Valuation and Qualifying Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Allowance for uncollectable reinsurance
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at January 1, 2014	$ 11,332
Charged to Other Accounts	0
Deductions (Describe)	0
Balance at December 31, 2014	11,332
Valuation allowance in deferred taxes
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at January 1, 2014	554
Charged (Credited) to Costs and Expenses	222
Charged to Other Accounts	0
Deductions (Describe)	0
Balance at December 31, 2014	$ 776

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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