Consolidated Statement of Equity - USD ($) $ in Thousands	Total	Common Shares Of Beneficial Interest [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income [Member]	Distributions in Excess of Net Income [Member]	Total Liberty Property Trust Shareholders' Equity [Member]	Noncontrolling interest operating partnership Common [Member]	Noncontrolling interest-consolidated joint ventures [Member]	Total Equity [Member]	Liberty Property Limited Partnership [Member]	Liberty Property Limited Partnership [Member] General Partners Equity [Member]	Liberty Property Limited Partnership [Member] Limited Partners' Equity - Common Units [Member]	Liberty Property Limited Partnership [Member] Noncontrolling interest-consolidated joint ventures [Member]	Liberty Property Limited Partnership [Member] Total Equity [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 31,862									$ 31,862
Other comprehensive loss - foreign currency translation	(10,410)									(10,410)
Other comprehensive loss - derivative instruments	(947)									(947)
Beginning Balance at Dec. 31, 2015	3,009,947	$ 148	$ 3,669,627	$ (17,893)	$ (698,954)	$ 2,952,928	$ 53,100	$ 3,919	$ 3,009,947	3,009,947	$ 2,952,928	$ 53,100	$ 3,919	$ 3,009,947
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net proceeds from the issuance of common shares			504			504			504
Net income	59,063				57,554	57,554	1,391	0	58,945	59,063	57,554	1,391	0	58,945
Contributions from partners											11,609			11,609
Distributions					(69,634)	(69,634)	(1,676)	0	(71,310)
Distributions to partners											(69,634)	(1,676)		(71,310)
Share/Unit repurchase		(1)	(40,895)			(40,896)			(40,896)		(40,896)			(40,896)
Share-based compensation			11,105			11,105			11,105
Other comprehensive loss - foreign currency translation	(5,087)			(4,967)		(4,967)	(120)		(5,087)	(5,087)	(4,967)	(120)		(5,087)
Other comprehensive loss - derivative instruments	(1,360)			(1,328)		(1,328)	(32)		(1,360)	(1,360)	(1,328)	(32)		(1,360)
Ending Balance at Mar. 31, 2016	2,961,848	$ 147	$ 3,640,341	$ (24,188)	$ (711,034)	$ 2,905,266	$ 52,663	$ 3,919	$ 2,961,848	2,961,848	$ 2,905,266	$ 52,663	$ 3,919	$ 2,961,848
Noncontrolling Interest - Operating Partnership (Mezzanine) - Beginning Balance at Dec. 31, 2015	7,537									7,537
Increase (Decrease) in Temporary Equity [Roll Forward]
Net income (Mezzanine)	118									118
Distributions (Mezzanine)	(118)									(118)
Noncontrolling Interest - Operating Partnership (Mezzanine) - Ending Balance at Mar. 31, 2016	$ 7,537									$ 7,537