Derivative Instruments - Gains (Losses) Related to Derivative and Hedge Items (Details) - Derivatives designated as hedges - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Fair Value Hedging \| Foreign currency forwards
Derivative [Line Items]
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net, Recorded in Other Comprehensive Income	$ 20,000,000	$ (22,000,000)	$ 0
Fair Value Hedging \| Swaps
Derivative [Line Items]
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net, Recorded in Other Comprehensive Income	88,000,000	0	0
Fair Value Hedging \| Investment related gains (losses) \| Foreign currency forwards
Derivative [Line Items]
Derivatives	183,000,000	420,000,000	(118,000,000)
Hedged Items	(190,000,000)	(440,000,000)	116,000,000
Net	(7,000,000)	(20,000,000)	(2,000,000)
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Amortization Approach	67,000,000	21,000,000	0
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net	9,000,000	16,000,000	0
Fair Value Hedging \| Investment related gains (losses) \| Swaps
Derivative [Line Items]
Derivatives	(622,000,000)	(102,000,000)	1,000,000
Hedged Items	632,000,000	99,000,000	(1,000,000)
Net	10,000,000	(3,000,000)	0
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Amortization Approach	0	0	0
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net	0	0	0
Fair Value Hedging \| Investment related gains (losses) \| Cross Currency Interest Rate Contract
Derivative [Line Items]
Derivatives	(332,000,000)	(1,000,000)
Hedged Items	323,000,000	1,000,000
Net	(9,000,000)	0
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Amortization Approach	0	0
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net	0	0
Fair Value Hedging \| Investment related gains (losses) \| Interest rate swaps
Derivative [Line Items]
Derivatives
Hedged Items
Net
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Amortization Approach
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net
Fair Value Hedging \| Interest sensitive contract benefits \| Cross Currency Interest Rate Contract
Derivative [Line Items]
Derivatives	52,000,000	23,000,000
Hedged Items	(53,000,000)	(21,000,000)
Net	(1,000,000)	2,000,000
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Amortization Approach	0	0
Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net	0	0
Cash flow hedges \| Swaps
Derivative [Line Items]
Foreign currency swap gain (loss) reclassified to income	0	14,000,000	0
Foreign currency swap gains (losses)	0	254,000,000	(106,000,000)
Cash flow hedges \| Interest rate swaps
Derivative [Line Items]
Foreign currency swap gains (losses)	$ (106,000,000)	$ 0	$ 0

Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Amortization Approach

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- Definition

Gain (Loss) from Components Excluded from Assessment of Fair Value Hedge Effectiveness, Net, Recorded in Other Comprehensive Income

+ References

No definition available.

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- Definition

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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- Definition

Amount of gain (loss) on derivative instrument designated and qualifying as fair value hedge included in assessment of hedge effectiveness, recognized in earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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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.

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- Definition

The amount of net gains or losses on foreign currency cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
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- Definition

Net gain (loss) relating to components of the gain (loss) on the fair value hedging instrument excluded from the assessment of fair value hedge effectiveness. Recognized in earnings.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of net unrealized gain (loss) related to the change in fair value of foreign currency exchange rate derivatives designated as cash flow hedging instruments. Recorded in accumulated other comprehensive income to the extent that the cash flow hedge is determined to be effective.

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