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Regulatory Matters - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2025 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
Short-term investments held for discharge of obligations | $ 4,900
KeyBank (consolidated) |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
Dividends paid by non banking subsidiaries | 1,400
Capacity to pay dividends | $ 783

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