Asset-Backed Financing (Assets And Liabilities Of Variable Interest Entities) (Detail) - USD ($) $ in Thousands	Jul. 01, 2018	Dec. 31, 2017	Jun. 25, 2017
Finance receivables
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	$ 741,938	$ 943,522	$ 1,050,702
Finance receivables | Asset-backed securitizations | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	229,201	439,301	599,754
Finance receivables | Asset-backed U.S. commercial paper conduit facilities | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	319,758	300,530	298,700
Finance receivables | Asset-backed Canadian commercial paper conduit facility | Variable Interest Entity, Not Primary Beneficiary
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	192,979	203,691	152,248
Allowance for credit losses
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	(20,058)	(26,824)	(30,334)
Allowance for credit losses | Asset-backed securitizations | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	(6,943)	(13,686)	(18,291)
Allowance for credit losses | Asset-backed U.S. commercial paper conduit facilities | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	(9,710)	(9,392)	(9,132)
Allowance for credit losses | Asset-backed Canadian commercial paper conduit facility | Variable Interest Entity, Not Primary Beneficiary
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	(3,405)	(3,746)	(2,911)
Restricted cash
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	50,933	58,689	74,395
Restricted cash | Asset-backed securitizations | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	21,912	34,919	47,980
Restricted cash | Asset-backed U.S. commercial paper conduit facilities | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	17,845	13,787	14,993
Restricted cash | Asset-backed Canadian commercial paper conduit facility | Variable Interest Entity, Not Primary Beneficiary
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	11,176	9,983	11,422
Other assets
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	1,554	2,618	2,373
Other assets | Asset-backed securitizations | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	465	1,260	1,360
Other assets | Asset-backed U.S. commercial paper conduit facilities | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	815	888	810
Other assets | Asset-backed Canadian commercial paper conduit facility | Variable Interest Entity, Not Primary Beneficiary
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	274	470	203
Total assets
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	774,367	978,005	1,097,136
Total assets | Asset-backed securitizations | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	244,635	461,794	630,803
Total assets | Asset-backed U.S. commercial paper conduit facilities | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	328,708	305,813	305,371
Total assets | Asset-backed Canadian commercial paper conduit facility | Variable Interest Entity, Not Primary Beneficiary
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	201,024	210,398	160,962
Asset-backed debt
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, associated liabilities, carrying amount	636,068	806,860	939,872
Asset-backed debt | Asset-backed securitizations | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, associated liabilities, carrying amount	169,430	352,624	521,300
Asset-backed debt | Asset-backed U.S. commercial paper conduit facilities | SPEs
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, associated liabilities, carrying amount	300,000	279,457	279,833
Asset-backed debt | Asset-backed Canadian commercial paper conduit facility | Variable Interest Entity, Not Primary Beneficiary
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, associated liabilities, carrying amount	$ 166,638	$ 174,779	$ 138,739