Supplemental Consolidating Data (Operations) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2018	Mar. 26, 2017
Revenue:
Motorcycles and Related Products	$ 1,363,947	$ 1,328,711
Financial Services	178,174	173,221
Total revenue	1,542,121	1,501,932
Costs and expenses:
Motorcycles and Related Products cost of goods sold	890,174	853,888
Financial Services interest expense	48,450	43,289
Provision for credit losses	30,052	43,589
Selling, administrative and engineering expense	290,186	271,984
Restructuring expense	46,842	0
Total costs and expenses	1,305,704	1,212,750
Operating income	236,417	289,182
Other income (expense), net	220	2,296
Investment income	1,203	879
Interest expense	7,690	7,673
Income before provision for income taxes	230,150	284,684
Provision for income taxes	55,387	98,315
Net income	174,763	186,369
Reportable Legal Entities | Motorcycles And Related Products Operations
Revenue:
Motorcycles and Related Products	1,366,246	1,330,618
Financial Services	0	0
Total revenue	1,366,246	1,330,618
Costs and expenses:
Motorcycles and Related Products cost of goods sold	890,174	853,888
Financial Services interest expense	0	0
Provision for credit losses	0	0
Selling, administrative and engineering expense	254,401	238,630
Restructuring expense	46,842
Total costs and expenses	1,191,417	1,092,518
Operating income	174,829	238,100
Other income (expense), net	220	2,296
Investment income	111,203	106,879
Interest expense	7,690	7,673
Income before provision for income taxes	278,562	339,602
Provision for income taxes	40,233	79,157
Net income	238,329	260,445
Reportable Legal Entities | Financial Services Operations
Revenue:
Motorcycles and Related Products	0	0
Financial Services	178,460	173,557
Total revenue	178,460	173,557
Costs and expenses:
Motorcycles and Related Products cost of goods sold	0	0
Financial Services interest expense	48,450	43,289
Provision for credit losses	30,052	43,589
Selling, administrative and engineering expense	38,391	35,614
Restructuring expense	0
Total costs and expenses	116,893	122,492
Operating income	61,567	51,065
Other income (expense), net	0	0
Investment income	0	0
Interest expense	0	0
Income before provision for income taxes	61,567	51,065
Provision for income taxes	15,154	19,158
Net income	46,413	31,907
Eliminations
Revenue:
Motorcycles and Related Products	(2,299)	(1,907)
Financial Services	(286)	(336)
Total revenue	(2,585)	(2,243)
Costs and expenses:
Motorcycles and Related Products cost of goods sold	0	0
Financial Services interest expense	0	0
Provision for credit losses	0	0
Selling, administrative and engineering expense	(2,606)	(2,260)
Restructuring expense	0
Total costs and expenses	(2,606)	(2,260)
Operating income	21	17
Other income (expense), net	0	0
Investment income	(110,000)	(106,000)
Interest expense	0	0
Income before provision for income taxes	(109,979)	(105,983)
Provision for income taxes	0	0
Net income	$ (109,979)	$ (105,983)