Retirement And Pension Plans (Schedule Of Amounts Recognized In Other Comprehensive Income (Loss), Before Tax) (Detail) (JPY ¥) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Retirement And Pension Plans [Abstract]
Actuarial gain (loss) recognized in other comprehensive income	¥ (12,529)	¥ (4,602)	¥ 7,712
Reclassification adjustment for prior service benefit realized in net income	(808)	(808)	(808)
Reclassification adjustment for actuarial loss realized in net income	693	472	9,611
Net recognized in other comprehensive income (loss), before tax	¥ (12,644)	¥ (4,938)	¥ 16,515

Amounts recognized in other comprehensive income (but not yet recognized in net periodic benefit cost), including the net gain (loss) and net prior service cost (credit) arising during the period. Also includes reclassification adjustments out of other comprehensive income as a result of being recognized as components of net periodic benefit cost for the period. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

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-Name Regulation S-X (SX)

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-Name Accounting Research Bulletin (ARB)

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+ Details

- Definition

Pretax change 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, that has not been recognized in net periodic benefit cost.

+ References

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+ Details