Investments - Low Income Housing Tax Credit Investments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Low income housing tax credit investments	$ 7	$ 6	$ 6
Amount of amortization reported in income tax expense	6	5	$ 4
Total carrying value of LIHTC investments	68	54
Liability for unfunded commitments	$ 30	$ 19