Finance Receivables, Credit Quality Information, and Allowance for Credit Losses - Tabular Disclosure of Impaired Financing Receivables (Detail) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired receivables specifically evaluated	$ 29,620	$ 26,585
Finance receivables evaluated collectively	943,814	905,658
Finance receivables	973,434	932,243	$ 847,238
Impaired receivables in nonaccrual status	3,456	3,716
Amount of the specific reserve for impaired accounts	11,676	11,204
Amount of the general component of the allowance	45,524	47,096
Small Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired receivables specifically evaluated	9,839	8,361
Finance receivables evaluated collectively	421,375	429,301
Finance receivables	431,214	437,662	384,690
Impaired receivables in nonaccrual status	1,073	1,209
Amount of the specific reserve for impaired accounts	4,135	3,791
Amount of the general component of the allowance	24,999	26,968
Large Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired receivables specifically evaluated	18,849	17,196
Finance receivables evaluated collectively	479,908	420,802
Finance receivables	498,757	437,998	392,101
Impaired receivables in nonaccrual status	2,187	2,292
Amount of the specific reserve for impaired accounts	7,089	6,860
Amount of the general component of the allowance	17,965	16,842
Automobile Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired receivables specifically evaluated	799	918
Finance receivables evaluated collectively	14,887	25,236
Finance receivables	15,686	26,154	39,414
Impaired receivables in nonaccrual status	152	178
Amount of the specific reserve for impaired accounts	380	492
Amount of the general component of the allowance	713	1,401
Retail Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired receivables specifically evaluated	133	110
Finance receivables evaluated collectively	27,644	30,319
Finance receivables	27,777	30,429	$ 31,033
Impaired receivables in nonaccrual status	44	37
Amount of the specific reserve for impaired accounts	72	61
Amount of the general component of the allowance	$ 1,847	$ 1,885

The amount of allowance for credit losses excluding the specific reserve associated with impaired accounts.

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount of allowance for credit losses related to recorded investment.

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- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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