Supplemental Cash Flow Information (Details) In Thousands	12 Months Ended
Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)	Mar. 31, 2009 JPY (¥)
Additional cash flow information:
Interest paid	$ 76,711	¥ 6,367,000	¥ 8,533,000	¥ 14,403,000
Income taxes paid	556,952	46,227,000	9,797,000	111,508,000
Noncash investing and financing activities:
Capital lease obligations incurred	$ 27,036	¥ 2,244,000	¥ 14,285,000	¥ 29,762,000

The increase during the period in capital lease obligations due to entering into new capital leases.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 32

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 29

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 27
-Subparagraph f

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 95
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