Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

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Derivative Instruments and Hedging Activities (Effects of Derivative Instruments on Consolidated Statements of Income) (Detail) - JPY (¥) ¥ in Millions	12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	¥ (3,925)	¥ (1,835)	¥ (52)
Derivative assets	42,383	10,486
Not designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	26,441	(26,476)	10,174
Derivative assets	40,548	10,244
Not designated as hedging instrument \| Interest rate contracts \| Financial services revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	1,190	(3,192)	(1,544)
Not designated as hedging instrument \| Foreign exchange contracts \| Financial services revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	2,473	(8,198)	2,013
Not designated as hedging instrument \| Foreign exchange contracts \| Foreign exchange loss, net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	10,184	(7,437)	21,370
Not designated as hedging instrument \| Equity Contracts \| Financial services revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	15,438	(7,649)	(11,665)
Not designated as hedging instrument \| Bond contracts \| Financial services revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	(2,954)
Not designated as hedging instrument \| Commodity contracts \| Financial services revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	110
Amortized Cost
Derivative Instruments, Gain (Loss) [Line Items]
Derivative assets	106,335
Amortized Cost \| Interest rate contracts \| Marketable securities
Derivative Instruments, Gain (Loss) [Line Items]
Derivative assets	15,255
Amortized Cost \| Interest rate contracts \| Securities investments and other
Derivative Instruments, Gain (Loss) [Line Items]
Derivative assets	91,080
Fair Value Hedging \| Interest rate contracts \| Financial services revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative	(3,925)	(1,835)	(52)
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from accumulated OCI into income (effective portion)	(981)	(1,093)	1,111
Unrealized gain (loss) on cash flow hedging instruments	2,799	2,315	(2,295)
Cash Flow Hedging \| Foreign exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in OCI on derivative	1,712	2,315	(2,295)
Gain (loss) from unrealized gains (losses)	1,087	0	0
Cash Flow Hedging \| Foreign exchange contracts \| Cost of Sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from accumulated OCI into income (effective portion)		¥ (1,093)	¥ 1,111
Cash Flow Hedging \| Foreign exchange contracts \| Net sales
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from accumulated OCI into income (effective portion)	106
Gain (loss) from unrealized gains (losses)	¥ (1,087)