Net Deferred Tax Assets and Liabilities Reflected in Accompanying Consolidated Balance Sheets (Detail) In Millions	Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)
Schedule of Deferred Income Tax Assets and Liabilities [Line Items]
Other assets	$ 1,095	¥ 91,063	¥ 83,483
Income taxes: Deferred	1,930	160,518	160,905
Net deferred tax liability	$ 835	¥ 69,455	¥ 77,422

Deferred Tax Assets, Other Assets

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- Definition

Schedule of Deferred Income Tax Assets and Liabilities [Line Items]

+ Details

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- Definition

The cumulative amount for all deferred tax liabilities as of the balance sheet date arising from temporary differences between accounting income in accordance with generally accepted accounting principles and tax-basis income that will result in future taxable income exceeding future accounting income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 43, 289

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 15
-Subparagraph b(2)
-Article 7

+ Details

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- Definition

For entities that net deferred tax assets and tax liabilities, represents the unclassified net amount of deferred tax assets and liabilities as of the balance sheet date, which result from applying the applicable enacted tax rate to net temporary differences and carryforwards pertaining to assets or liabilities. A temporary difference is a difference between the tax basis of an asset or liability and its carrying amount in the financial statements prepared in accordance with generally accepted accounting principles that will reverse in ensuing periods.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 42, 43

+ Details

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