This element represents the effect of any changes in a parent's ownership interest in a subsidiary except net income (loss), comprehensive income (loss), dividends in and contributions to the subsidiaries.

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Balance Type:	credit
Period Type:	duration

- Definition

Increase in noncontrolling interests due to investments to subsidiaries from noncontrolling interest holders .

+ Details

Name:	kub_IncreaseInNoncontrollingInterestRelatedToContribution
Namespace Prefix:	kub
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Net value of common stock that was acquired or reissued during the period. Recorded using the cost method.

+ Details

Name:	kub_TreasuryStockValueNetAcquiredReissued
Namespace Prefix:	kub
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Common stock cash dividend declared by an entity during the period. This element includes paid and unpaid dividends declared during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions to noncontrolling interest holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(2)

+ Details

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents Other Comprehensive Income (Loss), Net of Tax, for the period. Includes deferred gains (losses) on qualifying hedges, unrealized holding gains (losses) on available-for-sale securities, minimum pension liability, and cumulative translation adjustment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 22, 23, 24, 25

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 31
-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A1, A4, A5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 5
-Subparagraph b

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 29

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 AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(1)

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Total of Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity including portions attributable to both the parent and noncontrolling interests (previously referred to as minority interest), if any. The entity including portions attributable to the parent and noncontrolling interests is sometimes referred to as the economic entity. This excludes temporary equity and is sometimes called permanent equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 25

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 26

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A3
-Appendix A

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Consolidated Statements of Changes in Equity (JPY ¥) In Millions	Common Stock [Member]	Capital Surplus [Member]	Legal Reserve [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock at Cost [Member]	Non-Controlling Interests [Member]	Total
Balance at Mar. 31, 2008	¥ 84,070	¥ 93,150	¥ 19,539	¥ 423,927	¥ 31,177	¥ (3,766)	¥ 43,230	¥ 691,327
Net income				48,064			6,671	54,735
Other comprehensive income (loss)					(93,361)		(10,211)	(103,572)
Cash dividends paid to Kubota Corporation shareholders				(19,193)				(19,193)
Cash dividends paid to noncontrolling interests							(767)	(767)
Purchases and sales of treasury stock				(7)		(5,316)		(5,323)
Increase in noncontrolling interests related to contribution							14	14
Changes in ownership interests in subsidiaries							(978)	(978)
Balance at Mar. 31, 2009	84,070	93,150	19,539	452,791	(62,184)	(9,082)	37,959	616,243
Net income				42,326			5,582	47,908
Other comprehensive income (loss)					28,429		1,946	30,375
Cash dividends paid to Kubota Corporation shareholders				(17,814)				(17,814)
Cash dividends paid to noncontrolling interests							(489)	(489)
Purchases and sales of treasury stock						(183)		(183)
Increase in noncontrolling interests related to contribution							2,109	2,109
Changes in ownership interests in subsidiaries		(3,909)			(736)		(1,885)	(6,530)
Balance at Mar. 31, 2010	84,070	89,241	19,539	477,303	(34,491)	(9,265)	45,222	671,619
Net income				54,822			6,286	61,108
Other comprehensive income (loss)					(30,710)		(3,073)	(33,783)
Cash dividends paid to Kubota Corporation shareholders				(15,267)				(15,267)
Cash dividends paid to noncontrolling interests							(307)	(307)
Purchases and sales of treasury stock		1				(76)		(75)
Increase in noncontrolling interests related to contribution		(5)					400	395
Changes in ownership interests in subsidiaries		(97)			(180)		(2,052)	(2,329)
Balance at Mar. 31, 2011	¥ 84,070	¥ 89,140	¥ 19,539	¥ 516,858	¥ (65,381)	¥ (9,341)	¥ 46,476	¥ 681,361