Investments - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2014 Individual	Dec. 31, 2013
Investment [Line Items]
Short term debt	$ 33,684,000us-gaap_ShortTermInvestments	$ 84,422,000us-gaap_ShortTermInvestments
Carrying value of investments	11,700,000
Held to maturity investments	19,800,000us-gaap_AssetsHeldByInsuranceRegulators
Individual fixed maturity held in unrealized loss position	174
Individual fixed maturity held in unrealized loss position	19
Impairment losses recognized	222,000us-gaap_ImpairmentOfInvestments
Net carrying value of security held	2,100,000
Sale of security loss realized	58,000
Fixed Maturity Securities Available for Sale [Member]
Investment [Line Items]
Impairment losses recognized	222,000
Corporate Bonds [Member]
Investment [Line Items]
Short term debt	32,700,000	82,700,000
Certificates of Deposit [Member]
Investment [Line Items]
Short term debt	1,000,000	900,000
Municipal Securities [Member]
Investment [Line Items]
Short term debt		$ 800,000

Equity method investments investment carrying value.

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- Definition

For any redemption o.f of securities categorized as held to maturity, this item represents the net carrying amount of the redeemed security.

+ References

No definition available.

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- Definition

This item represents the gain (loss) realized on the sale of held to maturity securities disposed of during the period.

+ References

No definition available.

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- Definition

Number of individual fixed maturity securities in unrealized loss position.

+ References

No definition available.

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- Definition

Number of individual investment securities in unrealized loss position greater than twelve months.

+ References

No definition available.

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- Definition

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 320

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=28366721&loc=d3e22002-158495

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34

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- Definition

Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy.

+ 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 210.5-02.2)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph g

-Article 7

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