Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended			6 Months Ended			6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010	Jun. 30, 2011 Public Offering And Direct Share Purchase Plan Proceeds [Member]	Jun. 30, 2010 Public Offering And Direct Share Purchase Plan Proceeds [Member]	Mar. 31, 2010 Six Percent Convertible Guaranteed Note [Member]	Jun. 30, 2011 Accumulated Distributions in Excess of Net Income [Member]	Jun. 30, 2010 Accumulated Distributions in Excess of Net Income [Member]
Equity [Line Items]
Common shares issued through public offering and direct share purchase plan during period			10,515,548	11,736,433
Proceeds from issuance of common shares			$ 90,573	$ 70,698		$ 94,761	$ 76,217
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt				13,134						0
Debt Instrument, Interest Rate, Stated Percentage								6.00%
Unrealized gain (loss) on interest rate swap in Accumulated Other Comprehensive Income	670		670		(106)
OP Unit Equivalent in Common Shares			1.13
Partners' Capital Account, Units, Redeemed			172,130	112,620
OP Units Outstanding	4,208,000		4,208,000
Partners Capital Units With Liquidation Preference Number			0
Transfers from noncontrolling interests:
Net loss attributable to Lexington Realty Trust shareholders	(56,957)	(29,701)	(72,950)	(59,027)					(61,697)	(50,868)
Increase in additional paid-in-capital for redemption of noncontrolling OP units			1,077	687
Change from net loss attributable to shareholders and transfers from noncontrolling interest			$ (60,620)	$ (50,181)