Supplemental Consolidating Data (Operations) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2018	Jun. 25, 2017	Jul. 01, 2018	Jun. 25, 2017
Revenue:
Motorcycles and Related Products	$ 1,525,121	$ 1,577,135	$ 2,889,068	$ 2,905,846
Financial Services	188,102	188,034	366,276	361,255
Total revenue	1,713,223	1,765,169	3,255,344	3,267,101
Costs and expenses:
Motorcycles and Related Products cost of goods sold	993,036	1,004,173	1,883,210	1,858,061
Financial Services interest expense	51,943	44,408	100,393	87,697
Provision for credit losses	18,880	26,217	48,932	69,806
Selling, administrative and engineering expense	313,047	291,084	603,233	563,068
Restructuring expense	12,370	0	59,212	0
Total costs and expenses	1,389,276	1,365,882	2,694,980	2,578,632
Operating income	323,947	399,287	560,364	688,469
Other income (expense), net	645	2,295	865	4,591
Investment income	2,533	577	3,736	1,456
Interest expense	7,728	7,726	15,418	15,399
Income before provision for income taxes	319,397	394,433	549,547	679,117
Provision for income taxes	77,059	135,566	132,446	233,881
Net income	242,338	258,867	417,101	445,236
Reportable Legal Entities | Motorcycles And Related Products Operations
Revenue:
Motorcycles and Related Products	1,528,045	1,580,109	2,894,291	2,910,727
Financial Services	0	0	0	0
Total revenue	1,528,045	1,580,109	2,894,291	2,910,727
Costs and expenses:
Motorcycles and Related Products cost of goods sold	993,036	1,004,173	1,883,210	1,858,061
Financial Services interest expense	0	0	0	0
Provision for credit losses	0	0	0	0
Selling, administrative and engineering expense	276,827	256,147	531,228	494,777
Restructuring expense	12,370		59,212
Total costs and expenses	1,282,233	1,260,320	2,473,650	2,352,838
Operating income	245,812	319,789	420,641	557,889
Other income (expense), net	645	2,295	865	4,591
Investment income	2,533	577	113,736	107,456
Interest expense	7,728	7,726	15,418	15,399
Income before provision for income taxes	241,262	314,935	519,824	654,537
Provision for income taxes	59,683	106,035	99,916	185,192
Net income	181,579	208,900	419,908	469,345
Reportable Legal Entities | Financial Services Operations
Revenue:
Motorcycles and Related Products	0	0	0	0
Financial Services	188,788	188,712	367,248	362,269
Total revenue	188,788	188,712	367,248	362,269
Costs and expenses:
Motorcycles and Related Products cost of goods sold	0	0	0	0
Financial Services interest expense	51,943	44,408	100,393	87,697
Provision for credit losses	18,880	26,217	48,932	69,806
Selling, administrative and engineering expense	39,663	38,448	78,054	74,062
Restructuring expense	0		0
Total costs and expenses	110,486	109,073	227,379	231,565
Operating income	78,302	79,639	139,869	130,704
Other income (expense), net	0	0	0	0
Investment income	0	0	0	0
Interest expense	0	0	0	0
Income before provision for income taxes	78,302	79,639	139,869	130,704
Provision for income taxes	17,376	29,531	32,530	48,689
Net income	60,926	50,108	107,339	82,015
Eliminations
Revenue:
Motorcycles and Related Products	(2,924)	(2,974)	(5,223)	(4,881)
Financial Services	(686)	(678)	(972)	(1,014)
Total revenue	(3,610)	(3,652)	(6,195)	(5,895)
Costs and expenses:
Motorcycles and Related Products cost of goods sold	0	0	0	0
Financial Services interest expense	0	0	0	0
Provision for credit losses	0	0	0	0
Selling, administrative and engineering expense	(3,443)	(3,511)	(6,049)	(5,771)
Restructuring expense	0		0
Total costs and expenses	(3,443)	(3,511)	(6,049)	(5,771)
Operating income	(167)	(141)	(146)	(124)
Other income (expense), net	0	0	0	0
Investment income	0	0	(110,000)	(106,000)
Interest expense	0	0	0	0
Income before provision for income taxes	(167)	(141)	(110,146)	(106,124)
Provision for income taxes	0	0	0	0
Net income	$ (167)	$ (141)	$ (110,146)	$ (106,124)