Investments in Affiliated Companies (Account Balances and Transactions with Affiliated Companies Accounted for under Equity Method) (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Schedule of Equity Method Investments [Line Items]
Short-term borrowings	¥ 618,618	¥ 496,093
Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Accounts receivable, trade	12,404	15,516
Accounts payable, trade	1,087	2,568
Short-term borrowings	29,744	22,849
Capital lease obligations	20,265	13,294
Sales	41,437	45,415	¥ 31,238
Purchases	5,584	3,180	1,966
Lease payments	¥ 7,455	¥ 7,749	¥ 16,492

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

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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.

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