Finance Receivables (Allowance For Credit Losses And Finance Receivables By Portfolio Individually And Collectively Evaluated For Impairment) (Detail) - USD ($)	Sep. 24, 2017	Jun. 25, 2017	Dec. 31, 2016	Sep. 25, 2016	Jun. 26, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	$ 0		$ 0	$ 0
Collectively evaluated for impairment	195,582,000		173,343,000	171,516,000
Total allowance for credit losses	195,582,000	$ 193,528,000	173,343,000	171,516,000	$ 161,353,000	$ 147,178,000
Individually evaluated for impairment	0		0	0
Collectively evaluated for impairment	7,296,607,000		7,008,801,000	7,321,482,000
Financing receivable, gross	7,296,607,000		7,008,801,000	7,321,482,000
Retail
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	0		0	0
Collectively evaluated for impairment	189,664,000		166,810,000	164,761,000
Total allowance for credit losses	189,664,000	185,899,000	166,810,000	164,761,000	152,998,000	139,320,000
Individually evaluated for impairment	0		0	0
Collectively evaluated for impairment	6,336,447,000		5,982,211,000	6,165,999,000
Financing receivable, gross	6,336,447,000		5,982,211,000	6,165,999,000
Wholesale
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	0		0	0
Collectively evaluated for impairment	5,918,000		6,533,000	6,755,000
Total allowance for credit losses	5,918,000	$ 7,629,000	6,533,000	6,755,000	$ 8,355,000	$ 7,858,000
Individually evaluated for impairment	0		0	0
Collectively evaluated for impairment	960,160,000		1,026,590,000	1,155,483,000
Financing receivable, gross	$ 960,160,000		$ 1,026,590,000	$ 1,155,483,000