Short-Term Borrowings and Long-Term Debt (Schedule of Long-Term Debt) (Details) (JPY ¥) In Millions, unless otherwise specified	Mar. 31, 2011	Mar. 31, 2010
Unsecured bonds:
Collateralized	¥ 17,322	¥ 24,216
Unsecured	207,826	224,963
Capital lease obligations	3,118	5,986
Total	277,316	314,765
Less: current portion	(85,556)	(71,432)
Long-term debt	191,760	243,333
Yen Notes (Fixed Rate 1.20%) Due in Year 2011 [Member]
Unsecured bonds:
Unsecured		10,000
Due in years ending March 31:	2011
Interest rate on long-term debt	1.20%
Yen Notes (Floating Rate 0.70%) Due in Year 2012 [Member]
Unsecured bonds:
Unsecured	4,000	4,000
Due in years ending March 31:	2012
Interest rate on long-term debt	0.70%
Yen Notes (Floating Rate 0.75%) Due in Year 2013 [Member]
Unsecured bonds:
Unsecured	4,000	4,000
Due in years ending March 31:	2013
Interest rate on long-term debt	0.75%
Yen Notes (Floating Rate .75%) Due in Year 2013 [Member]
Unsecured bonds:
Unsecured	2,000	2,000
Due in years ending March 31:	2013
Interest rate on long-term debt	0.75%
Yen Notes (Floating Rate 0.47%) Due in Year 2013 [Member]
Unsecured bonds:
Unsecured	5,000	5,000
Due in years ending March 31:	2013
Interest rate on long-term debt	0.47%
U.S.$ Notes (Floating Rate 0.72%) Due in Year 2013 [Member]
Unsecured bonds:
Unsecured	4,050	4,600
Due in years ending March 31:	2013
Interest rate on long-term debt	0.72%
Yen Notes (Fixed Rate 1.54%) Due in Year 2013 [Member]
Unsecured bonds:
Unsecured	10,000	10,000
Due in years ending March 31:	2013
Interest rate on long-term debt	1.54%
Yen Notes (Fixed Rate 1.27%) Due in Year 2013 [Member]
Unsecured bonds:
Unsecured	10,000	10,000
Due in years ending March 31:	2013
Interest rate on long-term debt	1.27%
Yen Notes (Fixed Rate 1.53%) Due in Year 2015 [Member]
Unsecured bonds:
Unsecured	¥ 10,000	¥ 10,000
Due in years ending March 31:	2015
Interest rate on long-term debt	1.53%

Long Term Debt Maturity Date

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 7

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Interest rate stated in the contractual debt agreement.

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-Section 02
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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

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-Section 03
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-Paragraph 20, 22
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Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Carrying value as of the balance sheet date , including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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