Restrictions on Cash and Cash Equivalents	3 Months Ended
Mar. 31, 2022
Cash and Cash Equivalents [Abstract]
Restrictions on Cash and Cash Equivalents	Restrictions on Cash and Cash EquivalentsCash collateral is posted by the Corporation with counterparties to secure derivatives and other contracts, which is included in "interest-bearing deposits with other banks" on the consolidated balance sheets. The amounts of such collateral as of March 31, 2022 and December 31, 2021 were $64.5 million and $202.8 million, respectively.

Tabular disclosure of cash and cash equivalents restricted as to withdrawal or usage.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(1)(a))
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.7-03(a)(2))
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-Name Accounting Standards Codification
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