Pledged Assets (Details) In Thousands	Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2011 Cash and Cash Equivalents [Member] USD ($)	Mar. 31, 2011 Cash and Cash Equivalents [Member] JPY (¥)	Mar. 31, 2011 Other current assets [Member] USD ($)	Mar. 31, 2011 Other current assets [Member] JPY (¥)	Mar. 31, 2011 Guarantees for debt [Member] USD ($)	Mar. 31, 2011 Guarantees for debt [Member] JPY (¥)
Assets pledged as collateral for long term debt and guarantees for debt
Assets pledged as collateral for long term debt and guarantees for debt	$ 31,036	¥ 2,576,000	$ 24	¥ 2,000	$ 31,012	¥ 2,574,000	$ 31,036	¥ 2,576,000

The carrying amount, as of the date of the latest financial statement presented, of all assets that are pledged as collateral for the payment of the related debt obligation primarily arising from secured borrowings, repurchase agreements or other current or potential obligations, where the secured party does not have the right by contract or custom to sell or re-pledge the collateral and therefore are not reclassified and separately reported in the statement of financial position.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS140-4 and FIN46(R)-8
-Paragraph B6
-Subparagraph b

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 17
-Subparagraph a(2)

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant