Allowance for Credit Losses - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable Allowance For Credit Losses [Line Items]
Recoveries from credit loss charge-offs	$ 18	$ 19	$ 63	$ 59
Finance Receivables, Net [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance: Collectively evaluated for impairment	69,526	68,351	69,526	68,351
Finance Receivables, Net [Member] \| Retail and Commercial Loan [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Impaired finance receivables aggregated and collectively evaluated for impairment	222	219	222	219
Finance Receivables, Net [Member] \| Dealer Products [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance: Collectively evaluated for impairment	16,634	16,781	16,634	16,781
Finance Receivables, Net [Member] \| TMS [Member] \| Financial Guarantee [Member] \| Dealer Products [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance: Collectively evaluated for impairment	1,089	1,071	1,089	1,071
Finance Receivables, Net [Member] \| Private Toyota Distributors [Member] \| Financial Guarantee [Member] \| Dealer Products [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Ending balance: Collectively evaluated for impairment	$ 165	$ 173	$ 165	$ 173

Recorded investment of impaired financing receivables aggregated and evaluated for impairment.

No definition available.

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

+ Details

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- Details

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- Details

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- Details

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