Income Taxes - Reconciliation of income taxes at the statutory rate to the provision for income taxes (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Earnings from continuing operations before income taxes (“EBT”)	$ 1,073	$ 1,123	$ 1,335
Income taxes at statutory rate	225	236	280
Effect of employee stock ownership plan dividend paid deduction	(5)	(8)	(16)
Effect of tax exempt interest	(5)	(6)	(8)
Effect of adjustments to prior year taxes	(5)	(3)	(1)
Effect of stock-based compensation	(2)	(5)	(13)
Effect of change in valuation allowance (excluding change in tax rate)	(2)	(9)	(4)
Effect of dividends received deduction	(2)	(2)	(2)
Effect of nondeductible expenses	11	8	8
Effect of foreign operations	6	7	0
Effect of other income tax reconciliation	0	7	10
Provision for income taxes as shown in the Statement of Earnings	$ 221	$ 225	$ 254
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income taxes at statutory rate as a percentage of EBT	21.00%	21.00%	21.00%
Effect of employee stock ownership plan dividend paid deduction as a percentage of EBT	(1.00%)	(1.00%)	(1.00%)
Effect of tax exempt interest as a percentage of EBT	(1.00%)	(1.00%)	(1.00%)
Effect of prior year income taxes as a percentage of EBT	0.00%	0.00%	0.00%
Effect of stock-based compensation as a percentage of EBT	0.00%	0.00%	(1.00%)
Effect of change in valuation allowance (excluding change in tax rate) as a percentage of EBT	0.00%	(1.00%)	0.00%
Effect of dividend received deduction as a percentage of EBT	0.00%	0.00%	0.00%
Effect of nondeductible expenses as a percentage of EBT	1.00%	1.00%	1.00%
Effect of foreign operations as a percentage of EBT	1.00%	1.00%	0.00%
Effect of other income tax reconciliation as a percentage of EBT	0.00%	0.00%	0.00%
Provision for income taxes as shown in the Statement of Earnings as a percentage of EBT	21.00%	20.00%	19.00%

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

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage 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 changes in the valuation allowance for deferred tax assets.

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