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.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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- Definition

Amount of gain (loss) on sale of investment in debt security measured at amortized cost (held-to-maturity), including other-than-temporary impairment (OTTI).

+ References

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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

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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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- Definition

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

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Investments - Additional Information (Detail)	12 Months Ended
Investments - Additional Information (Detail)	Dec. 31, 2018 USD ($) Security	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Investment [Line Items]
Short-term investments	$ 14,231,000	$ 25,770,000
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	398
Individual fixed maturity held in unrealized loss position longer than 12 months \| Security	323
Impairment losses recognized	$ 0	0	$ 0
Held-to-Maturity Securities [Member]
Investment [Line Items]
Investments on deposit with regulatory agencies	16,100,000
Available-for-Sale Securities [Member]
Investment [Line Items]
Investments on deposit with regulatory agencies	2,500,000
Corporate Bonds [Member]
Investment [Line Items]
Short-term investments	13,400,000
States and Political Subdivisions [Member]
Investment [Line Items]
Short-term investments	$ 800,000
U.S. Treasury Securities and Obligations of U.S. Government Agencies [Member]
Investment [Line Items]
Short-term investments		$ 25,800,000