Investments - Sales of Fixed Maturities and Equity Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Proceeds received	$ 472,913	$ 805,887	$ 625,527
Gross gains realized	20,470	150,852	10,536
Gross losses realized	(6,072)	(7,807)	(14,932)
Proceeds received	12,717	29,863	25,498
Gross gains realized	2,197	9,193	8,592
Gross losses realized	(1,885)	$ (788)	$ (917)
Investment gain realized on transfer	$ 135,300
Reinsurance block of in-force fixed and variable annuity business				$ 2,900,000

Investment Gain (Loss) On Reinsurance

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- Definition

Proceeds From Sale And Maturity Of Marketable Securities (Excluding FHLB Repayments)

+ References

No definition available.

+ Details

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- Definition

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563

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- Definition

Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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- Definition

Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117546-209714

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- Definition

Amount of realized loss from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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- References

No definition available.

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- Definition

Amount of cash inflow from sale, maturity, prepayment and call of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3151-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26853-111562

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- Definition

Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

No definition available.

+ Details

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