Investments - Additional Information (Detail) (USD $)	3 Months Ended
Mar. 31, 2014 Individual Equity	Mar. 31, 2013
Investments Schedule [Abstract]
Individual fixed maturity held in unrealized loss position	144
Equity securities held in unrealized loss position	1
Individual fixed maturity held in unrealized loss position	27
Carrying value of investments	$ 10,800,000
Net realized investment gains (losses)	100,000
Impairment losses recognized	$ 0	$ 0

Equity Method Investments Investment Carrying Value

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- Definition

Number of Equity Securities in Unrealized Loss Position

+ References

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- Definition

Number Of Individual Fixed Maturity Securities In Unrealized Loss Position

+ References

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- Definition

Number of Individual Investment Securities in Unrealized Loss Position Greater Than Twelve Months

+ References

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- Definition

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26805-111562

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e25351-111560

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