Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
OPERATING ACTIVITIES
Net income	$ 68,388	$ 104,213
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	117,160	116,547
Amortization of deferred financing costs	2,168	2,629
Impairment - real estate assets	16,775	0
Equity in earnings of unconsolidated joint ventures	(1,652)	(5,705)
Distributions from unconsolidated joint ventures	4,441	0
Gain on property dispositions	(3,520)	(48,152)
Share-based compensation/Non-cash compensation	9,504	8,500
Other	(6,750)	(2,210)
Changes in operating assets and liabilities:
Restricted cash	2,541	33,239
Accounts receivable	665	(1,307)
Deferred rent receivable	(11,319)	(7,548)
Prepaid expenses and other assets	(16,540)	(29,907)
Accounts payable	(5,647)	9,100
Accrued interest	2,663	2,753
Other liabilities	(5,780)	(34,802)
Net cash provided by operating activities	173,097	147,350
INVESTING ACTIVITIES
Investment in operating properties - acquisitions	(36,714)	(90,837)
Investment in operating properties - other	(33,585)	(39,073)
Investments in and advances to unconsolidated joint ventures	(17,182)	(12,008)
Distributions from unconsolidated joint ventures	7,979	5,429
Net proceeds from disposition of properties/land	156,891	351,299
Investment in development in progress	(78,120)	(150,199)
Investment in land held for development	(23,150)	(12,793)
Investment in deferred leasing costs	(23,395)	(18,252)
Other	5,154	5,627
Net cash (used in) provided by investing activities	(42,122)	39,193
FINANCING ACTIVITIES
Net proceeds from issuance of common shares	25,227	31,588
Proceeds from unsecured notes	398,576	0
Repayment of unsecured notes	(300,000)	0
Repayments of mortgage loans	(4,567)	(7,013)
Proceeds from credit facility	613,200	0
Repayments on credit facility	(710,200)	0
Payment of deferred financing costs	(3,551)	(3,635)
Distribution paid on common shares	(141,395)	(139,598)
Distribution paid on units	(3,821)	(3,814)
Net cash used in financing activities	(126,531)	(122,472)
Net increase in cash and cash equivalents	4,444	64,071
(Decrease) increase in cash and cash equivalents related to foreign currency translation	(737)	1,193
Cash and cash equivalents at beginning of period	69,346	163,414
Cash and cash equivalents at end of period	73,053	228,678
Liberty Property Limited Partnership [Member]
OPERATING ACTIVITIES
Net income	68,388	104,213
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	117,160	116,547
Amortization of deferred financing costs	2,168	2,629
Impairment - real estate assets	16,775	0
Equity in earnings of unconsolidated joint ventures	(1,652)	(5,705)
Distributions from unconsolidated joint ventures	4,441	0
Gain on property dispositions	(3,520)	(48,152)
Share-based compensation/Non-cash compensation	9,504	8,500
Other	(6,750)	(2,210)
Changes in operating assets and liabilities:
Restricted cash	2,541	33,239
Accounts receivable	665	(1,307)
Deferred rent receivable	(11,319)	(7,548)
Prepaid expenses and other assets	(16,540)	(29,907)
Accounts payable	(5,647)	9,100
Accrued interest	2,663	2,753
Other liabilities	(5,780)	(34,802)
Net cash provided by operating activities	173,097	147,350
INVESTING ACTIVITIES
Investment in operating properties - acquisitions	(36,714)	(90,837)
Investment in operating properties - other	(33,585)	(39,073)
Investments in and advances to unconsolidated joint ventures	(17,182)	(12,008)
Distributions from unconsolidated joint ventures	7,979	5,429
Net proceeds from disposition of properties/land	156,891	351,299
Investment in development in progress	(78,120)	(150,199)
Investment in land held for development	(23,150)	(12,793)
Investment in deferred leasing costs	(23,395)	(18,252)
Other	5,154	5,627
Net cash (used in) provided by investing activities	(42,122)	39,193
FINANCING ACTIVITIES
Proceeds from unsecured notes	398,576	0
Repayment of unsecured notes	(300,000)	0
Repayments of mortgage loans	(4,567)	(7,013)
Proceeds from credit facility	613,200	0
Repayments on credit facility	(710,200)	0
Payment of deferred financing costs	(3,551)	(3,635)
Capital contributions	25,227	31,588
Distributions to partners	(145,216)	(143,412)
Net cash used in financing activities	(126,531)	(122,472)
Net increase in cash and cash equivalents	4,444	64,071
(Decrease) increase in cash and cash equivalents related to foreign currency translation	(737)	1,193
Cash and cash equivalents at beginning of period	69,346	163,414
Cash and cash equivalents at end of period	$ 73,053	$ 228,678