Defined Benefit Obligation Benefits Paid.

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The pretax total of net (gain) loss, prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 5
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The pretax net amount of gains and losses that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases or decreases in other comprehensive income as they arise. Gains and losses are due to changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

+ References

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Amount related to the pretax cost of benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost.

+ References

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The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

+ References

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

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The net increase or decrease of changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

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- Definition

The aggregate net amount recognized in the balance sheet associated with the defined benefit plan(s). Will normally be the same as the Defined Benefit Plan, Funded Status of Plan, Total.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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This represents the entire assets recognized in the balance sheet that are associated with the defined benefit plans.

+ References

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

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. The projected benefit obligation is measured using assumptions as to future compensation levels if the pension benefit formula is based on those future compensation levels (pay-related, final-pay, final-average-pay, or career-average-pay plans). For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date. Prior to an employee's full eligibility date, the accumulated postretirement benefit obligation as of a particular date for an employee is the portion of the expected postretirement benefit obligation attributed to that employee's service rendered to that date; on and after the full eligibility date, the accumulated and expected postretirement benefit obligations for an employee are the same.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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-Name Statement of Financial Accounting Standard (FAS)
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- Definition

The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name FASB Staff Position (FSP)
-Number FAS106-2
-Paragraph 22

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

The amount of contributions made by the employer.

+ References

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

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- Definition

The amount of contributions made by plan participants. Under a contributory plan active employees or retirees contribute part of the cost. In some contributory plans, those wishing to be covered must contribute; in others, the contributions result in increased benefits.

+ References

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

The amount of decrease that is related to an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those nonbenefit obligations may be considered as reductions of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 49

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- Definition

The amount of increase or decrease in the benefit obligation attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
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The amount of increase or decrease in plan assets attributed to foreign currency changes. The effects of foreign currency exchange rate changes that are to be disclosed are those applicable to plans of a foreign operation whose functional currency is not the reporting currency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

+ References

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

Amount of the period's gross receipts received from the prescription drug subsidy, which is to be used in the roll forward of the accumulated postretirement benefit obligation of an applicable postretirement benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS106-2
-Paragraph 20, 21, 22

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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For a classified balance sheet, the amount recognized in balance sheet as a current liability associated with an underfunded defined benefit plan.

+ References

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This represents the noncurrent liability for underfunded plans recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement defined benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
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Liability for Pension and Other Retirement Benefits (Details 9)				12 Months Ended
	Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)	Mar. 31, 2011 Other Postretirement Benefit Plans, Defined Benefit [Member] USD ($)	Mar. 31, 2011 Other Postretirement Benefit Plans, Defined Benefit [Member] JPY (¥)	Mar. 31, 2010 Other Postretirement Benefit Plans, Defined Benefit [Member] JPY (¥)	Mar. 31, 2009 Other Postretirement Benefit Plans, Defined Benefit [Member] JPY (¥)
Change in accumulated postretirement benefit obligation:
Accumulated postretirement benefit obligation, beginning of year				$ 113,446,000	¥ 9,416,000,000	¥ 9,069,000,000
Service cost - Benefit earned during the year				2,735,000	227,000,000	231,000,000	311,000,000
Interest cost on projected benefit obligation				5,446,000	452,000,000	528,000,000	575,000,000
Actuarial loss				(1,615,000)	(134,000,000)	979,000,000
Curtailment						(456,000,000)
Plan participants' contributions				24,000	2,000,000	2,000,000
Medicare Part D				663,000	55,000,000	68,000,000
Benefits paid				(8,771,000)	(728,000,000)	(659,000,000)
Foreign currency exchange rate change				(11,820,000)	(981,000,000)	(346,000,000)
Benefit obligation, end of year				100,108,000	8,309,000,000	9,416,000,000	9,069,000,000
Change in plan assets:
Fair value of plan assets, beginning of year				74,120,000	6,152,000,000	6,579,000,000
Actual return on plan assets				5,108,000	424,000,000	1,156,000,000
Employer contributions				8,747,000	726,000,000	657,000,000
Plan participants' contributions				24,000	2,000,000	2,000,000
Benefits paid				(15,698,000)	(1,303,000,000)	(1,894,000,000)
Foreign currency exchange rate change				(7,831,000)	(650,000,000)	(348,000,000)
Fair value of plan assets, end of year				64,470,000	5,351,000,000	6,152,000,000	6,579,000,000
Funded status, end of year				(35,638,000)	(2,958,000,000)	(3,264,000,000)
Prepaid benefit cost				8,663,000	719,000,000	700,000,000
Other current liability				(458,000)	(38,000,000)	(38,000,000)
Accrued benefit liability	578,639,000	48,027,000,000	46,354,000,000	(43,843,000)	(3,639,000,000)	(3,926,000,000)
Total				(35,638,000)	(2,958,000,000)	(3,264,000,000)
Amounts recognized in accumulated other comprehensive income (loss):
Actuarial loss				36,747,000	3,050,000,000	3,502,000,000
Prior service cost				6,639,000	551,000,000	616,000,000
Total				$ 43,386,000	¥ 3,601,000,000	¥ 4,118,000,000