Finance Receivables (Aging Of Past Due Finance Receivables Including Non Accrual Status Finance Receivables) (Detail) - USD ($) $ in Thousands	Sep. 24, 2017	Dec. 31, 2016	Sep. 25, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 205,181	$ 222,988	$ 193,757
Total finance receivables	7,296,607	7,008,801	7,321,482
Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, current	7,091,426	6,785,813	7,127,725
31-60 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	127,034	132,302	120,075
61-90 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	44,178	49,961	41,980
Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	33,969	40,725	31,702
Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	203,450	221,393	192,891
Total finance receivables	6,336,447	5,982,211	6,165,999
Retail | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, current	6,132,997	5,760,818	5,973,108
Retail | 31-60 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	126,705	131,302	119,709
Retail | 61-90 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	44,083	49,642	41,866
Retail | Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	32,662	40,449	31,316
Wholesale
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,731	1,595	866
Total finance receivables	960,160	1,026,590	1,155,483
Wholesale | Current
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, current	958,429	1,024,995	1,154,617
Wholesale | 31-60 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	329	1,000	366
Wholesale | 61-90 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	95	319	114
Wholesale | Greater than 90 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 1,307	$ 276	$ 386