Additional Debt Securities Authorized and Available for Issuance Under Note Program

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- Definition

Bank Note Maximum Issuable Amount

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- Definition

Coupon Rate To Settle Notes

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No definition available.

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- Definition

Debt Issuance

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- Definition

Floating Rate Senior Note

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No definition available.

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- Definition

Issuance of Euro Medium Term Notes Original Maturities

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- Definition

Original Maturity of Bank Note Minimum

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- Definition

Senior Notes Available For Future Issuance.

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No definition available.

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- Definition

Senior Notes Issued

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No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Topic 942

-SubTopic 210

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-Name Regulation S-X (SX)

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-Section 03

-Paragraph 16

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Long-Term Debt - Additional Information (Detail) (USD $)	12 Months Ended	0 Months Ended
	Dec. 31, 2014	Nov. 13, 2013	Feb. 01, 2014	Nov. 26, 2014	Nov. 24, 2014	Feb. 12, 2015	Jun. 30, 2014
Debt Instrument [Line Items]
Bank note, maximum issuable amount	$ 20,000,000,000key_BankNoteMaximumIssuableAmount
Senior notes available for future issuance	17,500,000,000
Additional debt securities authorized and available for issuance under note program							4,000,000,000
Scenario, Forecast [Member]
Debt Instrument [Line Items]
Senior notes available for future issuance						16,500,000,000
Senior Notes [Member]
Debt Instrument [Line Items]
Original maturity of bank note	7 days
Subordinated Notes [Member]
Debt Instrument [Line Items]
Original maturity of bank note	5 years
Medium-Term Notes [Member]
Debt Instrument [Line Items]
Issuance of euro medium-term notes original maturities	Nine months or more
Issuance of medium-term notes		750,000,000
Additional debt securities authorized and available for issuance under note program	4,000,000,000
Coupon rate of medium-term notes		2.30%
1.65% Senior Notes Due February 1, 2018 [Member]
Debt Instrument [Line Items]
Issuance of senior bank notes			1,000,000,000
Debt instrument maturity date			Feb. 01, 2018
Debt instrument interest rate			1.65%
1.10% Senior Notes Due November 25, 2016 [Member]
Debt Instrument [Line Items]
Debt instrument maturity date				Nov. 25, 2016
Debt instrument interest rate				1.10%
Issuance of senior notes				350,000,000
Issuance of floating rate senior notes				400,000,000
2.50% Senior Notes Due December 15, 2019 [Member]
Debt Instrument [Line Items]
Debt instrument maturity date					Dec. 15, 2019
Debt instrument interest rate					2.50%
Issuance of senior notes					750,000,000
2.250% Senior Notes due March 16, 2020 [Member] \| Scenario, Forecast [Member]
Debt Instrument [Line Items]
Debt instrument maturity date						Mar. 16, 2020
Debt instrument interest rate						2.25%
Issuance of senior notes						$ 1,000,000,000