Fair Value (Summary of Assets And Liabilities Measured at Fair Value) (Detail) - USD ($) $ in Thousands	Jul. 01, 2018	Dec. 31, 2017	Jun. 25, 2017
Fair Value, Measurements, Recurring
Assets:
Cash equivalents	$ 691,983	$ 488,432	$ 625,485
Marketable securities	49,537	48,006	44,156
Derivatives	13,446	1,769	458
Assets, fair value	754,966	538,207	670,099
Liabilities:
Derivatives, liabilities	625	21,308	4,865
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Cash equivalents	446,454	358,500	375,550
Marketable securities	49,537	48,006	44,156
Derivatives	0	0	0
Assets, fair value	495,991	406,506	419,706
Liabilities:
Derivatives, liabilities	0	0	0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Assets:
Cash equivalents	245,529	129,932	249,935
Marketable securities	0	0	0
Derivatives	13,446	1,769	458
Assets, fair value	258,975	131,701	250,393
Liabilities:
Derivatives, liabilities	625	21,308	4,865
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Assets:
Cash equivalents	0	0	0
Marketable securities	0	0	0
Derivatives	0	0	0
Assets, fair value	0	0	0
Liabilities:
Derivatives, liabilities	0	0	0
Fair Value, Measurements, Nonrecurring | Fair Value Adjustment
Liabilities:
Repossessed inventory	2,800	9,000	2,700
Fair Value, Measurements, Nonrecurring | Significant Other Observable Inputs (Level 2) | Fair Value
Liabilities:
Repossessed inventory	$ 16,400	$ 19,600	$ 17,900