XML 187 R166.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Business Segment Reporting - Financial Information of Business Groups (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 USD ($) employee | Dec. 31, 2018 USD ($) employee | Dec. 31, 2017 USD ($) employee
Segment Reporting Information [Line Items] |  |  |
Net interest income (TE) | $ 3,941 | $ 3,940 | $ 3,830
Noninterest income | 2,459 | 2,515 | 2,478
Total revenue (TE) | 6,400 | 6,455 | 6,308
Provision for credit losses | 445 | 246 | 229
Depreciation and amortization expense | 374 | 400 | 384
Other noninterest expense | 3,527 | 3,575 | 3,714
Income (loss) from continuing operations before income taxes (TE) | 2,054 | 2,234 | 1,981
Allocated income taxes (benefit) and TE adjustments | 346 | 375 | 690
INCOME (LOSS) FROM CONTINUING OPERATIONS | 1,708 | 1,859 | 1,291
Income (loss) from discontinued operations, net of taxes | 9 | 7 | 7
NET INCOME (LOSS) | 1,717 | 1,866 | 1,298
Less: Net income (loss) attributable to noncontrolling interests | 0 | 0 | 2
NET INCOME (LOSS) ATTRIBUTABLE TO KEY | 1,717 | 1,866 | 1,296
AVERAGE BALANCES |  |  |
Loans and leases | 91,511 | 88,338 | 86,365
Total assets | 143,179 | 136,812 | 133,719
Deposits | 110,030 | 105,051 | 102,946
OTHER FINANCIAL DATA |  |  |
Expenditures for additions to long-lived assets | 245 | 48 | 267
Net loan charge-offs | $ 424 | $ 234 | $ 208
Return on average allocated equity, continuing operations (as a percentage) | 10.27% | 12.29% | 8.47%
Return on average allocated equity (as a percentage) | 10.32% | 12.33% | 8.51%
Average full-time equivalent employees | employee | 17,045 | 18,180 | 18,415
Provision for credit loss, net of tax, related to previously disclosed fraud incident | $ 139 |  |
Operating Segments [Member] | Consumer Bank [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (TE) | 2,366 | $ 2,306 | $ 2,133
Noninterest income | 922 | 915 | 976
Total revenue (TE) | 3,288 | 3,221 | 3,109
Provision for credit losses | 188 | 147 | 145
Depreciation and amortization expense | 97 | 103 | 108
Other noninterest expense | 2,078 | 2,143 | 2,167
Income (loss) from continuing operations before income taxes (TE) | 925 | 828 | 689
Allocated income taxes (benefit) and TE adjustments | 219 | 196 | 255
INCOME (LOSS) FROM CONTINUING OPERATIONS | 706 | 632 | 434
Income (loss) from discontinued operations, net of taxes | 0 | 0 | 0
NET INCOME (LOSS) | 706 | 632 | 434
Less: Net income (loss) attributable to noncontrolling interests | 0 | 0 | 0
NET INCOME (LOSS) ATTRIBUTABLE TO KEY | 706 | 632 | 434
AVERAGE BALANCES |  |  |
Loans and leases | 32,536 | 31,307 | 32,092
Total assets | 36,096 | 34,523 | 35,360
Deposits | 72,544 | 68,821 | 66,711
OTHER FINANCIAL DATA |  |  |
Expenditures for additions to long-lived assets | 150 | (38) | 90
Net loan charge-offs | $ 157 | $ 149 | $ 152
Return on average allocated equity, continuing operations (as a percentage) | 21.30% | 19.24% | 13.19%
Return on average allocated equity (as a percentage) | 21.30% | 19.24% | 13.19%
Average full-time equivalent employees | employee | 9,292 | 9,957 | 9,990
Operating Segments [Member] | Commercial Bank [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (TE) | $ 1,621 | $ 1,657 | $ 1,708
Noninterest income | 1,390 | 1,328 | 1,272
Total revenue (TE) | 3,011 | 2,985 | 2,980
Provision for credit losses | 118 | 102 | 84
Depreciation and amortization expense | 135 | 139 | 103
Other noninterest expense | 1,388 | 1,430 | 1,393
Income (loss) from continuing operations before income taxes (TE) | 1,370 | 1,314 | 1,400
Allocated income taxes (benefit) and TE adjustments | 223 | 207 | 373
INCOME (LOSS) FROM CONTINUING OPERATIONS | 1,147 | 1,107 | 1,027
Income (loss) from discontinued operations, net of taxes | 0 | 0 | 0
NET INCOME (LOSS) | 1,147 | 1,107 | 1,027
Less: Net income (loss) attributable to noncontrolling interests | 0 | 0 | 0
NET INCOME (LOSS) ATTRIBUTABLE TO KEY | 1,147 | 1,107 | 1,027
AVERAGE BALANCES |  |  |
Loans and leases | 57,988 | 55,828 | 52,783
Total assets | 66,122 | 63,684 | 59,956
Deposits | 36,212 | 33,675 | 33,781
OTHER FINANCIAL DATA |  |  |
Expenditures for additions to long-lived assets | (8) | (17) | 69
Net loan charge-offs | $ 128 | $ 85 | $ 55
Return on average allocated equity, continuing operations (as a percentage) | 24.99% | 24.94% | 23.91%
Return on average allocated equity (as a percentage) | 24.99% | 24.94% | 23.91%
Average full-time equivalent employees | employee | 2,232 | 2,449 | 2,331
Corporate And Reconciling Items [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Net interest income (TE) | $ (46) | $ (23) | $ (11)
Noninterest income | 147 | 272 | 230
Total revenue (TE) | 101 | 249 | 219
Provision for credit losses | 139 | (3) | 0
Depreciation and amortization expense | 142 | 158 | 173
Other noninterest expense | 61 | 2 | 154
Income (loss) from continuing operations before income taxes (TE) | (241) | 92 | (108)
Allocated income taxes (benefit) and TE adjustments | (96) | (28) | 62
INCOME (LOSS) FROM CONTINUING OPERATIONS | (145) | 120 | (170)
Income (loss) from discontinued operations, net of taxes | 9 | 7 | 7
NET INCOME (LOSS) | (136) | 127 | (163)
Less: Net income (loss) attributable to noncontrolling interests | 0 | 0 | 2
NET INCOME (LOSS) ATTRIBUTABLE TO KEY | (136) | 127 | (165)
AVERAGE BALANCES |  |  |
Loans and leases | 987 | 1,203 | 1,490
Total assets | 40,961 | 38,605 | 38,403
Deposits | 1,274 | 2,555 | 2,454
OTHER FINANCIAL DATA |  |  |
Expenditures for additions to long-lived assets | 103 | 103 | 108
Net loan charge-offs | $ 139 | $ 0 | $ 1
Return on average allocated equity, continuing operations (as a percentage) | (1.66%) | 1.62% | (2.25%)
Return on average allocated equity (as a percentage) | (1.56%) | 1.71% | (2.16%)
Average full-time equivalent employees | employee | 5,521 | 5,774 | 6,094
Provision for credit loss, net of tax, related to previously disclosed fraud incident | $ 106 |  |

X
- Definition Average total assets. + References No definition available. + Details
Name: | key_AverageAssets
Namespace Prefix: | key_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Average balances. + References No definition available. + Details
Name: | key_AverageBalancesAbstract
Namespace Prefix: | key_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Average deposits. + References No definition available. + Details
Name: | key_AverageDeposits
Namespace Prefix: | key_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Average loans and leases. + References No definition available. + Details
Name: | key_AverageLoansAndLeases
Namespace Prefix: | key_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Capital Expenditures Additions To Assets + References No definition available. + Details
Name: | key_CapitalExpendituresAdditionsToAssets
Namespace Prefix: | key_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing receivable allowance for credit losses lending related commitments. + References No definition available. + Details
Name: | key_FinancingReceivableAllowanceForCreditLossesLendingRelatedCommitments
Namespace Prefix: | key_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Amount Realized Loss From Fraud Incident + References No definition available. + Details
Name: | key_FinancingReceivableAmountRealizedLossFromFraudIncident
Namespace Prefix: | key_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Income Tax Expense (Benefit) and Taxable Equivalent Adjustments + References No definition available. + Details
Name: | key_IncomeTaxExpenseBenefitandTaxableEquivalentAdjustments
Namespace Prefix: | key_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Interest Income (Expense), Net, Taxable Equivalent + References No definition available. + Details
Name: | key_InterestIncomeExpenseNetTaxableEquivalent
Namespace Prefix: | key_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Loans charged off and recoveries of loans previously charged off. + References No definition available. + Details
Name: | key_LoansChargedOffAndRecoveriesOfLoansPreviouslyChargedOff
Namespace Prefix: | key_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Noninterest and Other Expense + References No definition available. + Details
Name: | key_NoninterestandOtherExpense
Namespace Prefix: | key_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Average full time equivalent employees. + References No definition available. + Details
Name: | key_NumberOfFullTimeEquivalentEmployees
Namespace Prefix: | key_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Other financial data. + References No definition available. + Details
Name: | key_OtherFinancialDataAbstract
Namespace Prefix: | key_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Return on average allocated equity. + References No definition available. + Details
Name: | key_ReturnOnAverageAllocatedEquity
Namespace Prefix: | key_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Return on average allocated equity. + References No definition available. + Details
Name: | key_ReturnOnAverageAllocatedEquityContinuingOperations
Namespace Prefix: | key_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 + Details
Name: | us-gaap_DepreciationAndAmortization
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(1)(i)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount after tax of income (loss) from continuing operations including portion attributable to the noncontrolling interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683 + Details
Name: | us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(12)) -URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 3B -URI http://asc.fasb.org/extlink&oid=109222160&loc=SL51721525-107759 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 5C -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721675-107760 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109222160&loc=d3e957-107759 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109222650&loc=d3e1361-107760 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(21)) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 3A -URI http://asc.fasb.org/extlink&oid=109222160&loc=SL51721523-107759 Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109222160&loc=d3e1012-107759 + Details
Name: | us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(22)) -URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(18)) -URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(20)) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
Name: | us-gaap_NetIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of Net Income (Loss) attributable to noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4J -URI http://asc.fasb.org/extlink&oid=116874947&loc=SL4591551-111686 + Details
Name: | us-gaap_NetIncomeLossAttributableToNoncontrollingInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13) -URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260 + Details
Name: | us-gaap_NoninterestIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4J -URI http://asc.fasb.org/extlink&oid=116874947&loc=SL4591551-111686 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3000-108585 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8933-108599 Reference 10: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4K -URI http://asc.fasb.org/extlink&oid=116874947&loc=SL4591552-111686 + Details
Name: | us-gaap_ProfitLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8933-108599 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(1)) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
Name: | us-gaap_Revenues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_SegmentReportingInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=key_ConsumerBankMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=key_CommercialBankMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ConsolidationItemsAxis=key_CorporateAndReconcilingItemsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |