Real Estate Intangibles

12 Months Ended

Dec. 31, 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):


	December 31, 2021		December 31, 2020
Assets:
In place lease intangibles	$	1,681,533	$	1,406,705
Above market tenant leases	53,964		52,621
Lease commissions	54,131		40,704
Gross historical cost	1,789,628		1,500,030
Accumulated amortization	(1,286,259)		(1,177,513)
Net book value	$	503,369	$	322,517

Weighted-average amortization period in years	5.5		10.5

Liabilities:
Below market tenant leases	$	74,909	$	77,851


Accumulated amortization	(45,291)		(40,871)
Net book value	$	29,618	$	36,980

Weighted-average amortization period in years	8.2		8.3

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


	Year Ended December 31,
	2021		2020		2019
Rental income related to (above)/below market tenant leases, net	$	1,680	$	1,710	$	508
Amortization related to in place lease intangibles and lease commissions	(115,579)		(121,004)		(135,047)

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


	Assets		Liabilities
2022	$	168,534	$	7,374
2023	113,105		5,253
2024	56,699		3,118
2025	22,706		2,588
2026	23,009		2,075
Thereafter	119,316		9,210
Totals	$	503,369	$	29,618