Related Person Transactions - Two North Riverside Plaza Joint Venture Limited Partnership and Equity Group Investments and Associated Entities (Details) $ in Thousands				12 Months Ended
	Dec. 29, 2015 parking_space	Jul. 20, 2015 option	Jan. 30, 2015 option	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Two North Riverside Plaza Joint Venture Limited Partnership
Related Party Transaction [Line Items]
Lease term		5 years
Number of renewal options | option		1
Renewal option term		5 years
Tenant improvements				$ 700
Operating lease, termination period duration				30 days
Expenses from transactions with related party				$ 800	$ 800
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity
2018				900
2019				900
2020				900
Due to related party				$ 0	$ 100
Equity Group
Related Party Transaction [Line Items]
Lease term			1 year
Number of renewal options | option			1
Renewal option term			3 months
Expenses from transactions with related party						$ 13
Equity Group | Terminated Agreement
Related Party Transaction [Line Items]
Expenses from transactions with related party						200
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity
Number of parking spaces | parking_space	1
Equity Residential Management, L.L.C.
Related Party Transaction [Line Items]
Expenses from transactions with related party						$ 400