Subsequent Events (Details) (Acquisition, Bucyrus International, Inc., USD $)	0 Months Ended	1 Months Ended
Jul. 08, 2011	May 31, 2011
Acquisition \| Bucyrus International, Inc.
Subsequent Event
Purchase price of acquired entity	$ 8,800,000,000
Outstanding Shares	7,400,000,000
Common stock price (in dollars per share)	$ 92
Debt assumed	1,600,000,000
Cash acquired in acquisition	200,000,000
Additional borrowing		$ 4,500,000,000

Represents face amount or stated value of common stock per share acquired entity.

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- Definition

The debt assumed as part of the purchase price, which is included among the aggregate liabilities assumed.

+ Details

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- Definition

The amount of acquisition cost of a business combination allocated to an outstanding shares of acquired entity.

+ Details

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d

+ Details

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- Definition

The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 15, 16, 17

+ Details

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- Definition

Increase for additional borrowings on the debt instrument during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph f
-Article 4

+ 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.

+ Details

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