Goodwill and Intangible Assets (Schedule of Finite-Lived Intangible Assets Future Amortization Expense) (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 25, 2016	Sep. 27, 2015	Sep. 25, 2016	Sep. 27, 2015	Jun. 26, 2016	Dec. 31, 2015	Jun. 28, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Amortization expense on intangible assets	$ 1,800,000	$ 1,200,000	$ 5,200,000	$ 1,200,000
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Goodwill	54,663,000	54,267,000	54,663,000	54,267,000		$ 54,182,000
Operating Segments | Motorcycles
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2016 (remaining 6 months)	1,767,000		1,767,000
2017	4,278,000		4,278,000
2018	372,000		372,000
2019	372,000		372,000
2020	372,000		372,000
2021	372,000		372,000
Thereafter	5,128,000		5,128,000
Net	12,661,000	19,361,000	12,661,000	19,361,000		16,954,000
Goodwill	54,663,000	54,267,000	54,663,000	54,267,000	$ 54,542,000	54,182,000	$ 26,105,000	$ 27,752,000
Operating Segments | Financial Services
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Net	0	0	0	0		0
Goodwill	$ 0	$ 0	$ 0	$ 0		$ 0