Reclassifications Out of Accumulated Other Comprehensive Loss - Reclassifications of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax benefit		$ 176	$ 210	$ 77
Net income		650	596	511
Interest expense		696	$ 400	$ 608
Reclassifications, net of tax	[1]	1
Past service liability
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax	[1],[2]	0
Actuarial losses
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax	[1],[2]	(2)
Amortization of defined benefit pension
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax	[1]	(2)
Income tax benefit	[1]	0
Reclassifications, net of tax	[1]	(2)
Reclassification out of Accumulated Other Comprehensive Income (loss) | Unrealized gains on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gain on securities	[1]	0
Income tax benefit	[1]	0
Net income	[1]	0
Reclassification out of Accumulated Other Comprehensive Income (loss) | Unrealized gains on cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax benefit	[1]	(1)
Net income	[1]	3
Interest expense	[1]	$ 4

[1] Amounts in parentheses indicate expense items.

[2] See Note 17, “Employee Benefits,” for additional information.