Income Taxes (Schedule Of Reconciliation Of Unrecognized Tax Benefits) (Detail) (JPY ¥) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Income Taxes [Abstract]
Balance at beginning of year	¥ 223	¥ 200	¥ 6,759
Gross increase for tax positions taken in prior years	1,639	87	26
Gross decrease for tax positions taken in prior years		(9)	(2,029)
Settlements	(118)	(8)	(4,534)
Lapse of statute of limitations		(19)	(27)
Other	(7)	(28)	5
Balance at end of year	¥ 1,737	¥ 223	¥ 200

Unrecognized Tax Benefits Other

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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