Retirement and Benefit Plans - Retirement and Benefit Plans - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure
Increase in pension expense by lowering both the expected rate of return on the plan and the discount rate by 0.25%	$ 1
Estimated future defined benefit plan contributions	2
Estimated pension benefit payments for 2022	17
Estimated pension benefit payments for 2023	16
Estimated pension benefit payments for 2024	15
Estimated pension benefit payments for 2025	17
Estimated pension benefit payments for 2026	14
Estimated pension benefit payments for 2027 through 2031	59
Trustee fees	0
Qualified defined contribution plan
Defined Benefit Plan Disclosure
Expenses recognized for the Bancorp's defined contribution plan	108	$ 105	$ 90
Non-qualified defined contribution plan
Defined Benefit Plan Disclosure
Expenses recognized for the Bancorp's defined contribution plan	5	5	6
Deferred profit sharing
Defined Benefit Plan Disclosure
Expenses recognized for the Bancorp's defined contribution plan	$ 0	$ 0	$ 4

Defined Benefit Plan, Effect of 25 Basis Point Decrease in Expected Rate of Return and Discount Rate

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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Amount of cost for defined contribution plan.

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Fees charged annually for the professional services of a trustee, usually quoted as a percentage of the funds being managed. The fee for appointing an offshore Trustee is included in the trust price.

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