Real Estate - Restricted Cash (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($) property
Schedule of restricted cash
Restricted cash beginning balance	$ 24,748
Restricted cash ending balance	$ 15,311
Midland Mortgage Loan Restricted Lockbox
Schedule of restricted cash
Number of rented properties serve as collateral | property	8
Real Estate Asset Acquisitions and Contributions
Schedule of restricted cash
Restricted cash beginning balance	$ 24,748
Additions	4,002
Deductions	(13,439)
Restricted cash ending balance	15,311
Real Estate Asset Acquisitions and Contributions | Tenant Improvement Reserves
Schedule of restricted cash
Restricted cash beginning balance	13,406
Additions	308
Deductions	(2,553)
Restricted cash ending balance	11,161
Real Estate Asset Acquisitions and Contributions | Midland Mortgage Loan Reserves
Schedule of restricted cash
Restricted cash beginning balance	453
Additions	0
Deductions	(385)
Restricted cash ending balance	68
Real Estate Asset Acquisitions and Contributions | Real Estate Tax Reserves (Emporia Partners and TW Telecom)
Schedule of restricted cash
Restricted cash beginning balance	1,891
Additions	1,725
Deductions	(1,695)
Restricted cash ending balance	1,921
Real Estate Asset Acquisitions and Contributions | Property Insurance Reserves (Emporia Partners)
Schedule of restricted cash
Restricted cash beginning balance	301
Additions	0
Deductions	(172)
Restricted cash ending balance	129
Real Estate Asset Acquisitions and Contributions | Restricted deposits/Leasing commission reserve
Schedule of restricted cash
Restricted cash beginning balance	68
Additions	25
Deductions	(5)
Restricted cash ending balance	88
Real Estate Asset Acquisitions and Contributions | Midland Mortgage Loan Restricted Lockbox
Schedule of restricted cash
Restricted cash beginning balance	2,044
Additions	1,569
Deductions	(2,044)
Restricted cash ending balance	1,569
Real Estate Asset Acquisitions and Contributions | Restricted Rent Receipts
Schedule of restricted cash
Restricted cash beginning balance	6,585
Additions	375
Deductions	(6,585)
Restricted cash ending balance	$ 375