Debt (Debt With A Contractual Term Greater Than One Year) (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Dec. 31, 2017	Sep. 24, 2017
Debt Instrument
Gross long-term debt	$ 5,722,673	$ 5,714,527	$ 6,138,192
Less: current portion of long-term debt, net of unamortized discount and debt issuance costs	(1,526,156)	(1,127,269)	(1,530,401)
Long-term debt, net	4,196,517	4,587,258	4,607,791
Secured Debt
Debt Instrument
Less: unamortized discount and debt issuance costs	(103)	(461)	(624)
Gross long-term debt	542,936	806,860	832,271
Secured Debt \| Asset-backed Canadian commercial paper conduit facility
Debt Instrument
Long-term debt, gross	149,418	174,779	122,130
Secured Debt \| Asset-Backed U.S. Commercial Paper Conduit Facility VIE
Debt Instrument
Long-term debt, gross	265,044	279,457	280,308
Secured Debt \| Asset-backed securitization debt
Debt Instrument
Long-term debt, gross	128,577	353,085	430,457
Unsecured Debt
Debt Instrument
Less: unamortized discount and debt issuance costs	(20,263)	(19,821)	(21,567)
Unsecured Debt \| 1.55% Medium-term notes due in 2017, issued November 2014
Debt Instrument
Long-term debt, gross	$ 0	$ 0	$ 400,000
Debt instrument, stated percentage	1.55%	1.55%	1.55%
Unsecured Debt \| 6.80% Medium-term notes due in 2018, issued May 2008
Debt Instrument
Long-term debt, gross	$ 0	$ 877,488	$ 877,488
Debt instrument, stated percentage	6.80%	6.80%	6.80%
Unsecured Debt \| 2.25% Medium-term notes due in 2019, issued January 2016
Debt Instrument
Long-term debt, gross	$ 600,000	$ 600,000	$ 600,000
Debt instrument, stated percentage	2.25%	2.25%	2.25%
Unsecured Debt \| Floating-Rate Medium Term Notes due 2019
Debt Instrument
Long-term debt, gross	$ 150,000	$ 150,000	$ 150,000
Unsecured Debt \| Two Point Four Percent Medium-Term Notes Due 2019
Debt Instrument
Long-term debt, gross	$ 600,000	$ 600,000	$ 600,000
Debt instrument, stated percentage	2.40%	2.40%	2.40%
Unsecured Debt \| 2.15% Medium-term notes due in 2020, issued February 2015
Debt Instrument
Long-term debt, gross	$ 600,000	$ 600,000	$ 600,000
Debt instrument, stated percentage	2.15%	2.15%	2.15%
Unsecured Debt \| Floating Rate Medium Term Notes due 2020
Debt Instrument
Long-term debt, gross	$ 450,000	$ 0	$ 0
Unsecured Debt \| Two Point Four Percent Medium-Term Notes Due 2020
Debt Instrument
Long-term debt, gross	$ 350,000	$ 350,000	$ 350,000
Debt instrument, stated percentage	2.40%	2.40%	2.40%
Unsecured Debt \| Two Point Eighty-five Percent Medium-Term Notes Due 2021
Debt Instrument
Long-term debt, gross	$ 600,000	$ 600,000	$ 600,000
Debt instrument, stated percentage	2.85%	2.85%	2.85%
Unsecured Debt \| Three Point Fifty-five Percent Medium-Term Notes due 2021
Debt Instrument
Long-term debt, gross	$ 350,000	$ 0	$ 0
Debt instrument, stated percentage	3.55%	3.55%	3.55%
Unsecured Debt \| Two Point Fifty-five Percent Medium-Term Notes Due 2022
Debt Instrument
Long-term debt, gross	$ 400,000	$ 400,000	$ 400,000
Debt instrument, stated percentage	2.55%	2.55%	2.55%
Unsecured Debt \| Three Point Thirty-five Percent Medium Term Notes Due 2023
Debt Instrument
Long-term debt, gross	$ 350,000	$ 0	$ 0
Debt instrument, stated percentage	3.35%	3.35%	3.35%
Unsecured Debt \| Three Point Five Percent Senior Unsecured Notes Due 2025
Debt Instrument
Long-term debt, gross	$ 450,000	$ 450,000	$ 450,000
Debt instrument, stated percentage	3.50%	3.50%	3.50%
Unsecured Debt \| Four Point Six Two Five Percent Senior Unsecured Notes Due 2045
Debt Instrument
Long-term debt, gross	$ 300,000	$ 300,000	$ 300,000
Debt instrument, stated percentage	4.625%	4.625%	4.625%
London Interbank Offered Rate (LIBOR) \| Unsecured Debt \| Floating-Rate Medium Term Notes due 2019
Debt Instrument
Debt instrument, basis spread on floating rate	0.35%
London Interbank Offered Rate (LIBOR) \| Unsecured Debt \| Floating Rate Medium Term Notes due 2020
Debt Instrument
Debt instrument, basis spread on floating rate	0.50%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

+ Details

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

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