Commitments, Contingencies And Guarantees (Guarantees) (Details) - Notional [Member] $ in Millions	Dec. 31, 2015 USD ($)
Derivative Contracts - Non-Credit Related [Member]
Guarantor Obligations [Line Items]
2015	$ 11,840.6
2016	584.6
2017 and 2018	142.8
2019 and 2020	0.0
2021 and Later	414.4
Maximum Payout	12,982.4
Written Derivative Contracts - Credit Related [Member]
Guarantor Obligations [Line Items]
2015	0.0
2016	0.0
2017 and 2018	115.4
2019 and 2020	955.4
2021 and Later	10.0
Maximum Payout	1,080.8
Total Derivative Contracts [Member]
Guarantor Obligations [Line Items]
2015	11,840.6
2016	584.6
2017 and 2018	258.2
2019 and 2020	955.4
2021 and Later	424.4
Maximum Payout	$ 14,063.2

Guarantees with a remaining term that matures during the fiscal year. These may include derivative guarantees, etc.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Guarantees expected to be due within 5 to 6 fiscal years. These may include, derivative guarantees, etc.

+ References

No definition available.

+ Details

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Namespace Prefix:	luk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Guarantees expected to be due within 3 to 4 fiscal years. These may include, derivative guarantees, etc.

+ References

No definition available.

+ Details

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Namespace Prefix:	luk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Guarantees expected to be due within 2 fiscal years. These may include, derivative guarantees, etc.

+ References

No definition available.

+ Details

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Namespace Prefix:	luk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Guarantees expected to be due within 7 fiscal years and thereafter. These may include, derivative guarantees, etc

+ References

No definition available.

+ Details

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Namespace Prefix:	luk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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Period Type:	instant

- Details

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- Details

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- Details

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- Details

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