Investments (Payables For Collateral On Investments) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Carrying Value
Collateral payable for derivative investments	$ 4,767	$ 5,565
Securities pledged under securities lending agreements	258	241
Investments pledged for Federal Home Loan Bank of Indianapolis ('FHLBI')	3,880	3,130
Total payables for collateral on investments	8,905	8,936
Fair Value
Collateral payable for derivative investments	4,767	5,565
Securities pledged under securities lending agreements	250	235
Investments pledged for Federal Home Loan Bank of Indianapolis('FHLBI')	5,924	4,876
Total payables for collateral on investments	$ 10,941	$ 10,676
Percentage of the fair value of domestic securities obtained as collateral under securities lending agreements.	102.00%
Percentage of the fair value of foreign securities obtained as collateral under securities lending agreements.	105.00%
Maximum [Member]
Fair Value
Percentage of the fair value of FHLBI securities obtained as collateral under securities pledged for FHLBI for AFS Securities	115.00%
Percentage of the fair value of FHLBI securities obtained as collateral under securities pledged for FHLBI for mortgage loan	175.00%
Minimum [Member]
Fair Value
Percentage of the fair value of FHLBI securities obtained as collateral under securities pledged for FHLBI for AFS Securities	105.00%
Percentage of the fair value of FHLBI securities obtained as collateral under securities pledged for FHLBI for mortgage loan	155.00%

Carrying Value Of Payables For Collateral On Investments [Abstract]

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This item represents the percentage of the fair value of AFS securities obtained as collateral pledged.

+ References

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- Definition

This item represents the percentage of the fair value of Mortgage loans obtained as collateral pledged.

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This item represents the percentage of the fair value of domestic securities obtained as collateral under securities lending agreements

+ References

No definition available.

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This item represents the percentage of the fair value of foreign securities obtained as collateral under securities lending agreements

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No definition available.

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- Definition

When entering into a derivative transaction, the amount of cash received as collateral from a counterparty.

+ References

No definition available.

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The fair value of cash received as collateral from a counterparty.

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- Definition

Fair Value Of Related Investments Or Collateral [Abstract]

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- Definition

The amount of cash received as security in return for loaning securities to Federal Home Loan Bank of Indianapolis.

+ References

No definition available.

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- Definition

The fair value of investments loaned to Federal Home Loan Bank of Indianapolis as of the balance sheet date.

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No definition available.

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- Definition

The fair value of investments loaned to another party under securities lending agreements as of the balance sheet date.

+ References

No definition available.

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- Definition

The total fair value of investments related to payables for collateral on investments as of the balance sheet date.

+ References

No definition available.

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- Definition

The amount of cash received as security in return for loaning securities to another party.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(11))
-URI http://asc.fasb.org/extlink&oid=120401414&loc=d3e603758-122996

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Amount, before effects of master netting arrangements, of financial assets loaned to entities in exchange for collateral and funds outstanding borrowed in the form of a financial asset repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same financial assets at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 7
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

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