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Fixed Maturity Securities In An Unrealized Loss Position (Non-Investment Grade Fixed Maturity Securities) (Details) $ in Thousands	Mar. 31, 2021 USD ($) position	Dec. 31, 2020 USD ($)
Corporate
Debt Securities, Available-for-sale [Line Items]
Aggregate Fair Value	$ 1,527,951	$ 652,162
Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Aggregate Fair Value	352,947	236,331
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Aggregate Fair Value	$ 2,456,038	$ 2,046,010
Noninvestment Grade Investments at Loss Position
Debt Securities, Available-for-sale [Line Items]
Number of Securities | position	32
Aggregate Fair Value	$ 105,367
Gross Unrealized Loss	$ 41,789
Noninvestment Grade Investments at Loss Position | Foreign government
Debt Securities, Available-for-sale [Line Items]
Number of Securities | position	19
Aggregate Fair Value	$ 79,761
Gross Unrealized Loss	$ 39,694
Noninvestment Grade Investments at Loss Position | Corporate
Debt Securities, Available-for-sale [Line Items]
Number of Securities | position	8
Aggregate Fair Value	$ 25,066
Gross Unrealized Loss	$ 2,071
Noninvestment Grade Investments at Loss Position | Mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Number of Securities | position	5
Aggregate Fair Value	$ 540
Gross Unrealized Loss	$ 24

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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

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563

+ Details

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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.

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- Definition

Available For Sale Equity Securities Continuous Unrealized Loss Position Aggregate Loss

+ References

No definition available.

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