Excess Of Estimated Fair Value Over Carrying Value As Percentage Of Carrying Value

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- Definition

Goodwill Expected To Be Deductible For Tax Purposes

+ References

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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- Definition

Amount of accumulated impairment loss for 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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- 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.

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Goodwill and Other Intangible Assets - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Oct. 02, 2017	Sep. 30, 2017	Jul. 01, 2017	Jun. 30, 2017	Dec. 31, 2016
Goodwill [Line Items]
Expected deductible goodwill for tax purpose	$ 540,000,000
Key Merchant Services, LLC [Member]
Goodwill [Line Items]
Intangible assets acquired				$ 85,000,000		$ 95,000,000
HelloWallet Holdings, LLC [Member]
Goodwill [Line Items]
Intangible assets acquired					$ 12,000,000
Cain Brothers & Company, LLC. [Member]
Goodwill [Line Items]
Intangible assets acquired			$ 30,000,000
Key Community Bank Unit [Member]
Goodwill [Line Items]
Estimated fair value of the Community Bank unit greater than certain percent of carrying value	48.00%
Accumulated impairment loss	$ 0	$ 0					$ 0
Key Corporate Bank [Member]
Goodwill [Line Items]
Estimated fair value of the Community Bank unit greater than certain percent of carrying value	39.00%
Accumulated impairment loss	$ 0	$ 0					$ 0
Customer Relationships [Member] \| Key Merchant Services, LLC [Member]
Goodwill [Line Items]
Useful life of intangible assets	10 years
Customer Relationships [Member] \| Cain Brothers & Company, LLC. [Member]
Goodwill [Line Items]
Useful life of intangible assets	8 years
Proprietary Software [Member] \| HelloWallet Holdings, LLC [Member]
Goodwill [Line Items]
Useful life of intangible assets	3 years
Trade Names [Member] \| Cain Brothers & Company, LLC. [Member]
Goodwill [Line Items]
Useful life of intangible assets	3 years