Shareholders' Equity (Schedule of Effects of Changes in Ownership Interests in Subsidiaries) (Details) (JPY ¥) In Millions	12 Months Ended
Mar. 31, 2011	Mar. 31, 2010	Mar. 31, 2009
Shareholders' Equity
Net income attributable to Kubota Corporation	¥ 54,822	¥ 42,326	¥ 48,064
Increase in capital surplus for purchases of noncontrolling interests	425	125
Decrease in capital surplus for purchases of noncontrolling interests	(726)	(3,828)
Increase in capital surplus for changes in ownership interests in subsidiaries from other transactions	199
Decrease in capital surplus for changes in ownership interests in subsidiaries from other transactions		(206)
Net transfers to the noncontrolling interests	(102)	(3,909)
Change from net income attributable to Kubota Corporation and transfer to noncontrolling interests	¥ 54,720	¥ 38,417

Represents other transactions resulting in a increase in total (consolidated) equity attributable to the parent.

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- Definition

This element represents the total net income attributable to the parent for the period and the effect of net changes during the period impacting the parent's ownership interest in a subsidiary as it relates to the total (consolidated) equity attributable to the parent. The changes to the parent's ownership interest in a subsidiary represented by this element did not result in a deconsolidation of the subsidiary from the consolidated financial statements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph d

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A7
-Appendix A

+ Details

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- Definition

Represents a (non-cash) issuance of additional equity interests to the parent by a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The additional equity interest represented by this element increases the parent's controlling interest in the subsidiary.

+ References

+ Details

Name:	us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestChangesAdditionalInterestIssuedToParent
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Data Type:	xbrli:monetaryItemType
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- Definition

This element represents the total net changes during the period impacting the parent's ownership interest in a subsidiary as it relates to the total (consolidated) equity attributable to the parent. The changes to the parent's ownership interest in a subsidiary represented by this element did not arise in a deconsolidation of the subsidiary from the consolidated financial statements.

+ References

+ Details

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- Definition

Represents the purchase by the parent of an additional equity interest in a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The purchase of the additional equity interest represented by this element increases the parent's controlling interest in the subsidiary.

+ References

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
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- Definition

Represents a sale by the parent of a portion of its equity interest in a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The sale of the equity interest represented by this element does not result in a loss of control by the parent.

+ References

+ Details

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- Definition

The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 19
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph d

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A7
-Appendix A

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph a

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 20
-Article 9

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 10, 15

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 87-21

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28, 29, 30

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- Details

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