Subsequent Event	12 Months Ended
Dec. 31, 2022
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventAs of December 31, 2022, the Corporation intended to sell certain available-for-sale debt securities that were in an unrealized loss position. The securities were written down to their fair value of $2.1 billion with a $213.0 million loss recognized in Investment Security Gains (Losses), net on the consolidated statements of income. In January 2023, the securities were subsequently sold resulting in an incremental $6.9 million gain upon sale as compared to the fair value recorded on the consolidated balance sheets at December 31, 2022.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI https://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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