Investments (Credit Losses Recognized In Earnings on Fixed Maturity Securities Held by the Company) (Details) - Fixed maturities - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Balance, beginning of period	$ 686	$ 0
Additions to allowance for credit losses not previously recorded	432	186
Reductions for securities sold during the period	(6)
Addition (reductions) on securities with previous allowance	(377)
Balance, end of period	735	186
U.S. Treasury securities and obligations of U.S. government authorities and agencies
Debt Securities, Available-for-sale [Line Items]
Balance, beginning of period	0	0
Additions to allowance for credit losses not previously recorded	0	0
Reductions for securities sold during the period	0
Addition (reductions) on securities with previous allowance	0
Balance, end of period	0	0
Foreign government bonds
Debt Securities, Available-for-sale [Line Items]
Balance, beginning of period	0	0
Additions to allowance for credit losses not previously recorded	0	0
Reductions for securities sold during the period	0
Addition (reductions) on securities with previous allowance	0
Balance, end of period	0	0
U.S. and Foreign Corporate Securities
Debt Securities, Available-for-sale [Line Items]
Balance, beginning of period	686	0
Additions to allowance for credit losses not previously recorded	432	186
Reductions for securities sold during the period	(6)
Addition (reductions) on securities with previous allowance	(377)
Balance, end of period	735	186
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Balance, beginning of period	0	0
Additions to allowance for credit losses not previously recorded	0	0
Reductions for securities sold during the period	0
Addition (reductions) on securities with previous allowance	0
Balance, end of period	0	0
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Balance, beginning of period	0	0
Additions to allowance for credit losses not previously recorded	0	0
Reductions for securities sold during the period	0
Addition (reductions) on securities with previous allowance	0
Balance, end of period	0	0
Residential mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Balance, beginning of period	0	0
Additions to allowance for credit losses not previously recorded	0	0
Reductions for securities sold during the period	0
Addition (reductions) on securities with previous allowance	0
Balance, end of period	$ 0	$ 0

This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which no such other than temporary impairment (OTTI) was previously recognized.

Name:	us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=SL6284393-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=SL6284393-111563

+ Details

Name:	us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of increase (decrease) in the cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-URI http://asc.fasb.org/extlink&oid=121645371&loc=SL6284393-111563

+ Details

Name:	us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because of the sale of impaired securities during the period.

+ References

+ Details

Name:	us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

Name:	us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_FixedMaturitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ForeignGovernmentDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommercialMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: