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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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.

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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.

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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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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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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.

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This represents the entire assets recognized in the balance sheet that are associated with the defined benefit plans.

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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.

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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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-Name FASB Staff Position (FSP)
-Number FAS106-2
-Paragraph 22

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- Definition

The amount of increase in the benefit obligation attributed to business combinations.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
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The amount of increase in the plan assets attributed to a business combination.

+ References

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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.

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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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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.

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-Name Statement of Financial Accounting Standard (FAS)
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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
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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.

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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.

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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.

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The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

+ 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.

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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.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
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Liability for Pension and Other Retirement Benefits (Details)				12 Months Ended
	Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)	Mar. 31, 2011 Pension Plans, Defined Benefit [Member] USD ($)	Mar. 31, 2011 Pension Plans, Defined Benefit [Member] JPY (¥)	Mar. 31, 2010 Pension Plans, Defined Benefit [Member] JPY (¥)	Mar. 31, 2009 Pension Plans, Defined Benefit [Member] JPY (¥)	Mar. 31, 2010 Pension Plans, Defined Benefit [Member] USD ($)
Change in benefit obligation:
Benefit obligation, beginning of year				$ 1,618,795,000	¥ 134,360,000,000	¥ 137,452,000,000	¥ 139,569,000,000	$ 1,656,048,000
Service cost - Benefit earned during the year				79,880,000	6,630,000,000	7,224,000,000	8,460,000,000
Interest cost on projected benefit obligation				43,193,000	3,585,000,000	3,745,000,000	3,885,000,000
Actuarial loss				22,337,000	1,854,000,000	4,048,000,000
Plan participants' contributions				663,000	55,000,000	49,000,000
Acquisition				1,506,000	125,000,000
Plan amendment						208,000,000
Benefits paid				(162,711,000)	(13,505,000,000)	(17,446,000,000)
Foreign currency exchange rate change				(22,121,000)	(1,836,000,000)	55,000,000
Benefit obligation, end of year				1,618,795,000	134,360,000,000	137,452,000,000	139,569,000,000	1,656,048,000
Change in plan assets:
Fair value of plan assets, beginning of year				1,137,386,000	94,403,000,000	88,252,000,000
Actual return on plan assets				3,024,000	251,000,000	10,329,000,000
Employer contributions				88,169,000	7,318,000,000	6,465,000,000
Plan participants' contributions				663,000	55,000,000	49,000,000
Acquisition				663,000	55,000,000
Benefits paid				(100,976,000)	(8,381,000,000)	(10,788,000,000)
Foreign currency exchange rate change				(16,989,000)	(1,410,000,000)	96,000,000
Fair value of plan assets, end of year				1,111,940,000	92,291,000,000	94,403,000,000	88,252,000,000
Funded status, end of year				(506,855,000)	(42,069,000,000)	(43,049,000,000)
Prepaid benefit cost				24,096,000	2,000,000,000	22,000,000
Other current liability				(590,000)	(49,000,000)	(89,000,000)
Accrued benefit liability	578,639,000	48,027,000,000	46,354,000,000	(530,361,000)	(44,020,000,000)	(42,982,000,000)
Total				(506,855,000)	(42,069,000,000)	(43,049,000,000)
Amounts recognized in accumulated other comprehensive income (loss):
Actuarial loss				444,843,000	36,922,000,000	34,979,000,000
Prior service cost				17,964,000	1,491,000,000	1,370,000,000
Total				$ 462,807,000	¥ 38,413,000,000	¥ 36,349,000,000