Significant Accounting Policies Activity in Polaris Accrued Warranty Reserve (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Activity in Product Warranty Reserve [Roll Forward]
Balance at beginning of period	$ 44,811	$ 42,717	$ 52,818	$ 47,723
Additions to warranty reserve through acquisitions	0	0	110	1,602
Additions charged to expense	21,227	16,860	44,524	38,850
Warranty claims paid	(14,644)	(11,475)	(46,058)	(40,073)
Balance at end of period	$ 51,394	$ 48,102	$ 51,394	$ 48,102