Lease Intangible Assets and Liabilities - Summary of Lease Intangible Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross Asset	$ 509,635	$ 563,346
Accumulated Amortization	(258,332)	(253,248)
Balance	251,303	310,098
In-Place Leases, Net [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Asset	489,593	542,655
Accumulated Amortization	(254,180)	(249,569)
Balance	235,413	293,086
Below-Market Ground Leases, Net [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Asset	11,766	11,766
Accumulated Amortization	(609)	(508)
Balance	11,157	11,258
Above-Market Leases, Net [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Asset	8,276	8,925
Accumulated Amortization	(3,543)	(3,171)
Balance	$ 4,733	$ 5,754

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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