Finance Receivables, Net (Contractual Maturities on Retail Receivables and Dealer Financing) (Details) $ in Millions	Mar. 31, 2018 USD ($)
Retail receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2019	$ 14,348
2020	12,838
2021	10,702
2022	8,051
2023	5,232
Thereafter	2,224
Total	53,395
Dealer financing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2019	13,220
2020	1,527
2021	772
2022	667
2023	515
Thereafter	719
Total	$ 17,420

Notes receivables excluding estimated unguaranteed residual values in direct financing lease.

No definition available.

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Period Type:	instant

- Definition

Receivables to customers expected to be collected in or after five years from the balance sheet date.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Receivables to customers expected to be collected in less than five years but greater than four years from the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	tmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Receivables to customers expected to be collected in less than four years but greater than three years from the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	tmcc_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Receivables to customers expected to be collected within one year from the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	tmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Receivables to customers expected to be collected in less than three years but greater than two years from the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	tmcc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Receivables to customers expected to be collected in less than two years but greater than one year from the balance sheet date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- 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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Period Type:	duration

- Details

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- Details

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Period Type: