Summary of Significant Accounting Policies - Schedule of Disaggregation of Revenue Streams of Rental Income and Percentage of Rental Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Amount of rental income	$ 632,831	$ 603,920
Percentage of rental income	100.00%
Amount of rental income	$ 592,813
Leasing Revenue [Member}
Percentage of rental income	93.70%
Utility Recoveries [Member]
Amount of rental income	$ 15,375
Percentage of rental income	2.40%
Parking Revenue [Member]
Amount of rental income	$ 7,797
Percentage of rental income	1.20%
Other Revenue [Member]
Amount of rental income	$ 16,846
Percentage of rental income	2.70%