Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Aug. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	$ 1,200
Other intangible assets		$ 7,761
Below market ground leases		$ 118,050
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	3,724
Finite-Lived Intangible Assets, Amortization Expense, Year Two	3,724
Finite-Lived Intangible Assets, Amortization Expense, Year Three	3,724
Finite-Lived Intangible Assets, Amortization Expense, Year Four	3,724
Finite-Lived Intangible Assets, Amortization Expense, Year Five	$ 3,724
Finite-Lived Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Remaining Amortization Period	53 years
Finite-Lived Intangible Assets, Gross	$ 119,411
Finite-Lived Intangible Assets, Accumulated Amortization	(1,241)
Finite-Lived Intangible Assets, Net	118,170
Below market ground leases
Finite-Lived Intangible Assets [Line Items]
Below Market Lease, Net	$ 116,873
Finite-Lived Intangible Assets, Remaining Amortization Period	53 years
Below Market Lease, Accumulated Amortization	$ (1,176)
Below market ground leases	$ 118,050
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Remaining Amortization Period	7 years
Other intangible assets	$ 1,361
Finite-Lived Intangible Assets, Accumulated Amortization	(65)
Other Intangible Assets, Net	$ 1,297