Loans and Leases - Summary of Financial Effects of Troubled Debt Restructurings (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) Investment	Mar. 31, 2021 USD ($) Investment
Commercial Real Estate
Financing Receivable Modifications [Line Items]
Number of loans classified as a non-accrual TDRs \| Investment	1
Pre-Modification Recorded Investment	$ 22
Post-Modification Recorded Investment	$ 19
Weighted Average Interest Rate, Pre-Modification	6.00%
Weighted Average Interest Rate, Post-Modification	4.00%
Trouble debt restructuring, charge-off amount	$ 3
Multi-Family
Financing Receivable Modifications [Line Items]
Number of loans classified as a non-accrual TDRs \| Investment		1
Pre-Modification Recorded Investment		$ 8
Post-Modification Recorded Investment		$ 8
Weighted Average Interest Rate, Pre-Modification		3.13%
Weighted Average Interest Rate, Post-Modification		3.25%

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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 http://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 http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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