Borrowings - Maturities of Long-Term Borrowings (Detail) (JPY ¥) In Millions, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012
Schedule Of Borrowings [Line Items]
2014	¥ 701,517
2015	1,320,270
2016	1,140,710
2017	693,281
2018	805,937
2019 and thereafter	2,753,263
Subtotal	7,414,978	8,281,872
Trading balances of secured borrowings	177,390	222,968
Total	¥ 7,592,368	¥ 8,504,840

Long-term Debt, Maturities, Repayments of Principal

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

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Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

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