Income Statement Parenthetical (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Gain on property dispositions	$ 0	$ 38	$ 0	$ 46,292
Liberty Property Limited Partnership [Member]
Gain on property dispositions	$ 0	$ 38	$ 0	$ 46,292

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

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