Intangibles - Gross Carrying Amount and Accumulated Amortization of Intangible Assets and Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Intangible assets:
Total intangible assets	$ 395,896	$ 403,092
Accumulated amortization:
Total accumulated amortization	(147,306)	(110,434)
Intangible assets, net	248,590	292,658
Intangible liabilities:
Below-market lease intangibles	62,338	62,199
Above-market ground lease intangibles		4,657
Total intangible liabilities	62,338	66,856
Accumulated amortization:
Below-market lease amortization	(14,074)	(11,132)
Above-market ground lease amortization		(15)
Total accumulated amortization	(14,074)	(11,147)
Intangible liabilities, net	48,264	55,709
In-place Lease Intangibles [Member]
Intangible assets:
Total intangible assets	368,599	354,261
Accumulated amortization:
Total accumulated amortization	(140,752)	(104,745)
Intangible assets, net	227,847
Above-market Lease Intangibles [Member]
Intangible assets:
Total intangible assets	21,621	21,626
Accumulated amortization:
Total accumulated amortization	(6,265)	(4,903)
Intangible assets, net	15,356
Prepaid Ground Lease Intangibles [Member]
Intangible assets:
Total intangible assets		16,114
Accumulated amortization:
Total accumulated amortization		(378)
Below-market Ground Lease Intangibles [Member]
Intangible assets:
Total intangible assets		5,415
Accumulated amortization:
Total accumulated amortization		(162)
Other Intangible Assets [Member]
Intangible assets:
Total intangible assets	5,676	5,676
Accumulated amortization:
Total accumulated amortization	$ (289)	$ (246)