Investments in Real Estate and Real Estate Under Construction (Tables)

12 Months Ended

Dec. 31, 2012

Investments in Real Estate and Real Estate Under Construction [Abstract]

Schedule of Net Real Estate [Table Text Block]

The Company's real estate, net, consists of the following at December 31, 2012 and 2011:

	2012			2011
Real estate, at cost:
Buildings and building improvements	$	2,969,050		$	2,638,626
Land, land estates and land improvements	581,199			522,039
Fixtures and equipment	7,705			7,525
Construction in progress	6,512			4,056
Real estate intangibles:
In-place lease values	401,503			327,589
Tenant relationships	179,655			152,390
Above-market leases	104,756			66,939
Investments in real estate under construction	65,122			34,529
	4,315,502			3,753,693
Accumulated depreciation and amortization(1)	(1,150,417		)	(1,006,717		)
Real estate, net	$	3,165,085		$	2,746,976

(1) Includes accumulated amortization of real estate intangible assets of $412,349 and $368,349 in 2012 and 2011, respectively. The estimated amortization of the above real estate intangible assets for the next five years is $58,797 in 2013, $42,539 in 2014, $32,799 in 2015, $26,457 in 2016 and $23,056 in 2017.

Schedule of Purchase Price Allocation [Table Text Block]

The following table summarizes the allocation of the fair value of amounts recognized for each major class of assets and liabilities:

Real estate assets	$	325,310
Lease related intangible assets	124,330
Cash	8,107
Other assets	36,179
Total acquired assets	493,926
Secured debt	252,517
Other liabilities, including below-market leases	23,686
Total assumed liabilities	276,203
Fair value of acquired net assets (represents 100% interest)	$	217,723

Business Acquisition, Pro Forma Information [Table Text Block]

The information presented below is not necessarily indicative of what the actual results of operations would have been had the transaction been completed on January 1, 2011, nor does it purport to represent the Company's future operations:

	2012			2011
Gross revenues	$	372,603		$	356,918
Net income (loss) attributable to Lexington Realty Trust shareholders	$	8		$	(111,787	)
Net loss attributable to common shareholders	$	(22,985	)	$	(135,924	)
Net loss per common share - basic and diluted	$	(0.14	)	$	(0.89	)

Schedule of Acquired Properties [Table Text Block]

The Company, through property owner subsidiaries, completed the following acquisitions and build-to-suit transactions during 2012 and 2011:

2012:

										Real Estate Intangibles
Property Type	Location	Acquisition/Completion Date	Initial Cost Basis		Lease Expiration	Land and Land Estate		Building and Improvements		Lease in-place Value		Tenant Relationships Value
Office	Huntington, WV	January 2012	$	12,558	11/2026	$	1,368	$	9,527	$	1,405	$	258
Office	Florence, SC	February 2012	$	5,094	02/2024	$	774	$	3,629	$	505	$	186
Industrial	Missouri City, TX	April 2012	$	23,000	04/2032	$	14,555	$	5,895	$	2,135	$	415
Industrial	Shreveport, LA	June 2012	$	12,941	03/2022	$	1,078	$	10,134	$	1,590	$	139
Retail	Valdosta, GA(1)	August 2012	$	7,791	08/2027	$	2,128	$	5,663	$	—	$	—
Office	Jessup, PA	August 2012	$	24,917	08/2027	$	2,520	$	17,656	$	3,336	$	1,405
Office	Saint Joseph, MO	September 2012	$	17,571	06/2027	$	607	$	14,004	$	2,528	$	432
Retail	Opelika, AL(1)	November 2012	$	7,978	11/2027	$	1,446	$	6,532	$	—	$	—
Office	Phoenix, AZ	December 2012	$	53,200	12/2029	$	5,585	$	36,099	$	8,956	$	2,560
Office	Eugene, OR	December 2012	$	17,558	11/2027	$	1,541	$	13,099	$	2,414	$	504
			$	182,608		$	31,602	$	122,238	$	22,869	$	5,899
Weighted-average life of intangible assets (years)										15.7		16.0

(1) Incurred leasing costs of $488 for Valdosta and $355 for Opelika.

2011:

										Real Estate Intangibles
Property Type	Location	Acquisition/Consolidation Date	Initial Cost Basis		Lease Expiration	Land		Building and Improvements		Above Market Lease Value		Lease in-place Value		Tenant Relationships Value
Industrial	Byhalia, MS	May 2011	$	27,492	03/2026	$	1,005	$	21,483	$	—	$	4,097	$	907
Office	Rock Hill, SC	May 2011	$	7,395	08/2021	$	551	$	4,313	$	—	$	1,853	$	678
Office (1)	Allen, TX	May 2011	$	36,304	03/2018	$	5,591	$	21,607	$	—	$	5,127	$	3,979
Industrial	Shelby, NC	June 2011	$	23,470	05/2031	$	1,421	$	18,917	$	—	$	2,712	$	420
Office	Columbus, OH	July 2011	$	6,137	07/2027	$	433	$	2,773	$	—	$	2,205	$	726
Industrial	Chillicothe, OH	October 2011	$	12,110	06/2026	$	736	$	9,021	$	—	$	1,859	$	494
Office (2)	Aurora, IL	October 2011	$	15,300	09/2017	$	3,063	$	5,943	$	1,272	$	3,616	$	1,406
			$	128,208		$	12,800	$	84,057	$	1,272	$	21,469	$	8,610
Weighted-average life of intangible assets (years)										6.0		11.8		9.7

(1)    The Company acquired the property from Net Lease Strategic Assets Fund L.P. pursuant to a purchase option.

(2)    Obtained control of joint venture investment (see note 9).

Schedule of Finite-Lived Intangible Assets by Major Class [Table Text Block]

Intangible assets and liabilities recorded in connection with the above acquisition are set forth as follows:

			Weighted Average Amortization Period (in Years)
In-place leases	$	59,819	6.2
Tenant relations	24,828		4.6
Above-market leases	39,683		8.4
Total intangible assets acquired	$	124,330
Below-market leases	$	1,529	2.7

Schedule of Development Arrangements Outstanding [Table Text Block]

As of December 31, 2012, the Company had the following development arrangements outstanding:

Location	Property Type	Square Feet	Expected Maximum Commitment/Contribution ($ millions)		Estimated Purchase Price/Completion Cost ($ millions)		Lease Term (Years)	Estimated Completion Date
Long Island City, NY(1)	Industrial	143,000	$	46.7	$	55.5	15	1Q 13
Denver, CO	Office	163,000	$	38.4	$	38.4	15	2Q 13
Tuscaloosa, AL	Retail	42,000	$	8.8	$	8.8	15	2Q 13
Rantoul, IL	Industrial	813,000	$	42.6	$	42.6	20	4Q 13
		1,161,000	$	136.5	$	145.3

(1) Joint venture investment. The Company has guaranteed completion to the ground owner. The guarantee obligation was valued at $1,500 and is included in accounts payable and other liabilities in the Consolidated Balance Sheet. In addition, the Company may loan a maximum of $4,398 to the joint venture under certain circumstances. The difference between the Company's expected contribution and the estimated completion cost represents the joint venture partner's equity.