Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Gain on property dispositions in discontinued operations	$ 94,878	$ 0	$ 184,689	$ 0
Liberty Property Limited Partnership [Member]
Gain on property dispositions in discontinued operations	$ 94,878	$ 0	$ 184,689	$ 0

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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