- Financial Information for Polaris Acceptance Reflecting Effects of Securitization Facility (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Polaris Acceptance
Schedule of Investments [Line Items]
Revenues	$ 79,276	$ 72,093	$ 61,645
Interest and operating expenses	14,337	11,832	7,590
Net income	64,939	60,261	$ 54,055
Finance receivables, net	687,646	573,669
Other assets	105	102
Total Assets	687,751	573,771
Notes payable/(receivable)	(463,055)	(386,438)
Other liabilities	3,414	3,215
Partners' capital	221,282	184,118
Total Liabilities and Partners' Capital	$ 687,751	$ 573,771
Maximum
Schedule of Investments [Line Items]
Aggregate repurchase obligation	15.00%
Polaris Acceptance | Maximum
Schedule of Investments [Line Items]
Aggregate repurchase obligation	15.00%