XML 65 R165.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Business Segment Reporting - Narrative (Details) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 USD ($) Segment | Dec. 31, 2019 USD ($) Branch industry_sector | Dec. 31, 2018 USD ($) Segment | Dec. 31, 2017 USD ($)
Segment Reporting Information [Line Items] |  |  |  |
Number of operating segments | Segment | 2 |  | 2 |
Goodwill |  | $ 2,664 | $ 2,516 | $ 2,538
Federal income tax rate |  | 21.00% | 21.00% | 35.00%
State income tax rate |  | 2.70% |  | 2.20%
Consumer Bank [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Goodwill | $ 1,600 | $ 1,752 | $ 2,102 | $ 2,124
Number of state branch network | Branch |  | 15 |  |
Commercial Bank [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Goodwill | $ 912 | $ 912 | $ 414 | $ 414
Number of business units | industry_sector |  | 7 |  |

X
- Definition This represents the blended state income tax rate (net of the federal income tax benefit) being applied to allocate income taxes. + References No definition available. + Details
Name: | key_BlendedStateIncomeTaxRate
Namespace Prefix: | key_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of industrial sectors. + References No definition available. + Details
Name: | key_NumberOfIndustrialSectors
Namespace Prefix: | key_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of state branch network. + References No definition available. + Details
Name: | key_NumberOfStateBranchNetwork
Namespace Prefix: | key_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
Name: | us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266 + Details
Name: | us-gaap_Goodwill
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
Name: | us-gaap_NumberOfOperatingSegments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
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: | 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: |