Derivative Financial Instruments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Derivative [Line Items]
Amount of gain (loss) on de-designated cash flow hedges, net of tax, to be reclassified during the next 12 months	$ 10		$ 10
Amount of gain (loss), net of tax, to be reclassified during the next 12 months	(11)		(11)
Right to reclaim cash	133		133		$ 66
Right to reclaim cash, cash collateral	27		27		28
Right to reclaim cash, maintenance margin	106		106		38
Obligation to return cash	152		152		12
De-designated Cash Flow Hedges
Derivative [Line Items]
Unrealized gains (losses) on derivatives			41
Gains (losses) on cash flow hedging relationships reclassified into interest income	2		6
Gains (losses) on fair value hedging relationships recorded in interest income	2		3
Cash Flow Hedges
Derivative [Line Items]
Unrealized gains (losses) on derivatives			(92)		$ 20
Gains (losses) on cash flow hedging relationships reclassified into interest income	$ 2	$ (1)	$ 12	$ (3)
Gains (losses) on fair value hedging relationships recorded in interest income		$ (1)		$ (3)