Insurance Liabilities - Components of Contractholder Funds (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Liabilities for investment contracts:
Liabilities for individual annuities	$ 12,864.1	$ 13,457.5
GICs	11,858.0	10,423.5
Funding agreements	9,407.3	8,640.6
Other investment contracts	1,762.4	1,596.7
Total liabilities for investment contracts	35,891.8	34,118.3
Universal life and other reserves	7,345.9	7,249.2
Contractholder funds	$ 43,237.7	$ 41,367.5

Contractholder funds include reserves for investment contracts and reserves for universal life insurance.

No definition available.

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- Definition

Carrying amount of liabilities as of the balance sheet date pertaining to amounts received by the insurer for investment contracts not otherwise specified in the taxonomy.

+ References

No definition available.

+ Details

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- Definition

The amount of the liability as of the balance sheet date pertaining to amounts received by the insurer for funding agreements.

+ References

No definition available.

+ Details

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- Definition

The amount of the liability as of the balance sheet date pertaining to liabilities for individual annuities.

+ References

No definition available.

+ Details

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- Definition

The amount as of the balance sheet date pertaining to reserves for universal life and other reserves.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of liabilities as of the balance sheet date pertaining to amounts received by the insurer or reinsurer from the insured (including a ceding company) under insurance or reinsurance contracts for which insurance risk is not transferred.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99383045&loc=d3e9351-108337

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99397363&loc=d3e9420-108338

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- References

No definition available.

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- Definition

The amount of the liability as of the balance sheet date pertaining to the guarantee given by the insurance entity to contract holders of a specified rate of return (a guaranteed yield) on their investments for a specified period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(14))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(13))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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