CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 97,463us-gaap_ProfitLoss	$ 3,863us-gaap_ProfitLoss	$ 184,638us-gaap_ProfitLoss
Other comprehensive income (loss):
Change in unrealized gain (loss) on interest rate swaps, net	(4,035)	10,663	(8,162)
Other comprehensive income (loss)	(4,035)	10,663	(8,162)
Comprehensive income	93,428	14,526	176,476
Comprehensive income attributable to noncontrolling interests	(4,359)	(2,233)	(4,322)
Comprehensive income attributable to Lexington Realty Trust shareholders	$ 89,069us-gaap_ComprehensiveIncomeNetOfTax	$ 12,293us-gaap_ComprehensiveIncomeNetOfTax	$ 172,154us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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