Composition of Long Term Debt, Weighted Average Contract Interest Rate on Long Term Debt and Repayment Due Dates (Detail) In Millions, unless otherwise specified			12 Months Ended		12 Months Ended		12 Months Ended
Mar. 31, 2011 USD ($)	Mar. 31, 2011 JPY (¥)	Mar. 31, 2010 JPY (¥)	Mar. 31, 2011 Banks Fixed Rate USD ($)	Mar. 31, 2011 Banks Fixed Rate JPY (¥)	Mar. 31, 2010 Banks Fixed Rate JPY (¥)	Mar. 31, 2011 Banks Floating Rate USD ($)	Mar. 31, 2011 Banks Floating Rate JPY (¥)	Mar. 31, 2010 Banks Floating Rate JPY (¥)	Mar. 31, 2011 Insurance Companies And Others Fixed Rate USD ($)	Mar. 31, 2011 Insurance Companies And Others Fixed Rate JPY (¥)	Mar. 31, 2010 Insurance Companies And Others Fixed Rate JPY (¥)	Mar. 31, 2011 Insurance Companies And Others Floating Rate USD ($)	Mar. 31, 2011 Insurance Companies And Others Floating Rate JPY (¥)	Mar. 31, 2010 Insurance Companies And Others Floating Rate JPY (¥)	Mar. 31, 2011 Unsecured Bonds USD ($)	Mar. 31, 2011 Unsecured Bonds JPY (¥)	Mar. 31, 2010 Unsecured Bonds JPY (¥)	Mar. 31, 2011 Unsecured Convertible Bonds With Stock Acquisition Rights	Mar. 31, 2010 Unsecured Convertible Bonds With Stock Acquisition Rights JPY (¥)	Mar. 31, 2011 Unsecured Convertible Bonds With Stock Acquisition Rights USD ($)	Mar. 31, 2011 Unsecured Convertible Bonds With Stock Acquisition Rights JPY (¥)	Mar. 31, 2011 Unsecured Bond With Stock Acquisition Rights JPY (¥)	Mar. 31, 2010 Unsecured Bond With Stock Acquisition Rights JPY (¥)	Mar. 31, 2011 Unsecured Bond With Stock Acquisition Rights USD ($)	Mar. 31, 2011 Unsecured Notes Under Medium Term Note Program USD ($)	Mar. 31, 2011 Unsecured Notes Under Medium Term Note Program JPY (¥)	Mar. 31, 2010 Unsecured Notes Under Medium Term Note Program JPY (¥)	Mar. 31, 2011 Payables Under Securitized Lease Receivables USD ($)	Mar. 31, 2011 Payables Under Securitized Lease Receivables JPY (¥)	Mar. 31, 2010 Payables Under Securitized Lease Receivables JPY (¥)	Mar. 31, 2011 Payables Under Securitized Loan Receivables And Investment In Securities USD ($)	Mar. 31, 2011 Payables Under Securitized Loan Receivables And Investment In Securities JPY (¥)	Mar. 31, 2010 Payables Under Securitized Loan Receivables And Investment In Securities JPY (¥)
Debt Instrument [Line Items]
Minimum maturity date				2012	2012	2011	2012	2012	2011	2012	2012	2011	2012	2012	2011	2012	2012	2011								2012	2012	2011	2012	2012	2011	2012	2012	2011
Maximum maturity date				2025	2025	2025	2026	2026	2025	2018	2018	2018	2028	2028	2028	2021	2021	2019								2018	2018	2018	2016	2016	2016	2039	2039	2026
Maturity date																			2014	2014			2023	2023
Long-Term Debt	$ 54,495	¥ 4,531,268	¥ 3,836,270	$ 2,897	¥ 240,904	¥ 293,479	$ 15,200	¥ 1,263,844	¥ 1,406,442	$ 3,909	¥ 325,006	¥ 372,556	$ 2,806	¥ 233,345	¥ 241,900	$ 14,162	¥ 1,177,582	¥ 1,028,994		¥ 149,987	$ 1,804	¥ 149,974	¥ 34,233	¥ 36,378	$ 412	$ 1,061	¥ 88,190	¥ 104,310	$ 2,054	¥ 170,820	¥ 101,860	$ 10,190	¥ 847,370	¥ 100,364
Weighted average rate	2.10%	2.10%	1.50%	2.80%	2.80%	2.60%	1.30%	1.30%	1.20%	1.80%	1.80%	1.70%	1.10%	1.10%	1.10%	1.90%	1.90%	1.80%		1.00%	1.00%	1.00%		0.00%	0.00%	1.90%	1.90%	1.60%	1.50%	1.50%	1.80%	4.30%	4.30%	0.90%

Debt Instrument Maturity Date Year

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- Definition

Debt Instrument, Weighted Average Interest Rate

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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When presenting a range of maturity dates, the latest date when the outstanding debt instruments are required to be repaid. May be presented in a variety of ways (for example: year only, month and year, day, month and year, and number of years).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 2, 4

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When presenting a range of maturity dates, the earliest date when the outstanding debt instruments are required to be repaid. May be presented in a variety of ways (for example: year only, month and year, day, month and year, and number of years).

+ References

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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

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20, 22
-Article 5

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