Derivative Financial Instruments (Details 3) (Cash Flow Hedging [Member]) In Thousands	12 Months Ended
Mar. 31, 2011 Interest rate swaps cross-currency swap and interest rate cap agreements [Member] Other income (expenses), net [Member] USD ($)	Mar. 31, 2010 Interest rate swaps cross-currency swap and interest rate cap agreements [Member] Other income (expenses), net [Member] JPY (¥)	Mar. 31, 2011 Interest rate swaps cross-currency swap and interest rate cap agreements [Member] USD ($)	Mar. 31, 2011 Interest rate swaps cross-currency swap and interest rate cap agreements [Member] JPY (¥)	Mar. 31, 2010 Interest rate swaps cross-currency swap and interest rate cap agreements [Member] JPY (¥)	Mar. 31, 2009 Interest rate swaps cross-currency swap and interest rate cap agreements [Member] JPY (¥)	Mar. 31, 2011 Forwards contracts [Member] Other income (expenses), net [Member] USD ($)	Mar. 31, 2011 Forwards contracts [Member] Other income (expenses), net [Member] JPY (¥)	Mar. 31, 2010 Forwards contracts [Member] Other income (expenses), net [Member] JPY (¥)	Mar. 31, 2009 Forwards contracts [Member] Other income (expenses), net [Member] JPY (¥)	Mar. 31, 2011 Forwards contracts [Member] JPY (¥)	Mar. 31, 2011 Forwards contracts [Member] USD ($)	Mar. 31, 2010 Forwards contracts [Member] JPY (¥)	Mar. 31, 2009 Forwards contracts [Member] JPY (¥)	Mar. 31, 2011 Other income (expenses), net [Member] JPY (¥)	Mar. 31, 2010 Other income (expenses), net [Member] JPY (¥)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2011 USD ($)	Mar. 31, 2010 JPY (¥)	Mar. 31, 2009 JPY (¥)
Derivative instruments designated as cash flow hedging relationships
Amount of gains (losses) recognized in OCI on derivatives			$ 1,446	¥ 120,000	¥ 1,758,000	¥ 65,000					¥ 7,195,000	$ 86,687	¥ 363,000	¥ 790,000			¥ 7,315,000	$ 88,133	¥ 2,121,000	¥ 855,000
Amount gains (losses) reclassified from accumulated OCI into income	0	89,000					90,060	7,475,000	532,000	2,892,000							7,475,000	90,060	621,000	2,892,000
Amount of gains (losses) recognized in income on derivatives							$ 0	¥ 0	¥ 0						¥ 0	¥ 0	¥ 0	$ 0	¥ 0

Derivative instruments designated as cash flow hedging relationships.

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- Definition

The income statement location of the effective portion of net gain or loss reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 205G

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44C
-Subparagraph b
-Clause 3

+ Details

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

+ Details

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

+ Details

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