Income per Common Unit of the Operating Partnership (Units and Distributions) (Details) - Liberty Property Limited Partnership [Member] - Common units [Member] - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Distributions per common unit	$ 1.90	$ 1.90	$ 1.90
Limited Partner [Member]
Class of Stock [Line Items]
Number of common units converted	9,044	14,491	3,000