Acquisitions (Pro Forma Operating Results) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2011
Acquisitions [Abstract]
Revenues and other income	$ 2,526,860	$ 4,463,740
Net income attributable to Leucadia National Corporation common shareholders	$ 212,219	$ 248,421
Basic earnings per common share attributable to Leucadia National Corporation common shareholders	$ 0.87	$ 1.02
Diluted earnings per common share attributable to Leucadia National Corporation common shareholders	$ 0.85	$ 1.00