Supplemental Consolidating Data (Operations) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 24, 2017	Sep. 25, 2016	Sep. 24, 2017	Sep. 25, 2016
Revenue:
Motorcycles and Related Products	$ 962,136	$ 1,091,630	$ 3,867,982	$ 4,338,353
Financial Services	189,059	183,183	550,314	547,505
Total revenue	1,151,195	1,274,813	4,418,296	4,885,858
Costs and expenses:
Motorcycles and Related Products cost of goods sold	685,161	724,611	2,537,899	2,773,496
Financial Services interest expense	46,169	42,573	133,866	131,387
Provision for credit losses	29,253	36,543	99,059	97,127
Selling, administrative and engineering expense	293,904	292,710	857,704	904,322
Total costs and expenses	1,054,487	1,096,437	3,628,528	3,906,332
Operating income	96,708	178,376	789,768	979,526
Investment income	1,083	2,300	2,539	3,754
Interest expense	7,896	7,706	23,295	21,968
Income before provision for income taxes	89,895	172,970	769,012	961,312
Provision for income taxes	21,686	58,905	255,567	316,327
Net income	68,209	114,065	513,445	644,985
Reportable Legal Entities | Motorcycles And Related Products Operations
Revenue:
Motorcycles and Related Products	964,942	1,094,148	3,875,669	4,346,166
Financial Services	0	0	0	0
Total revenue	964,942	1,094,148	3,875,669	4,346,166
Costs and expenses:
Motorcycles and Related Products cost of goods sold	685,161	724,611	2,537,899	2,773,496
Financial Services interest expense	0	0	0	0
Provision for credit losses	0	0	0	0
Selling, administrative and engineering expense	257,723	258,541	753,232	802,139
Total costs and expenses	942,884	983,152	3,291,131	3,575,635
Operating income	22,058	110,996	584,538	770,531
Investment income	91,083	2,300	198,539	186,754
Interest expense	7,896	7,706	23,295	21,968
Income before provision for income taxes	105,245	105,590	759,782	935,317
Provision for income taxes	(6,134)	33,895	179,058	238,256
Net income	111,379	71,695	580,724	697,061
Reportable Legal Entities | Financial Services Operations
Revenue:
Motorcycles and Related Products	0	0	0	0
Financial Services	189,932	183,706	552,201	549,162
Total revenue	189,932	183,706	552,201	549,162
Costs and expenses:
Motorcycles and Related Products cost of goods sold	0	0	0	0
Financial Services interest expense	46,169	42,573	133,866	131,387
Provision for credit losses	29,253	36,543	99,059	97,127
Selling, administrative and engineering expense	39,383	37,139	113,445	111,414
Total costs and expenses	114,805	116,255	346,370	339,928
Operating income	75,127	67,451	205,831	209,234
Investment income	0	0	0	0
Interest expense	0	0	0	0
Income before provision for income taxes	75,127	67,451	205,831	209,234
Provision for income taxes	27,820	25,010	76,509	78,071
Net income	47,307	42,441	129,322	131,163
Eliminations
Revenue:
Motorcycles and Related Products	(2,806)	(2,518)	(7,687)	(7,813)
Financial Services	(873)	(523)	(1,887)	(1,657)
Total revenue	(3,679)	(3,041)	(9,574)	(9,470)
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	(3,202)	(2,970)	(8,973)	(9,231)
Total costs and expenses	(3,202)	(2,970)	(8,973)	(9,231)
Operating income	(477)	(71)	(601)	(239)
Investment income	(90,000)	0	(196,000)	(183,000)
Interest expense	0	0	0	0
Income before provision for income taxes	(90,477)	(71)	(196,601)	(183,239)
Provision for income taxes	0	0	0	0
Net income	$ (90,477)	$ (71)	$ (196,601)	$ (183,239)