Real Estate Intangibles (Tables)

9 Months Ended

Sep. 30, 2018

Intangible Assets, Net (Excluding Goodwill) [Abstract]

Summary of real estate intangibles excluding those classified as held for sale

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

	September 30, 2018			December 31, 2017
Assets:
In place lease intangibles	$	1,398,850		$	1,352,139
Above market tenant leases	59,011			58,443
Below market ground leases	65,022			58,784
Lease commissions	39,767			33,105
Gross historical cost	1,562,650			1,502,471
Accumulated amortization	(1,190,035		)	(1,125,437		)
Net book value	$	372,615		$	377,034
Weighted-average amortization period in years	16.0			15.1
Liabilities:
Below market tenant leases	$	71,566		$	60,430
Above market ground leases	8,540			8,540
Gross historical cost	80,106			68,970
Accumulated amortization	(42,834		)	(39,629		)
Net book value	$	37,272		$	29,341
Weighted-average amortization period in years	16.1			20.1

Schedule of Real Estate Intangible Amortization

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

	Three Months Ended September 30,						Nine Months Ended September 30,
	2018			2017			2018			2017
Rental income related to above/below market tenant leases, net	$	(294	)	$	173		$	(978	)	$	745
Property operating expenses related to above/below market ground leases, net	(327		)	(306		)	(1,006		)	(925		)
Depreciation and amortization related to in place lease intangibles and lease commissions	(31,455		)	(34,270		)	(97,479		)	(109,011		)

Schedule of future amortization expense

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

	Assets		Liabilities
2018	$	32,456	$	1,433
2019	87,011		5,437
2020	57,221		4,938
2021	24,300		4,444
2022	19,325		3,971
Thereafter	152,302		17,049
Total	$	372,615	$	37,272