Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Equity [Line Items]
Common shares issued through public offering and direct share purchase plan during period	298,662	277,044
Proceeds from issuance of common shares	$ 2,145	$ 2,070
Unrealized gain (loss) on interest rate swap in Accumulated Other Comprehensive Income	1,882		1,938
OP Unit Equivalent in Common Shares	1.13
Partners Capital Account, Shares Issued For Units Redeemed		60,980
OP Units Outstanding	4,026,000
Transfers from noncontrolling interests:
Net income (loss) attributable to Lexington Realty Trust shareholders	3,611	(17,439)
Increase in additional paid-in-capital for redemption of noncontrolling OP units	0	343
Change from net income (loss) attributable to shareholders and transfers from noncontrolling interest	3,611	(17,096)
Accumulated Distributions in Excess of Net Income [Member]
Transfers from noncontrolling interests:
Net income (loss) attributable to Lexington Realty Trust shareholders	3,611	(17,439)
Public Offering And Direct Share Purchase Plan Proceeds [Member]
Equity [Line Items]
Proceeds from issuance of common shares	$ 2,145	$ 2,084