Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Real Estate [Abstract]
Land and land improvements	$ 1,186,960	$ 1,183,411
Building and improvements	5,127,287	5,124,521
Less accumulated depreciation	(1,159,991)	(1,148,228)
Operating real estate	5,154,256	5,159,704
Development in progress	335,927	360,948
Land held for development	341,356	336,967
Net real estate	5,831,539	5,857,619
Cash and cash equivalents	43,663	35,353
Restricted cash	6,606	9,018
Accounts receivable	18,319	14,343
Deferred rent receivable	121,278	118,787
Deferred financing and leasing costs, net of accumulated amortization (March 31, 2016, $170,558; December 31, 2015, $175,243)	183,813	192,038
Investments in and advances to unconsolidated joint ventures	210,341	218,454
Assets held for sale	7,918	12,968
Prepaid expenses and other assets	94,821	99,049
Total assets	6,518,298	6,557,629
LIABILITIES
Mortgage loans	304,360	307,908
Unsecured notes	2,580,910	2,580,108
Credit facility	260,000	259,000
Accounts payable	60,328	51,382
Accrued interest	43,130	26,154
Dividend and distributions payable	71,317	71,787
Other liabilities	228,868	243,806
Total liabilities	3,548,913	3,540,145
Noncontrolling interest - operating partnership - 301,483 preferred units outstanding as of March 31, 2016 and December 31, 2015	7,537	7,537
EQUITY
Common shares of beneficial interest, $.001 par value, 283,987,000 shares authorized; 146,603,946 and 147,577,984 shares issued and outstanding as of March 31, 2016 and December 31, 2015, respectively	147	148
Additional paid-in capital	3,640,341	3,669,627
Accumulated other comprehensive loss	(24,188)	(17,893)
Distributions in excess of net income	(711,034)	(698,954)
Total Liberty Property Trust shareholders' equity	2,905,266	2,952,928
Noncontrolling interest - operating partnership
Noncontrolling interest - operating partnerships	52,663	53,100
Noncontrolling interest - consolidated joint ventures	3,919	3,919
Total owners' equity	2,961,848	3,009,947
Total liabilities, noncontrolling interest - operating partnership and equity	6,518,298	6,557,629
Liberty Property Limited Partnership [Member]
Real Estate [Abstract]
Land and land improvements	1,186,960	1,183,411
Building and improvements	5,127,287	5,124,521
Less accumulated depreciation	(1,159,991)	(1,148,228)
Operating real estate	5,154,256	5,159,704
Development in progress	335,927	360,948
Land held for development	341,356	336,967
Net real estate	5,831,539	5,857,619
Cash and cash equivalents	43,663	35,353
Restricted cash	6,606	9,018
Accounts receivable	18,319	14,343
Deferred rent receivable	121,278	118,787
Deferred financing and leasing costs, net of accumulated amortization (March 31, 2016, $170,558; December 31, 2015, $175,243)	183,813	192,038
Investments in and advances to unconsolidated joint ventures	210,341	218,454
Assets held for sale	7,918	12,968
Prepaid expenses and other assets	94,821	99,049
Total assets	6,518,298	6,557,629
LIABILITIES
Mortgage loans	304,360	307,908
Unsecured notes	2,580,910	2,580,108
Credit facility	260,000	259,000
Accounts payable	60,328	51,382
Accrued interest	43,130	26,154
Dividend and distributions payable	71,317	71,787
Other liabilities	228,868	243,806
Total liabilities	3,548,913	3,540,145
Noncontrolling interest - operating partnership - 301,483 preferred units outstanding as of March 31, 2016 and December 31, 2015	7,537	7,537
EQUITY
General partner’s equity - 146,603,946 and 147,577,984 common units outstanding as of March 31, 2016 and December 31, 2015, respectively	2,905,266	2,952,928
Limited partners' equity	52,663	53,100
Noncontrolling interest - operating partnership
Noncontrolling interest - consolidated joint ventures	3,919	3,919
Total owners' equity	2,961,848	3,009,947
Total liabilities, noncontrolling interest - operating partnership and equity	$ 6,518,298	$ 6,557,629