Significant Accounting Policies Activity in Polaris Accrued Warranty Reserve (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Accounting Policies [Abstract]
Deferred tax liabilities	$ 5,357		$ 5,357		$ 6,490
Activity in Product Warranty Reserve [Roll Forward]
Balance at beginning of period	116,217	$ 116,286	121,824	$ 123,840
Additions to reserve related to acquisitions	8,809	0	8,809	0
Additions charged to expense	36,854	26,141	62,873	42,172
Warranty claims paid, net	(29,122)	(36,272)	(60,748)	(59,857)
Balance at end of period	$ 132,758	$ 106,155	$ 132,758	$ 106,155

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences, with jurisdictional netting and classified as noncurrent.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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Amount of increase in the standard and extended product warranty accrual from a business acquisition.

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Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

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Amount of increase in the standard and extended product warranty accrual from warranties issued.

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