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Income Taxes (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020
Income Tax Contingency [Line Items] |  |  |
Total income tax expense (benefit), rate | 19.40% | 13.40% |
Combined federal and state statutory tax rate | 23.70% |  |
Valuation allowance | $ 0 |  | $ 0
Accrued Liabilities and Other Liabilities |  |  |
Income Tax Contingency [Line Items] |  |  |
Net deferred tax liability | 11,000,000 |  | $ 100,000,000
Key Corp |  |  |
Income Tax Contingency [Line Items] |  |  |
Unrecognized tax benefits | 56,000,000 |  |
First Niagara Bank, N.A. |  |  |
Income Tax Contingency [Line Items] |  |  |
Allocated bad debt deductions | $ 92,000,000 |  |

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- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=120406818&loc=d3e31931-109318 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=120406818&loc=d3e31917-109318 + Details
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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