Number of individual fixed maturity securities in unrealized loss position.

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.

+ Details

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- 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=75027294&loc=d3e22002-158495

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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. Additionally, this item may include, if not separately presented, any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt securities which are being or have been recognized in earnings during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (c)
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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
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-Paragraph 28
-Subparagraph (b)
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-Topic 320
-SubTopic 10
-Section 35
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=82895926&loc=d3e25351-111560

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- Definition

Amount of cash inflow from the sale or maturity of long-term held-to-maturity securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02(2))
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Investments - Additional Information (Detail)	12 Months Ended
Investments - Additional Information (Detail)	Dec. 31, 2017 USD ($) Security	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Investment [Line Items]
Short-term investments	$ 25,770,000	$ 29,580,000
Sale of securities classified as held to maturity		3,000,000
Gain of held-to-maturity investment securities		100,000
Individual fixed maturity held in unrealized loss position \| Security	299
Individual fixed maturity held in unrealized loss position longer than 12 months \| Security	61
Impairment losses recognized	$ 0		$ 2,653,000
Held-to-Maturity Securities [Member]
Investment [Line Items]
Investments on deposit with regulatory agencies	18,700,000
Available-for-Sale Securities [Member]
Investment [Line Items]
Investments on deposit with regulatory agencies	2,400,000
Corporate Bonds [Member]
Investment [Line Items]
Short-term investments		2,800,000
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Investment [Line Items]
Short-term investments	$ 25,800,000	21,900,000
States and Political Subdivisions [Member]
Investment [Line Items]
Short-term investments		$ 4,900,000