Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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(19)(a)(3))
-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(a)(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(13)(2))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 835
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

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

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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.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Debt Obligations and Commitments - Additional Information (Detail) CAD in Millions, $ in Millions	6 Months Ended
	Jun. 17, 2017 USD ($)	Jun. 17, 2017 CAD	Jun. 06, 2016 USD ($)
Debt Instrument [Line Items]
Repayments of Debt	$ 1,000.0
Commercial Paper	1,800.0
Notes Due 2019 [Member] \| Variable Income Interest Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	350.0
Notes Due 2019 [Member] \| One Point Five Five Zero Percent Notes Due 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	750.0
Notes Due 2022 [Member] \| Variable Income Interest Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	400.0
Notes Due 2022 [Member] \| Two Point Two Five Zero Percent Notes Due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 750.0
Two Point One Five Zero Percent Notes Due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.15%	2.15%
Four Point Zero Percent Notes Due 2047 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.00%	4.00%
Notes Due 2047 [Member] \| Four Point Zero Percent Notes Due 2047 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 750.0
Two Point Two Five Zero Percent Notes Due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.25%	2.25%
One Point Five Five Zero Percent Notes Due 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.55%	1.55%
Five-Year Unsecured Revolving Credit Agreement (Five-Year Credit Agreement) [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 3,750.0		$ 3,722.5
Line of Credit Facility, Maximum Borrowing Capacity	4,500.0
Notes Due 2024 [Member] \| Two Point One Five Zero Percent Notes Due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount \| CAD		CAD 750
364-Day Unsecured Revolving Credit Agreement (364-Day Credit Agreement) [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity	3,750.0		$ 3,722.5
Line of Credit Facility, Maximum Borrowing Capacity	$ 4,500.0