Contingencies and Commitments - Narrative (Detail)	3 Months Ended
Mar. 31, 2016 USD ($)
Berkadia Commercial Mortgage (investee) [Member]
Commitments and Contingencies [Line Items]
Voting interest in investee	50.00%
Commercial paper outstanding	$ 1,470,000,000
Berkadia Commercial Mortgage (investee) [Member] \| Commercial Paper [Member]
Commitments and Contingencies [Line Items]
Maximum outstanding balance of commercial paper borrowings	$ 1,500,000,000
Berkadia Commercial Mortgage (investee) [Member] \| Leucadia National Corporation (venture partner) [Member]
Commitments and Contingencies [Line Items]
Voting interest in investee	50.00%
Berkshire Hathaway Insurance Group [Member]
Commitments and Contingencies [Line Items]
Reimbursement rate from joint venture partner of Company's surety bond claim losses	50.00%

The recovery percentage of the entity's surety bond claim losses that its joint venture partner is obligated to pay.

No definition available.

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- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(a)(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(2))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 7

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- 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.

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- Details

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- Details

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- Details

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