SCHEDULE I - PARENT COMPANY FINANCIAL INFORMATION (Condensed Statements of Comprehensive Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Condensed Financial Statements, Captions [Line Items]
Net income attributable to Humana	$ 2,933	$ 3,367	$ 2,707
Other comprehensive income (loss):
Change in gross unrealized investment (losses) gains	(356)	393	450
Effect of income taxes	81	(89)	(105)
Total change in unrealized investment (losses) gains, net of tax	(275)	304	345
Reclassification adjustment for net realized gains included in investment income	(103)	(90)	(34)
Effect of income taxes	23	20	8
Total reclassification adjustment, net of tax	(80)	(70)	(26)
Other comprehensive (loss) income, net of tax	(355)	234	319
Comprehensive income (loss) attributable to our equity method investment in Kindred at Home	6	1	(4)
Comprehensive income	2,584	3,602	3,022
Parent Company
Condensed Financial Statements, Captions [Line Items]
Net income attributable to Humana	2,933	3,367	2,707
Other comprehensive income (loss):
Change in gross unrealized investment (losses) gains	(356)	393	450
Effect of income taxes	81	(89)	(105)
Total change in unrealized investment (losses) gains, net of tax	(275)	304	345
Reclassification adjustment for net realized gains included in investment income	(103)	(90)	(34)
Effect of income taxes	23	20	8
Total reclassification adjustment, net of tax	(80)	(70)	(26)
Other comprehensive (loss) income, net of tax	(355)	234	319
Comprehensive income (loss) attributable to our equity method investment in Kindred at Home	6	1	(4)
Comprehensive income	$ 2,584	$ 3,602	$ 3,022