Represents the amount of cash paid to acquire remaining interest.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

The term of the discounted forecasted cash flow used to estimate the fair value of the redeemable noncontrolling interest.

+ References

No definition available.

+ Details

Name:	cat_DiscountedForecastedCashFlowTerm
Namespace Prefix:	cat_
Data Type:	us-types:durationStringItemType
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Period Type:	duration

- Definition

The increase or decrease in the carrying value of redeemable noncontrolling interest due to the subsidiary's comprehensive gain or loss during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	cat_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the increase or decrease in the estimated redemption value of redeemable noncontrolling interest due to foreign exchange fluctuation during the period.

+ References

No definition available.

+ Details

Name:	cat_TemporaryEquityIncreaseDecreaseInEstimatedRedemptionValueDueToForeignExchangeFlutuation
Namespace Prefix:	cat_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The increase or decrease in retained earnings due to adjustments made in the carrying value of redeemable noncontrolling interest during the period as a result of a decrease or increase in the estimated redemption value.

+ References

No definition available.

+ Details

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Namespace Prefix:	cat_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The increase or decrease in retained earnings due to adjustment to increase or decrease the carrying value of redeemable noncontrolling interest to the redemption value.

+ References

No definition available.

+ Details

Name:	cat_TemporaryEquityIncreaseDecreaseInRetainedEarningsAdjustmentToDecreaseIncreaseCarryingValueOfRedeemableNoncontrollingInterestToRedemptionValue
Namespace Prefix:	cat_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_RedeemableNoncontrollingInterestAbstract
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Data Type:	xbrli:stringItemType
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- Definition

The aggregate amount to be paid by the entity upon redemption of the security that is classified as temporary equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 02

-Paragraph 28

-Subparagraph b

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 00-19

-Paragraph 12

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.27(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Redeemable Noncontrolling Interest - Caterpillar Japan Ltd. (Details) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012 USD ($)	Mar. 31, 2011 USD ($)	Apr. 02, 2012 USD ($)	Apr. 02, 2012 JPY (¥)	Dec. 31, 2011 USD ($)	Aug. 01, 2008
Redeemable Noncontrolling Interest - Caterpillar Japan Ltd.
Cat Japan, consolidated subsidiary, Caterpillar majority percentage ownership	33.00%					67.00%
Cat Japan, consolidated subsidiary, MHI minority percentage ownership						33.00%
Cash paid for acquiring remaining equity interest			$ 444	¥ 36,500
Increase or decrease in profit employed in the business, due to adjustments to carrying value of redeemable noncontrolling interest		8
Term of discounted forecasted cash flow (in years)	5 years
Increase or Decrease in carrying value of redeemable noncontrolling interest due to subsidiary's comprehensive income or loss	10	23
Increase or decrease in profit employed in the business due to adjusting the carrying value of redeemable noncontrolling interest to the redemption value	(10)	(23)
Decrease in estimated redemption value due to foreign exchage fluctuation	18
Redeemable noncontrolling interest, after exchange rates impact	$ 455				$ 473