Short-Term Borrowings and Long-Term Debt (Aggregate Amounts of Annual Maturities of Long-Term Debt) (Detail) - JPY (¥) ¥ in Millions	Mar. 31, 2019	Mar. 31, 2018
Debt Disclosure [Abstract]
2020	¥ 172,461
2021	41,466
2022	186,004
2023	227,987
2024	18,102
Later fiscal years	94,813
Total	¥ 740,833	¥ 848,973

No definition available.

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Amount of long-term debt and capital lease obligations including current maturities.

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Principal amount of long-term debt and capital lease obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Principal amount of long-term debt and capital lease obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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Principal amount of long-term debt and capital lease obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Principal amount of long-term debt and capital lease obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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Principal amount of long-term debt and capital lease obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Principal amount of long-term debt and capital lease obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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