INCOME TAXES - Provision for Income Taxes Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income tax provision at federal statutory rate	$ 718	$ 982	$ 729
States, net of federal benefit, and Puerto Rico	18	63	49
Tax exempt investment income	(3)	(5)	(6)
Nondeductible executive compensation	33	19	25
Non-taxable KAH gain	(264)	0	0
Health insurance industry fee	0	268	0
Other, net	(17)	(20)	(34)
Provision for income taxes	$ 485	$ 1,307	$ 763

Effective Income Tax Rate Reconciliation, Health Insurer Fee, Amount

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Effective Income Tax Reconciliation, Non-Taxable KAH Gain

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

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