Consolidated Balance Sheets (Parentheticals) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Deferred financing and leasing costs, accumulated amortization	$ 161,544,000	$ 152,309,000
Limited Partners' common units outstanding	3,528,281	3,530,031
Common shares of beneficial interest, par value per share	$ 0.001	$ 0.001
Common shares of beneficial interest, shares authorized	283,987,000	283,987,000
Common shares of beneficial interest, shares issued	147,304,661	146,993,018
Common shares of beneficial interest, shares outstanding	147,304,661	146,993,018
Liberty Property Limited Partnership [Member]
Deferred financing and leasing costs, accumulated amortization	$ 161,544,000	$ 152,309,000
Limited Partners' common units outstanding	3,528,281	3,530,031
Common shares of beneficial interest, shares outstanding	147,304,661	146,993,018
Series I 2 [Member]
Noncontrolling interest - operating partnership, preferred units outstanding	301,483	301,483
Series I 2 [Member] | Liberty Property Limited Partnership [Member]
Noncontrolling interest - operating partnership, preferred units outstanding	301,483	301,483