Income Taxes - Reconciliation of income taxes at the statutory rate to the provision for income taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Earnings (loss) from continuing operations before income taxes (“EBT”)	$ 288	$ 140	$ 623	$ (45)
Income taxes at statutory rate	61	30	131	(9)
Effect of stock-based compensation	(8)	0	(10)	(3)
Effect of ESOP dividend paid deduction	(8)	0	(8)	0
Effect of tax exempt interest	(2)	(3)	(4)	(5)
Effect of dividends received deduction	(1)	0	(1)	(1)
Effect of foreign operations	(1)	0	(2)	1
Effect of nondeductible expenses	2	1	4	2
Effect of change in valuation allowance	3	9	3	11
Effect of other income	2	0	3	0
Provision for income taxes as shown on the Statement of Earnings	$ 48	$ 37	$ 116	$ (4)
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income taxes at statutory rate as a percentage of EBT	21.00%	21.00%	21.00%	21.00%
Effect of stock-based compensation as a percentage of EBT	(3.00%)	0.00%	(2.00%)	7.00%
Effect of ESOP dividend paid deduction as a percentage of EBT	(3.00%)	0.00%	(1.00%)	0.00%
Effect of tax exempt interest as a percentage of EBT	(1.00%)	(2.00%)	(1.00%)	11.00%
Effect of dividends received deduction as a percentage of EBT	0.00%	0.00%	0.00%	2.00%
Effect of foreign operations as a percentage of EBT	0.00%	0.00%	0.00%	(2.00%)
Effect of nondeductible expenses as a percentage of EBT	1.00%	1.00%	1.00%	(4.00%)
Effect of change in valuation allowance as a percentage of EBT	1.00%	6.00%	0.00%	(25.00%)
Effect of other income tax reconciliation as a percentage of EBT	1.00%	0.00%	1.00%	(1.00%)
Provision for income taxes as shown on the Statement of Earnings as a percentage of EBT	17.00%	26.00%	19.00%	9.00%

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

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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