Loans To And Investments In Associated Companies (Jefferies LoanCore) (Narrative) (Details) (Jefferies LoanCore [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Jefferies LoanCore [Member]
Aggregate equity commitment	$ 600.0
Equity commitment	291.0
Funded Equity Commitments	$ 193.4
Percentage of voting interest	48.50%

The voting percentage of common stock or equity participation in the investee accounted for under the equity method of accounting.

No definition available.

Name:	luk_EquityMethodInvestmentVotingPercentage
Namespace Prefix:	luk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration