Restructuring Expense (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended
	Feb. 28, 2011	Mar. 31, 2013
2011 Restructuring Plan [Member] | Kansas City Facility [Member]
Restructuring Cost and Reserve [Line Items]
Estimated reduction in workforce		145
Estimated percentage of restructuring charges that will be non-cash		10.00%
Cumulative restructuring and impairment expenses		$ 6.9
Labor agreement period (in years)	7
2011 Restructuring Plan [Member] | NewCastallyFaciltiy [Member]
Restructuring Cost and Reserve [Line Items]
Estimated reduction in workforce		200
Estimated restructuring expense		31
Estimated percentage of restructuring charges that will be non-cash		35.00%
Cumulative restructuring and impairment expenses		25.2
Incurred restructuring and impairment expense		3.0
2010 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Estimated percentage of restructuring charges that will be non-cash		45.00%
Cumulative restructuring and impairment expenses		59.7
2010 Restructuring Plan [Member] | Milwaukee Facilities [Member]
Restructuring Cost and Reserve [Line Items]
Estimated reduction in workforce		250
2010 Restructuring Plan [Member] | Tomahawk Facilities [Member]
Restructuring Cost and Reserve [Line Items]
Estimated reduction in workforce		75
2009 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring expense		397
Estimated percentage of restructuring charges that will be non-cash		30.00%
Cumulative restructuring and impairment expenses		$ 395.3
Reduction in hourly production positions, minimum		2,700
Reduction in hourly production positions, maximum		2,900
2009 Restructuring Plan [Member] | Motorcycles [Member]
Restructuring Cost and Reserve [Line Items]
Estimated reduction in salaried positions from restructuring		800
2009 Restructuring Plan [Member] | Financial Services [Member]
Restructuring Cost and Reserve [Line Items]
Estimated reduction in salaried positions from restructuring		100