Acquisition and Divestiture - Summary of Acquisition, Pro Forma Information (Details) - Peoples United Financial Inc [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Accounts Notes And Loans Receivable [Line Items]
Total revenues	$ 2,054,462	$ 6,134,400	$ 6,056,364
Net income	$ 664,820	$ 1,399,913	$ 1,769,781

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.

No definition available.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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-Name Accounting Standards Codification
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