$	1,549,294	$	1,406,705
Above market tenant leases	54,542		52,621
Lease commissions	49,579		40,704
Gross historical cost	1,653,415		1,500,030
Accumulated amortization	(1,249,032)		(1,177,513)
Net book value	$	404,383	$	322,517

Weighted-average amortization period in years	8.3		10.5

Liabilities:
Below market tenant leases	$	75,083	$	77,851
Accumulated amortization	(43,484)		(40,871)
Net book value	$	31,599	$	36,980

Weighted-average amortization period in years	8.4		8.3

The following is a summary of real estate intangible amortization income (expense) for the periods presented (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Rental income related to (above)/below market tenant leases, net	$	384	$	327	$	1,241	$	1,252
Amortization related to in place lease intangibles and lease commissions	(32,872)		(28,948)		(76,083)		(98,241)

The future estimated aggregate amortization of intangible assets and liabilities is as follows for the periods presented (in thousands):


	Assets		Liabilities
2021	$	36,111	$	1,962
2022	112,533		7,311
2023	70,483		5,179
2024	33,451		3,053
2025	23,099		2,524
Thereafter	128,706		11,570
Total	$	404,383	$	31,599