Activity in Polaris Accrued Warranty Reserve (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Product Warranty Liability [Line Items]
Balance at beginning of year	$ 44,355	$ 32,651	$ 25,520
Additions to warranty reserve through acquisitions	900	2,727
Additions charged to expense	46,088	46,217	43,721
Warranty claims paid	(43,620)	(37,240)	(36,590)
Balance at end of year	$ 47,723	$ 44,355	$ 32,651