Equity Units Issued.

No definition available.

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- Definition

The amount of an increase authorized by an entity's Board of Directors to a previously authorized stock repurchase program.

+ References

No definition available.

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- Definition

Stock Repurchased and Retired During Period Average Price

+ References

No definition available.

+ Details

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

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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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- Definition

The cash inflow from the additional capital contribution to the entity.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

Number of new stock issued during the period.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Number of shares that have been repurchased and retired during the period.

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- Definition

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Capital Stock (Narrative) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions			2 Months Ended	3 Months Ended				6 Months Ended
	Jul. 12, 2018	May 01, 2018	Sep. 25, 2018	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017	Jul. 24, 2018	Dec. 07, 2017	May 12, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount				$ 6,383.2		$ 3,666.9		$ 6,383.2	$ 3,666.9
Stock Repurchased and Retired During Period, Shares								3.4	2.8
Common Stock, Dividends, Per Share, Declared				$ 0.75		$ 0.65		$ 1.50	$ 1.30
Dividends Payable, Date to be Paid				Jun. 25, 2018	Mar. 23, 2018	Jun. 23, 2017	Mar. 24, 2017
Dividends Payable, Date of Record				Jun. 08, 2018	Mar. 09, 2018	Jun. 09, 2017	Mar. 10, 2017
Increase In Stock Repurchase Program Authorization											$ 5,000.0
Proceeds from Issuance of Common Stock								$ 1,250.0	$ 0.0
Issuance of common stock under Equity Units stock purchase contracts, shares				6.0				6.0
Stock Repurchased and Retired During Period Average Price								$ 231.61	$ 180.37
Stock Repurchased and Retired During Period, Value								$ 795.0	$ 509.0
Equity Unit Purchase Agreements [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity Units Issued												25.0
Equity Units, outstanding principal amount												$ 1,250.0
Proceeds from Issuance of Common Stock		$ 1,250.0
Issuance of common stock under Equity Units stock purchase contracts, shares		6.0
Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 6,335.3
Stock Repurchased and Retired During Period, Shares	0.2
Dividends Payable, Amount Per Share										$ 0.75
Dividends Payable, Date to be Paid			Sep. 25, 2018
Dividends Payable, Date of Record			Sep. 10, 2018
Stock Repurchased and Retired During Period Average Price	$ 241.00
Stock Repurchased and Retired During Period, Value	$ 47.9
2018 to 2020 [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross								0.3
2015 to 2017 [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross								0.2