Equity - Effects of Changes in Noncontrolling Interests (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Equity [Abstract]
Net income attributable to Lexington Realty Trust shareholders	$ 143,319	$ 218,016	$ 194,679	$ 202,007
Transfers from noncontrolling interests:
Increase in additional paid-in-capital for redemption of noncontrolling OP units			504	63
Change from net income attributable to shareholders and transfers from noncontrolling interests			$ 195,183	$ 202,070