Finance Receivables - Summary of contracts included in finance receivables (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Indirect finance receivables, net	$ 269,876	$ 317,205
Finance receivables \| Contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Indirect finance receivables, gross contract	423,900	502,050	$ 487,118
Unearned interest	(127,994)	(158,541)	(152,911)
Indirect finance receivables, net of unearned interest	295,906	343,509	334,207
Unearned dealer discounts	(13,655)	(17,004)	(18,023)
Indirect finance receivables, net of unearned interest and unearned dealer discounts	282,251	326,505	316,184
Allowance for credit losses	(19,433)	(16,885)	(12,265)	$ (11,325)
Indirect finance receivables, net	$ 262,818	$ 309,620	$ 303,919

Represents amount of indirect finance receivables, net of unearned interest and unearned dealer discounts.

No definition available.

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- Definition

Net amount of the investment after deducting the amount of unearned discounts (other than cash or quantity discounts and the like), finance charges, and interest included.

+ References

No definition available.

+ Details

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- Definition

Represents unearned discounts (other than cash or quantity discounts and the like) included in the net amount of finance receivables, that are shown as a deduction from the related receivables.

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No definition available.

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- Definition

Represents unearned interest included in financial receivables.

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No definition available.

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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.

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

+ Details

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- Definition

Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(3))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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