Quarterly report pursuant to Section 13 or 15(d)

Finance Receivables - Original Product - Schedule of Finance Receivables for Original Product (Detail)

v3.19.3
Finance Receivables - Original Product - Schedule of Finance Receivables for Original Product (Detail) - Original Product [Member]
9 Months Ended 12 Months Ended
Sep. 30, 2019
USD ($)
Unit
Dec. 31, 2018
USD ($)
Unit
Accounts Notes And Loans Receivable [Line Items]    
Finance receivables outstanding $ 421,243 $ 550,000
Reserve for credit losses (112,000) (125,000)
Finance receivables, net $ 309,243 $ 425,000
Number of active units with delinquent assessments | Unit 638 826
Amount of outstanding interest and late fees on active units $ 9,931,000 $ 11,268,000
Funded During The Current Year [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Finance receivables outstanding 34,000 79,000
1-2 Years Outstanding [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Finance receivables outstanding 22,000 35,000
2-3 Years Outstanding [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Finance receivables outstanding 21,000 18,000
3-4 Years Outstanding [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Finance receivables outstanding 11,000 7,000
Greater Than 4 Years Outstanding [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Finance receivables outstanding $ 333,243 $ 411,000