Business Acquisition, Equity Interest Issued or Issuable, Cash Paid Upon Conversion of Acquiree Stock

No definition available.

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- Definition

Business Acquisition, Equity Interest Issued or Issuable, Option to Purchase Stock, Fair Value

+ References

No definition available.

+ Details

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- Definition

Business Acquisition, Equity Interest Issued or Issuable, Shares Available for Issuance Upon Conversion Acquiree Stock

+ References

No definition available.

+ Details

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- Definition

Business Acquisition, Equity Interest Issued or Issuable, Value Assigned, Per Share

+ References

No definition available.

+ Details

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- Definition

Business Combination, Number of Branches Acquired

+ References

No definition available.

+ Details

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- Definition

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Maximum Period for Change in Fair Value Estimate

+ References

No definition available.

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-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

+ Details

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Period Type:	duration

- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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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.

+ Details

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the best estimate at the acquisition date of the contractual cash flows not expected to be collected, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

+ Details

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of the receivables acquired, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

+ Details

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

+ Details

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- Definition

Fair value at acquisition-date of the assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interests issued by the acquirer, including but not limited to, instruments or interests issued or issuable in consideration for the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

+ Details

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

+ Details

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- Details

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Business Combination - Narrative (Details)		3 Months Ended	9 Months Ended
Business Combination - Narrative (Details)	Aug. 01, 2016 USD ($) Branch $ / shares shares	Sep. 30, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jul. 29, 2016 $ / shares
Business Acquisition [Line Items]
Number of branches acquired \| Branch	390
Goodwill acquired			$ 1,420,000,000
Merger and acquisition integration costs		$ 207,000,000
First Niagara Bank, N.A. [Member]
Business Acquisition [Line Items]
Total consideration paid	$ 3,992,000,000
Maximum period for change in fair value estimate			1 year
Intangible assets acquired	388,000,000
Goodwill acquired	1,420,000,000
Merger and acquisition integration costs			$ 43,000,000
Key Community Bank [Member]
Business Acquisition [Line Items]
Goodwill acquired			1,136,000,000
Key Community Bank [Member] \| First Niagara Bank, N.A. [Member]
Business Acquisition [Line Items]
Goodwill acquired	1,100,000,000
Key Corporate Bank [Member]
Business Acquisition [Line Items]
Goodwill acquired			$ 284,000,000
Key Corporate Bank [Member] \| First Niagara Bank, N.A. [Member]
Business Acquisition [Line Items]
Goodwill acquired	$ 284,000,000
Core Deposits [Member] \| First Niagara Bank, N.A. [Member]
Business Acquisition [Line Items]
Weighted average useful life			10 years
Intangible assets acquired		$ 356,000,000	$ 356,000,000
Commercial Credit Card [Member] \| First Niagara Bank, N.A. [Member]
Business Acquisition [Line Items]
Weighted average useful life			6 years
Consumer Credit Card [Member] \| First Niagara Bank, N.A. [Member]
Business Acquisition [Line Items]
Weighted average useful life			9 years
Common Stock [Member] \| First Niagara Bank, N.A. [Member]
Business Acquisition [Line Items]
Shares available for issuance upon conversion of acquiree stock \| shares	0.680
Cash paid upon conversion of acquiree stock	$ 2.30
Shares received by acquiree, per share \| $ / shares	$ 10.26
Closing price of acquiree stock, per share \| $ / shares				$ 11.70
Number of shares received by acquiree \| shares	240,000,000
Fair value of acquiree options to purchase common stock	$ 26,000,000
PCI [Member] \| First Niagara Bank, N.A. [Member]
Business Acquisition [Line Items]
Contractually required payments receivable	23,100,000,000
Fair value of acquired receivables	22,500,000,000
Estimated cash flows not expected to be collected	$ 466,000,000