Commitments and Contingencies (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) category	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Loss Contingencies [Line Items]
Number of tenant and building improvement categories | category	2
Operating Leases, Future Minimum Payments Due [Abstract]
2017	$ 93
2018	93
2019	93
2020	93
2021	93
Thereafter	2,439
Total	2,904
Land [Member]
Operating Leases, Future Minimum Payments Due [Abstract]
Ground rent expense	100	$ 200	$ 500
Building [Member]
Operating Leases, Future Minimum Payments Due [Abstract]
Net book value of real estate assets subject to operating ground leases	4,700	5,000
Collectibility of Tenant Reimbursements [Member]
Loss Contingencies [Line Items]
Additional expense related to such tenant audits/disputes	$ 1,100	$ 400	$ 600
NonIncremental Capital Expenditures [Member]
Loss Contingencies [Line Items]
Period for commitments for funding non-incremental capital expenditures	3 years
Non-incremental capital expenditures for tenant improvements	$ 35,300
NonIncremental Capital Expenditures [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Period for commitments for funding non-incremental capital expenditures	5 years
Incremental Capital Expenditures [Member]
Loss Contingencies [Line Items]
Non-incremental capital expenditures for tenant improvements	$ 29,800