Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Guarantor Obligations [Line Items]
Funds held by reinsured companies	$ 1,190,899	$ 109,358
Original commitments to investment funds	380,000
Commitments, funded	241,600
Commitments, unfunded	138,400
Limited Parental Guarantee
Guarantor Obligations [Line Items]
Total parental guarantees	501,700	$ 334,200
Reinsurance Recoverables \| Reinsurer Concentration Risk
Guarantor Obligations [Line Items]
Funds held by reinsured companies	$ 1,100,000

Fair Value Investments, Entities That Calculate Net Asset Value Per Share, Commitments

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- Definition

Fair Value Investments, Entities That Calculate Net Asset Value Per Share, Funded Commitments

+ References

No definition available.

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- Definition

The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=SL6742756-110258

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- Definition

Amount of the reinsurer's funds held on its behalf by the ceding insurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.2,10)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ 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 (c)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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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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