Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
ASSETS
Tenant and other receivables, allowance for doubtful accounts	$ 3,891	$ 5,526
Receivable arising from the straight-lining of rents, allowance	1,798	954
Deferred leasing costs, accumulated amortization	198,100	191,827
Identified intangible assets, accumulated amortization	$ 163,406	$ 150,837
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS / PARTNERSHIP UNITS AND EQUITY
Preferred shares of beneficial interest: par value per share (in dollars per share)	$ 0	$ 0
Preferred shares of beneficial interest: authorized shares	110,000,000	110,000,000
Preferred shares of beneficial interest: issued shares	36,799,573	36,799,573
Preferred shares of beneficial interest: outstanding shares	36,799,573	36,799,573
Common shares of beneficial interest: par value per share (in dollars per share)	$ 0.04	$ 0.04
Common shares of beneficial interest: authorized shares	250,000,000	250,000,000
Common shares of beneficial interest: issued shares	190,237,957	189,983,858
Common shares of beneficial interest: outstanding shares	190,237,957	189,983,858
Class A Unit
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS / PARTNERSHIP UNITS AND EQUITY
Outstanding Partnership Units held by Third Parties	12,616,515	12,528,899
Cumulative Redeemable Preferred Unit
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS / PARTNERSHIP UNITS AND EQUITY
Outstanding Partnership Units held by Third Parties	177,101	177,101
Vornado Realty L.P.
ASSETS
Tenant and other receivables, allowance for doubtful accounts	$ 3,891	$ 5,526
Receivable arising from the straight-lining of rents, allowance	1,798	954
Deferred leasing costs, accumulated amortization	198,100	191,827
Identified intangible assets, accumulated amortization	$ 163,406	$ 150,837
Vornado Realty L.P. | Class A Unit
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS / PARTNERSHIP UNITS AND EQUITY
Outstanding Partnership Units held by Third Parties	12,616,515	12,528,899
Vornado Realty L.P. | Cumulative Redeemable Preferred Unit
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS / PARTNERSHIP UNITS AND EQUITY
Outstanding Partnership Units held by Third Parties	177,101	177,101