Related Party Transactions - Related Party Transactions Included in Consolidated Balance Sheets (Details) - USD ($) $ in Millions	Jun. 30, 2017	Mar. 31, 2017
Finance receivables, net
Accounts receivable	$ 147	$ 136
Notes receivable under home loan programs	2	2
Deferred retail subvention income	(1,009)	(967)
Investments in operating leases, net
Investments in operating leases, net	38,361	38,152
Deferred lease subvention income	(1,272)	(1,174)
Other assets
Notes receivable from affiliates	818	823
Other receivables, net	227	202
Other liabilities
Unearned insurance premiums and contract revenues	2,188	2,154
Other payables, net	52	74
Notes payable	24	13
TMCC-affiliated companies [Member]
Cash and cash equivalents
Investments in commercial paper	3	0
Investments in operating leases, net
Investments in operating leases, net	5	4
Other liabilities
Unearned insurance premiums and contract revenues	$ 333	$ 332

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 unclassified amount of notes receivable from certain officers, directors, other members of management, and relocated employees under home loan programs.

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

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Unsecured short-term debt instrument issued by corporations which are 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. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Amount receivable from related parties classified as other.

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Amount payable to related parties classified as other.

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The amount for notes payable (written promise to pay), due to related parties.

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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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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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Carrying amount of premiums written on insurance contracts that have not been earned as of the balance sheet date.

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