Finance Receivables - Summary of contracts included in finance receivables (Details) (USD $)	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011	Mar. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Indirect finance receivables, gross contract	$ 4,132,000	$ 2,572,000	$ 2,035,000
Indirect finance receivables, net	249,825,801	241,253,430
Contracts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Indirect finance receivables, gross contract	386,940,093	382,766,667	368,099,418
Unearned interest	(111,121,493)	(109,456,018)	(105,622,007)
Indirect finance receivables, net of unearned interest	275,818,600	273,310,649	262,477,411
Unearned dealer discounts	(16,415,169)	(17,091,567)	(17,024,119)
Indirect finance receivables, net of unearned interest and unearned dealer discounts	259,403,431	256,219,082	245,453,292
Allowance for credit losses	(16,090,652)	(19,499,208)	(19,952,595)	(16,383,893)
Indirect finance receivables, net	$ 243,312,779	$ 236,719,874	$ 225,500,697

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 indirect finance receivables, that are shown as a deduction from the related receivables.

+ References

No definition available.

+ Details

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- Definition

Represents unearned interest included in the face amount of indirect finance receivables, that are shown as a deduction from the related receivables.

+ References

No definition available.

+ Details

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- Details

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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=7512638&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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Subparagraph 3

-Article 9

+ Details

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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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Article 5

+ Details

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