Fair Value of financial instruments- Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Letter Of Credit
Commitments and contingencies
Fair Value Disclosure Off balance Sheet Risks Face Amount Asset	$ 24	$ 31
Commitments to extend credit
Commitments and contingencies
Fair Value Disclosure Off balance Sheet Risks Face Amount Asset	$ 10,300	$ 9,500

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