- Financial Information for Polaris Acceptance Reflecting Effects of Securitization Facility (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Polaris Acceptance
Schedule of Investments [Line Items]
Revenues	$ 66,414	$ 63,548	$ 40,968
Interest and operating expenses	6,182	4,738	3,678
Net income	60,232	58,810	$ 37,290
Finance receivables, net	479,944	472,029
Other assets	200	124
Total Assets	480,144	472,153
Notes payable/(receivable)	(288,275)	(269,881)
Other liabilities	3,851	4,126
Partners' capital	188,018	198,146
Total Liabilities and Partners' Capital	$ 480,144	$ 472,153
Maximum
Schedule of Investments [Line Items]
Aggregate repurchase obligation	15.00%