Consolidated Statements of Equity - USD ($) $ in Thousands	Total	COMMON SHARES OF BENEFICIAL INTEREST	ADDITIONAL PAID-IN CAPITAL	ACCUMULATED OTHER COMPREHENSIVE LOSS	DISTRIBUTIONS IN EXCESS OF NET INCOME	TOTAL LIBERTY PROPERTY TRUST SHAREHOLDERS’ EQUITY	NONCONTROLLING INTEREST - OPERATING PARTNERSHIP	NONCONTROLLING INTEREST - CONSOLIDATED JOINT VENTURES	Common shares	Liberty Property Limited Partnership	Liberty Property Limited Partnership GENERAL PARTNER	Liberty Property Limited Partnership LIMITED PARTNER	Liberty Property Limited Partnership NONCONTROLLING INTEREST - CONSOLIDATED JOINT VENTURES	Liberty Property Limited Partnership TOTAL OWNERS’ EQUITY	Liberty Property Limited Partnership Common Units GENERAL PARTNER	Liberty Property Limited Partnership Common Units LIMITED PARTNER	Liberty Property Limited Partnership, Preferred Activity
Common shares outstanding - Beginning Balance (shares) at Dec. 31, 2017									147,450,691
General Partner's units outstanding - Beginning Balance (units) at Dec. 31, 2017															147,450,691
Limited Partners' units outstanding - Beginning Balance (units) at Dec. 31, 2017																3,520,205
Beginning balance at Dec. 31, 2017	$ 3,148,366	$ 147	$ 3,674,978	$ (37,797)	$ (549,970)	$ 3,087,358	$ 56,159	$ 4,849			$ 3,087,358	$ 56,159	$ 4,849	$ 3,148,366
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net proceeds from the issuance of common shares	3,267	1	3,266			3,267
Net proceeds from issuance of common shares (shares)									322,450
Net income	143,607				140,181	140,181	3,339	87			140,181	3,339	87	143,607
Contributions from partners											8,683			8,683
Contributions from partners (units)															322,450
Distributions to partners											(59,094)	(1,506)	(85)	(60,685)
Distributions	(60,685)				(59,094)	(59,094)	(1,506)	(85)
Share-based compensation	5,416		5,416			5,416
Other comprehensive loss - foreign currency translation activity	7,932			7,747		7,747	185			$ 7,932	7,747	185		7,932
Other comprehensive income - derivative instruments activity	385			376		376	9			$ 385	376	9		385
Common shares outstanding - Ending Balance (shares) at Mar. 31, 2018									147,773,141
General Partner's units outstanding - Ending Balance (units) at Mar. 31, 2018															147,773,141
Limited Partners' units outstanding - Ending Balance (units) at Mar. 31, 2018																3,520,205
Ending balance at Mar. 31, 2018	3,248,288	148	3,683,660	(29,674)	(468,883)	3,185,251	58,186	4,851			3,185,251	58,186	4,851	3,248,288
Noncontrolling Interest - Operating Partnership (Mezzanine) - Beginning Balance at Dec. 31, 2017	7,537																$ 7,537
Increase (Decrease) in Temporary Equity [Roll Forward]
Net income (Mezzanine)	118																118
Distributions	(118)																(118)
Noncontrolling Interest - Operating Partnership (Mezzanine) - Ending Balance at Mar. 31, 2018	$ 7,537																7,537
Common shares outstanding - Beginning Balance (shares) at Dec. 31, 2018	147,899,354								147,899,354	147,899,354
General Partner's units outstanding - Beginning Balance (units) at Dec. 31, 2018															147,899,354
Limited Partners' units outstanding - Beginning Balance (units) at Dec. 31, 2018	3,520,205.00									3,520,205						3,520,205
Beginning balance at Dec. 31, 2018	$ 3,396,772	148	3,691,778	(55,243)	(306,822)	3,329,861	61,471	5,440		$ 3,396,772	3,329,861	61,471	5,440	3,396,772
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net proceeds from the issuance of common shares	3,909	0	3,909			3,909
Net proceeds from issuance of common shares (shares)									358,688
Net income	55,664				54,330	54,330	1,290	44			54,330	1,290	44	55,664
Contributions from partners											6,005			6,005
Contributions from partners (units)															358,688
Distributions to partners											(60,787)	(1,563)	(800)	(63,150)
Distributions	(63,150)				(60,787)	(60,787)	(1,563)	(800)
Share-based compensation	2,096		2,096			2,096
Other comprehensive loss - foreign currency translation activity	5,376			5,251		5,251	125			5,376	5,251	125		5,376
Other comprehensive income - derivative instruments activity	(1,854)			(1,811)		(1,811)	(43)			$ (1,854)	(1,811)	(43)		(1,854)
Redemption of noncontrolling interest - preferred units	$ (2,200)										0			0			(2,200)
Common shares outstanding - Ending Balance (shares) at Mar. 31, 2019	148,258,042								148,258,042	148,258,042
General Partner's units outstanding - Ending Balance (units) at Mar. 31, 2019															148,258,042
Limited Partners' units outstanding - Ending Balance (units) at Mar. 31, 2019	3,520,205									3,520,205						3,520,205
Ending balance at Mar. 31, 2019	$ 3,398,813	$ 148	$ 3,697,783	$ (51,803)	$ (313,279)	$ 3,332,849	$ 61,280	$ 4,684		$ 3,398,813	$ 3,332,849	$ 61,280	$ 4,684	$ 3,398,813
Noncontrolling Interest - Operating Partnership (Mezzanine) - Beginning Balance at Dec. 31, 2018	7,537									7,537							7,537
Increase (Decrease) in Temporary Equity [Roll Forward]
Net income (Mezzanine)	84																84
Distributions	(84)																(84)
Noncontrolling Interest - Operating Partnership (Mezzanine) - Ending Balance at Mar. 31, 2019	$ 5,337									$ 5,337							$ 5,337