Income per Common Unit of the Operating Partnership - Unit Repurchase (Details) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016 USD ($) shares	Sep. 30, 2016 USD ($) $ / shares shares
Class of Stock [Line Items]
Amount paid for repurchase of units		$ 40,896
Common shares [Member] | 2015 Share Repurchase Program [Member]
Class of Stock [Line Items]
Authorized amount of shares available to be repurchased under a share repurchase plan	$ 250,000	$ 250,000
Number of units repurchased during period | shares	0	1,400,000
Amount paid for repurchase of units		$ 40,900
Stock Acquired, Average Cost Per Share | $ / shares		$ 29.28
Liberty Property Limited Partnership [Member]
Class of Stock [Line Items]
Amount paid for repurchase of units		$ 40,896
Liberty Property Limited Partnership [Member] | Common Units [Member] | 2015 Share Repurchase Program [Member]
Class of Stock [Line Items]
Authorized amount of shares available to be repurchased under a share repurchase plan	$ 250,000	$ 250,000
Number of units repurchased during period | shares	0	1,400,000
Amount paid for repurchase of units		$ 40,900
Liberty Property Limited Partnership [Member] | Common shares [Member] | 2015 Share Repurchase Program [Member]
Class of Stock [Line Items]
Stock Acquired, Average Cost Per Share | $ / shares		$ 29.28