Loans and Leases - Summary of Financial Effects of Troubled Debt Restructurings (Details) - Commercial Real Estate $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021 USD ($) Investment	Sep. 30, 2022 USD ($) Investment	Sep. 30, 2021 USD ($) Investment
Financing Receivable Modifications [Line Items]
Number of loans classified as a non-accrual TDRs \| Investment		2	2	2
Pre-Modification Recorded Investment		$ 4	$ 22	$ 4
Post-Modification Recorded Investment		$ 4	$ 19	$ 4
Weighted Average Interest Rate, Pre-Modification	0.00%	6.00%	6.00%	6.00%
Weighted Average Interest Rate, Post-Modification	0.00%	3.55%	4.02%	3.55%
Trouble debt restructuring, charge-off amount			$ 3

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Weighted Average Interest Rate Pre Modification

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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