Government bonds and municipal bonds.

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Investment trusts hold by foreign subsidiaries.

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- Definition

Liability for Pension and Other Retirement Benefits.

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Mandatory retirement age.

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- Definition

Percentage of common stock of company included in plan assets.

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Percentage of employee benefits payable as pension.

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For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

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

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The amount of employer securities or securities of parties related to the employer that are included in plan assets.

+ References

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

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The percentage of the fair value of debt securities to the fair value of total plan assets held as of the measurement date.

+ References

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

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The percentage of the fair value of equity securities to the fair value of total plan assets held as of the measurement date.

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

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The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

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

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The percentage of the fair value of investments other than debt securities, equity securities, and real estate to the fair value of total plan assets held as of the measurement date.

+ References

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

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Liability for Pension and Other Retirement Benefits (Details Textuals)					12 Months Ended
	Mar. 31, 2011 USD ($)	Mar. 31, 2011 Level 3 [Member] Pension Plans, Defined Benefit [Member] USD ($)	Mar. 31, 2011 Level 3 [Member] Pension Plans, Defined Benefit [Member] JPY (¥)	Mar. 31, 2010 Level 3 [Member] Pension Plans, Defined Benefit [Member] JPY (¥)	Mar. 31, 2011 Pension Plans, Defined Benefit [Member] USD ($)	Mar. 31, 2010 Pension Plans, Defined Benefit [Member] JPY (¥)	Mar. 31, 2011 Pension Plans, Defined Benefit [Member] JPY (¥)	Mar. 31, 2011 Pension Plans, Defined Benefit [Member] Japanese Bonds [Member]	Mar. 31, 2011 Pension Plans, Defined Benefit [Member] Foreign Bonds [Member]	Mar. 31, 2011 Other Postretirement Benefit Plans, Defined Benefit [Member] JPY (¥)
Liability for Pension and Other Retirement Benefits (Textuals) [Abstract]
Percentage of employee benefits payable as pension					60.00%
Mandatory retirement age					60 years
Accumulated benefit obligations for defined benefit plans					$ 1,514,976,000	¥ 130,571,000,000	¥ 125,743,000,000
Plan assets, invested in equity securities					35.00%					35.00%
Plan assets, invested in debt securities					30.00%					65.00%
Plan assets, invested in other investment assets					35.00%
Common stock of Company included in Plan assets	494,000					48,000,000	41,000,000
Percentage of common stock of company included in plan assets					0.07%	0.08%
Government bonds and municipal bonds								50.00%	50.00%
Investment trusts hold by foreign subsidiaries		5,373,000	446,000,000	423,000,000
Expected contribution in next fiscal year							¥ 4,622,000,000			¥ 39,000,000