Amortization Cost Of Investment In Fixed Maturities Rated Below Investment Grade

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- Definition

Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Increase (Decrease) In Accumulated Loss

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No definition available.

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- Definition

Total issues of fixed maturities.

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No definition available.

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- Definition

Fair Value Of Investment In Fixed Maturities Rated Below Investment Grade

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No definition available.

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- Definition

Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Net of Tax

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No definition available.

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- Definition

Par Value Of Investment In Fixed Maturities Rated Below Investment Grade

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No definition available.

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- Definition

Percentage Of Fixed Maturities At Fair Value, Written Down Securities

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No definition available.

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- Definition

Percentage Of Invested Assets Rated Below Investment Grade

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No definition available.

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- Definition

Proportion Of State And Municipal Governments Securities At Fair Value In Investment Portfolio

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No definition available.

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- Definition

Securities, Cash And Short-Term Investments, Amortized Cost

+ References

No definition available.

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- Definition

Securities, Cash And Short-Term Investments Held As Collateral, At Fair Value

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No definition available.

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- Definition

Written Down Securities Carried At Fair Value

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No definition available.

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- References

No definition available.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

+ References

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Investments - Additional Information (Detail)	12 Months Ended
Investments - Additional Information (Detail)	Dec. 31, 2019 USD ($) Issue	Dec. 31, 2018 USD ($) Issue	Dec. 31, 2017 USD ($)
Investment [Line Items]
Fixed maturity portfolio issues \| Issue	1,633	1,548
Gross unrealized losses	$ (83,235,000)	$ (428,379,000)
Increase (decrease) in gross unrealized losses	(345,000,000)
Other-than-temporary impairment	0	0	$ 245,000
Other-than-temporary impairment, net of tax			$ 159,000
Written down securities, fair value	$ 61,000,000
Written down securities, percentage of fair value of fixed maturity portfolio	0.40%
State and municipal governments, percent of invested assets at fair value	9.00%
Percentage of invested assets rated below investment grade	3.00%
Concentration risk percentage	100.00%
Par value of investments rated below investment grade	$ 768,000,000
Amortized cost of investments rated below investment grade	674,000,000
Fair value of investments rated below investment grade	645,000,000
Securities, cash, and short-term investments, amortized cost	816,000,000	712,000,000
Securities, cash, and short-term investments, fair value	$ 956,000,000	$ 763,000,000
Investment portfolio \| Credit Concentration Risk \| Corporates
Investment [Line Items]
Concentration risk percentage	83.00%
Texas
Investment [Line Items]
State and municipal governments, percent of invested assets at fair value	22.00%
Michigan
Investment [Line Items]
State and municipal governments, percent of invested assets at fair value	8.00%
New York
Investment [Line Items]
State and municipal governments, percent of invested assets at fair value	7.00%
Florida
Investment [Line Items]
State and municipal governments, percent of invested assets at fair value	6.00%
Ohio
Investment [Line Items]
State and municipal governments, percent of invested assets at fair value	5.00%
Fixed maturities available for sale
Investment [Line Items]
Concentration risk percentage	95.00%
Investment funds \| Minimum
Investment [Line Items]
Investment funds ownership percentage	1.00%
Investment funds \| Maximum
Investment [Line Items]
Investment funds ownership percentage	20.00%