Fair Value Disclosures (Other Secured Financings Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Transfers of loans accounted for as secured financings	$ 0.0	$ 7.8

Transfers of loans accounted for as secured financings

No definition available.

Name:	luk_TransfersOfLoansAccountedForAsSecuredFinancings
Namespace Prefix:	luk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant