Consolidated Statement of Equity - USD ($)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Accumulated Distributions in Excess of Net Income [Member]	Parent [Member]	Noncontrolling interest operating partnership Common [Member]	Noncontrolling interest-consolidated joint ventures [Member]	Liberty Property Limited Partnership [Member]	Liberty Property Limited Partnership [Member] General Partner [Member]	Liberty Property Limited Partnership [Member] Limited Partner [Member]	Liberty Property Limited Partnership [Member] Noncontrolling interest-consolidated joint ventures [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income - foreign currency translation	$ (5,087,000)								$ (5,087,000)
Other comprehensive income - derivative instruments	(1,360,000)								(1,360,000)
Beginning Balance at Dec. 31, 2016	3,062,923,000	$ 147,000	$ 3,655,910,000	$ (56,031,000)	$ (596,635,000)	$ 3,003,391,000	$ 54,631,000	$ 4,901,000	3,062,923,000	$ 3,003,391,000	$ 54,631,000	$ 4,901,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net proceeds from the issuance of common shares	852,000	0	852,000	0	0	852,000	0
Net income	44,126,000	0	0	0	43,032,000	43,032,000	1,031,000	63,000	44,126,000	43,032,000	1,031,000	63,000
Contributions from partners									4,803,000	4,803,000
Distributions	(60,426,000)	0	0	0	(58,821,000)	(58,821,000)	(1,542,000)	(63,000)
Distributions to partners									(60,426,000)	(58,821,000)	(1,542,000)	(63,000)
Share-based compensation	3,951,000	0	3,951,000	0	0	3,951,000
Other comprehensive income - foreign currency translation	3,177,000	0	0	3,103,000	0	3,103,000	74,000		3,177,000	3,103,000	74,000
Other comprehensive income - derivative instruments	313,000	0	0	306,000	0	306,000	7,000		313,000	306,000	7,000
Redemption of noncontrolling interests - common units	0	0	27,000	0	0	27,000	(27,000)		0	27,000	(27,000)
Ending Balance at Mar. 31, 2017	3,054,916,000	$ 147,000	$ 3,660,740,000	$ (52,622,000)	$ (612,424,000)	$ 2,995,841,000	$ 54,174,000	$ 4,901,000	3,054,916,000	$ 2,995,841,000	$ 54,174,000	$ 4,901,000
Noncontrolling Interest - Operating Partnership (Mezzanine) - Beginning Balance at Dec. 31, 2016	7,537,000								7,537,000
Increase (Decrease) in Temporary Equity [Roll Forward]
Net income (Mezzanine)	118,000								118,000
Distributions (Mezzanine)	(118,000)								(118,000)
Noncontrolling Interest - Operating Partnership (Mezzanine) - Ending Balance at Mar. 31, 2017	$ 7,537,000								$ 7,537,000