Intangibles - Carrying Amount of Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Cost	$ 301,462	$ 205,168
Accumulated Amortization	(63,177)	(30,008)
Net	238,285	175,160
Liability
Cost	11,642	6,769
Accumulated Amortization	(2,389)	(819)
Net	9,253	5,950
In-place leases
Finite-Lived Intangible Assets [Line Items]
Cost	222,394	163,728
Accumulated Amortization	(55,605)	(26,702)
Net	166,789	137,026
Above market leases
Finite-Lived Intangible Assets [Line Items]
Cost	35,478	26,787
Accumulated Amortization	(6,909)	(3,174)
Net	28,569	23,613
Leasehold interest
Finite-Lived Intangible Assets [Line Items]
Cost	712	712
Accumulated Amortization	(124)	(64)
Net	588	648
Below Market Ground Lease
Finite-Lived Intangible Assets [Line Items]
Cost	42,878	13,941
Accumulated Amortization	(539)	(68)
Net	42,339	13,873
Below market in-place lease
Liability
Below market lease, cost	10,297	6,068
Below market lease, accumulated amortization	(2,345)	(799)
Below Market Lease, Net	7,952	5,269
Below market in-place ground lease
Liability
Cost	1,345	701
Accumulated Amortization	(44)	(20)
Net	$ 1,301	$ 681