The cumulative before tax amount of the reporting entity's undistributed earnings or deficit.

No definition available.

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Amount of tax expense (benefit) allocated to the reporting entity's undistributed earnings or deficit.

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No definition available.

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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- Definition

Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, attributable to parent. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners).

+ References

No definition available.

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Amount of tax expense (benefit) allocated to accumulated other comprehensive income (loss) attributable to parent.

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No definition available.

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- 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.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Nature of Operations and Significant Accounting Policies - Cumulative effect adjustment to retained earnings and AOCI (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2020
Recent Accounting Pronouncements
Increase (Decrease) Retained earnings, After-Tax	$ 16,398.8	$ 16,697.3
Increase (Decrease) Accumulated other comprehensive income, After-Tax	$ (6,201.3)	$ (6,879.0)
Cumulative effect adjustment \| Adjustment for reversal of unrealized gain (loss) from AOCI \| DAC and other actuarial balances
Recent Accounting Pronouncements
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			$ 421.5
Increase (Decrease) Accumulated other comprehensive income, Tax			(88.5)
Increase (Decrease) Accumulated other comprehensive income, After-Tax			333.0
Cumulative effect adjustment \| Adjustment for reversal of unrealized gain (loss) from AOCI \| Reinsurance recoverables
Recent Accounting Pronouncements
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			(45.5)
Increase (Decrease) Accumulated other comprehensive income, Tax			9.5
Increase (Decrease) Accumulated other comprehensive income, After-Tax			(36.0)
Cumulative effect adjustment \| Adjustment for reversal of unrealized gain (loss) from AOCI \| Liability for future policy benefits
Recent Accounting Pronouncements
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			1,965.3
Increase (Decrease) Accumulated other comprehensive income, Tax			(452.2)
Increase (Decrease) Accumulated other comprehensive income, After-Tax			1,513.1
Cumulative effect adjustment \| Adjustment under the modified retrospective approach \| Reinsurance recoverables
Recent Accounting Pronouncements
Increase (Decrease) Retained earnings, Pre-Tax			31.4
Increase (Decrease) Retained earnings, Tax			(6.6)
Increase (Decrease) Retained earnings, After-Tax			24.8
Cumulative effect adjustment \| Adjustment under the modified retrospective approach \| Liability for future policy benefits
Recent Accounting Pronouncements
Increase (Decrease) Retained earnings, Pre-Tax			(119.1)
Increase (Decrease) Retained earnings, Tax			29.8
Increase (Decrease) Retained earnings, After-Tax			(89.3)
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			17.9
Increase (Decrease) Accumulated other comprehensive income, Tax			(4.8)
Increase (Decrease) Accumulated other comprehensive income, After-Tax			13.1
Cumulative effect adjustment \| Effect of remeasurement at the current discount rate \| Reinsurance recoverables
Recent Accounting Pronouncements
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			201.8
Increase (Decrease) Accumulated other comprehensive income, Tax			(42.4)
Increase (Decrease) Accumulated other comprehensive income, After-Tax			159.4
Cumulative effect adjustment \| Effect of remeasurement at the current discount rate \| Liability for future policy benefits
Recent Accounting Pronouncements
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			(9,043.1)
Increase (Decrease) Accumulated other comprehensive income, Tax			2,024.8
Increase (Decrease) Accumulated other comprehensive income, After-Tax			(7,018.3)
Cumulative effect adjustment \| Investment in equity method subsidiary impacted by LDTI \| Other investments
Recent Accounting Pronouncements
Increase (Decrease) Retained earnings, Pre-Tax			22.8
Increase (Decrease) Retained earnings, Tax			(9.1)
Increase (Decrease) Retained earnings, After-Tax			13.7
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			(25.5)
Increase (Decrease) Accumulated other comprehensive income, Tax			10.2
Increase (Decrease) Accumulated other comprehensive income, After-Tax			(15.3)
Cumulative effect adjustment \| Cumulative effect of amortization basis change \| Cost of reinsurance asset (liability)
Recent Accounting Pronouncements
Increase (Decrease) Retained earnings, Pre-Tax			(9.0)
Increase (Decrease) Retained earnings, Tax			1.9
Increase (Decrease) Retained earnings, After-Tax			(7.1)
Cumulative effect adjustment \| Adjustment of unrealized loss in AOCI \| Cost of reinsurance asset (liability)
Recent Accounting Pronouncements
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			16.1
Increase (Decrease) Accumulated other comprehensive income, Tax			(3.4)
Increase (Decrease) Accumulated other comprehensive income, After-Tax			12.7
Cumulative effect adjustment \| Cumulative effect of changes in the nonperformance risk between the original contract issue date and the transition date \| Market risk benefits
Recent Accounting Pronouncements
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			(4.8)
Increase (Decrease) Accumulated other comprehensive income, Tax			1.0
Increase (Decrease) Accumulated other comprehensive income, After-Tax			(3.8)
Cumulative effect adjustment \| Adjustments to the host contract for differences between previous carrying amount and measurement of the MRB \| Market risk benefits
Recent Accounting Pronouncements
Increase (Decrease) Retained earnings, Pre-Tax			20.9
Increase (Decrease) Retained earnings, Tax			(4.4)
Increase (Decrease) Retained earnings, After-Tax			16.5
Cumulative effect adjustment \| Retained earnings adjustment for the valuation of contracts as MRBs (exclusive of nonperformance risk changes) \| Market risk benefits
Recent Accounting Pronouncements
Increase (Decrease) Retained earnings, Pre-Tax			(258.8)
Increase (Decrease) Retained earnings, Tax			54.4
Increase (Decrease) Retained earnings, After-Tax			(204.4)
Cumulative effect adjustment \| Reclassification of nonperformance risk changes between retained earnings and AOCI \| Market risk benefits
Recent Accounting Pronouncements
Increase (Decrease) Retained earnings, Pre-Tax			108.4
Increase (Decrease) Retained earnings, Tax			(22.5)
Increase (Decrease) Retained earnings, After-Tax			85.9
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			(108.4)
Increase (Decrease) Accumulated other comprehensive income, Tax			22.5
Increase (Decrease) Accumulated other comprehensive income, After-Tax			(85.9)
ASU 2018-12 - Targeted improvements to the accounting for long-duration insurance contracts \| Cumulative effect adjustment
Recent Accounting Pronouncements
Increase (Decrease) Retained earnings, Pre-Tax			(203.4)
Increase (Decrease) Retained earnings, Tax			43.5
Increase (Decrease) Retained earnings, After-Tax			(159.9)
Increase (Decrease) Accumulated other comprehensive income, Pre-Tax			(6,604.7)
Increase (Decrease) Accumulated other comprehensive income, Tax			1,476.7
Increase (Decrease) Accumulated other comprehensive income, After-Tax			$ (5,128.0)