Consolidated Statements of Cash Flows - USD ($)	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
OPERATING ACTIVITIES
Net income	$ 110,120,000	$ 68,388,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	109,047,000	117,160,000
Amortization of deferred financing costs	2,004,000	2,168,000
Impairment - real estate assets	0	16,775,000
Equity in earnings of unconsolidated joint ventures	(10,497,000)	(1,652,000)
Distributions from unconsolidated joint ventures	0	4,441,000
Gain on property dispositions	(24,353,000)	(3,520,000)
Share-based compensation/Non-cash compensation	11,553,000	9,504,000
Other	(4,424,000)	(6,750,000)
Changes in operating assets and liabilities:
Restricted cash	3,390,000	2,541,000
Accounts receivable	1,794,000	665,000
Deferred rent receivable	(8,897,000)	(11,319,000)
Prepaid expenses and other assets	312,000	(16,540,000)
Accounts payable	3,877,000	(5,647,000)
Accrued interest	342,000	2,663,000
Other liabilities	(17,342,000)	(5,780,000)
Net cash provided by operating activities	176,926,000	173,097,000
INVESTING ACTIVITIES
Investment in properties - acquisitions	(8,000,000)	(36,714,000)
Investment in properties - other	(30,338,000)	(33,585,000)
Investments in and advances to unconsolidated joint ventures	(31,372,000)	(17,182,000)
Distributions from unconsolidated joint ventures	35,250,000	7,979,000
Net proceeds from disposition of properties/land	139,814,000	156,891,000
Investment in development in progress	(175,744,000)	(78,120,000)
Investment in land held for development	(36,855,000)	(23,150,000)
Payment of deferred leasing costs	(15,057,000)	(23,395,000)
Investing - Other	7,842,000	5,154,000
Net cash used in investing activities	(114,460,000)	(42,122,000)
FINANCING ACTIVITIES
Net proceeds from issuance of common shares	4,341,000	25,227,000
Share repurchase	40,896,000	0
Proceeds from unsecured notes	0	398,576,000
Repayment of unsecured notes	0	(300,000,000)
Repayments of mortgage loans	(22,123,000)	(4,567,000)
Proceeds from credit facility	338,300,000	613,200,000
Repayments on credit facility	(202,300,000)	(710,200,000)
Payment of deferred financing costs	0	(3,551,000)
Distribution paid on common shares	(139,742,000)	(141,395,000)
Distribution paid on units	(3,847,000)	(3,821,000)
Net cash used in financing activities	(66,267,000)	(126,531,000)
Net (decrease) increase in cash and cash equivalents	(3,801,000)	4,444,000
Decrease in cash and cash equivalents related to foreign currency translation	(2,212,000)	(737,000)
Cash and cash equivalents at beginning of period	35,353,000	69,346,000
Cash and cash equivalents at end of period	29,340,000	73,053,000
Liberty Property Limited Partnership [Member]
OPERATING ACTIVITIES
Net income	110,120,000	68,388,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	109,047,000	117,160,000
Amortization of deferred financing costs	2,004,000	2,168,000
Impairment - real estate assets	0	16,775,000
Equity in earnings of unconsolidated joint ventures	(10,497,000)	(1,652,000)
Distributions from unconsolidated joint ventures	0	4,441,000
Gain on property dispositions	(24,353,000)	(3,520,000)
Share-based compensation/Non-cash compensation	11,553,000	9,504,000
Other	(4,424,000)	(6,750,000)
Changes in operating assets and liabilities:
Restricted cash	3,390,000	2,541,000
Accounts receivable	1,794,000	665,000
Deferred rent receivable	(8,897,000)	(11,319,000)
Prepaid expenses and other assets	312,000	(16,540,000)
Accounts payable	3,877,000	(5,647,000)
Accrued interest	342,000	2,663,000
Other liabilities	(17,342,000)	(5,780,000)
Net cash provided by operating activities	176,926,000	173,097,000
INVESTING ACTIVITIES
Investment in properties - acquisitions	(8,000,000)	(36,714,000)
Investment in properties - other	(30,338,000)	(33,585,000)
Investments in and advances to unconsolidated joint ventures	(31,372,000)	(17,182,000)
Distributions from unconsolidated joint ventures	35,250,000	7,979,000
Net proceeds from disposition of properties/land	139,814,000	156,891,000
Investment in development in progress	(175,744,000)	(78,120,000)
Investment in land held for development	(36,855,000)	(23,150,000)
Payment of deferred leasing costs	(15,057,000)	(23,395,000)
Investing - Other	7,842,000	5,154,000
Net cash used in investing activities	(114,460,000)	(42,122,000)
FINANCING ACTIVITIES
Proceeds from unsecured notes	0	398,576,000
Repayment of unsecured notes	0	(300,000,000)
Repayments of mortgage loans	(22,123,000)	(4,567,000)
Proceeds from credit facility	338,300,000	613,200,000
Repayments on credit facility	(202,300,000)	(710,200,000)
Payment of deferred financing costs	0	(3,551,000)
Capital contributions	4,341,000	25,227,000
Distributions to partners	(184,485,000)	(145,216,000)
Net cash used in financing activities	(66,267,000)	(126,531,000)
Net (decrease) increase in cash and cash equivalents	(3,801,000)	4,444,000
Decrease in cash and cash equivalents related to foreign currency translation	(2,212,000)	(737,000)
Cash and cash equivalents at beginning of period	35,353,000	69,346,000
Cash and cash equivalents at end of period	$ 29,340,000	$ 73,053,000