Fixed Maturity Securities In An Unrealized Loss Position (Non-Investment Grade Fixed Maturity Securities) (Details) $ in Thousands	Jun. 30, 2021 USD ($) position	Dec. 31, 2020 USD ($)
Corporate
Debt Securities, Available-for-sale [Line Items]
Aggregate Fair Value	$ 1,016,438	$ 652,162
Mortgage-backed
Debt Securities, Available-for-sale [Line Items]
Aggregate Fair Value	296,533	236,331
Asset-backed
Debt Securities, Available-for-sale [Line Items]
Aggregate Fair Value	$ 3,188,360	$ 2,046,010
Noninvestment Grade Investments at Loss Position
Debt Securities, Available-for-sale [Line Items]
Number of Securities \| position	42
Aggregate Fair Value	$ 145,781
Gross Unrealized Loss	$ 32,249
Noninvestment Grade Investments at Loss Position \| Foreign government
Debt Securities, Available-for-sale [Line Items]
Number of Securities \| position	27
Aggregate Fair Value	$ 108,910
Gross Unrealized Loss	$ 30,171
Noninvestment Grade Investments at Loss Position \| Corporate
Debt Securities, Available-for-sale [Line Items]
Number of Securities \| position	10
Aggregate Fair Value	$ 36,482
Gross Unrealized Loss	$ 2,058
Noninvestment Grade Investments at Loss Position \| Mortgage-backed
Debt Securities, Available-for-sale [Line Items]
Number of Securities \| position	4
Aggregate Fair Value	$ 276
Gross Unrealized Loss	$ 19
Noninvestment Grade Investments at Loss Position \| Asset-backed
Debt Securities, Available-for-sale [Line Items]
Number of Securities \| position	1
Aggregate Fair Value	$ 113
Gross Unrealized Loss	$ 1

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.

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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=121645371&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.

+ Details

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- Definition

Available For Sale Equity Securities Continuous Unrealized Loss Position Aggregate Loss

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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