Income Taxes - Reconciliation of income taxes at the statutory rate to the provision for income taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Earnings (loss) before income taxes (“EBT”)	$ 134	$ 177	$ (36)	$ 849
Income taxes at statutory rate	28	37	(8)	178
Effect of a sale of subsidiaries	(73)	0	(73)	0
Effect of tax exempt interest	(3)	(4)	(9)	(11)
Effect of stock-based compensation	0	(2)	(4)	(6)
Effect of dividends received deduction	(1)	(1)	(2)	(3)
Effect of prior year income taxes	(1)	(3)	(1)	(3)
Effect of employee stock ownership plan dividend paid deduction	(1)	0	(1)	(1)
Effect of change in valuation allowance	20	4	31	7
Effect of nondeductible expenses	2	2	4	6
Effect of foreign operations	(4)	0	(3)	0
Effect of other income tax reconciliation	3	1	3	4
Provision for income taxes as shown on the Statement of Earnings	$ (30)	$ 34	$ (63)	$ 171
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 sale of subsidiaries as a percentage of EBT	(54.00%)	0.00%	203.00%	0.00%
Effect of tax exempt interest as a percentage of EBT	(2.00%)	(2.00%)	25.00%	(1.00%)
Effect of stock-based compensation as a percentage of EBT	0.00%	(1.00%)	11.00%	(1.00%)
Effect of dividends received deduction as a percentage of EBT	(1.00%)	(1.00%)	6.00%	0.00%
Effect of prior year taxes as a percentage of EBT	(1.00%)	(2.00%)	3.00%	0.00%
Effect of dividends received deduction as a percentage of EBT	(1.00%)	0.00%	3.00%	0.00%
Effect of change in valuation allowance as a percentage of EBT	15.00%	2.00%	(86.00%)	1.00%
Effect of nondeductible expenses as a percentage of EBT	1.00%	1.00%	(11.00%)	1.00%
Effect of foreign operations as a percentage of EBT	(3.00%)	0.00%	8.00%	0.00%
Effect of other income tax reconciliation as a percentage of EBT	3.00%	1.00%	(8.00%)	(1.00%)
Provision for income taxes as shown on the Statement of Earnings as a percentage of EBT	(22.00%)	19.00%	175.00%	20.00%

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

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