Related Party Transactions - Related Party Transactions Included in Consolidated Balance Sheets (Details) - USD ($) $ in Millions	Sep. 30, 2022	Mar. 31, 2022
Cash and cash equivalents
Cash and cash equivalents	$ 6,311	$ 7,670
TMCC-affiliated companies [Member]
Finance receivables, net
Accounts receivable	27	90
Deferred retail subvention income	(858)	(875)
Investments in operating leases, net
Investments in operating leases, net	(252)	(212)
Deferred lease subvention income	(624)	(923)
Other assets
Notes receivable	948	789
Other receivables, net	82	80
Other liabilities
Unearned voluntary protection contract revenues and insurance earned premiums	377	374
Other payables, net	528	394
Notes payable	61	8
Commercial paper [Member] \| TMCC-affiliated companies [Member]
Cash and cash equivalents
Cash and cash equivalents	$ 0	$ 100

Amount of deferred operating lease subvention revenue from related parties.

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Amount of deferred retail subvention revenue from related parties.

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The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

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Unearned voluntary protection contract revenues and insurance earned premiums.

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For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount payable to related parties classified as other.

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For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

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