Segment Information (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Segment Reporting Information [Line Items]
Net securities gains	$ 2,526	$ 529,637	$ 427,462	$ 531,940
Interest expense	21,373	27,837	50,241	56,814
Corporate [Member]
Segment Reporting Information [Line Items]
Interest expense	18,059		43,888
Beef Processing Services [Member]
Segment Reporting Information [Line Items]
Interest expense	3,284		6,300
Domestic Real Estate [Member]
Segment Reporting Information [Line Items]
Gain on forgiveness of debt				81,848
Leucadia Other Operations [Member]
Segment Reporting Information [Line Items]
Pre-tax losses of investigation and evaluation of various energy related projects	9,442	8,044	15,313	15,826
Government grants reimbursement		889		2,879
Fortescue [Member] | Corporate [Member]
Segment Reporting Information [Line Items]
Net securities gains		$ 527,351	$ 417,887	$ 527,351