Additional contractual commitments

No definition available.

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- Definition

Contractual commitments, investment period expiration date

+ References

No definition available.

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- Definition

Percentage threshold that triggers a review of available for sale debt securities for declines in market value.

+ References

No definition available.

+ Details

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- Definition

Reclassification From Other Invested Assets To Fixed Maturity Securities

+ References

No definition available.

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- Definition

Reclassification of other invested assets to short-term investments.

+ References

No definition available.

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- Definition

Investments in notes or bonds that are collateralized by a specific group of underlying assets owned by the issuer of the notes or bonds which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

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- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

+ References

No definition available.

+ Details

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- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

+ Details

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- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months.

+ References

No definition available.

+ Details

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
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- Definition

This element represents the excess of the cost (face amount, notional amount) of an investment (security, contract) over its fair value which deficiency has not been recognized in earnings of the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=50485924&loc=SL6090603-123010

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Investments (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
Investments (Narrative) (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Percentage threshold that triggers a review of available for sale debt securities for declines in market value			80.00%
Additional contractual commitments		$ 1,016,811,000
Contractual commitments, investment period expiration date		Jan. 01, 2026
Reclassification of other invested assets to fixed maturity securities	$ 143,656,000
Reclassification of other invested assets to short-term investments	$ 243,864,000
Securities, carrying value		$ 1,549,145,000
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Aggregate market value of investments in unrealized loss position		3,639,991,000	$ 9,814,849,000
Gross unrealized losses on investments in unrealized loss position		121,169,000	367,898,000
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation		26,793,000	120,838,000
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation		94,376,000	247,060,000
Gross unrealized depreciation			367,898,000
Market value of investments		$ 16,824,944,000	$ 15,225,263,000
Fixed Maturity Securities [Member] \| Sales Revenue, Net [Member]
Schedule of Available-for-sale Securities [Line Items]
Percentage threshold that triggers a review of available for sale debt securities for declines in market value			1.00%
Fixed Maturity Securities [Member] \| US Government Securities [Member] \| Sales Revenue, Net [Member]
Schedule of Available-for-sale Securities [Line Items]
Percentage threshold of unrealized losses not exceeded by any one single issuer		0.80%	5.70%
Investment Grade [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed maturity securities, duration of unrealized loss, less than 12 months, gross unrealized depreciation		$ 23,104,000	$ 74,729,000
Fixed maturity securities, duration of unrealized loss, greater than 12 months, gross unrealized depreciation		73,144,000	230,560,000
Sub-prime and Alt-A Loans [Member]
Schedule of Available-for-sale Securities [Line Items]
Gross unrealized depreciation		0	$ 0
Private Placement Liquidity Sweep [Member]
Schedule of Available-for-sale Securities [Line Items]
Market value of investments		$ 308,711,000