Restructuring Expense (Restructuring Plan Reserve Recorded in Accrued Liabilities) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2013	Sep. 30, 2012	Sep. 29, 2013	Sep. 30, 2012
Restructuring Reserve [Roll Forward]
Restructuring expense	$ 646	$ 9,170	$ (1,713)	$ 26,841
2011 Kansas City Restructuring Plan [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			2,259	4,123
Restructuring expense			0	0
Utilized—cash			(1,283)	0
Utilized—non-cash			0	0
Non-cash reserve release			(976)	(967)
Balance, end of period	0	3,156	0	3,156
2011 Kansas City Restructuring Plan [Member] | Employee Severance [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			2,259	4,123
Restructuring expense			0	0
Utilized—cash			(1,283)	0
Utilized—non-cash			0	0
Non-cash reserve release			(976)	(967)
Balance, end of period	0	3,156	0	3,156
2011 Kansas City Restructuring Plan [Member] | Other [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			0	0
Restructuring expense			0	0
Utilized—cash			0	0
Utilized—non-cash			0	0
Non-cash reserve release			0	0
Balance, end of period	0	0	0	0
2011 New Castalloy Restructuring Plan [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			9,451	8,733
Restructuring expense			4,044	9,677
Utilized—cash			(5,962)	(1,623)
Utilized—non-cash			(2,093)	(6,152)
Non-cash reserve release			(5,250)	0
Balance, end of period	190	10,635	190	10,635
2011 New Castalloy Restructuring Plan [Member] | Employee Severance [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			9,306	8,428
Restructuring expense			1,361	2,450
Utilized—cash			(5,360)	(388)
Utilized—non-cash			0	0
Non-cash reserve release			(5,250)	0
Balance, end of period	57	10,490	57	10,490
2011 New Castalloy Restructuring Plan [Member] | Other [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			145	305
Restructuring expense			590	1,075
Utilized—cash			(602)	(1,235)
Utilized—non-cash			0	0
Non-cash reserve release			0	0
Balance, end of period	133	145	133	145
2011 New Castalloy Restructuring Plan [Member] | Accelerated Depreciation [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			0	0
Restructuring expense			2,093	6,152
Utilized—cash			0	0
Utilized—non-cash			(2,093)	(6,152)
Non-cash reserve release			0	0
Balance, end of period	0	0	0	0
2011 Restructuring Plan [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			11,710	12,856
Restructuring expense			4,044	9,677
Utilized—cash			(7,245)	(1,623)
Utilized—non-cash			(2,093)	(6,152)
Non-cash reserve release			(6,226)	(967)
Balance, end of period	190	13,791	190	13,791
2010 Restructuring Plan [Member] | Employee Severance [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			10,156	20,361
Restructuring expense			0	4,005
Utilized—cash			(9,710)	(13,894)
Non-cash reserve release			(446)	0
Balance, end of period	0	10,472	0	10,472
2009 Restructuring Plan [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			5,357	10,089
Restructuring expense			2,446	16,153
Utilized—cash			(4,227)	(14,516)
Utilized—non-cash			0	0
Non-cash reserve release			(1,531)	(2,027)
Balance, end of period	2,045	9,699	2,045	9,699
2009 Restructuring Plan [Member] | Employee Severance [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			5,196	10,089
Restructuring expense			0	4,166
Utilized—cash			(1,620)	(2,529)
Utilized—non-cash			0	0
Non-cash reserve release			(1,531)	(2,027)
Balance, end of period	2,045	9,699	2,045	9,699
2009 Restructuring Plan [Member] | Other [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			161	0
Restructuring expense			2,446	11,987
Utilized—cash			(2,607)	(11,987)
Utilized—non-cash			0	0
Non-cash reserve release			0	0
Balance, end of period	0	0	0	0
2009 Restructuring Plan [Member] | Accelerated Depreciation [Member] | Motorcycles And Related Products [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning of period			0	0
Restructuring expense			0	0
Utilized—cash			0	0
Utilized—non-cash			0	0
Non-cash reserve release			0	0
Balance, end of period	$ 0	$ 0	$ 0	$ 0