Consolidated Balance Sheets (Unaudited) (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
ASSETS
Tenant and other receivables, allowance for doubtful accounts		$ 4,154
Receivable arising from the straight-lining of rents, allowance		1,644
Deferred leasing costs, accumulated amortization	$ 180,953	207,529
Identified intangible assets, accumulated amortization	$ 97,749	$ 172,114
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 (shares)	110,000,000	110,000,000
Preferred shares of beneficial interest: issued shares (shares)	36,797,580	36,798,580
Preferred shares of beneficial interest: outstanding shares (shares)	36,797,580	36,798,580
Common shares of beneficial interest: par value per share (in dollars per share)	$ 0.04	$ 0.04
Common shares of beneficial interest: authorized shares (shares)	250,000,000	250,000,000
Common shares of beneficial interest: issued shares (shares)	190,761,498	190,535,499
Common shares of beneficial interest: outstanding shares (shares)	190,761,498	190,535,499
Class A Unit
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS / PARTNERSHIP UNITS AND EQUITY
Outstanding Partnership Units held by Third Parties (units)	12,789,891	12,544,477
Cumulative Redeemable Preferred Unit
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS / PARTNERSHIP UNITS AND EQUITY
Outstanding Partnership Units held by Third Parties (units)	141,401	177,101
Vornado Realty L.P.
ASSETS
Tenant and other receivables, allowance for doubtful accounts		$ 4,154
Receivable arising from the straight-lining of rents, allowance		1,644
Deferred leasing costs, accumulated amortization	$ 180,953	207,529
Identified intangible assets, accumulated amortization	$ 97,749	$ 172,114
Vornado Realty L.P. | Class A Unit
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS / PARTNERSHIP UNITS AND EQUITY
Outstanding Partnership Units held by Third Parties (units)	12,789,891	12,544,477
Vornado Realty L.P. | Cumulative Redeemable Preferred Unit
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS / PARTNERSHIP UNITS AND EQUITY
Outstanding Partnership Units held by Third Parties (units)	141,401	177,101