Finance Receivables (Changes In Allowance For Credit Losses On Finance Receivables) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 24, 2017	Sep. 25, 2016	Sep. 24, 2017	Sep. 25, 2016	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	$ 193,528	$ 161,353	$ 173,343	$ 147,178
Provision for credit losses	29,253	36,543	99,059	97,127
Charge-offs	(37,783)	(35,749)	(114,081)	(101,853)
Recoveries	10,584	9,369	37,261	32,355
Other				(3,291)
Balance, end of period	195,582	171,516	195,582	171,516
Current unpaid balance - off-balance sheet retail motorcycle finance receivables	165,169	262,583	165,169	262,583	$ 236,706
Current unpaid balance - on-balance sheet retail motorcycle finance receivables	6,185,144	6,017,065	6,185,144	6,017,065	$ 5,839,467
Variable Interest Entity, Not Primary Beneficiary
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Principal balance of finance receivable		301,800		301,800
Variable Interest Entity, Not Primary Beneficiary | Asset-backed securitization debt
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Principal balance of finance receivable		301,800		301,800
Retail
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	185,899	152,998	166,810	139,320
Provision for credit losses	30,964	38,143	99,674	98,230
Charge-offs	(37,783)	(35,749)	(114,081)	(101,853)
Recoveries	10,584	9,369	37,261	32,355
Other				(3,291)
Balance, end of period	189,664	164,761	189,664	164,761
Wholesale
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Balance, beginning of period	7,629	8,355	6,533	7,858
Provision for credit losses	(1,711)	(1,600)	(615)	(1,103)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Other				0
Balance, end of period	$ 5,918	$ 6,755	$ 5,918	$ 6,755