Liability for Pension and Other Retirement Benefits (Details 6)	12 Months Ended
Mar. 31, 2011	Mar. 31, 2010	Mar. 31, 2009
Domestic plans [Member]
Weighted-average assumptions for net periodic benefit cost
Discount rate	2.00%	2.00%	2.00%
Assumed rate of increase in future compensation levels (Point-based benefit system)	3.80%	3.90%	3.90%
Assumed rate of increase in future compensation levels	2.60%	2.40%	2.00%
Expected long-term rate of return on plan assets	1.90%	1.90%	1.90%
Foreign plans [Member]
Weighted-average assumptions for net periodic benefit cost
Discount rate	6.00%	6.90%	6.70%
Assumed rate of increase in future compensation levels (Point-based benefit system)	0.00%	0.00%	0.00%
Assumed rate of increase in future compensation levels	4.40%	4.10%	4.40%
Expected long-term rate of return on plan assets	7.20%	7.60%	7.50%

Defined benefit plan assumptions used calculating net periodic benefit cost rate of compensation increase point based Benefit system.

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- Definition

The interest rate used to adjust for the time value of money.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph j

+ Details

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 264

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph j

+ Details

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph j

+ Details

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- Details

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