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	$ 68,388									$ 68,388
Other comprehensive loss - foreign currency translation	1,741									1,741
Other comprehensive loss - derivative instruments	(319)									(319)
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			4,341			4,341			4,341
Net income	110,120				107,181	107,181	2,590	113	109,884	110,120	107,181	2,590	113	109,884
Contributions from partners											16,702			16,702
Distributions					(139,188)	(139,188)	(3,498)	(113)	(142,799)
Distributions to partners											(139,188)	(3,498)	(113)	(142,799)
Share/Unit repurchase		(1)	(40,895)			(40,896)			(40,896)		(40,896)			(40,896)
Share-based compensation			12,361			12,361			12,361
Other comprehensive loss - foreign currency translation	(18,596)			(18,157)		(18,157)	(439)		(18,596)	(18,596)	(18,157)	(439)		(18,596)
Other comprehensive loss - derivative instruments	(1,795)			(1,753)		(1,753)	(42)		(1,795)	(1,795)	(1,753)	(42)		(1,795)
Ending Balance at Jun. 30, 2016	2,932,447	$ 147	$ 3,645,434	$ (37,803)	$ (730,961)	$ 2,876,817	$ 51,711	$ 3,919	$ 2,932,447	2,932,447	$ 2,876,817	$ 51,711	$ 3,919	$ 2,932,447
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)	236									236
Distributions (Mezzanine)	(236)									(236)
Noncontrolling Interest - Operating Partnership (Mezzanine) - Ending Balance at Jun. 30, 2016	$ 7,537									$ 7,537