Rent Expense - Schedule of Minimum Lease Obligations (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) properties	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Leases [Abstract]
Number of properties pursuant to ground leases | properties	58
Number of properties pursuant to parking lease | properties	3
Maximum lease terms	99 years
Future minimum lease obligations under non-cancelable ground leases
2017	$ 2,408
2018	2,456
2019	2,475
2020	2,478
2021	2,536
Thereafter	67,233
Total	79,586
Rent expenses for parking and ground leases	$ 1,900	$ 1,300	$ 900