Deferred Revenue and Acquisition Related Liabilities, net (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred Revenue Arrangement [Line Items]
Acquisition-related intangible liabilities, net	$ 41,578	$ 32,324
Deferred revenue and acquisition-related intangible liabilities, net	150,360	128,156
Tenant funded tenant improvements [Member]
Deferred Revenue Arrangement [Line Items]
Deferred revenue	99,489	90,825
Other deferred revenue [Member]
Deferred Revenue Arrangement [Line Items]
Deferred revenue	$ 9,293	$ 5,007