Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
OPERATING ACTIVITIES
Net income	$ 104,213	$ 117,899
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	116,547	90,956
Amortization of deferred financing costs	2,629	1,964
Equity in earnings of unconsolidated joint ventures	(5,705)	(3,323)
Distributions from unconsolidated joint ventures	0	470
Gain on property dispositions	(48,152)	(49,364)
Share-based compensation	8,500	6,359
Other	(2,210)	(4,461)
Changes in operating assets and liabilities:
Restricted cash	33,239	5,478
Accounts receivable	(1,307)	875
Deferred rent receivable	(7,548)	(4,197)
Prepaid expenses and other assets	(29,907)	1,477
Accounts payable	9,100	1,161
Accrued interest	2,753	(158)
Other liabilities	(34,802)	(18,727)
Net cash provided by operating activities	147,350	146,409
INVESTING ACTIVITIES
Investment in operating properties - acquisitions	(90,837)	(133,500)
Investment in operating properties - other	(39,073)	(24,104)
Investments in and advances to unconsolidated joint ventures	(12,008)	(8,153)
Distributions from unconsolidated joint ventures	5,429	4,975
Net proceeds from disposition of properties/land	351,299	124,453
Net proceeds from public reimbursement receivable/escrow	5,627	10,845
Investment in development in progress	(150,199)	(47,843)
Investment in land held for development	(12,793)	(13,586)
Investment in deferred leasing costs	(18,252)	(15,166)
Net cash provided by (used in) investing activities	39,193	(102,079)
FINANCING ACTIVITIES
Net proceeds from issuance of common shares	31,588	108,852
Redemption of preferred units	0	(64,500)
Proceeds from mortgage loans	0	6,738
Repayments of mortgage loans	(7,013)	(2,506)
Proceeds from credit facility	0	269,550
Repayments on credit facility	0	(216,550)
Increase in deferred financing costs	(3,635)	(8)
Distribution paid on common shares	(139,598)	(113,241)
Distribution paid on units	(3,814)	(5,827)
Net cash used in financing activities	(122,472)	(17,492)
Net increase in cash and cash equivalents	64,071	26,838
Increase (decrease) in cash and cash equivalents related to foreign currency translation	1,193	(3,515)
Cash and cash equivalents at beginning of period	163,414	38,356
Cash and cash equivalents at end of period	228,678	61,679
Liberty Property Limited Partnership [Member]
OPERATING ACTIVITIES
Net income	104,213	117,899
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	116,547	90,956
Amortization of deferred financing costs	2,629	1,964
Equity in earnings of unconsolidated joint ventures	(5,705)	(3,323)
Distributions from unconsolidated joint ventures	0	470
Gain on property dispositions	(48,152)	(49,364)
Share-based compensation	8,500	6,359
Other	(2,210)	(4,461)
Changes in operating assets and liabilities:
Restricted cash	33,239	5,478
Accounts receivable	(1,307)	875
Deferred rent receivable	(7,548)	(4,197)
Prepaid expenses and other assets	(29,907)	1,477
Accounts payable	9,100	1,161
Accrued interest	2,753	(158)
Other liabilities	(34,802)	(18,727)
Net cash provided by operating activities	147,350	146,409
INVESTING ACTIVITIES
Investment in operating properties - acquisitions	(90,837)	(133,500)
Investment in operating properties - other	(39,073)	(24,104)
Investments in and advances to unconsolidated joint ventures	(12,008)	(8,153)
Distributions from unconsolidated joint ventures	5,429	4,975
Net proceeds from disposition of properties/land	351,299	124,453
Net proceeds from public reimbursement receivable/escrow	5,627	10,845
Investment in development in progress	(150,199)	(47,843)
Investment in land held for development	(12,793)	(13,586)
Investment in deferred leasing costs	(18,252)	(15,166)
Net cash provided by (used in) investing activities	39,193	(102,079)
FINANCING ACTIVITIES
Redemption of preferred units	0	(64,500)
Proceeds from mortgage loans	0	6,738
Repayments of mortgage loans	(7,013)	(2,506)
Proceeds from credit facility	0	269,550
Repayments on credit facility	0	(216,550)
Increase in deferred financing costs	(3,635)	(8)
Capital contributions	31,588	108,852
Distributions to partners	(143,412)	(119,068)
Net cash used in financing activities	(122,472)	(17,492)
Net increase in cash and cash equivalents	64,071	26,838
Increase (decrease) in cash and cash equivalents related to foreign currency translation	1,193	(3,515)
Cash and cash equivalents at beginning of period	163,414	38,356
Cash and cash equivalents at end of period	$ 228,678	$ 61,679