Borrowings and Financing Activities - Narrative (Details) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
FHLB advances, carrying value	$ 148,983	$ 150,983
FHLB, maturity period, fixed rate	90 days
FHLB advances
FHLB advances, carrying value	$ 148,983	150,983
FHLB, weighted average interest rate	0.98%
Revolving Credit Facility
Current borrowing capacity	$ 275,000
Fair value of amount outstanding	$ 0
Minimum \| FHLB advances
FHLB, ratio of market value of collateral to advances	1.03
Maximum \| FHLB advances
FHLB, ratio of market value of collateral to advances	1.14
Fixed maturities AFS and trading securities \| Debt securities
FHLB, collateral pledged	$ 190,000	$ 167,300

The ratio of the market value of the collateralized eligible assets to the principal balance of the FHLB advances

No definition available.

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

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- Definition

Maturity period on fixed rate advances made and reported by Federal Home Loan Bank (FHLBank), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank).

+ References

No definition available.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

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