Deferred Revenue, Intangibles, Net and Other Liabilities (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 87,338		$ 96,564
Amortization of below market lease intangibles	6,100	$ 4,000
Unamortized below market lease liabilities
Deferred Revenue Arrangement [Line Items]
Deferred revenue	73,653		83,117
Retainage payables and other
Deferred Revenue Arrangement [Line Items]
Deferred revenue	4,051		3,954
Tenant rent payments received in advance
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 9,634		$ 9,493