Canadian Pacific Railway Limited (CP) 10-K 16 Feb 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 14, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Trading Symbol	CP
Entity Registrant Name	CANADIAN PACIFIC RAILWAY LTD/CN
Entity Central Index Key	16,875
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Current Reporting Status	Yes
Entity Common Stock, Shares Outstanding		144,212,716
Entity Public Float			$ 23,490,374,139
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - CAD shares in Millions, CAD in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues
Freight									CAD 6,375	CAD 6,060	CAD 6,552
Non-freight									179	172	160
Total revenues	CAD 1,713	CAD 1,595	CAD 1,643	CAD 1,603	CAD 1,637	CAD 1,554	CAD 1,450	CAD 1,591	6,554	6,232	6,712
Operating expenses
Compensation and benefits									1,035	1,189	1,371
Fuel									677	567	708
Materials									190	180	184
Equipment rents									142	173	174
Depreciation and amortization									661	640	595
Purchased Services and Other									1,056	905	1,060
Gain on sale of Delaware & Hudson South									0	0	(68)
Total operating expenses									3,761	3,654	4,024
Operating income	753	690	679	671	717	657	551	653	2,793	2,578	2,688
Less:
Other income and charges									(178)	(45)	335
Net interest expense									473	471	394
Income before income tax expense									2,498	2,152	1,959
Income tax expense									93	553	607
Net income	CAD 984	CAD 510	CAD 480	CAD 431	CAD 384	CAD 347	CAD 328	CAD 540	CAD 2,405	CAD 1,599	CAD 1,352
Earnings per share
Basic earnings per share	CAD 6.79	CAD 3.50	CAD 3.28	CAD 2.94	CAD 2.63	CAD 2.35	CAD 2.16	CAD 3.53	CAD 16.49	CAD 10.69	CAD 8.47
Diluted earnings per share	CAD 6.77	CAD 3.50	CAD 3.27	CAD 2.93	CAD 2.61	CAD 2.34	CAD 2.15	CAD 3.51	CAD 16.44	CAD 10.63	CAD 8.40
Weighted-average number of shares (millions)
Basic									145.9	149.6	159.7
Diluted									146.3	150.5	161

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - CAD CAD in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	CAD 984	CAD 510	CAD 480	CAD 431	CAD 384	CAD 347	CAD 328	CAD 540	CAD 2,405	CAD 1,599	CAD 1,352
Net gain (loss) in foreign currency translation adjustments, net of hedging activities									24	18	(86)
Change in derivatives designated as cash flow hedges									19	(2)	(69)
Change in pension and post-retirement defined benefit plans									80	(434)	1,059
Other comprehensive income (loss) before income taxes									123	(418)	904
Income tax (expense) recovery on above items									(65)	96	(162)
Other comprehensive income (loss)									58	(322)	742
Comprehensive income									CAD 2,463	CAD 1,277	CAD 2,094

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	CAD 338	CAD 164
Accounts receivable, net	687	591
Materials and supplies	152	184
Other current assets	97	70
Total current assets	1,274	1,009
Investments	182	194
Properties	17,016	16,689
Goodwill and intangible assets	187	202	CAD 211
Pension asset	1,407	1,070
Other assets	69	57
Total assets	20,135	19,221
Current liabilities
Accounts payable and accrued liabilities	1,238	1,322
Long-term debt maturing within one year	746	25
Total current liabilities	1,984	1,347
Pension and other benefit liabilities	749	734
Other long-term liabilities	231	284
Long-term debt	7,413	8,659
Deferred income taxes	3,321	3,571
Total liabilities	13,698	14,595
Shareholders’ equity
Share capital	2,032	2,002
Additional paid-in capital	43	52
Accumulated other comprehensive loss	(1,741)	(1,799)	(1,477)
Retained earnings	6,103	4,371
Total Shareholders' equity	6,437	4,626	CAD 4,796	CAD 5,610
Total liabilities and shareholders’ equity	CAD 20,135	CAD 19,221

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - CAD / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Common stock, shares authorized without par value (shares)	Unlimited	Unlimited
Common stock, par value (in CAD per share)	CAD 0	CAD 0
Common stock, shares issued (shares)	144,900,000	146,300,000
Common stock, shares outstanding (shares)	144,900,000	146,300,000
First preferred stock, shares authorized (shares)	Unlimited	Unlimited
Second preferred stock, shares authorized (shares)	Unlimited	Unlimited
First preferred stock, shares outstanding (shares)	0	0
Second preferred stock, shares outstanding (shares)	0	0

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating activities
Net income	CAD 2,405	CAD 1,599	CAD 1,352
Reconciliation of net income to cash provided by operating activities:
Depreciation and amortization	661	640	595
Deferred income taxes	(210)	320	234
Pension funding in excess of expense	(237)	(138)	(49)
Foreign exchange (gain) loss on long-term debt	(186)	(79)	297
Other operating activities, net	(113)	(198)	(245)
Change in non-cash working capital balances related to operations	(138)	(55)	275
Cash provided by operating activities	2,182	2,089	2,459
Investing activities
Additions to properties	(1,340)	(1,182)	(1,522)
Proceeds from the sale of property, plant and equipment	0	0	281
Proceeds from sale of properties and other assets	42	116	114
Other	3	(3)	4
Cash used in investing activities	(1,295)	(1,069)	(1,123)
Financing activities
Dividends paid	(310)	(255)	(226)
Issuance of CP Common Shares	45	21	43
Purchase of CP Common shares	(381)	(1,210)	(2,787)
Issuance of long-term debt, excluding commercial paper	0	0	3,411
Repayment of long-term debt, excluding commercial paper	(32)	(38)	(505)
Net repayment of commercial paper	0	(8)	(893)
Settlement of forward starting swaps	(22)	0	0
Other	0	(3)	0
Cash used in financing activities	(700)	(1,493)	(957)
Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents	(13)	(13)	45
Cash position
Increase (decrease) in cash and cash equivalents	174	(486)	424
Cash and cash equivalents at beginning of year	164	650	226
Cash and cash equivalents at end of year	338	164	650
Supplemental disclosures of cash flow information:
Income taxes paid	425	322	176
Interest paid	CAD 475	CAD 488	CAD 336

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - CAD CAD in Millions	Total	Share capital [Member]	Additional paid-in capital [Member]	Accumulated other comprehensive loss [Member]	Retained earnings [Member]
Beginning Balance at Dec. 31, 2014	CAD 5,610	CAD 2,185	CAD 36	CAD (2,219)	CAD 5,608
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,352	0	0	0	1,352
Other comprehensive income (loss)	742	0	0	742	0
Dividends declared	(221)	0	0	0	(221)
Effect of stock-based compensation expense	17	0	17	0	0
CP Common Shares repurchased	(2,748)	(181)	0	0	(2,567)
Stock issued under stock option plan	44	54	(10)	0	0
Ending Balance at Dec. 31, 2015	4,796	2,058	43	(1,477)	4,172
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,599	0	0	0	1,599
Other comprehensive income (loss)	(322)	0	0	(322)	0
Dividends declared	(274)	0	0	0	(274)
Effect of stock-based compensation expense	14	0	14	0	0
CP Common Shares repurchased	(1,210)	(84)	0	0	(1,126)
Stock issued under stock option plan	23	28	(5)	0	0
Ending Balance at Dec. 31, 2016	4,626	2,002	52	(1,799)	4,371
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,405	0	0	0	2,405
Other comprehensive income (loss)	58	0	0	58	0
Dividends declared	(319)	0	0	0	(319)
Effect of stock-based compensation expense	3	0	3	0	0
CP Common Shares repurchased	(381)	(27)	0	0	(354)
Stock issued under stock option plan	45	57	(12)	0	0
Ending Balance at Dec. 31, 2017	CAD 6,437	CAD 2,032	CAD 43	CAD (1,741)	CAD 6,103

CONSOLIDATED STATEMENTS OF CHA8

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) - CAD / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Stockholders' Equity [Abstract]
Dividends declared per share (in CAD per share)	CAD 2.1875	CAD 1.8500	CAD 1.4000

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Nature of Operations	Canadian Pacific Railway Limited (“CPRL”), through its subsidiaries (collectively referred to as “CP” or “the Company”), operates a transcontinental railway in Canada and the United States ("U.S."). CP provides rail and intermodal transportation services over a network of approximately 12,500
Summary of Significant Accounting Policies	Summary of significant accounting policies Accounting principles generally accepted in the United States of America (“GAAP”) These Consolidated Financial Statements are expressed in Canadian dollars and have been prepared in accordance with GAAP. Principles of consolidation These Consolidated Financial Statements include the accounts of CP and all its subsidiaries. The Company’s investments in which it has significant influence are accounted for using the equity method. All intercompany accounts and transactions have been eliminated. Use of estimates The preparation of these Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of revenues and expenses during the year, the reported amounts of assets and liabilities, and the disclosure of contingent assets and liabilities at the date of the financial statements. Management regularly reviews its estimates, including those related to environmental liabilities, pensions and other benefits, depreciable lives of properties, deferred income tax assets and liabilities, as well as legal and personal injury liabilities based upon currently available information. Actual results could differ from these estimates. Principal subsidiaries The following list sets out CPRL’s principal railway operating subsidiaries, including the jurisdiction of incorporation. All of these subsidiaries are wholly owned, directly or indirectly, by CPRL as at December 31, 2017 . Principal subsidiary Incorporated under the laws of Canadian Pacific Railway Company Canada Soo Line Railroad Company (“Soo Line”) Minnesota Delaware and Hudson Railway Company, Inc. (“D&H”) Delaware Dakota, Minnesota & Eastern Railroad Corporation (“DM&E”) Delaware Mount Stephen Properties Inc. (“MSP”) Canada Revenue recognition Railway freight revenues are recognized based on the percentage of completed service method. The allocation of revenue between reporting periods is based on the relative transit time in each reporting period with expenses recognized as incurred. Volume rebates to customers are accrued as a reduction of freight revenues based on estimated volume and contract terms as freight service is provided. Other revenues, including passenger revenue, revenue from leasing certain assets, switching fees, and revenue from logistics services, are recognized as service is performed or contractual obligations are met. Revenues are presented net of taxes collected from customers and remitted to government authorities. Cash and cash equivalents Cash and cash equivalents include highly liquid short-term investments that are readily convertible to cash with original maturities of 3 months or less, but exclude cash and cash equivalents subject to restrictions. Restricted cash and cash equivalents Cash and cash equivalents that are restricted as to withdrawal or usage, in accordance with specific agreements, are presented as restricted cash and cash equivalents on the balance sheets when applicable. In the Consolidated Statements of Cash Flow, these balances, if any, are included with cash and cash equivalents. Foreign currency translation Assets and liabilities denominated in foreign currencies, other than those held through foreign subsidiaries, are translated into Canadian dollars at the year-end exchange rate for monetary items and at the historical exchange rates for non-monetary items. Foreign currency revenues and expenses are translated at the exchange rates in effect on the dates of the related transactions. Foreign exchange ("FX") gains and losses, other than those arising from the translation of the Company’s net investment in foreign subsidiaries, are included in income. The accounts of the Company’s foreign subsidiaries are translated into Canadian dollars using the year-end exchange rate for assets and liabilities and the average exchange rates during the year for revenues, expenses, gains and losses. FX gains and losses arising from the translation of the foreign subsidiaries’ assets and liabilities are included in “Other comprehensive income (loss)”. A portion of U.S. dollar-denominated long-term debt has been designated as a hedge of the net investment in foreign subsidiaries. As a result, unrealized FX gains and losses on U.S. dollar-denominated long-term debt, designated as a hedge, are offset against FX gains and losses arising from the translation of foreign subsidiaries’ accounts in “Other comprehensive income (loss)”. Pensions and other benefits Pension costs are actuarially determined using the projected-benefit method pro-rated over the credited service periods of employees. This method incorporates management’s best estimates of expected plan investment performance, salary escalation and retirement ages of employees. The expected return on fund assets is calculated using market-related asset values developed from a five-year average of market values for the fund’s public equity securities and absolute return strategies (with each prior year’s market value adjusted to the current date for assumed investment income during the intervening period) plus the market value of the fund’s fixed income, real estate and infrastructure securities, subject to the market-related asset value not being greater than 120% of the market value nor being less than 80% of the market value. The discount rate used to determine the projected-benefit obligation is based on blended market interest rates on high-quality corporate debt instruments with matching cash flows. Unrecognized actuarial gains and losses in excess of 10% of the greater of the benefit obligation and the market-related value of plan assets are amortized over the expected average remaining service period of active employees expected to receive benefits under the plan (approximately 12 years). Prior service costs arising from collectively bargained amendments to pension plan benefit provisions are amortized over the term of the applicable union agreement. Prior service costs arising from all other sources are amortized over the expected average remaining service period of active employees who are expected to receive benefits under the plan at the date of amendment. Costs for post-retirement and post-employment benefits other than pensions, including post-retirement health care and life insurance and some workers’ compensation and long-term disability benefits in Canada, are actuarially determined on a basis similar to pension costs. The over or under funded status of defined benefit pension and other post-retirement benefit plans are measured as the difference between the fair value of the plan assets and the benefit obligation, and are recognized on the balance sheets. In addition, any unrecognized actuarial gains and losses and prior service costs and credits that arise during the period are recognized as a component of “Other comprehensive income (loss)”, net of tax. Gains and losses on post-employment benefits that do not vest or accumulate, including some workers’ compensation and long-term disability benefits in Canada, are included immediately in income as “Compensation and benefits”. Materials and supplies Materials and supplies are carried at the lower of average cost or market value and consist primarily of fuel and parts used in the repair and maintenance of track structures, equipment, locomotives and freight cars. Properties Fixed asset additions and major renewals are recorded at cost, including direct costs, attributable indirect costs and carrying costs, less accumulated depreciation and any impairment. When there is a legal obligation associated with the retirement of property, a liability is initially recognized at its fair value and a corresponding asset retirement cost is added to the gross book value of the related asset and amortized to expense over the estimated term to retirement. The Company reviews the carrying amounts of its properties whenever changes in circumstances indicate that such carrying amounts may not be recoverable based on future undiscounted cash flows. When such properties are determined to be impaired, recorded asset values are revised to their fair value and an impairment loss is recognized. The Company recognizes expenditures as additions to properties or operating expenses based on whether the expenditures increase the output or service capacity, lower the associated operating costs or extend the useful life of the properties and whether the expenditures exceed minimum physical and financial thresholds. Much of the additions to properties, both new and replacement properties, are self-constructed. These are initially recorded at cost, including direct costs and attributable indirect costs, overheads and carrying costs. Direct costs include, among other things, labour costs, purchased services, equipment costs and material costs. Attributable indirect costs and overheads include incremental long-term variable costs resulting from the execution of capital projects. Indirect costs mainly include work trains, material distribution, highway vehicles and work equipment. Overheads primarily include a portion of the engineering department’s costs, which plans, designs and administers these capital projects. These costs are allocated to projects by applying a measure consistent with the nature of the cost, based on cost studies. For replacement properties, the project costs are allocated to dismantling and installation based on cost studies. Dismantling work is performed concurrently with the installation. Ballast programs including undercutting, shoulder ballasting and renewal programs that form part of the annual track program are capitalized as this work, and the related added ballast material, significantly improves drainage, which in turn extends the life of ties and other track materials. These costs are tracked separately from the underlying assets and depreciated over the period to the next estimated similar ballast program. Spot replacement of ballast is considered a repair which is expensed as incurred. The costs of large refurbishments are capitalized and locomotive overhauls are expensed as incurred, except where overhauls represent a betterment of the locomotive in which case costs are capitalized. The Company capitalizes development costs for major new computer systems. The Company follows group depreciation, which groups assets which are similar in nature and have similar economic lives. The property groups are depreciated on a straight-line basis reflecting their expected economic lives determined by depreciation studies. Depreciation studies are regular reviews of asset service lives, salvage values, accumulated depreciation and other related factors. Depreciation rates are established through these studies. Actual use and retirement of assets may vary from current estimates, and would be identified in the next study. These changes in expected economic lives would impact the amount of depreciation expense recognized in future periods. All track assets are depreciated using a straight-line method which recognizes the value of the asset consumed as a percentage of the whole life of the asset. When depreciable property is retired or otherwise disposed of in the normal course of business, the book value, less net salvage proceeds, is charged to accumulated depreciation and if different than the assumptions under the depreciation study could potentially result in adjusted depreciation expense over a period of years. However, when removal costs exceed the salvage value on assets and the Company has no legal obligation to remove the assets, the removal costs incurred are charged to income in the period in which the assets are removed and are not charged to accumulated depreciation. For certain asset classes, the historical cost of the asset is separately recorded in the Company’s property records. This amount is retired from the property records upon retirement of the asset. For assets for which the historical cost cannot be separately identified the amount of the gross book value to be retired is estimated using either an indexation methodology, whereby the current replacement cost of the asset is indexed to the estimated year of installation for the asset, or a first-in, first-out approach, or statistical analysis is used to determine the age of the retired asset. CP uses indices that closely correlate to the principal costs of the assets. There are a number of estimates inherent in the depreciation and retirement processes and as it is not possible to precisely estimate each of these variables until a group of property is completely retired, CP regularly monitors the estimated service lives of assets and the associated accumulated depreciation for each asset class to ensure depreciation rates are appropriate. If the recorded amounts of accumulated depreciation are greater or less than the amounts indicated by the depreciation studies then the excess or deficit is amortized as a component of depreciation expense over the remaining service lives of the applicable asset classes. For the sale or retirement of larger groups of depreciable assets that are unusual and were not considered in the Company’s depreciation studies, CP records a gain or loss for the difference between net proceeds and net book value of the assets sold or retired. The accumulated depreciation to be retired includes asset-specific accumulated depreciation, when known, and an appropriate portion of the accumulated depreciation recorded for the relevant asset class as a whole, calculated using a cost-based allocation. Revisions to the estimated useful lives and net salvage projections constitute a change in accounting estimate and are addressed prospectively by amending depreciation rates. Equipment under capital lease is included in Properties and depreciated over the period of expected use. Assets held for sale Assets to be disposed that meet the held for sale criteria are reported at the lower of their carrying amount and fair value, less costs to sell, and are no longer depreciated. Goodwill and intangible assets Goodwill represents the excess of the purchase price over the fair value of identifiable net assets upon acquisition of a business. Goodwill is assigned to the reporting units that are expected to benefit from the business acquisition which, after integration of operations with the railway network, may be different than the acquired business. The carrying value of goodwill, which is not amortized, is assessed for impairment annually in the fourth quarter of each year as at October 1st, or more frequently as economic events dictate. The Company has the option of performing an assessment of certain qualitative factors (“Step 0”) to determine if it is more likely than not that the fair value of a reporting unit is less than its carrying value or proceeding directly to a quantitative impairment test (“Step 1”). Qualitative factors include but are not limited to, economic, market and industry conditions, cost factors and overall financial performance of the reporting unit. If Step 0 indicates that the carrying value is less than the fair value, then performing the two-step impairment test is unnecessary. Under Step 1, the fair value of the reporting unit is compared to its carrying value, including goodwill. If the fair value of the reporting unit is less than its carrying value, goodwill is potentially impaired. The impairment charge that would be recognized is the excess of the carrying value of the goodwill over the fair value of the goodwill, determined in the same manner as in a business combination. Intangible assets with finite lives are amortized on a straight-line basis over the estimated useful lives of the respective assets. Favourable leases, customer relationships and interline contracts have amortization periods ranging from 15 to 20 years. When there is a change in the estimated useful life of an intangible asset with a finite life, amortization is adjusted prospectively. Financial instruments Financial instruments are contracts that give rise to a financial asset of one party and a financial liability or equity instrument of another party. Financial instruments are recognized initially at fair value, which is the amount of consideration that would be agreed upon in an arm’s-length transaction between willing parties. Subsequent measurement depends on how the financial instruments have been classified. Accounts receivable and investments, classified as loans and receivables, are measured at amortized cost, using the effective interest method. Cash and cash equivalents and derivatives are classified as held for trading and are measured at fair value. Accounts payable, accrued liabilities, short-term borrowings, dividends payable, other long-term liabilities and long-term debt, classified as other liabilities, are also measured at amortized cost. Derivative financial instruments Derivative financial and commodity instruments may be used from time to time by the Company to manage its exposure to risks relating to foreign currency exchange rates, stock-based compensation, interest rates and fuel prices. When CP utilizes derivative instruments in hedging relationships, CP identifies, designates and documents those hedging transactions and regularly tests the transactions to demonstrate effectiveness in order to continue hedge accounting. All derivative instruments are classified as held for trading and recorded at fair value. Any change in the fair value of derivatives not designated as hedges is recognized in the period in which the change occurs in the Consolidated Statements of Income in the line item to which the derivative instrument is related. On the Consolidated Balance Sheets they are classified in “Other assets”, “Other long-term liabilities”, “Other current assets” or “Accounts payable and accrued liabilities” as applicable. Gains and losses arising from derivative instruments may affect the following lines on the Consolidated Statements of Income: “Revenues”, “Compensation and benefits”, “Fuel”, “Other income and charges”, and “Net interest expense”. For fair value hedges, the periodic changes in values are recognized in income, on the same line as the changes in values of the hedged items are also recorded. For a cash flow hedge, the change in value of the effective portion is recognized in “Other comprehensive income (loss)”. Any ineffectiveness within an effective cash flow hedge is recognized in income as it arises in the same income account as the hedged item. Should a cash flow hedging relationship become ineffective, previously unrealized gains and losses remain within “Accumulated other comprehensive loss” until the hedged item is settled and, prospectively, future changes in value of the derivative are recognized in income. The change in value of the effective portion of a cash flow hedge remains in “Accumulated other comprehensive loss” until the related hedged item settles, at which time amounts recognized in “Accumulated other comprehensive loss” are reclassified to the same income or balance sheet account that records the hedged item. In the Consolidated Statements of Cash Flows, cash flows relating to derivative instruments designated as hedges are included in the same line as the related hedged items. Environmental remediation Environmental remediation accruals, recorded on an undiscounted basis unless a reliably determinable estimate as to amount and timing of costs can be established, cover site-specific remediation programs. The accruals are recorded when the costs to remediate are probable and reasonably estimable. Certain future costs to monitor sites are discounted at an adjusted risk-free rate. Provisions for environmental remediation costs are recorded in “Other long-term liabilities”, except for the current portion, which is recorded in “Accounts payable and accrued liabilities”. Income taxes The Company follows the liability method of accounting for income taxes. Deferred income tax assets and liabilities are determined based on differences between the financial reporting and tax bases of assets and liabilities using enacted tax rates and laws that will be in effect when the differences are expected to reverse. The effect of a change in income tax rates on deferred income tax assets and liabilities is recognized in income in the period during which the change occurs. When appropriate, the Company records a valuation allowance against deferred tax assets to reflect that these tax assets may not be realized. In determining whether a valuation allowance is appropriate, CP considers whether it is more likely than not that all or some portion of CP’s deferred tax assets will not be realized, based on management’s judgment using available evidence about future events. At times, tax benefit claims may be challenged by a tax authority. Tax benefits are recognized only for tax positions that are more likely than not sustainable upon examination by tax authorities. The amount recognized is measured as the largest amount of benefit that is greater than 50% likely to be realized upon settlement. A liability for “unrecognized tax benefits” is recorded for any tax benefits claimed in CP’s tax returns that do not meet these recognition and measurement standards. Investment and other similar tax credits are deferred on the Consolidated Balance Sheets and amortized to “Income tax expense” as the related asset is recognized in income. Earnings per share Basic earnings per share are calculated using the weighted average number of common shares outstanding during the year. Diluted earnings per share are calculated using the treasury stock method for determining the dilutive effect of options. Stock-based compensation CP follows the fair value based approach to account for stock options. Compensation expense and an increase in “Additional paid-in capital” are recognized for stock options over their vesting period, or over the period from the grant date to the date employees become eligible to retire when this is shorter than the vesting period, based on their estimated fair values on the grant date, as determined using the Black-Scholes option-pricing model. Any consideration paid by employees on exercise of stock options is credited to “Share capital” when the option is exercised and the recorded fair value of the option is removed from “Additional paid-in capital" and credited to “Share capital”. Compensation expense is also recognized for deferred share units (“DSUs”), performance share units (“PSUs”) and restricted share units (“RSUs”) using the fair value method. Compensation expense is recognized over the vesting period, or for PSUs and DSUs only, over the period from the grant date to the date employees become eligible to retire when this is shorter than the vesting period. Forfeitures of DSUs, PSUs and RSUs are estimated at issuance and subsequently at the balance sheet date.

Accounting Changes

Accounting Changes	12 Months Ended
	Dec. 31, 2017
Accounting Changes and Error Corrections [Abstract]
Accounting Changes	Accounting changes Implemented in 2017 Compensation – Stock Compensation In March 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update (“ASU”) 2016-09, Improvements to Employee Share-based Payment Accounting, under FASB Accounting Standards Codification ("ASC") Topic 718. The amendments clarify the guidance relating to treatment of excess tax benefits and deficiencies, acceptable forfeiture rate policies, and treatment of cash paid by an employer when directly withholding shares for tax-withholding purposes and the requirement to treat such cash flows as a financing activity. As a result of this ASU, excess tax benefits are no longer recorded in additional paid- in capital and instead are applied against taxes payable or recognized in the Consolidated Statement of Income. This ASU was effective for CP beginning on January 1, 2017. The Company has determined that there were no significant changes to disclosure, financial statement presentation, and no material changes to accounting as a result of adoption. Simplifying the Measurement of Inventory In July 2015, the FASB issued ASU 2015-11, Simplifying the Measurement of Inventory under FASB ASC Topic 330. The amendments require that reporting entities measure inventory at the lower of cost and net realizable value. Net realizable value is the estimated selling price in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The amendments apply to inventory that is measured using the first-in, first-out or average cost basis. This ASU was effective for CP beginning on January 1, 2017 and was applied prospectively. The Company determined there were no changes to disclosure, financial statement presentation, or valuation of inventory as a result of adoption. Future changes Revenue from Contracts with Customers In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers under FASB ASC Topic 606. The FASB has also issued several updates to ASU 2014-09. The guidance in Topic 606, as amended, will be effective for CP for interim and annual periods commencing January 1, 2018. CP will adopt the new standard by using the modified retrospective approach. CP has analyzed contracts and public tariffs for a significant proportion of the Company’s annual rail freight revenue, which represents greater than 95% of CP’s annual revenues, and has identified the distinct services provided to customers that represent performance obligations under contracts and public tariffs. CP has also assessed key contracts with customers that generate non-freight revenues. CP has concluded that recognizing rail freight revenues over time as performance obligations related to rail freight services are satisfied continues to be appropriate. Certain other services provided to customers are satisfied at a point in time and will continue to be recognized in this manner. CP has substantially completed its assessment of its revenues earned from contracts with customers and does not expect any significant adjustment to be required upon adoption of the standard. Additional disclosures will be provided in CP's first quarter 2018 financial statements. Compensation – Retirement Benefits In March 2017, the FASB issued ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Post-retirement Benefit Cost under FASB ASC Topic 715. The amendments clarify presentation requirements for net periodic pension cost and net periodic post-retirement benefit cost and require that an employer report the current service cost component in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net periodic benefit cost are required to be presented in the Consolidated Statement of Income separately from the current service cost component and outside a subtotal of income from operations. The amendments also restrict capitalization to the current service cost component when applicable. The amendments are effective for CP beginning on January 1, 2018. The amendments related to presentation are required to be applied retrospectively and the restrictions on capitalization of the current service cost component are applicable prospectively on the date of adoption. The impacts of the reclassification are detailed as follows: Year ended December 31 (in millions of Canadian dollars) 2017 2016 2015 Decrease in operating income $ 274 $ 167 $ 70 There will be no change to Net income or earnings per share as a result of adoption of this new standard. The new guidance restricting capitalization of pensions to the current service cost component of net periodic benefit cost will have no impact to operating income or amounts capitalized because the Company currently only capitalizes an appropriate portion of current service cost for self-constructed properties. CP is currently assessing the disclosure requirements of this ASU. Derivatives and Hedging In August 2017, the FASB issued Accounting Standards Update ASU 2017-12, Targeted Improvements to Accounting for Hedging Activities, under FASB ASC Topic 815. This is intended to improve the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities in its financial statements. These amendments also make targeted improvements to simplify the application of the hedge accounting guidance in current GAAP. The amendments require the entire change in the fair value of the hedging instrument to be recorded in other comprehensive income for effective cash flow hedges. Consequently, any ineffective portion of the change in fair value will, therefore, no longer be recorded to the Consolidated Statement of Income as it arises. The amendments are effective for CP beginning on January 1, 2019, although early adoption is permitted. Entities are required to apply the amendments in this update to hedging relationships existing on the date of adoption, reflected as a cumulative-effect adjustment as of the beginning of the fiscal year of adoption. Other amendments to presentation and disclosure are applied prospectively. The Company will early adopt this ASU effective January 1, 2018 and no significant cumulative-effect adjustment will be required. Leases In February 2016, the FASB issued ASU 2016-02, Leases under FASB ASC Topic 842. This new standard requires recognition of right-of-use assets and lease liabilities by lessees for those leases classified as finance and operating leases with a maximum term exceeding 12 months. For CP this new standard will be effective for interim and annual periods commencing January 1, 2019. Entities are required to use a modified retrospective approach to adopt this new standard. The Company has a detailed plan to implement the new standard and is assessing contractual arrangements, through a cross-functional team, that may qualify as leases under the new standard. CP is also working with a vendor to implement a lease management system which will assist in delivering the required accounting changes. CP's cross-functional team and the vendor finalized system requirements and developed work flows and testing scenarios that will permit system implementation and parallel testing in 2018 for CP's lease system solution. The impact of the new standard will be a material increase to right of use assets and lease liabilities on the Company's Consolidated Balance Sheets, primarily, as a result of operating leases currently not recognized on the balance sheet. The Company does not anticipate a material impact to Net income and is currently evaluating the impact adoption of this new standard will have on disclosure. Intangibles – Goodwill and Other

Other Income and Charges

Other Income and Charges	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
Other Income and Charges	Other income and charges (in millions of Canadian dollars) 2017 2016 2015 Foreign exchange (gain) loss on long-term debt $ (186 ) $ (79 ) $ 297 Other foreign exchange gains (7 ) (5 ) (24 ) Early redemption premium on notes (Note 16) — — 47 Insurance recovery of legal settlement (10 ) — — Legal settlement — 25 — Charge on hedge roll and de-designation 13 — — Other 12 14 15 Total other income and charges $ (178 ) $ (45 ) $ 335

Net Interest Expense

Net Interest Expense	12 Months Ended
	Dec. 31, 2017
Interest Income (Expense), Net [Abstract]
Net Interest Expense	Net interest expense (in millions of Canadian dollars) 2017 2016 2015 Interest cost $ 491 $ 497 $ 409 Interest capitalized to Properties (16 ) (25 ) (14 ) Interest expense 475 472 395 Interest income (2 ) (1 ) (1 ) Net interest expense $ 473 $ 471 $ 394 Interest expense includes interest on capital leases of $11 million for the year ended December 31, 2017 ( 2016 – $11 million ; 2015 – $11 million

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income taxes The following is a summary of the major components of the Company’s income tax expense: (in millions of Canadian dollars) 2017 2016 2015 Current income tax expense $ 303 $ 233 $ 373 Deferred income tax expense Origination and reversal of temporary differences 371 336 105 Effect of tax rate (decrease) increase (541 ) — 23 Effect of hedge of net investment in foreign subsidiaries (42 ) (20 ) 100 Other 2 4 6 Total deferred income tax (recovery) expense (210 ) 320 234 Total income taxes $ 93 $ 553 $ 607 Income before income tax expense Canada $ 1,829 $ 1,513 $ 1,099 Foreign 669 639 860 Total income before income tax expense $ 2,498 $ 2,152 $ 1,959 Income tax expense Current Canada $ 257 $ 165 $ 173 Foreign 46 68 200 Total current income tax expense 303 233 373 Deferred Canada 256 207 163 Foreign (466 ) 113 71 Total deferred income tax (recovery) expense (210 ) 320 234 Total income taxes $ 93 $ 553 $ 607 The provision for deferred income taxes arises from temporary differences in the carrying values of assets and liabilities for financial statement and income tax purposes and the effect of loss carry forwards. The items comprising the deferred income tax assets and liabilities are as follows: (in millions of Canadian dollars) 2017 2016 Deferred income tax assets Amount related to tax losses carried forward $ 12 $ 18 Liabilities carrying value in excess of tax basis 88 149 Environmental remediation costs 16 30 Other 11 58 Total deferred income tax assets 127 255 Deferred income tax liabilities Properties carrying value in excess of tax basis 3,181 3,796 Pensions carrying value in excess of tax basis (1) 226 — Other 41 30 Total deferred income tax liabilities 3,448 3,826 Total net deferred income tax liabilities $ 3,321 $ 3,571 (1) Balance previously included as part of "Liabilities carrying value in excess of tax basis" as a component of deferred income tax assets. The Company’s consolidated effective income tax rate differs from the expected Canadian statutory tax rates. Expected income tax expense at statutory rates is reconciled to income tax expense as follows: (in millions of Canadian dollars, except percentage) 2017 2016 2015 Statutory federal and provincial income tax rate (Canada) 26.56 % 26.65 % 26.47 % Expected income tax expense at Canadian enacted statutory tax rates $ 663 $ 573 $ 519 Increase (decrease) in taxes resulting from: (Gains) losses not subject to tax (27 ) (23 ) 28 Canadian tax rate differentials 1 — 1 Foreign tax rate differentials (9 ) — 39 Effect of tax rate (decrease) increase (541 ) — 23 Other 6 3 (3 ) Income tax expense $ 93 $ 553 $ 607 The Company has no unrecognized tax benefits from capital losses at December 31, 2017 and 2016 . On December 22, 2017, the U.S. enacted the “Tax Cuts and Jobs Act” which has been commonly referred to as U.S. tax reform. A significant change under this reform is the reduction of U.S. federal statutory corporate income tax rate from 35% to 21% beginning in 2018. As a result of this and other tax rate increases in the province of British Columbia and the state of Illinois, the Company revalued its deferred income tax balances accordingly. For the full year 2017, revaluations of deferred tax balances associated with changes in rates total a net recovery of $541 million (2016 – $ nil ). These recoveries are estimated based on the Company's analysis of the Tax Cuts and Jobs Act. These estimates may be impacted as U.S. authorities issue additional regulations and interpretations in the future. The Company has not provided a deferred liability for the income taxes, if any, which might become payable on any temporary difference associated with its foreign investments because the Company intends to indefinitely reinvest in its foreign investments and has no intention to realize this difference by a sale of its interest in foreign investments. It is not practical to calculate the amount of the deferred tax liability. At December 31, 2017 , the Company had income tax operating losses carried forward of $11 million , which have been recognized as a deferred tax asset. Certain of these losses carried forward will begin to expire in 2027, with the majority expiring between 2029 and 2035. The Company did no t have any minimum tax credits or investment tax credits carried forward. It is more likely than not that the Company will realize the majority of its deferred income tax assets from the generation of future taxable income, as the payments for provisions, reserves and accruals are made and losses and tax credits carried forward are utilized. The following table provides a reconciliation of uncertain tax positions in relation to unrecognized tax benefits for Canada and the U.S. for the year ended December 31, 2017 : (in millions of Canadian dollars) 2017 2016 2015 Unrecognized tax benefits at January 1 $ 13 $ 15 $ 17 Increase in unrecognized: Tax benefits related to the current year — — 4 Dispositions: Gross uncertain tax benefits related to prior years — (2 ) (6 ) Unrecognized tax benefits at December 31 $ 13 $ 13 $ 15 If these uncertain tax positions were recognized, all of the amount of unrecognized tax positions as at December 31, 2017 would impact the Company’s effective tax rate. The Company recognizes accrued interest and penalties related to unrecognized tax benefits as a component of income tax expense in the Company’s Consolidated Statements of Income. The total amount of accrued interest and penalties in 2017 was $1 million ( 2016 – $1 million ; 2015 – $4 million ). The total amount of accrued interest and penalties associated with the unrecognized tax benefit at December 31, 2017 was $11 million ( 2016 – $10 million ; 2015 – $9 million ). The Company and its subsidiaries are subject to either Canadian federal and provincial income tax, U.S. federal, state and local income tax, or the relevant income tax in other international jurisdictions. The Company has substantially concluded all Canadian federal and provincial income tax matters for the years through 2012. The federal and provincial income tax returns filed for 2013 and subsequent years remain subject to examination by the Canadian taxation authorities. The Internal Revenue Service ("IRS") of the United States has completed their examinations and issued notices of deficiency for the tax years 2012 and 2013. The Company disagrees with many of their proposed adjustments, and is at the IRS Appeals for those years. The income tax returns for 2014 and subsequent years continue to remain subject to examination by the IRS. Additionally, various U.S. state tax authorities are examining the Company's state income tax returns for the years 2011 through 2015. The Company believes that it has recorded sufficient income tax reserves at December 31, 2017 with respect to these income tax examinations. The Company does not anticipate any material changes to the unrecognized tax benefits previously disclosed within the next twelve months as at December 31, 2017

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Share	Earnings per share Basic earnings per share have been calculated using Net income for the year divided by the weighted average number of shares outstanding during the year. Diluted earnings per share have been calculated using the treasury stock method which assumes that any proceeds received from the exercise of in-the-money options would be used to purchase CP Common Shares at the average market price for the period. For purposes of this calculation, at December 31, 2017 , there were 1.4 million dilutive options outstanding ( 2016 – 2.2 million ; 2015 – 2.5 million ). The number of shares used and the earnings per share calculations are reconciled as follows: (in millions of Canadian dollars, except per share data) 2017 2016 2015 Net income $ 2,405 $ 1,599 $ 1,352 Weighted average basic shares outstanding (millions) 145.9 149.6 159.7 Dilutive effect of weighted average number of stock options (millions) 0.4 0.9 1.3 Weighted average diluted shares outstanding (millions) 146.3 150.5 161.0 Earnings per share – basic $ 16.49 $ 10.69 $ 8.47 Earnings per share – diluted $ 16.44 $ 10.63 $ 8.40 In 2017 , the number of options excluded from the computation of diluted earnings per share because their effect was not dilutive was 0.3 million ( 2016 – 0.4 million ; 2015 – 0.2 million

Other Comprehensive Income (Los

Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss	12 Months Ended
	Dec. 31, 2017
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss	Other comprehensive income (loss) and accumulated other comprehensive loss The components of Other comprehensive income (loss) and the related tax effects are as follows: (in millions of Canadian dollars) Before Income tax (expense) recovery Net of tax For the year ended December 31, 2017 Unrealized foreign exchange (loss) gain on: Translation of the net investment in U.S. subsidiaries $ (295 ) $ — $ (295 ) Translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries (Note 17) 319 (42 ) 277 Change in derivatives designated as cash flow hedges: Realized loss on cash flow hedges recognized in income 25 (6 ) 19 Unrealized loss on cash flow hedges (6 ) 2 (4 ) Change in pension and other benefits actuarial gains and losses 84 (20 ) 64 Change in prior service pension and other benefit costs (4 ) 1 (3 ) Other comprehensive income $ 123 $ (65 ) $ 58 For the year ended December 31, 2016 Unrealized foreign exchange (loss) gain on: Translation of the net investment in U.S. subsidiaries $ (132 ) $ — $ (132 ) Translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries (Note 17) 150 (20 ) 130 Change in derivatives designated as cash flow hedges: Realized loss on cash flow hedges recognized in income 10 (2 ) 8 Unrealized loss on cash flow hedges (12 ) 2 (10 ) Change in pension and other benefits actuarial gains and losses (422 ) 113 (309 ) Change in prior service pension and other benefit costs (12 ) 3 (9 ) Other comprehensive loss $ (418 ) $ 96 $ (322 ) For the year ended December 31, 2015 Unrealized foreign exchange gain (loss) on: Translation of the net investment in U.S. subsidiaries $ 671 $ — $ 671 Translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries (Note 17) (757 ) 100 (657 ) Change in derivatives designated as cash flow hedges: Realized loss on cash flow hedges recognized in income 7 (2 ) 5 Unrealized loss on cash flow hedges (76 ) 21 (55 ) Change in pension and other benefits actuarial gains and losses 1,058 (281 ) 777 Change in prior service pension and other benefit costs 1 — 1 Other comprehensive income $ 904 $ (162 ) $ 742 The components of Accumulated other comprehensive loss, net of tax, are as follows: (in millions of Canadian dollars) 2017 2016 Unrealized foreign exchange gain on translation of the net investment in U.S. subsidiaries $ 443 $ 738 Unrealized foreign exchange loss on translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries (334 ) (611 ) Net deferred and unrealized losses on derivatives (88 ) (102 ) Amounts for defined benefit pension and other post-retirement plans not recognized in income (Note 20) (1,761 ) (1,822 ) Equity accounted investments (1 ) (2 ) Accumulated other comprehensive loss $ (1,741 ) $ (1,799 ) Changes in Accumulated other comprehensive loss by component are as follows: (in millions of Canadian dollars) Foreign currency (1) Derivatives and (1) Pension and post- (1) Total (1) Opening balance, 2017 $ 127 $ (104 ) $ (1,822 ) $ (1,799 ) Other comprehensive loss before reclassifications (17 ) (4 ) (50 ) (71 ) Amounts reclassified from accumulated other comprehensive loss (1 ) 19 111 129 Net current-period other comprehensive (loss) income (18 ) 15 61 58 Closing balance, 2017 $ 109 $ (89 ) $ (1,761 ) $ (1,741 ) Opening balance, 2016 $ 129 $ (102 ) $ (1,504 ) $ (1,477 ) Other comprehensive loss before reclassifications (2 ) (10 ) (456 ) (468 ) Amounts reclassified from accumulated other comprehensive loss — 8 138 146 Net current-period other comprehensive loss (2 ) (2 ) (318 ) (322 ) Closing balance, 2016 $ 127 $ (104 ) $ (1,822 ) $ (1,799 ) (1) Amounts are presented net of tax. Amounts in Pension and post-retirement defined benefit plans reclassified from Accumulated other comprehensive loss are as follows: 2017 2016 Amortization of prior service costs (1) $ (4 ) $ (6 ) Recognition of net actuarial loss (1) 154 194 Total before income tax $ 150 $ 188 Income tax recovery (39 ) (50 ) Net of income tax $ 111 $ 138 (1)

Change in Non-Cash Working Capi

Change in Non-Cash Working Capital Balances Related to Operations	12 Months Ended
	Dec. 31, 2017
Supplemental Cash Flow Elements [Abstract]
Change in Non-Cash Working Capital Balances Related to Operations	Change in non-cash working capital balances related to operations (in millions of Canadian dollars) 2017 2016 2015 (Use) source of cash: Accounts receivable, net $ (91 ) $ 44 $ 80 Materials and supplies 9 14 15 Other current assets (26 ) (18 ) 55 Accounts payable and accrued liabilities (30 ) (95 ) 125 Change in non-cash working capital $ (138 ) $ (55 ) $ 275

Accounts Receivable, Net

Accounts Receivable, Net	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Accounts Receivable, Net	Accounts receivable, net (in millions of Canadian dollars) 2017 2016 Freight $ 536 $ 461 Non-freight 176 162 712 623 Allowance for doubtful accounts (25 ) (32 ) Total accounts receivable, net $ 687 $ 591 The Company maintains an allowance for doubtful accounts based on expected collectability of accounts receivable. Credit losses are based on specific identification of uncollectable accounts, the application of historical percentages by aging category and an assessment of the current economic environment. At December 31, 2017 , allowances of $25 million ( 2016 – $32 million ) were recorded in “Accounts receivable, net”. During 2017 , provisions of $3 million of accounts receivable ( 2016 – $7 million ; 2015 – $7 million

Disposition of properties

Disposition of properties	12 Months Ended
	Dec. 31, 2017
Discontinued Operations and Disposal Groups [Abstract]
Disposition of properties	Dispositions of properties Gain on sale of Obico During the fourth quarter of 2016, the Company completed the sale of its Obico rail yard, for gross proceeds of $38 million . The Company recorded a gain on sale of $37 million ( $33 million after tax) within "Purchased services and other" from the transaction. Gain on sale of Arbutus Corridor In March 2016, the Company completed the sale of CP’s Arbutus Corridor (the “Arbutus Corridor”) to the City of Vancouver for gross proceeds of $55 million . The agreement allows the Company to share in future proceeds on the eventual development and/or sale of certain parcels of the Arbutus Corridor. The Company recorded a gain on sale of $50 million ( $43 million after tax) within "Purchased services and other" from the transaction during the first quarter of 2016. Gain on sale of Delaware & Hudson South During the first quarter of 2015, the Company finalized a sales agreement with Norfolk Southern Corporation ("NS") for approximately 283 miles of the Delaware and Hudson Railway Company, Inc.'s line between Sunbury, Pennsylvania, and Schenectady, New York ("D&H South"). The sale, which received approval by the U.S. Surface Transportation Board (“STB”) on May 15, 2015, was completed on September 18, 2015 for proceeds of $281 million (U.S. $214 million ). The Company recorded a gain on sale of $68 million ( $42 million after tax) from the transaction during the third quarter of 2015. Gain on settlement of legal proceedings related to the purchase and sale of a building In 2013, CP provided an interest-free loan pursuant to a court order to a corporation owned by a court appointed trustee (“the judicial trustee”) to facilitate the acquisition of a building. The building was held in trust during the legal proceedings with regard to CP’s entitlement to an exercised purchase option of the building (“purchase option”). As at December 31, 2014, the loan of $20 million and the purchase option with a carrying value of $8 million , were recorded as “Other assets” in the Company’s Consolidated Balance Sheets. In the first quarter of 2015, CP reached a settlement with a third party that, following the sale of the building to an arm’s-length third party, resulted in resolution of legal proceedings. CP received $59 million for the sale of the building which included repayment of the aforementioned loan to the judicial trustee. A gain of $31 million ( $27 million after tax) was recorded as a credit within “Purchased services and other”.

Investments

Investments	12 Months Ended
	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Investments	Investments (in millions of Canadian dollars) 2017 2016 Rail investments accounted for on an equity basis $ 144 $ 136 Other investments 38 58 Total investments $ 182 $ 194

Properties

Properties	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Properties	Properties (in millions of Canadian dollars except percentages) 2017 2017 2016 Weighted average annual depreciation rate Cost Accumulated Net book Cost Accumulated Net book Track and roadway 2.8 % $ 17,285 $ 4,814 $ 12,471 $ 16,817 $ 4,573 $ 12,244 Buildings 3.0 % 719 196 523 662 178 484 Rolling stock 2.9 % 4,114 1,557 2,557 4,060 1,524 2,536 Information systems (1) 11.4 % 551 264 287 584 299 285 Other 5.1 % 1,760 582 1,178 1,691 551 1,140 Total $ 24,429 $ 7,413 $ 17,016 $ 23,814 $ 7,125 $ 16,689 (1) During 2017 , CP capitalized costs attributable to the design and development of internal-use software in the amount of $49 million ( 2016 – $46 million ; 2015 – $42 million ). Current year depreciation expense related to internal use software was $55 million ( 2016 – $63 million ; 2015 – $69 million ). Capital leases included in properties (in millions of Canadian dollars) 2017 2016 Cost Accumulated Net book Cost Accumulated Net book Buildings $ 1 $ 1 $ — $ 1 $ 1 $ — Rolling stock 311 115 196 311 105 206 Total assets held under capital lease $ 312 $ 116 $ 196 $ 312 $ 106 $ 206

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and intangible assets Goodwill Intangible assets (in millions of Canadian dollars) Net Cost Accumulated Net Total goodwill and intangible assets Balance at December 31, 2015 $ 198 $ 22 $ (9 ) $ 13 $ 211 Amortization — — (1 ) (1 ) (1 ) Foreign exchange impact (7 ) — (1 ) (1 ) (8 ) Balance at December 31, 2016 $ 191 $ 22 $ (11 ) $ 11 $ 202 Amortization — — (1 ) (1 ) (1 ) Foreign exchange impact (13 ) — (1 ) (1 ) (14 ) Balance at December 31, 2017 $ 178 $ 22 $ (13 ) $ 9 $ 187

Other Assets

Other Assets	12 Months Ended
	Dec. 31, 2017
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets	Other assets (in millions of Canadian dollars) 2017 2016 Long-term materials $ 24 $ 22 Prepaid leases 5 6 Unamortized fees on credit facility 5 7 Contracted customer incentives 11 2 Long-term receivables 1 2 Other 23 18 Total other assets $ 69 $ 57

Accounts Payable and Accrued Li

Accounts Payable and Accrued Liabilities	12 Months Ended
	Dec. 31, 2017
Payables and Accruals [Abstract]
Accounts Payable and Accrued Liabilities	Accounts payable and accrued liabilities (in millions of Canadian dollars) 2017 2016 Trade payables $ 402 $ 352 Accrued charges 256 282 Income and other taxes payable 72 146 Accrued interest 128 137 Financial derivative liability (Note 17) 55 69 Payroll-related accruals 72 73 Accrued vacation 59 65 Dividends payable 82 73 Personal injury and other claims provision 28 26 Provision for environmental remediation (Note 18) 8 9 Stock-based compensation liabilities 32 40 Other 44 50 Total accounts payable and accrued liabilities $ 1,238 $ 1,322

Debt

Debt	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Debt	Debt (in millions of Canadian dollars except percentages) Maturity Currency 2017 2016 6.500% 10-year Notes (A) May 2018 U.S.$ $ 345 $ 369 6.250% 10-year Medium Term Notes (A) Jun 2018 CDN$ 375 375 7.250% 10-year Notes (A) May 2019 U.S.$ 439 469 9.450% 30-year Debentures (A) Aug 2021 U.S.$ 314 336 5.100% 10-year Medium Term Notes (A) Jan 2022 CDN$ 125 125 4.500% 10-year Notes (A) Jan 2022 U.S.$ 311 333 4.450% 12.5-year Notes (A) Mar 2023 U.S.$ 438 469 2.900% 10-year Notes (A) Feb 2025 U.S.$ 878 940 3.700% 10.5-year Notes (A) Feb 2026 U.S.$ 313 335 7.125% 30-year Debentures (A) Oct 2031 U.S.$ 439 470 5.750% 30-year Debentures (A) Mar 2033 U.S.$ 307 328 4.800% 20-year Notes (A) Sep 2035 U.S.$ 375 401 5.950% 30-year Notes (A) May 2037 U.S.$ 558 597 6.450% 30-year Notes (A) Nov 2039 CDN$ 400 400 5.750% 30-year Notes (A) Jan 2042 U.S.$ 308 330 4.800% 30-year Notes (A) Aug 2045 U.S.$ 687 736 6.125% 100-year Notes (A) Sep 2115 U.S.$ 1,129 1,208 5.41% Senior Secured Notes (B) Mar 2024 U.S.$ 111 126 6.91% Secured Equipment Notes (C) Oct 2024 CDN$ 120 133 7.49% Equipment Trust Certificates (D) Jan 2021 U.S.$ 52 56 Obligations under capital leases 6.57% – 6.99% (E) 2022 – 2026 U.S.$ 148 163 12.77% (E) Jan 2031 CDN$ 3 3 8,175 8,702 Perpetual 4% Consolidated Debenture Stock (F) U.S.$ 38 41 Perpetual 4% Consolidated Debenture Stock (F) G.B.£ 6 6 8,219 8,749 Less: Unamortized fees on long-term debt 60 65 8,159 8,684 Less: Long-term debt maturing within one year 746 25 $ 7,413 $ 8,659 At December 31, 2017 , the gross amount of long-term debt denominated in U.S. dollars was U.S. $5,755 million ( 2016 – U.S. $5,763 million). Annual maturities and principal repayment requirements, excluding those pertaining to capital leases, for each of the five years following 2017 are (in millions): 2018 – $742 ; 2019 – $462 ; 2020 – $63 ; 2021 – $353 ; 2022 – $466 . Fees on long-term debt are amortized to income over the term of the related debt. A. These debentures and notes pay interest semi-annually and are unsecured, but carry a negative pledge. B. The 5.41% Senior Secured Notes are collateralized by specific locomotive units with a carrying value of $118 million at December 31, 2017 . The Company pays equal blended semi-annual payments of principal and interest. Final repayment of the remaining principal of U.S. $44 million is due in March 2024. C. The 6.91% Secured Equipment Notes are full recourse obligations of the Company collateralized by a first charge on specific locomotive units with a carrying value of $107 million at December 31, 2017 . The Company pays equal blended semi-annual payments of principal and interest. Final repayment of the remaining principal of $11 million is due in October 2024. D. The 7.49% Equipment Trust Certificates are secured by specific locomotive units with a carrying value of $104 million at December 31, 2017 . The Company makes semi-annual payments that vary in amount and are interest-only payments or blended principal and interest payments. Final repayment of the remaining principal of U.S. $11 million is due in January 2021. E. At December 31, 2017 , capital lease obligations included in long-term debt were as follows: (in millions of Canadian dollars) Year Capital leases Minimum lease payments in: 2018 $ 15 2019 15 2020 15 2021 15 2022 105 Thereafter 37 Total minimum lease payments 202 Less: Imputed interest (51 ) Present value of minimum lease payments 151 Less: Current portion (4 ) Long-term portion of capital lease obligations $ 147 During the years ended 2017 , 2016 , and 2015 , the Company had no additions to property, plant and equipment under capital lease obligations. The carrying value of the assets collateralizing the capital lease obligations was $196 million at December 31, 2017 . F. The Consolidated Debenture Stock, authorized by an Act of Parliament of 1889, constitutes a first charge upon and over the whole of the undertaking, railways, works, rolling stock, plant, property and effects of the Company, with certain exceptions. Credit facility CP has a revolving credit facility (the “facility”) agreement with 16 highly rated financial institutions for a commitment amount of U.S. $2.0 billion . The facility includes a U.S. $1.0 billion one-year plus one-year term-out portion and a U.S. $1.0 billion five-year portion. The facility can accommodate draws of cash and/or letters of credit at market competitive pricing. The agreement requires the Company not to exceed a maximum debt to earnings before interest, tax, depreciation, and amortization ratio. As at December 31, 2017 and 2016 , the Company was in compliance with all terms and conditions of the credit facility arrangements and satisfied the threshold stipulated in this financial covenant. Effective June 23, 2017, the Company extended the maturity date by one year on its existing revolving U.S. $2.0 billion credit facility, which includes a U.S. $1.0 billion five-year portion and U.S. $1.0 billion one-year plus one-year term-out portion. The maturity date on the first U.S. $1.0 billion tranche was extended to June 27, 2019 ; the maturity date on the second U.S. $1.0 billion tranche was extended to June 28, 2022 . As at December 31, 2017 and 2016 , the facility was undrawn. The amount available under the terms of the credit facility was U.S. $2.0 billion at December 31, 2017 (December 31, 2016 – U.S. $2.0 billion ). The Company also has a commercial paper program which enables it to issue commercial paper up to a maximum aggregate principal amount of U.S. $1.0 billion in the form of unsecured promissory notes. The commercial paper program is backed by the U.S. $1.0 billion one-year plus one-year term-out portion of the revolving credit facility. As at December 31, 2017 , the Company had no commercial paper borrowings outstanding (December 31, 2016 – $ nil ). CP has bilateral letter of credit facilities with six highly rated financial institutions to support its requirement to post letters of credit in the ordinary course of business. Under these agreements, the Company has the option to post collateral in the form of cash or cash equivalents, equal at least to the face value of the letter of credit issued. These agreements permit CP to withdraw amounts posted as collateral at any time; therefore, the amounts posted as collateral are presented as “Cash and cash equivalents” on the Company’s Consolidated Balance Sheets. As at December 31, 2017, the Company had $150 million posted as collateral on its bilateral letters of credit facility (December 31, 2016 – $ nil ). At December 31, 2017 , under its bilateral facilities the Company had letters of credit drawn of $319 million ( December 31, 2016 – $320 million ) from a total available amount of $600 million ( December 31, 2016 – $600 million

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Financial Instruments	Financial instruments A. Fair values of financial instruments The Company categorizes its financial assets and liabilities measured at fair value into a three-level hierarchy established by GAAP that prioritizes those inputs to valuation techniques used to measure fair value based on the degree to which they are observable. The three levels of the fair value hierarchy are as follows: Level 1 inputs are quoted prices in active markets for identical assets and liabilities; Level 2 inputs, other than quoted prices included within Level 1, are observable for the asset or liability either directly or indirectly; and Level 3 inputs are not observable in the market. When possible, the estimated fair value is based on quoted market prices and, if not available, it is based on estimates from third-party brokers. For non-exchange traded derivatives classified in Level 2, the Company uses standard valuation techniques to calculate fair value. Primary inputs to these techniques include observable market prices (interest, FX and commodity) and volatility, depending on the type of derivative and nature of the underlying risk. The Company uses inputs and data used by willing market participants when valuing derivatives and considers its own credit default swap spread as well as those of its counterparties in its determination of fair value. All derivatives and long-term debt are classified as Level 2. The carrying values of financial instruments equal or approximate their fair values with the exception of long-term debt: (in millions of Canadian dollars) December 31, 2017 December 31, 2016 Long-term debt (including current maturities): Fair value $ 9,680 $ 9,981 Carrying value 8,159 8,684 The estimated fair value of current and long-term borrowings has been determined based on market information where available, or by discounting future payments of principal and interest at estimated interest rates expected to be available to the Company at period end. As at December 31, 2017 and 2016 , the Company did not have any deposits in the form of short-term investments with financial institutions. B. Financial risk management Derivative financial instruments Derivative financial instruments may be used to selectively reduce volatility associated with fluctuations in interest rates, FX rates, the price of fuel and stock-based compensation expense. Where derivatives are designated as hedging instruments, the relationship between the hedging instruments and their associated hedged items is documented, as well as the risk management objective and strategy for the use of the hedging instruments. This documentation includes linking the derivatives that are designated as fair value or cash flow hedges to specific assets or liabilities on the Consolidated Balance Sheets, commitments or forecasted transactions. At the time a derivative contract is entered into and at least quarterly thereafter, an assessment is made as to whether the derivative item is effective in offsetting the changes in fair value or cash flows of the hedged items. The derivative qualifies for hedge accounting treatment if it is effective in substantially mitigating the risk it was designed to address. It is not the Company’s intent to use financial derivatives or commodity instruments for trading or speculative purposes. Credit risk management Credit risk refers to the possibility that a customer or counterparty will fail to fulfill its obligations under a contract and as a result create a financial loss for the Company. The railway industry predominantly serves financially established customers, and the Company has experienced limited financial losses with respect to credit risk. The credit worthiness of customers is assessed using credit scores supplied by a third party, and through direct monitoring of their financial well-being on a continual basis. The Company establishes guidelines for customer credit limits and should thresholds in these areas be reached, appropriate precautions are taken to improve collectability. Counterparties to financial instruments expose the Company to credit losses in the event of non-performance. Counterparties for derivative and cash transactions are limited to high credit quality financial institutions, which are monitored on an ongoing basis. Counterparty credit assessments are based on the financial health of the institutions and their credit ratings from external agencies. The Company does not anticipate non-performance that would materially impact the Company’s financial statements. In addition, the Company believes there are no significant concentrations of credit risk. FX management The Company conducts business transactions and owns assets in both Canada and the United States. As a result, the Company is exposed to fluctuations in the value of financial commitments, assets, liabilities, income or cash flows due to changes in FX rates. The Company may enter into FX risk management transactions primarily to manage fluctuations in the exchange rate between Canadian and U.S. currencies. FX exposure is primarily mitigated through natural offsets created by revenues, expenditures and balance sheet positions incurred in the same currency. Where appropriate, the Company may negotiate with customers and suppliers to reduce the net exposure. Occasionally the Company may enter into short-term FX forward contracts as part of its cash management strategy. Net investment hedge The FX gains and losses on long-term debt are mainly unrealized and can only be realized when U.S. dollar-denominated long-term debt matures or is settled. The Company also has long-term FX exposure on its investment in U.S. affiliates. The majority of the Company’s U.S. dollar-denominated long-term debt has been designated as a hedge of the net investment in foreign subsidiaries. This designation has the effect of mitigating volatility on Net income by offsetting long-term FX gains and losses on U.S. dollar-denominated long-term debt and gains and losses on its net investment. The effective portion recognized in “Other comprehensive income” in 2017 was an FX gain of $319 million , the majority of which was unrealized ( 2016 – unrealized gain of $150 million ; 2015 – unrealized loss of $757 million ) (see Note 7). There was no ineffectiveness during 2017 ( 2016 – $ nil ; 2015 – $ nil ). FX forward contracts The Company may enter into FX forward contracts to lock-in the amount of Canadian dollars it has to pay on U.S. dollar-denominated debt maturities. At December 31, 2017 , the Company had a negligible amount of net unamortized gains related to FX forward contracts to fix the exchange rate on U.S. dollar-denominated debt maturities settled in previous years ( December 31, 2016 – $1 million ). During 2017 , $1 million of pretax gain related to these previously settled derivatives has been amortized from "Accumulated other comprehensive loss" to “Other income and charges” ( December 31, 2016 – $1 million ). The Company expects that during the next 12 months, a negligible amount of pretax gain will be reclassified to “Other income and charges”. At December 31, 2017 and 2016 , the Company had no remaining FX forward contracts to fix the exchange rate on U.S. dollar-denominated debt maturities. Interest rate management The Company is exposed to interest rate risk, which is the risk that the fair value or future cash flows of a financial instrument will vary as a result of changes in market interest rates. In order to manage funding needs or capital structure goals, the Company enters into debt or capital lease agreements that are subject to either fixed market interest rates set at the time of issue or floating rates determined by ongoing market conditions. Debt subject to variable interest rates exposes the Company to variability in interest expense, while debt subject to fixed interest rates exposes the Company to variability in the fair value of debt. To manage interest rate exposure, the Company accesses diverse sources of financing and manages borrowings in line with a targeted range of capital structure, debt ratings, liquidity needs, maturity schedule, and currency and interest rate profiles. In anticipation of future debt issuances, the Company may enter into forward rate agreements, that are designated as cash flow hedges, to substantially lock in all or a portion of the effective future interest expense. The Company may also enter into swap agreements, designated as fair value hedges, to manage the mix of fixed and floating rate debt. Forward starting swaps As at December 31, 2017 , the Company had forward starting floating-to-fixed interest rate swap agreements (“forward starting swaps”) totalling a notional amount of U.S. $500 million to fix the benchmark rate on cash flows associated with highly probable forecasted issuances of long-term notes (December 31, 2016 – U.S. $700 million ). The effective portion of changes in fair value on the forward starting swaps is recorded in “Accumulated other comprehensive loss”, net of tax, as cash flow hedges until the highly probable forecasted notes are issued. Subsequent to the notes issuance, amounts in “Accumulated other comprehensive loss” are reclassified to “Net interest expense”. During the second quarter of 2016, the Company de-designated a notional amount of U.S. $700 million of forward starting swaps. The Company did not cash settle these swaps, and there was no ineffectiveness to record upon de-designation. Concurrently, the Company re-designated and rolled the forward starting swaps totalling U.S. $700 million to fix the benchmark rate on cash flows associated with a highly probable forecasted debt issuance of long-term notes. During the second quarter of 2017, the Company de-designated the hedging relationship for U.S. $700 million of forward starting swaps. The Company settled a notional amount of U.S. $200 million of forward starting swaps for a cash payment of U.S. $16 million ( $22 million ). The Company rolled the remaining notional amount of U.S. $500 million of forward starting swaps and did not cash settle these swaps. The impact of the U.S. $200 million settlement and U.S. $500 million roll of the forward starting swaps was a charge of $13 million to "Other income and charges" on the Company's Consolidated Statements of Income. Concurrently, the Company re-designated the forward starting swaps totalling U.S. $500 million to fix the benchmark rate on cash flows associated with highly probable forecasted issuances of long-term notes. As at December 31, 2017 , the total fair value loss of $55 million ( December 31, 2016 – fair value loss of $69 million ) derived from the forward starting swaps was included in “Accounts payable and accrued liabilities”. Changes in fair value from the forward starting swaps for the year ended December 31, 2017 was a loss of $8 million ( 2016 – a loss of $9 million ). The effective portion for the year ended December 31, 2017 was a loss of $7 million ( 2016 – loss of $12 million ) and was recorded in “Other comprehensive income”. In addition to the charge on hedge roll and de-designation, for the year ended December 31, 2017 , an ineffectiveness loss of $1 million ( 2016 – gain of $3 million ) was recorded in “Net interest expense” on the Consolidated Statements of Income. For the year ended December 31, 2017 , a loss of $11 million related to previous forward starting swap hedges has been amortized to “Net interest expense” ( 2016 – a loss of $11 million ). The Company expects that during the next 12 months, $12 million of losses will be amortized to “Net interest expense”. Treasury rate locks At December 31, 2017 , the Company had net unamortized losses related to interest rate locks, which are accounted for as cash flow hedges, settled in previous years totalling $20 million ( December 31, 2016 – $21 million ). This amount is composed of various unamortized gains and losses related to specific debts which are reflected in “Accumulated other comprehensive loss” and are amortized to “Net interest expense” in the period that interest on the related debt is charged. The amortization of these gains and losses resulted in a $1 million increase to “Net interest expense” and “Other comprehensive income” in 2017 ( 2016 – negligible; 2015 – negligible). The Company expects that during the next 12 months, a net loss of $1 million related to these previously settled derivatives will be reclassified to “Net interest expense”. Fuel price management The Company is exposed to commodity risk related to purchases of diesel fuel and the potential reduction in Net income due to increases in the price of diesel. Fuel expense constitutes a large portion of the Company’s operating costs and volatility in diesel fuel prices can have a significant impact on the Company’s income. Items affecting volatility in diesel prices include, but are not limited to, fluctuations in world markets for crude oil and distillate fuels, which can be affected by supply disruptions and geopolitical events.

Other Long-Term Liabilities

Other Long-Term Liabilities	12 Months Ended
	Dec. 31, 2017
Other Liabilities Disclosure [Abstract]
Other Long-Term Liabilities	Other long-term liabilities (in millions of Canadian dollars) 2017 2016 Provision for environmental remediation, net of current portion (1) $ 70 $ 76 Stock-based compensation liabilities, net of current portion 67 72 Deferred revenue on rights-of-way license agreements, net of current portion (2) 26 29 Deferred retirement compensation 4 29 Deferred gains on sale leaseback transactions (2) 16 19 Other, net of current portion 48 59 Total other long-term liabilities $ 231 $ 284 (1) As at December 31, 2017 , the aggregate provision for environmental remediation, including the current portion was $78 million ( 2016 – $85 million ). (2) The deferred revenue on rights-of-way license agreements, and deferred gains on sale leaseback transactions are being amortized to income on a straight-line basis over the related lease terms. Environmental remediation accruals Environmental remediation accruals cover site-specific remediation programs. The estimate of the probable costs to be incurred in the remediation of properties contaminated by past railway use reflects the nature of contamination at individual sites according to typical activities and scale of operations conducted. CP has developed remediation strategies for each property based on the nature and extent of the contamination, as well as the location of the property and surrounding areas that may be adversely affected by the presence of contaminants, considering available technologies, treatment and disposal facilities and the acceptability of site-specific plans based on the local regulatory environment. Site-specific plans range from containment and risk management of the contaminants through to the removal and treatment of the contaminants and affected soils and groundwater. The details of the estimates reflect the environmental liability at each property. Provisions for environmental remediation costs are recorded in “Other long-term liabilities”, except for the current portion which is recorded in “Accounts payable and accrued liabilities” (see Note 15). Payments are expected to be made over 10 years to 2027. The accruals for environmental remediation represent CP’s best estimate of its probable future obligation and include both asserted and unasserted claims, without reduction for anticipated recoveries from third parties. Although the recorded accruals include CP’s best estimate of all probable costs, CP’s total environmental remediation costs cannot be predicted with certainty. Accruals for environmental remediation may change from time to time as new information about previously untested sites becomes known, environmental laws and regulations evolve and advances are made in environmental remediation technology. The accruals may also vary as the courts decide legal proceedings against outside parties responsible for contamination. These potential charges, which cannot be quantified at this time, may materially affect income in the particular period in which a charge is recognized. Costs related to existing, but as yet unknown, or future contamination will be accrued in the period in which they become probable and reasonably estimable. Changes to costs are reflected as changes to “Other long-term liabilities” or “Accounts payable and accrued liabilities” on the Company's Consolidated Balance Sheets and to “Purchased services and other” within operating expenses on the Company's Consolidated Statements of Income. The amount charged to income in 2017 was $5 million ( 2016 – $6 million ; 2015 – $7 million

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Shareholders' Equity	Shareholders’ equity Authorized and issued share capital The Company is authorized to issue an unlimited number of Common Shares, an unlimited number of First Preferred Shares and an unlimited number of Second Preferred Shares. At December 31, 2017 , no First or Second Preferred Shares had been issued. The following table summarizes information related to Common Share balances as at December 31: (number of shares in millions) 2017 2016 2015 Share capital, January 1 146.3 153.0 166.1 CP Common Shares repurchased (1.9 ) (6.9 ) (13.7 ) Shares issued under stock option plan 0.5 0.2 0.6 Share capital, December 31 144.9 146.3 153.0 The change in the “Share capital” balances includes $ nil related to the cancellation of the tandem share appreciation rights liability on exercise of tandem stock options ( 2016 – $1 million ; 2015 – $2 million ), and $12 million of stock-based compensation transferred from “Additional paid-in capital” ( 2016 – $5 million ; 2015 – $10 million ). Share repurchase On March 11, 2014, the Company announced a new share repurchase program to implement a normal course issuer bid (“NCIB”) to purchase, for cancellation, up to 5.3 million Common Shares before March 16, 2015 . On September 29, 2014, the Company announced the amendment of the bid to increase the maximum number of its Common Shares that may be purchased from 5.3 million to 12.7 million of its outstanding Common Shares. The Company completed the purchase of 10.5 million Common Shares in 2014. An additional 2.2 million Common Shares were purchased for $490 million in the first quarter of 2015 prior to the March 16, 2015 expiry date of the program. On March 16, 2015, the Company announced the renewal of its NCIB, commencing March 18, 2015, to purchase up to 9.1 million of its outstanding Common Shares for cancellation before March 17, 2016 . On August 31, 2015, the Company amended the NCIB to increase the maximum number of its Common Shares that may be purchased from 9.1 million to 11.9 million of its outstanding Common Shares. As at December 31, 2015, the Company had purchased 11.3 million Common Shares for $2,258 million under this NCIB program. On April 20, 2016, the Company announced a new NCIB, commencing May 2, 2016 to May 1, 2017 , to purchase up to 6.9 million of its outstanding Common Shares for cancellation. The Company completed this NCIB on September 28, 2016. On May 10, 2017, the Company announced a new NCIB, commencing May 15, 2017, to purchase up to 4.38 million Common Shares for cancellation before May 14, 2018 . As at December 31, 2017, the Company had purchased 1.9 million Common Shares for $381 million under this NCIB program. All purchases are made in accordance with the respective NCIB at prevalent market prices plus brokerage fees, or such other prices that may be permitted by the Toronto Stock Exchange, with consideration allocated to share capital up to the average carrying amount of the shares, and any excess allocated to "Retained earnings". The following table provides the activities under the share repurchase programs: 2017 2016 2015 Number of Common Shares repurchased 1,888,100 6,910,000 13,549,977 Weighted-average price per share (1) $ 201.53 $ 175.08 $ 202.79 Amount of repurchase (in millions) (1) $ 381 $ 1,210 $ 2,748 (1)

Pensions and Other Benefits

Pensions and Other Benefits	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Pensions and Other Benefits	Pensions and other benefits The Company has both defined benefit (“DB”) and defined contribution (“DC”) pension plans. At December 31, 2017 , the Canadian pension plans represent approximately 99% of total combined pension plan assets and approximately 98% of total combined pension plan obligations. The DB plans provide for pensions based principally on years of service and compensation rates near retirement. Pensions for Canadian pensioners are partially indexed to inflation. Annual employer contributions to the DB plans, which are actuarially determined, are made on the basis of being not less than the minimum amounts required by federal pension supervisory authorities. The Company has other benefit plans including post-retirement health and life insurance for pensioners, and post-employment long-term disability and workers’ compensation benefits, which are based on Company-specific claims. At December 31, 2017 , the Canadian other benefits plans represent approximately 96% of total combined other plan obligations. The Finance Committee of the Board of Directors has approved an investment policy that establishes long-term asset mix targets which take into account the Company’s expected risk tolerances. Pension plan assets are managed by a suite of independent investment managers, with the allocation by manager reflecting these asset mix targets. Most of the assets are actively managed with the objective of outperforming applicable benchmarks. In accordance with the investment policy, derivative instruments may be used to hedge or adjust existing or anticipated exposures. To develop the expected long-term rate of return assumption used in the calculation of net periodic benefit cost applicable to the market-related value of assets, the Company considers the expected composition of the plans’ assets, past experience and future estimates of long-term investment returns. Future estimates of investment returns reflect the expected annual yield on applicable fixed income capital market indices, and the long-term return expectation for public equity, real estate, infrastructure and absolute return investments and the expected added value (relative to applicable benchmark indices) from active management of pension fund assets. The Company has elected to use a market-related value of assets for the purpose of calculating net periodic benefit cost, developed from a five years average of market values for the plans’ public equity and absolute return investments (with each prior year’s market value adjusted to the current date for assumed investment income during the intervening period) plus the market value of the plans’ fixed income, real estate and infrastructure securities. The benefit obligation is discounted using a discount rate that is a blended yield to maturity for a hypothetical portfolio of high-quality corporate debt instruments with cash flows matching projected benefit payments. The discount rate is determined by management. Net periodic benefit cost The elements of net periodic benefit cost for DB pension plans and other benefits recognized in the year include the following components: Pensions Other benefits (in millions of Canadian dollars) 2017 2016 2015 2017 2016 2015 Current service cost (benefits earned by employees in the year) $ 103 $ 106 $ 126 $ 12 $ 11 $ 12 Other components of net periodic benefit (recovery) cost: Interest cost on benefit obligation 451 467 463 20 21 21 Expected return on fund assets (893 ) (846 ) (816 ) — — — Recognized net actuarial loss (gain) 153 190 265 (1 ) 7 2 Amortization of prior service costs (5 ) (7 ) (6 ) 1 1 1 Total other components of net periodic benefit (recovery) cost (294 ) (196 ) (94 ) 20 29 24 Net periodic benefit (recovery) cost $ (191 ) $ (90 ) $ 32 $ 32 $ 40 $ 36 Projected benefit obligation, fund assets, and funded status Information about the Company’s DB pension plans and other benefits, in aggregate, is as follows: Pensions Other benefits (in millions of Canadian dollars) 2017 2016 2017 2016 Change in projected benefit obligation: Benefit obligation at January 1 $ 11,399 $ 11,194 $ 510 $ 513 Current service cost 103 106 12 11 Interest cost 451 467 20 21 Employee contributions 44 40 1 1 Benefits paid (648 ) (645 ) (35 ) (31 ) Foreign currency changes (15 ) (7 ) (3 ) — Plan amendments and other 1 6 — — Actuarial loss (gain) 344 238 13 (5 ) Projected benefit obligation at December 31 $ 11,679 $ 11,399 $ 518 $ 510 Pensions Other benefits (in millions of Canadian dollars) 2017 2016 2017 2016 Change in fund assets: Fair value of fund assets at January 1 $ 12,196 $ 12,300 $ 5 $ 6 Actual return on fund assets 1,183 461 (1 ) (1 ) Employer contributions 46 48 34 30 Employee contributions 44 40 1 1 Benefits paid (648 ) (645 ) (35 ) (31 ) Foreign currency changes (13 ) (8 ) — — Fair value of fund assets at December 31 $ 12,808 $ 12,196 $ 4 $ 5 Funded status – plan surplus (deficit) $ 1,129 $ 797 $ (514 ) $ (505 ) 2017 2016 (in millions of Canadian dollars) Pension Pension Pension Pension Projected benefit obligation at December 31 $ (11,174 ) $ (505 ) $ (10,902 ) $ (497 ) Fair value of fund assets at December 31 12,581 227 11,972 224 Funded Status $ 1,407 $ (278 ) $ 1,070 $ (273 ) All Other benefits plans were in a deficit position at December 31, 2017 and 2016 . Pension asset and liabilities in the Company’s Consolidated Balance Sheets Amounts recognized in the Company’s Consolidated Balance Sheets are as follows: Pensions Other benefits (in millions of Canadian dollars) 2017 2016 2017 2016 Pension asset $ 1,407 $ 1,070 $ — $ — Accounts payable and accrued liabilities (10 ) (10 ) (33 ) (34 ) Pension and other benefit liabilities (268 ) (263 ) (481 ) (471 ) Total amount recognized $ 1,129 $ 797 $ (514 ) $ (505 ) The defined benefit pension plans’ accumulated benefit obligation as at December 31, 2017 was $11,273 million ( 2016 – $11,143 million ). The accumulated benefit obligation is calculated on a basis similar to the projected benefit obligation, except no future salary increases are assumed in the projection of future benefits. The measurement date used to determine the plan assets and the accrued benefit obligation is December 31 . The most recent actuarial valuation for pension funding purposes for the Company’s main Canadian pension plan was performed as at January 1, 2017. During 2018 , the Company expects to file a new valuation with the pension regulator. Accumulated other comprehensive loss Amounts recognized in accumulated other comprehensive loss are as follows: Pensions Other benefits (in millions of Canadian dollars) 2017 2016 2017 2016 Net actuarial loss: Other than deferred investment gains $ 2,555 $ 2,842 $ 81 $ 66 Deferred investment gains (178 ) (366 ) — — Prior service cost (2 ) (7 ) 2 3 Deferred income tax (676 ) (699 ) (21 ) (17 ) Total (Note 7) $ 1,699 $ 1,770 $ 62 $ 52 The unamortized actuarial loss and the unamortized prior service cost included in “Accumulated other comprehensive loss” that are expected to be recognized in net periodic benefit cost during 2018 are $114 million and a recovery of $3 million , respectively, for pensions and $3 million and $ nil , respectively, for other post-retirement benefits. Actuarial assumptions Weighted-average actuarial assumptions used were approximately: (percentages) 2017 2016 2015 Benefit obligation at December 31: Discount rate 3.80 4.02 4.22 Projected future salary increases 2.75 2.75 3.00 Health care cost trend rate 7.00 (1) 7.00 (1) 7.00 (2) Benefit cost for year ended December 31: Discount rate 4.02 4.22 4.09 Expected rate of return on fund assets 7.75 7.75 7.75 Projected future salary increases 2.75 3.00 3.00 Health care cost trend rate 7.00 (1) 7.00 (2) 7.00 (2) (1) The health care cost trend rate is assumed to be 7.00% in 2017 and 2018, and then decreasing by 0.50% per year to an ultimate rate of 5.00% per year in 2022 and thereafter. (2) The health care cost trend rate was previously assumed to be 6.50% in 2017 ( 7.00% in 2016 and 2015 ), and then decreasing by 0.50% per year to an ultimate rate of 5.00% per year in 2020 and thereafter. Assumed health care cost trend rates affect the amounts reported for the health care plans. A one-percentage-point increase in the assumed health care cost trend rate would increase the post-retirement benefit obligation by $6 million , and a one-percentage-point decrease in the assumed health care cost trend rate would decrease the post-retirement benefit obligation by $6 million . A one-percentage-point increase or decrease in the assumed health care cost trend rate would have no material effect on the total of service and interest costs. Plan assets Plan assets are recorded at fair value. The major asset categories are public equity securities, fixed income securities, real estate, infrastructure and absolute return investments. The fair values of the public equity and fixed income securities are primarily based on quoted market prices. Real estate values are based on annual valuations performed by external parties, taking into account current market conditions and recent sales transactions where practical and appropriate. Infrastructure values are based on the fair value of each fund’s assets as calculated by the fund manager, generally using a discounted cash flow analysis that takes into account current market conditions and recent sales transactions where practical and appropriate. Absolute return investments are a portfolio of units of externally managed hedge funds and are valued by the fund administrators. The Company’s pension plan asset allocation, the current weighted average asset allocation targets and the current weighted average policy range for each major asset class, were as follows: Current Current Percentage of plan assets Asset allocation (percentage) 2017 2016 Cash and cash equivalents 0.5 0 – 5 1.4 1.1 Fixed income 29.5 20 – 40 26.1 21.4 Public equity 46.0 35 – 55 53.3 53.8 Real estate and infrastructure 12.0 4 – 20 6.2 7.5 Absolute return 12.0 0 – 18 13.0 16.2 Total 100.0 100.0 100.0 Summary of the assets of the Company’s DB pension plans at fair values The following is a summary of the assets of the Company’s DB pension plans at fair values at December 31, 2017 and 2016 : (in millions of Canadian dollars) Quoted prices in Significant other Significant Investments measured at NAV (1) Total December 31, 2017 Cash and cash equivalents $ 165 $ 11 $ — $ — $ 176 Fixed income • Government bonds (2) — 2,087 — — 2,087 • Corporate bonds (2) — 1,215 — — 1,215 • Mortgages (3) — 45 — — 45 Public equities • Canada 1,467 62 — — 1,529 • U.S. and international 5,254 42 — — 5,296 Real estate (4) — — — 622 622 Derivative assets (5) — — — — — Absolute return (6) • Funds of hedge funds — — — 681 681 • Multi-strategy funds — — — 515 515 • Credit funds — — — 252 252 • Equity funds — — — 214 214 Infrastructure (7) — — — 176 176 $ 6,886 $ 3,462 $ — $ 2,460 $ 12,808 December 31, 2016 Cash and cash equivalents $ 121 $ 11 $ — $ — $ 132 Fixed income • Government bonds (2) — 1,357 — — 1,357 • Corporate bonds (2) — 1,186 — — 1,186 • Mortgages (3) — 71 — — 71 Public equities • Canada 1,480 57 — — 1,537 • U.S. and international 4,985 36 — — 5,021 Real estate (4) — — 437 188 625 Derivative assets (5) — 7 — — 7 Absolute return (6) • Funds of hedge funds — — — 668 668 • Multi-strategy funds — — — 502 502 • Credit funds — — — 505 505 • Equity funds — — — 300 300 Infrastructure (7) — — — 285 285 $ 6,586 $ 2,725 $ 437 $ 2,448 $ 12,196 (1) Investments measured at net asset value ("NAV"): Amounts are comprised of certain investments measured at fair value using NAV (or its equivalent) as a practical expedient. These investments have not been classified in the fair value hierarchy. (2) Government & Corporate Bonds: Fair values for bonds are based on market prices supplied by independent sources as of the last trading day. (3) Mortgages: The fair value of mortgages of $45 million ( 2016 – $71 million ) is based on current market yields of financial instruments of similar maturity, coupon and risk factors. (4) Real estate: Real estate fund values of $622 million (2016 – $188 million ) are based on the NAV of the funds that invest directly in real estate investments. The fair values of the investments have been estimated using the capital accounts representing the plan’s ownership interest in the funds. Of the total, $542 million (2016 – $134 million ) is subject to redemption frequencies ranging from monthly to annually and a redemption notice period of 90 days. The remaining $80 million (2016 – $54 million ) is not subject to redemption and is normally returned through distributions as a result of the liquidation of the underlying real estate investments. There are $53 million of unfunded commitments for real estate investments as at December 31, 2017 ( 2016 – $81 million ). The fair value of real estate investments of $ nil ( 2016 – $437 million ) is based on property appraisals which use a number of approaches that typically include a discounted cash flow analysis, a direct capitalization income method and/or a direct comparison approach. Appraisals of real estate investments are generally performed semi-annually by qualified external accredited appraisers. (5) Derivatives: The Company’s pension funds may utilize the following derivative instruments: equity futures to replicate equity index returns (Level 2); currency forwards to partially hedge foreign currency exposures (Level 2); bond forwards to reduce asset/liability interest rate risk exposures (Level 2); interest rate swaps to manage duration and interest rate risk (Level 2); credit default swaps to manage credit risk (Level 2); and options to manage interest rate risk and volatility (Level 2). There are currency forwards with a notional value of $ nil (2016 – $937 million ) and a fair value of $ nil (2016 – $7 million ) as at December 31, 2017. (6) Absolute return: The fair value of absolute return fund investments of $1,662 million ( 2016 – $1,975 million ) is based on the NAV reported by the fund administrators. The funds have different redemption policies and periods. - Funds of hedge funds invest in a portfolio of hedge funds that allocate capital across a broad array of funds and/or investment managers, with monthly redemptions upon 95 days' notice. - Multi-strategy funds include funds that invest in broadly diversified portfolios of equity, fixed income and derivative instruments with quarterly redemptions upon 60 days' notice. - Credit funds invest in an array of fixed income securities with quarterly redemptions upon 60 days' notice. - Equity funds invest primarily in U.S. and global equity securities. Redemptions range from quarterly upon 60 days' notice to triennially upon 45 days' notice. (7) Infrastructure: Infrastructure fund values of $176 million ( 2016 – $285 million ) are based on the NAV of the funds that invest directly in infrastructure investments. The fair values of the investments have been estimated using the capital accounts representing the plans' ownership interest in the funds. The investment in each fund is not subject to redemption and is normally returned through distributions as a result of the liquidation of the underlying infrastructure investments. It was estimated that the investments in these funds will be liquidated over the weighted-average period of approximately one year. Portion of the assets of the Company’s DB pension plans measured at fair value using unobservable inputs (Level 3) During 2016 and 2017 the portion of the assets of the Company’s DB pension plans measured at fair value using unobservable inputs (Level 3) changed as follows: (in millions of Canadian dollars) Real Estate As at January 1, 2016 $ 451 Disbursements (36 ) Net realized gains 24 Decrease in net unrealized gains (2 ) As at December 31, 2016 $ 437 Disbursements (43 ) Net realized gains 7 Decrease in net unrealized gains (7 ) Net transfers (out of) Level 3 (394 ) As at December 31, 2017 $ — Additional plan assets information The Company’s expected long-term target return is 7.75% , net of all fees and expenses. In identifying the asset allocation ranges, consideration was given to the long-term nature of the underlying plan liabilities, the solvency and going-concern financial position of the plan, long-term return expectations and the risks associated with key asset classes as well as the relationships of returns on key asset classes with each other, inflation and interest rates. When advantageous and with due consideration, derivative instruments may be utilized, provided the total value of the underlying assets represented by financial derivatives, excluding currency forwards, is limited to 30% of the market value of the fund. When investing in foreign securities, the plans are exposed to foreign currency risk; the effect of which is included in the valuation of the foreign securities. At December 31, 2017 the plans were 40% exposed to the U.S. dollar, 11% exposed to European currencies, and 7% exposed to various other currencies. At December 31, 2017 , fund assets consisted primarily of listed stocks and bonds, including 107,330 of the Company’s Common Shares ( 2016 – 109,630 ) at a market value of $25 million ( 2016 – $21 million ) and Unsecured Notes issued by the Company at a par value of $1 million ( 2016 – $3 million ) and a market value of $1 million ( 2016 – $3 million ). Cash flows The Company contributed the following to its different pension plans: (in millions of Canadian dollars) 2017 2016 2015 Canadian registered and U.S. qualified DB pension plans $ 33 $ 36 $ 69 Canadian non-registered supplemental pension plan 13 12 12 DC plans 9 9 9 Total Company pension contribution $ 55 $ 57 $ 90 In addition, the Company made payments directly to employees, their beneficiaries or estates or to third-party benefit administrators of $34 million in 2017 (2016 – $30 million ; 2015 – $33 million ) with respect to other benefits. Estimated future benefit payments The estimated future defined benefit pension and other benefit payments to be paid by the plans for each of the next five years and the subsequent five-year period are as follows: (in millions of Canadian dollars) Pensions Other benefits 2018 $ 609 $ 33 2019 614 31 2020 620 31 2021 625 31 2022 631 30 2023 – 2027 3,220 146 The benefit payments from the Canadian registered and U.S. qualified DB pension plans are payable from their respective pension funds. Benefit payments from the supplemental pension plan and from the other benefits plans are payable directly from the Company. Defined contribution plan Canadian non-unionized employees hired prior to July 1, 2010 had the option to participate in the Canadian DC plan. All Canadian non-unionized employees hired after such date must participate in this plan. Employee contributions are based on a percentage of salary. The Company matches employee contributions to a maximum percentage each year. Effective July 1, 2010, a new U.S. DC plan was established. All U.S. non-unionized employees hired after such date must participate in this plan. Employees do not contribute to the plan. The Company annually contributes a percentage of salary. The DC plans provide a pension based on total employee and employer contributions plus investment income earned on those contributions. In 2017 , the net cost of the DC plans, which generally equals the employer’s required contribution, was $9 million ( 2016 – $9 million ; 2015 – $9 million ). Contributions to multi-employer plans Some of the Company’s unionized employees in the U.S. are members of a U.S. national multi-employer benefit plan. Contributions made by the Company to this plan in 2017 in respect of post-retirement medical benefits were $5 million ( 2016 – $4 million ; 2015 – $4 million

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-based compensation At December 31, 2017 , the Company had several stock-based compensation plans, including a stock option plan, various cash settled liability plans and an employee share purchase plan. These plans resulted in an expense in 2017 of $35 million ( 2016 – $51 million ; 2015 – $66 million ). Effective January 31, 2017, Mr. E. Hunter Harrison resigned from all positions held by him at the Company, including as the Company’s Chief Executive Officer and as a member of the Board of Directors of the Company. In connection with Mr. Harrison’s resignation, the Company entered into a separation agreement with Mr. Harrison. Under the terms of the separation agreement, the Company agreed to a limited waiver of Mr. Harrison’s non-competition and non-solicitation obligations. Effective January 31, 2017, pursuant to the separation agreement, Mr. Harrison forfeited certain pension and post-retirement benefits and agreed to the surrender for cancellation of 22,514 performance share units ("PSU"), 68,612 deferred share units ("DSU"), and 752,145 stock options. As a result of this agreement, the Company recognized a recovery of $51 million in "Compensation and benefits" in the first quarter of 2017. Of this amount, $27 million related to a recovery from cancellation of certain pension benefits. A. Stock Option Plan The following table summarizes the Company’s stock option plan as at December 31, 2017 : Options outstanding Nonvested options Number of Weighted Number of Weighted Outstanding, January 1, 2017 2,450,082 $ 121.95 850,167 $ 44.49 Granted 369,980 $ 193.13 369,980 $ 45.78 Exercised (536,291 ) $ 84.93 N/A N/A Vested N/A N/A (328,265 ) $ 42.97 Forfeited (803,796 ) $ 120.97 (208,955 ) $ 47.21 Expired (700 ) $ 62.56 N/A N/A Outstanding, December 31, 2017 1,479,275 $ 150.64 682,927 $ 45.46 Vested or expected to vest at December 31, 2017 (1) 1,419,564 $ 149.05 N/A N/A Exercisable, December 31, 2017 796,348 $ 119.32 N/A N/A (1) As at December 31, 2017 , the weighted average remaining term of vested or expected to vest options was 7.0 years with an aggregate intrinsic value of $114 million . The following table provides the number of stock options outstanding and exercisable as at December 31, 2017 by range of exercise price and their related intrinsic aggregate value, and for options outstanding, the weighted-average years to expiration. The table also provides the aggregate intrinsic value for in-the-money stock options, which represents the amount that would have been received by option holders had they exercised their options on December 31, 2017 at the Company’s closing stock price of $229.66 . Options outstanding Options exercisable Range of exercise prices Number of Weighted Weighted Aggregate Number of Weighted Aggregate $36.29 – $117.48 416,270 3.7 $ 84.50 $ 60 416,270 $ 84.50 $ 60 $117.49 – $165.95 359,997 6.8 $ 141.38 $ 32 200,362 $ 128.43 $ 20 $165.96 – $190.42 415,914 6.1 $ 182.48 $ 20 106,458 $ 169.28 $ 6 $190.43 – $222.88 287,094 6.7 $ 212.05 $ 5 73,258 $ 219.60 $ 1 Total (1) 1,479,275 5.7 $ 150.64 $ 117 796,348 $ 119.32 $ 87 (1) As at December 31, 2017 , the total number of in-the-money stock options outstanding was 1,479,275 with a weighted-average exercise price of $150.64 . The weighted-average years to expiration of exercisable stock options is 4.9 years . Pursuant to the employee plan, options may be exercised upon vesting, which is between 12 months and 60 months after the grant date, and will expire after seven years. Certain stock options granted in 2017 vest upon the achievement of specific performance criteria. Under the fair value method, the fair value of options at the grant date was approximately $17 million for options issued in 2017 ( 2016 – $16 million ; 2015 – $18 million ). The weighted average fair value assumptions were approximately: 2017 2016 2015 Expected option life (years) (1) 5.48 5.25 5.25 Risk-free interest rate (2) 1.85 % 1.21 % 1.10 % Expected stock price volatility (3) 27 % 27 % 26 % Expected annual dividends per share (4) $ 2.0010 $ 1.4000 $ 1.4000 Estimated forfeiture rate (5) 2.8 % 2.0 % 1.2 % Weighted average grant date fair value of options granted during the year $ 45.78 $ 39.01 $ 55.28 (1) Represents the period of time that awards are expected to be outstanding. Historical data on exercise behaviour or, when available, specific expectations regarding future exercise behaviour were used to estimate the expected life of the option. (2) Based on the implied yield available on zero-coupon government issues with an equivalent remaining term at the time of the grant. (3) Based on the historical stock price volatility of the Company’s stock over a period commensurate with the expected term of the option. (4) Determined by the current annual dividend at the time of grant. The Company does not employ different dividend yields throughout the contractual term of the option. On May 10, 2017, the Company announced an increase in its quarterly dividend to $0.5625 per share, representing $2.2500 on an annual basis. (5) The Company estimated forfeitures based on past experience. The rate is monitored on a periodic basis. In 2017 , the expense for stock options (regular and performance) was $3 million ( 2016 – $14 million ; 2015 – $15 million ). At December 31, 2017 , there was $9 million of total unrecognized compensation related to stock options which is expected to be recognized over a weighted-average period of approximately 1.3 years. The total fair value of shares vested for the stock option plan during 2017 was $14 million ( 2016 – $15 million ; 2015 – $17 million ). The following table provides information related to all options exercised in the stock option plan during the years ended December 31 : (in millions of Canadian dollars) 2017 2016 2015 Total intrinsic value $ 36 $ 30 $ 72 Cash received by the Company upon exercise of options $ 45 $ 21 $ 43 B. Other Share-based Plans Performance share units plan During 2017 , the Company issued 134,991 PSUs with a grant date fair value of approximately $27 million . These units attract dividend equivalents in the form of additional units based on the dividends paid on the Company’s Common Shares. PSUs vest and are settled in cash or in CP Common Shares, approximately 3 years after the grant date, contingent upon CP’s performance (performance factor). Grant recipients who are eligible to retire and have provided six months of service during the performance period are entitled to the full award. The fair value of PSUs is measured periodically until settlement, using a lattice-based valuation model. The performance period for PSUs issued in 2017 is January 1, 2017 to December 31, 2019, and the performance factors for these PSUs are Return on Invested Capital ("ROIC"), Total Shareholder Return ("TSR") compared to the S&P/TSX Capped Industrial index, and TSR compared to S&P 1500 Road and Rail index. The performance period for PSUs issued in 2016 is January 1, 2016 to December 31, 2018, and the performance factors for these PSUs are Operating Ratio, ROIC, TSR compared to the S&P/TSX60 index, and TSR compared to Class I railways. The performance period for the PSUs issued in 2015 was January 1, 2015 to December 31, 2017. The performance factors for these PSUs were Operating Ratio, ROIC, TSR compared to the S&P/TSX60 index, and TSR compared to Class I railways. The resulting estimated payout was 160% on 82,673 total outstanding awards representing a total fair value of $30 million at December 31, 2017 , calculated using the Company's average share price using the last 30 trading days preceding December 31, 2017 . The performance period for the PSUs issued in 2014 was January 1, 2014 to December 31, 2016. The performance factors for these PSUs were Operating Ratio, Free cash flow, TSR compared to the S&P/TSX60 index, and TSR compared to Class I railways. The resulting payout was 118% of the Company's average share price that was calculated using the last 30 trading days preceding December 31, 2016. In the first quarter of 2017, payouts occurred on the total outstanding awards, including dividends reinvested, totalling $31 million on 133,728 outstanding awards. The following table summarizes information related to the Company’s PSUs as at December 31 : 2017 2016 Outstanding, January 1 373,593 348,276 Granted 134,991 147,157 Units, in lieu of dividends 3,571 4,010 Settled (133,728 ) (83,466 ) Forfeited (44,399 ) (42,384 ) Outstanding, December 31 334,028 373,593 In 2017 , the expense for PSUs was $30 million ( 2016 – $29 million ; 2015 – $55 million ). At December 31, 2017 , there was $20 million of total unrecognized compensation related to PSUs which is expected to be recognized over a weighted-average period of approximately 1.5 years. Deferred share units plan The Company established the DSU plan as a means to compensate and assist in attaining share ownership targets set for certain key employees and Directors. A DSU entitles the holder to receive, upon redemption, a cash payment equivalent to the Company's average share price using the 10 trading days prior to redemption. DSUs vest over various periods of up to 48 months and are only redeemable for a specified period after employment is terminated. Senior managers may elect to receive DSUs in lieu of annual bonus cash payments in the bonus deferral program. In addition, senior managers will be granted a 25% company match of DSUs when deferring cash to DSUs to meet ownership targets. The election to receive eligible payments in DSUs is no longer available to a participant when the value of the participant’s DSUs is sufficient to meet the Company’s stock ownership guidelines. Senior managers have 5 years to meet their ownership targets. An expense for DSUs is recognized over the vesting period for both the initial subscription price and the change in value between reporting periods. The following table summarizes information related to the DSUs as at December 31 : 2017 2016 Outstanding, January 1 234,036 318,176 Granted 23,932 31,069 Units, in lieu of dividends 1,969 2,798 Settled (33,682 ) (87,996 ) Forfeited (69,708 ) (30,011 ) Outstanding, December 31 156,547 234,036 During 2017 , the Company granted 23,932 DSUs with a grant date fair value of approximately $5 million . In 2017 , the recovery for DSUs was $3 million ( 2016 – $2 million expense; 2015 – $10 million recovery). At December 31, 2017 , there was $1 million of total unrecognized compensation related to DSUs which is expected to be recognized over a weighted-average period of approximately 1.4 years. Summary of share based liabilities paid The following table summarizes the total share based liabilities paid for each of the years ended December 31 : (in millions of Canadian dollars) 2017 2016 2015 Plan DSUs $ 6 $ 17 $ 3 PSUs 31 31 79 Other 2 — 8 Total $ 39 $ 48 $ 90 C. Employee share purchase plan The Company has an employee share purchase plan whereby both employee and the Company contributions are used to purchase shares on the open market for employees. The Company’s contributions are expensed over the one year vesting period. Under the plan, the Company matches $1 for every $3 contributed by employees up to a maximum employee contribution of 6% of annual salary. The total number of shares purchased in 2017 on behalf of participants, including the Company's contributions, was 130,041 ( 2016 – 140,560 ; 2015 – 131,703 ). In 2017 , the Company’s contributions totalled $5 million ( 2016 – $5 million ; 2015 – $5 million ) and the related expense was $4 million ( 2016 – $5 million ; 2015 – $4 million

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Variable Interest Entities	Variable interest entities The Company leases equipment from certain trusts, which have been determined to be variable interest entities financed by a combination of debt and equity provided by unrelated third parties. The lease agreements, which are classified as operating leases, have fixed price purchase options which create the Company’s variable interests and result in the trusts being considered variable interest entities. Maintaining and operating the leased assets according to specific contractual obligations outlined in the terms of the lease agreements and industry standards is the Company’s responsibility. The rigor of the contractual terms of the lease agreements and industry standards are such that the Company has limited discretion over the maintenance activities associated with these assets. As such, the Company concluded these terms do not provide the Company with the power to direct the activities of the variable interest entities in a way that has a significant impact on the entities’ economic performance. The financial exposure to the Company as a result of its involvement with the variable interest entities is equal to the fixed lease payments due to the trusts. In 2017 , lease payments after tax were $10 million . Future minimum lease payments, before tax, of $177 million will be payable over the next 13 years . The Company does not guarantee the residual value of the assets to the lessor; however, it must deliver to the lessor the assets in good operating condition, subject to normal wear and tear, at the end of the lease term.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and contingencies In the normal course of its operations, the Company becomes involved in various legal actions, including claims relating to injuries and damage to property. The Company maintains provisions it considers to be adequate for such actions. While the final outcome with respect to actions outstanding or pending at December 31, 2017 , cannot be predicted with certainty, it is the opinion of management that their resolution will not have a material adverse effect on the Company’s financial position or results of operations. Commitments At December 31, 2017 , the Company had committed to total future capital expenditures amounting to $632 million and operating expenditures relating to supplier purchase obligations, such as locomotive maintenance and overhaul agreements, as well as agreements to purchase other goods and services amounting to approximately $1.7 billion for the years 2018 – 2032 , of which CP estimates approximately $1.4 billion will be incurred in the next five years. As at December 31, 2017 , the Company’s commitments under operating leases were estimated at $351 million in aggregate, with minimum annual payments in each of the next five years and thereafter as follows: (in millions of Canadian dollars) Operating 2018 $ 71 2019 57 2020 45 2021 38 2022 31 Thereafter 109 Total minimum lease payments $ 351 Expenses for operating leases for the year ended December 31, 2017 , were $104 million ( 2016 – $111 million ; 2015 – $127 million ). Legal proceedings related to Lac-Mégantic rail accident On July 6, 2013, a train carrying petroleum crude oil operated by Montreal Maine and Atlantic Railway (“MMAR”) or a subsidiary, Montreal Maine & Atlantic Canada Co. (“MMAC” and collectively the “MMA Group”), derailed in Lac-Mégantic, Québec. The derailment occurred on a section of railway owned and operated by the MMA Group. The previous day CP had interchanged the train to the MMA Group, and after the interchange, the MMA Group exclusively controlled the train. In the wake of the derailment, MMAC sought court protection in Canada under the Companies’ Creditors Arrangement Act, R.S.C., 1985, c. C-36 and MMAR filed for bankruptcy in the United States. Plans of arrangement have been approved in both Canada and the U.S. (the “Plans”). These Plans provide for the distribution of a fund of approximately $440 million amongst those claiming derailment damages. A number of legal proceedings, set out below, were commenced after the derailment in Canada and/or in the U.S. against CP and others: (1) Québec's Minister of Sustainable Development, Environment, Wildlife and Parks (the "Minister") ordered various parties, including CP, to clean up the derailment site (the “Cleanup Order”). CP appealed the Cleanup Order to the Administrative Tribunal of Québec (the “TAQ”). The Minister subsequently served a Notice of Claim seeking $95 million for compensation spent on cleanup. CP filed a contestation of the Notice of Claim with the TAQ (the “TAQ Proceeding”). CP and the Minister agreed to stay the TAQ Proceedings pending the outcome of the Province of Québec's action, described in item #2 below. (2) Québec’s Attorney General sued CP in the Québec Superior Court initially claiming $409 million in damages, which claim was amended and reduced to $315 million (the “Province’s Action”). The Province’s Action alleges that CP exercised custody or control over the petroleum crude oil until its delivery to Irving Oil, that CP was negligent in its custody and control of the petroleum crude oil and that therefore CP is jointly and severally liable with third parties responsible for the derailment and vicariously liable for the acts and omissions of MMAC. (3) A class action in the Québec Superior Court on behalf of persons and entities residing in, owning or leasing property in, operating a business in or physically present in Lac-Mégantic at the time of the derailment (the “Class Action”) was certified against CP, MMAC and the train conductor, Mr. Thomas Harding. The Class Action seeks unquantified damages, including for wrongful death, personal injury, and property damage arising from the derailment. All known wrongful death claimants in the Class Action have opted out and, by court order, cannot re-join the Class Action. (4) Eight subrogated insurers sued CP in the Québec Superior Court initially claiming approximately $16 million in damages, which claim was amended and reduced to $14 million (the “Promutuel Action”) and two additional subrogated insurers sued CP in the Québec Superior Court claiming approximately $3 million in damages (the “Royal Action”). Both Actions contain essentially the same allegations as the Province’s Action. The lawsuits do not identify the parties to which the insurers are subrogated, and therefore the extent to which these claims overlap with the proof of claims process under the Plans is difficult to determine at this stage. The Royal Action has been stayed pending the determination of the consolidated proceedings described below. The Province’s Action, the Class Action and the Promutuel Action have been consolidated and will proceed together through the litigation process in the Québec Superior Court. While each Action will remain a separate legal proceeding, there will be a trial to determine liability issues commencing mid-September 2019, and subsequently, if necessary, a trial to determine damages issues. (5) An adversary proceeding filed by the MMAR U.S. estate representative (“Estate Representative”) in Maine accuses CP of failing to abide by certain regulations (the “Adversary Proceeding”). The Estate Representative alleges that CP should not have moved the petroleum crude oil train because an inaccurate classification by the shipper was or should have been known. The Estate Representative seeks damages for MMAR’s business value (as yet unquantified) allegedly destroyed by the derailment. (6) A class action and mass tort action on behalf of Lac-Mégantic residents and wrongful death representatives commenced in Texas and wrongful death and personal injury actions commenced in Illinois and Maine against CP were all removed to and consolidated in Maine (the “Maine Actions”). The Maine Actions allege that CP negligently misclassified and mis-packaged the petroleum crude oil being shipped. On CP’s motion, the Maine Actions were dismissed by the Court on several grounds. The plaintiffs are appealing the dismissal decision. (7) The Trustee (the “WD Trustee”) for the wrongful death trust (the “WD Trust”), as defined and established by the Estate Representative under the Plans, asserts Carmack Amendment claims against CP in North Dakota federal court (the “Carmack Claims”). The WD Trustee seeks to recover approximately $6 million for damaged rail cars, and the settlement amounts the consignor and the consignee paid to the bankruptcy estates, alleged to be $110 million and $60 million , respectively. On CP’s motion, the federal court in North Dakota dismissed the Carmack Claims. The WD Trustee is appealing the dismissal decision.

Guarantees

Guarantees	12 Months Ended
	Dec. 31, 2017
Guarantees [Abstract]
Guarantees	Guarantees In the normal course of operating the railway, the Company enters into contractual arrangements that involve providing certain guarantees, which extend over the term of the contracts. These guarantees include, but are not limited to: • residual value guarantees on operating lease commitments of $6 million at December 31, 2017 ; • guarantees to pay other parties in the event of the occurrence of specified events, including damage to equipment, in relation to assets used in the operation of the railway through operating leases, rental agreements, easements, trackage, and interline agreements; and • indemnifications of certain tax-related payments incurred by lessors and lenders. The maximum amount that could be payable under these guarantees, excluding residual value guarantees, cannot be reasonably estimated due to the nature of certain of these guarantees. All or a portion of amounts paid under guarantees to other parties in the event of the occurrence of specified events could be recoverable from other parties or through insurance. The Company has accrued for all guarantees that it expects to pay. At December 31, 2017 , these accruals amounted to $9 million ( 2016 – $5 million ), and are recorded in “Accounts payable and accrued liabilities”. Indemnifications Pursuant to a trust and custodial services agreement with the trustee of the Canadian Pacific Railway Company Pension Plan, the Company has undertaken to indemnify and save harmless the trustee, to the extent not paid by the fund, from any and all taxes, claims, liabilities, damages, costs, and expenses arising out of the performance of the trustee’s obligations under the agreement, except as a result of misconduct by the trustee. The indemnity includes liabilities, costs, or expenses relating to any legal reporting or notification obligations of the trustee with respect to the defined benefit and defined contribution options of the pension plans, or otherwise with respect to the assets of the pension plans that are not part of the fund. The indemnity survives the termination or expiry of the agreement with respect to claims and liabilities arising prior to the termination or expiry. At December 31, 2017

Segmented and Geographic Inform

Segmented and Geographic Information	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Segmented and Geographical Information	Segmented and geographic information Operating segment The Company operates in only one operating segment: rail transportation. Operating results by geographic areas, railway corridors or other lower-level components or units of operation are not reviewed by the Company’s chief operating decision-maker to make decisions about the allocation of resources to, or the assessment of performance of, such geographic areas, corridors, components or units of operation. In the years ended December 31, 2017 , 2016 , and 2015 , no one customer comprised more than 10% of total revenues and accounts receivable. Geographic information (in millions of Canadian dollars) Canada United States Total 2017 Revenues $ 4,667 $ 1,887 $ 6,554 Long-term assets excluding financial instruments and pension assets $ 11,505 $ 5,947 $ 17,452 2016 Revenues $ 4,473 $ 1,759 $ 6,232 Long-term assets excluding financial instruments and pension assets $ 11,000 $ 6,121 $ 17,121 2015 Revenues $ 4,662 $ 2,050 $ 6,712 Long-term assets excluding financial instruments and pension assets $ 10,630 $ 6,068 $ 16,698

Selected Quarterly Data (Unaudi

Selected Quarterly Data (Unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Data (Unaudited)	Selected quarterly data (unaudited) For the quarter ended 2017 2016 (in millions of Canadian dollars, except per share data) Dec. 31 Sep. 30 Jun. 30 Mar. 31 Dec. 31 Sep. 30 Jun. 30 Mar. 31 Total revenues $ 1,713 $ 1,595 $ 1,643 $ 1,603 $ 1,637 $ 1,554 $ 1,450 $ 1,591 Operating income 753 690 679 671 717 657 551 653 Net income 984 510 480 431 384 347 328 540 Basic earnings per share (1) $ 6.79 $ 3.50 $ 3.28 $ 2.94 $ 2.63 $ 2.35 $ 2.16 $ 3.53 Diluted earnings per share (1) 6.77 3.50 3.27 2.93 2.61 2.34 2.15 3.51 (1)

Condensed Consolidating Financi

Condensed Consolidating Financial Information	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Condensed Consolidating Financial Information	Condensed consolidating financial information Canadian Pacific Railway Company, a 100%-owned subsidiary of Canadian Pacific Railway Limited (“CPRL”), is the issuer of certain debt securities, which are fully and unconditionally guaranteed by CPRL. The following tables present condensed consolidating financial information (“CCFI”) in accordance with Rule 3-10(c) of Regulation S-X. Investments in subsidiaries are accounted for under the equity method when presenting the CCFI. YEAR ENDED DECEMBER 31, 2017 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Revenues Freight $ — $ 4,516 $ 1,859 $ — $ 6,375 Non-freight — 140 372 (333 ) 179 Total revenues — 4,656 2,231 (333 ) 6,554 Operating expenses Compensation and benefits — 601 427 7 1,035 Fuel — 522 155 — 677 Materials — 134 41 15 190 Equipment rents — 143 (1 ) — 142 Depreciation and amortization — 400 261 — 661 Purchased services and other — 826 585 (355 ) 1,056 Total operating expenses — 2,626 1,468 (333 ) 3,761 Operating income — 2,030 763 — 2,793 Less: Other income and charges (33 ) (149 ) 4 — (178 ) Net interest (income) expense (12 ) 517 (32 ) — 473 Income before income tax expense and equity in net earnings of subsidiaries 45 1,662 791 — 2,498 Less: Income tax expense (recovery) 7 475 (389 ) — 93 Add: Equity in net earnings of subsidiaries 2,367 1,180 — (3,547 ) — Net income $ 2,405 $ 2,367 $ 1,180 $ (3,547 ) $ 2,405 YEAR ENDED DECEMBER 31, 2016 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Revenues Freight $ — $ 4,332 $ 1,728 $ — $ 6,060 Non-freight — 134 386 (348 ) 172 Total revenues — 4,466 2,114 (348 ) 6,232 Operating expenses Compensation and benefits — 749 434 6 1,189 Fuel — 458 109 — 567 Materials — 130 32 18 180 Equipment rents — 204 (31 ) — 173 Depreciation and amortization — 422 218 — 640 Purchased services and other — 673 604 (372 ) 905 Total operating expenses — 2,636 1,366 (348 ) 3,654 Operating income — 1,830 748 — 2,578 Less: Other income and charges (40 ) (34 ) 29 — (45 ) Net interest expense (income) 1 493 (23 ) — 471 Income before income tax expense and equity in net earnings of subsidiaries 39 1,371 742 — 2,152 Less: Income tax expense 6 337 210 — 553 Add: Equity in net earnings of subsidiaries 1,566 532 — (2,098 ) — Net income $ 1,599 $ 1,566 $ 532 $ (2,098 ) $ 1,599 YEAR ENDED DECEMBER 31, 2015 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Revenues Freight $ — $ 4,532 $ 2,020 $ — $ 6,552 Non-freight — 128 363 (331 ) 160 Total revenues — 4,660 2,383 (331 ) 6,712 Operating expenses Compensation and benefits — 943 428 — 1,371 Fuel — 549 159 — 708 Materials — 148 36 — 184 Equipment rents — 181 (7 ) — 174 Depreciation and amortization — 411 184 — 595 Purchased services and other — 711 680 (331 ) 1,060 Gain on sale of Delaware & Hudson South — — (68 ) — (68 ) Total operating expenses — 2,943 1,412 (331 ) 4,024 Operating income — 1,717 971 — 2,688 Less: Other income and charges 84 322 (71 ) — 335 Net interest (income) expense (5 ) 447 (48 ) — 394 (Loss) income before income tax expense and equity in net earnings of subsidiaries (79 ) 948 1,090 — 1,959 Less: Income tax (recovery) expense (21 ) 303 325 — 607 Add: Equity in net earnings of subsidiaries $ 1,410 $ 765 $ — $ (2,175 ) $ — Net income $ 1,352 $ 1,410 $ 765 $ (2,175 ) $ 1,352 YEAR ENDED DECEMBER 31, 2017 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Net income $ 2,405 $ 2,367 $ 1,180 $ (3,547 ) $ 2,405 Net gain (loss) in foreign currency translation adjustments, net of hedging activities — 318 (294 ) — 24 Change in derivatives designated as cash flow — 19 — — 19 Change in pension and post-retirement defined — 82 (2 ) — 80 Other comprehensive income (loss) before income taxes — 419 (296 ) — 123 Income tax (expense) recovery on above items — (66 ) 1 — (65 ) Equity accounted investments 58 (295 ) — 237 — Other comprehensive income (loss) 58 58 (295 ) 237 58 Comprehensive income $ 2,463 $ 2,425 $ 885 $ (3,310 ) $ 2,463 YEAR ENDED DECEMBER 31, 2016 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Net income $ 1,599 $ 1,566 $ 532 $ (2,098 ) $ 1,599 Net gain (loss) in foreign currency translation adjustments, net of hedging activities — 149 (131 ) — 18 Change in derivatives designated as cash flow — (2 ) — — (2 ) Change in pension and post-retirement defined — (443 ) 9 — (434 ) Other comprehensive loss before income taxes — (296 ) (122 ) — (418 ) Income tax recovery (expense) on above items — 99 (3 ) — 96 Equity accounted investments (322 ) (125 ) — 447 — Other comprehensive loss (322 ) (322 ) (125 ) 447 (322 ) Comprehensive income $ 1,277 $ 1,244 $ 407 $ (1,651 ) $ 1,277 YEAR ENDED DECEMBER 31, 2015 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Net income $ 1,352 $ 1,410 $ 765 $ (2,175 ) $ 1,352 Net (loss) gain in foreign currency translation adjustments, net of hedging activities — (757 ) 671 — (86 ) Change in derivatives designated as cash flow — (69 ) — — (69 ) Change in pension and post-retirement defined — 1,061 (2 ) — 1,059 Other comprehensive income before income taxes — 235 669 — 904 Income tax (expense) recovery on above items — (163 ) 1 — (162 ) Equity accounted investments 742 670 — (1,412 ) — Other comprehensive income 742 742 670 (1,412 ) 742 Comprehensive income $ 2,094 $ 2,152 $ 1,435 $ (3,587 ) $ 2,094 AS AT DECEMBER 31, 2017 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Assets Current assets Cash and cash equivalents $ — $ 241 $ 97 $ — $ 338 Accounts receivable, net — 508 179 — 687 Accounts receivable, intercompany 97 153 215 (465 ) — Short-term advances to affiliates 500 1,004 4,996 (6,500 ) — Materials and supplies — 120 32 — 152 Other current assets — 31 66 — 97 597 2,057 5,585 (6,965 ) 1,274 Long-term advances to affiliates 590 — 410 (1,000 ) — Investments — 27 155 — 182 Investments in subsidiaries 10,623 12,122 — (22,745 ) — Properties — 8,982 8,034 — 17,016 Goodwill and intangible assets — — 187 — 187 Pension asset — 1,407 — — 1,407 Other assets — 56 13 — 69 Deferred income taxes 3 — — (3 ) — Total assets $ 11,813 $ 24,651 $ 14,384 $ (30,713 ) $ 20,135 Liabilities and shareholders’ equity Current liabilities Accounts payable and accrued liabilities $ 82 $ 844 $ 312 $ — $ 1,238 Accounts payable, intercompany 3 309 153 (465 ) — Short-term advances from affiliates 5,291 1,185 24 (6,500 ) — Long-term debt maturing within one year — 746 — — 746 5,376 3,084 489 (6,965 ) 1,984 Pension and other benefit liabilities — 672 77 — 749 Long-term advances from affiliates — 1,000 — (1,000 ) — Other long-term liabilities — 108 123 — 231 Long-term debt — 7,362 51 — 7,413 Deferred income taxes — 1,802 1,522 (3 ) 3,321 Total liabilities 5,376 14,028 2,262 (7,968 ) 13,698 Shareholders’ equity Share capital 2,032 1,037 6,730 (7,767 ) 2,032 Additional paid-in capital 43 1,643 259 (1,902 ) 43 Accumulated other comprehensive (loss) income (1,741 ) (1,742 ) 417 1,325 (1,741 ) Retained earnings 6,103 9,685 4,716 (14,401 ) 6,103 6,437 10,623 12,122 (22,745 ) 6,437 Total liabilities and shareholders’ equity $ 11,813 $ 24,651 $ 14,384 $ (30,713 ) $ 20,135 AS AT DECEMBER 31, 2016 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Assets Current assets Cash and cash equivalents $ — $ 100 $ 64 $ — $ 164 Accounts receivable, net — 435 156 — 591 Accounts receivable, intercompany 90 113 206 (409 ) — Short-term advances to affiliates 500 692 4,035 (5,227 ) — Materials and supplies — 150 34 — 184 Other current assets — 38 32 — 70 590 1,528 4,527 (5,636 ) 1,009 Long-term advances to affiliates 1 — 91 (92 ) — Investments — 47 147 — 194 Investments in subsidiaries 8,513 10,249 — (18,762 ) — Properties — 8,756 7,933 — 16,689 Goodwill and intangible assets — — 202 — 202 Pension asset — 1,070 — — 1,070 Other assets 1 48 8 — 57 Deferred income taxes 11 — — (11 ) — Total assets $ 9,116 $ 21,698 $ 12,908 $ (24,501 ) $ 19,221 Liabilities and shareholders’ equity Current liabilities Accounts payable and accrued liabilities $ 73 $ 945 $ 304 $ — $ 1,322 Accounts payable, intercompany 14 292 103 (409 ) — Short-term advances from affiliates 4,403 816 8 (5,227 ) — Long-term debt maturing within one year — 25 — — 25 4,490 2,078 415 (5,636 ) 1,347 Pension and other benefit liabilities — 658 76 — 734 Long-term advances from affiliates — 92 — (92 ) — Other long-term liabilities — 152 132 — 284 Long-term debt — 8,605 54 — 8,659 Deferred income taxes — 1,600 1,982 (11 ) 3,571 Total liabilities 4,490 13,185 2,659 (5,739 ) 14,595 Shareholders’ equity Share capital 2,002 1,037 5,823 (6,860 ) 2,002 Additional paid-in capital 52 1,638 298 (1,936 ) 52 Accumulated other comprehensive (loss) income (1,799 ) (1,799 ) 712 1,087 (1,799 ) Retained earnings 4,371 7,637 3,416 (11,053 ) 4,371 4,626 8,513 10,249 (18,762 ) 4,626 Total liabilities and shareholders’ equity $ 9,116 $ 21,698 $ 12,908 $ (24,501 ) $ 19,221 YEAR ENDED DECEMBER 31, 2017 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Cash provided by operating activities $ 338 $ 1,334 $ 989 $ (479 ) $ 2,182 Investing activities Additions to properties — (950 ) (390 ) — (1,340 ) Proceeds from sale of properties and other assets — 29 13 — 42 Advances to affiliates (590 ) (550 ) (1,528 ) 2,668 — Repayment of advances to affiliates — 242 243 (485 ) — Capital contributions to affiliates — (1,039 ) — 1,039 — Repurchase of share capital from affiliates — 156 — (156 ) — Other — 5 (2 ) — 3 Cash used in investing activities (590 ) (2,107 ) (1,664 ) 3,066 (1,295 ) Financing activities Dividends paid (310 ) (310 ) (169 ) 479 (310 ) Issuance of share capital — — 1,039 (1,039 ) — Return of share capital to affiliates — — (156 ) 156 — Issuance of CP Common Shares 45 — — — 45 Purchase of CP Common Shares (381 ) — — — (381 ) Repayment of long-term debt, excluding commercial paper — (32 ) — — (32 ) Advances from affiliates 1,383 1,285 — (2,668 ) — Repayment of advances from affiliates (485 ) — — 485 — Settlement of forward starting swaps — (22 ) — — (22 ) Cash provided by (used in) financing activities 252 921 714 (2,587 ) (700 ) Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents — (7 ) (6 ) — (13 ) Cash position Increase in cash and cash equivalents — 141 33 — 174 Cash and cash equivalents at beginning of year — 100 64 — 164 Cash and cash equivalents at end of year $ — $ 241 $ 97 $ — $ 338 YEAR ENDED DECEMBER 31, 2016 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Cash provided by operating activities $ 255 $ 1,424 $ 879 $ (469 ) $ 2,089 Investing activities Additions to properties — (728 ) (454 ) — (1,182 ) Proceeds from sale of properties and other assets — 102 14 — 116 Advances to affiliates — (664 ) (539 ) 1,203 — Repayment of advances to affiliates — 222 — (222 ) — Capital contributions to affiliates — (472 ) — 472 — Repurchase of share capital from affiliates — 8 — (8 ) — Other — — (3 ) — (3 ) Cash used in investing activities — (1,532 ) (982 ) 1,445 (1,069 ) Financing activities Dividends paid (255 ) (255 ) (214 ) 469 (255 ) Issuance of share capital — — 472 (472 ) — Return of share capital to affiliates — — (8 ) 8 — Issuance of CP Common Shares 21 — — — 21 Purchase of CP Common Shares (1,210 ) — — — (1,210 ) Repayment of long-term debt, excluding commercial paper — (24 ) (14 ) — (38 ) Net repayment of commercial paper — (8 ) — — (8 ) Advances from affiliates 1,189 — 14 (1,203 ) — Repayment of advances from affiliates — — (222 ) 222 — Other — (3 ) — — (3 ) Cash (used in) provided by financing activities (255 ) (290 ) 28 (976 ) (1,493 ) Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents — (4 ) (9 ) — (13 ) Cash position Decrease in cash and cash equivalents — (402 ) (84 ) — (486 ) Cash and cash equivalents at beginning of year — 502 148 — 650 Cash and cash equivalents at end of year $ — $ 100 $ 64 $ — $ 164 YEAR ENDED DECEMBER 31, 2015 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Cash provided by operating activities $ 2,283 $ 1,650 $ 1,074 $ (2,548 ) $ 2,459 Investing activities Additions to properties — (766 ) (756 ) — (1,522 ) Proceeds from the sale of Delaware & Hudson South — — 281 — 281 Proceeds from sale of properties and other assets — 103 11 — 114 Advances to affiliates (1,133 ) (311 ) (1,820 ) 3,264 — Repayment of advances to affiliates — 804 1,000 (1,804 ) — Capital contributions to affiliates — (1,655 ) — 1,655 — Repurchase of share capital from affiliates — 1,210 — (1,210 ) — Other — 6 (2 ) — 4 Cash used in investing activities (1,133 ) (609 ) (1,286 ) 1,905 (1,123 ) Financing activities Dividends paid (226 ) (2,272 ) (276 ) 2,548 (226 ) Issuance of share capital — — 1,655 (1,655 ) — Return of share capital to affiliates — — (1,210 ) 1,210 — Issuance of CP Common Shares 43 — — — 43 Purchase of CP Common Shares (2,787 ) — — — (2,787 ) Issuance of long-term debt, excluding commercial paper — 3,411 — — 3,411 Repayment of long-term debt, excluding commercial paper — (461 ) (44 ) — (505 ) Net repayment of commercial paper — (893 ) — — (893 ) Advances from affiliates 1,820 500 944 (3,264 ) — Repayment of advances from affiliates — (1,000 ) (804 ) 1,804 — Cash (used in) provided by financing activities (1,150 ) (715 ) 265 643 (957 ) Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents — 24 21 — 45 Cash position Increase in cash and cash equivalents — 350 74 — 424 Cash and cash equivalents at beginning of year — 152 74 — 226 Cash and cash equivalents at end of year $ — $ 502 $ 148 $ — $ 650

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2017
Valuation and Qualifying Accounts [Abstract]
Valuation and Qualifying Accounts	Schedule II – Valuation and Qualifying Accounts (in millions of Canadian dollars) Beginning balance at January 1 Additions charged to expenses Payments and other reductions Impact of FX Ending Accruals for personal injury and other claims liabilities (1) 2015 $ 150 $ 79 $ (102 ) $ 6 $ 133 2016 $ 133 $ 67 $ (71 ) $ 1 $ 130 2017 $ 130 $ 66 $ (77 ) $ (1 ) $ 118 Environmental liabilities 2015 $ 91 $ 7 $ (17 ) $ 12 $ 93 2016 $ 93 $ 6 $ (12 ) $ (2 ) $ 85 2017 $ 85 $ 5 $ (8 ) $ (4 ) $ 78 (1) Includes WCB, FELA, occupational, foreign car damage and property & lading damage claims.

Summary of Significant Accoun37

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Basis of Accounting, US GAAP	These Consolidated Financial Statements are expressed in Canadian dollars and have been prepared in accordance with GAAP.
Principles of consolidation	These Consolidated Financial Statements include the accounts of CP and all its subsidiaries. The Company’s investments in which it has significant influence are accounted for using the equity method. All intercompany accounts and transactions have been eliminated.
Use of estimates	The preparation of these Consolidated Financial Statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of revenues and expenses during the year, the reported amounts of assets and liabilities, and the disclosure of contingent assets and liabilities at the date of the financial statements. Management regularly reviews its estimates, including those related to environmental liabilities, pensions and other benefits, depreciable lives of properties, deferred income tax assets and liabilities, as well as legal and personal injury liabilities based upon currently available information. Actual results could differ from these estimates.
Revenue recognition	Railway freight revenues are recognized based on the percentage of completed service method. The allocation of revenue between reporting periods is based on the relative transit time in each reporting period with expenses recognized as incurred. Volume rebates to customers are accrued as a reduction of freight revenues based on estimated volume and contract terms as freight service is provided. Other revenues, including passenger revenue, revenue from leasing certain assets, switching fees, and revenue from logistics services, are recognized as service is performed or contractual obligations are met. Revenues are presented net of taxes collected from customers and remitted to government authorities.
Cash and cash equivalents	Cash and cash equivalents include highly liquid short-term investments that are readily convertible to cash with original maturities of 3 months
Restricted cash and cash equivalents	Cash and cash equivalents that are restricted as to withdrawal or usage, in accordance with specific agreements, are presented as restricted cash and cash equivalents on the balance sheets when applicable. In the Consolidated Statements of Cash Flow, these balances, if any, are included with cash and cash equivalents.
Foreign currency translation	Assets and liabilities denominated in foreign currencies, other than those held through foreign subsidiaries, are translated into Canadian dollars at the year-end exchange rate for monetary items and at the historical exchange rates for non-monetary items. Foreign currency revenues and expenses are translated at the exchange rates in effect on the dates of the related transactions. Foreign exchange ("FX") gains and losses, other than those arising from the translation of the Company’s net investment in foreign subsidiaries, are included in income. The accounts of the Company’s foreign subsidiaries are translated into Canadian dollars using the year-end exchange rate for assets and liabilities and the average exchange rates during the year for revenues, expenses, gains and losses. FX gains and losses arising from the translation of the foreign subsidiaries’ assets and liabilities are included in “Other comprehensive income (loss)”. A portion of U.S. dollar-denominated long-term debt has been designated as a hedge of the net investment in foreign subsidiaries. As a result, unrealized FX gains and losses on U.S. dollar-denominated long-term debt, designated as a hedge, are offset against FX gains and losses arising from the translation of foreign subsidiaries’ accounts in “Other comprehensive income (loss)”.
Pensions and other benefits	Pension costs are actuarially determined using the projected-benefit method pro-rated over the credited service periods of employees. This method incorporates management’s best estimates of expected plan investment performance, salary escalation and retirement ages of employees. The expected return on fund assets is calculated using market-related asset values developed from a five-year average of market values for the fund’s public equity securities and absolute return strategies (with each prior year’s market value adjusted to the current date for assumed investment income during the intervening period) plus the market value of the fund’s fixed income, real estate and infrastructure securities, subject to the market-related asset value not being greater than 120% of the market value nor being less than 80% of the market value. The discount rate used to determine the projected-benefit obligation is based on blended market interest rates on high-quality corporate debt instruments with matching cash flows. Unrecognized actuarial gains and losses in excess of 10% of the greater of the benefit obligation and the market-related value of plan assets are amortized over the expected average remaining service period of active employees expected to receive benefits under the plan (approximately 12 years). Prior service costs arising from collectively bargained amendments to pension plan benefit provisions are amortized over the term of the applicable union agreement. Prior service costs arising from all other sources are amortized over the expected average remaining service period of active employees who are expected to receive benefits under the plan at the date of amendment. Costs for post-retirement and post-employment benefits other than pensions, including post-retirement health care and life insurance and some workers’ compensation and long-term disability benefits in Canada, are actuarially determined on a basis similar to pension costs. The over or under funded status of defined benefit pension and other post-retirement benefit plans are measured as the difference between the fair value of the plan assets and the benefit obligation, and are recognized on the balance sheets. In addition, any unrecognized actuarial gains and losses and prior service costs and credits that arise during the period are recognized as a component of “Other comprehensive income (loss)”, net of tax.
Materials and supplies	Materials and supplies are carried at the lower of average cost or market value and consist primarily of fuel and parts used in the repair and maintenance of track structures, equipment, locomotives and freight cars.
Properties	Fixed asset additions and major renewals are recorded at cost, including direct costs, attributable indirect costs and carrying costs, less accumulated depreciation and any impairment. When there is a legal obligation associated with the retirement of property, a liability is initially recognized at its fair value and a corresponding asset retirement cost is added to the gross book value of the related asset and amortized to expense over the estimated term to retirement. The Company reviews the carrying amounts of its properties whenever changes in circumstances indicate that such carrying amounts may not be recoverable based on future undiscounted cash flows. When such properties are determined to be impaired, recorded asset values are revised to their fair value and an impairment loss is recognized. The Company recognizes expenditures as additions to properties or operating expenses based on whether the expenditures increase the output or service capacity, lower the associated operating costs or extend the useful life of the properties and whether the expenditures exceed minimum physical and financial thresholds. Much of the additions to properties, both new and replacement properties, are self-constructed. These are initially recorded at cost, including direct costs and attributable indirect costs, overheads and carrying costs. Direct costs include, among other things, labour costs, purchased services, equipment costs and material costs. Attributable indirect costs and overheads include incremental long-term variable costs resulting from the execution of capital projects. Indirect costs mainly include work trains, material distribution, highway vehicles and work equipment. Overheads primarily include a portion of the engineering department’s costs, which plans, designs and administers these capital projects. These costs are allocated to projects by applying a measure consistent with the nature of the cost, based on cost studies. For replacement properties, the project costs are allocated to dismantling and installation based on cost studies. Dismantling work is performed concurrently with the installation. Ballast programs including undercutting, shoulder ballasting and renewal programs that form part of the annual track program are capitalized as this work, and the related added ballast material, significantly improves drainage, which in turn extends the life of ties and other track materials. These costs are tracked separately from the underlying assets and depreciated over the period to the next estimated similar ballast program. Spot replacement of ballast is considered a repair which is expensed as incurred. The costs of large refurbishments are capitalized and locomotive overhauls are expensed as incurred, except where overhauls represent a betterment of the locomotive in which case costs are capitalized. The Company capitalizes development costs for major new computer systems. The Company follows group depreciation, which groups assets which are similar in nature and have similar economic lives. The property groups are depreciated on a straight-line basis reflecting their expected economic lives determined by depreciation studies. Depreciation studies are regular reviews of asset service lives, salvage values, accumulated depreciation and other related factors. Depreciation rates are established through these studies. Actual use and retirement of assets may vary from current estimates, and would be identified in the next study. These changes in expected economic lives would impact the amount of depreciation expense recognized in future periods. All track assets are depreciated using a straight-line method which recognizes the value of the asset consumed as a percentage of the whole life of the asset. When depreciable property is retired or otherwise disposed of in the normal course of business, the book value, less net salvage proceeds, is charged to accumulated depreciation and if different than the assumptions under the depreciation study could potentially result in adjusted depreciation expense over a period of years. However, when removal costs exceed the salvage value on assets and the Company has no legal obligation to remove the assets, the removal costs incurred are charged to income in the period in which the assets are removed and are not charged to accumulated depreciation. For certain asset classes, the historical cost of the asset is separately recorded in the Company’s property records. This amount is retired from the property records upon retirement of the asset. For assets for which the historical cost cannot be separately identified the amount of the gross book value to be retired is estimated using either an indexation methodology, whereby the current replacement cost of the asset is indexed to the estimated year of installation for the asset, or a first-in, first-out approach, or statistical analysis is used to determine the age of the retired asset. CP uses indices that closely correlate to the principal costs of the assets. There are a number of estimates inherent in the depreciation and retirement processes and as it is not possible to precisely estimate each of these variables until a group of property is completely retired, CP regularly monitors the estimated service lives of assets and the associated accumulated depreciation for each asset class to ensure depreciation rates are appropriate. If the recorded amounts of accumulated depreciation are greater or less than the amounts indicated by the depreciation studies then the excess or deficit is amortized as a component of depreciation expense over the remaining service lives of the applicable asset classes. For the sale or retirement of larger groups of depreciable assets that are unusual and were not considered in the Company’s depreciation studies, CP records a gain or loss for the difference between net proceeds and net book value of the assets sold or retired. The accumulated depreciation to be retired includes asset-specific accumulated depreciation, when known, and an appropriate portion of the accumulated depreciation recorded for the relevant asset class as a whole, calculated using a cost-based allocation. Revisions to the estimated useful lives and net salvage projections constitute a change in accounting estimate and are addressed prospectively by amending depreciation rates.
Assets held for sale	Assets to be disposed that meet the held for sale criteria are reported at the lower of their carrying amount and fair value, less costs to sell, and are no longer depreciated.
Goodwill and intangible assets	Goodwill represents the excess of the purchase price over the fair value of identifiable net assets upon acquisition of a business. Goodwill is assigned to the reporting units that are expected to benefit from the business acquisition which, after integration of operations with the railway network, may be different than the acquired business. The carrying value of goodwill, which is not amortized, is assessed for impairment annually in the fourth quarter of each year as at October 1st, or more frequently as economic events dictate. The Company has the option of performing an assessment of certain qualitative factors (“Step 0”) to determine if it is more likely than not that the fair value of a reporting unit is less than its carrying value or proceeding directly to a quantitative impairment test (“Step 1”). Qualitative factors include but are not limited to, economic, market and industry conditions, cost factors and overall financial performance of the reporting unit. If Step 0 indicates that the carrying value is less than the fair value, then performing the two-step impairment test is unnecessary. Under Step 1, the fair value of the reporting unit is compared to its carrying value, including goodwill. If the fair value of the reporting unit is less than its carrying value, goodwill is potentially impaired. The impairment charge that would be recognized is the excess of the carrying value of the goodwill over the fair value of the goodwill, determined in the same manner as in a business combination. Intangible assets with finite lives are amortized on a straight-line basis over the estimated useful lives of the respective assets. Favourable leases, customer relationships and interline contracts have amortization periods ranging from 15 to 20
Financial instruments	Financial instruments are contracts that give rise to a financial asset of one party and a financial liability or equity instrument of another party. Financial instruments are recognized initially at fair value, which is the amount of consideration that would be agreed upon in an arm’s-length transaction between willing parties.
Derivative financial instruments	Derivative financial and commodity instruments may be used from time to time by the Company to manage its exposure to risks relating to foreign currency exchange rates, stock-based compensation, interest rates and fuel prices. When CP utilizes derivative instruments in hedging relationships, CP identifies, designates and documents those hedging transactions and regularly tests the transactions to demonstrate effectiveness in order to continue hedge accounting. All derivative instruments are classified as held for trading and recorded at fair value. Any change in the fair value of derivatives not designated as hedges is recognized in the period in which the change occurs in the Consolidated Statements of Income in the line item to which the derivative instrument is related. On the Consolidated Balance Sheets they are classified in “Other assets”, “Other long-term liabilities”, “Other current assets” or “Accounts payable and accrued liabilities” as applicable. Gains and losses arising from derivative instruments may affect the following lines on the Consolidated Statements of Income: “Revenues”, “Compensation and benefits”, “Fuel”, “Other income and charges”, and “Net interest expense”. For fair value hedges, the periodic changes in values are recognized in income, on the same line as the changes in values of the hedged items are also recorded. For a cash flow hedge, the change in value of the effective portion is recognized in “Other comprehensive income (loss)”. Any ineffectiveness within an effective cash flow hedge is recognized in income as it arises in the same income account as the hedged item. Should a cash flow hedging relationship become ineffective, previously unrealized gains and losses remain within “Accumulated other comprehensive loss” until the hedged item is settled and, prospectively, future changes in value of the derivative are recognized in income. The change in value of the effective portion of a cash flow hedge remains in “Accumulated other comprehensive loss” until the related hedged item settles, at which time amounts recognized in “Accumulated other comprehensive loss” are reclassified to the same income or balance sheet account that records the hedged item.
Environmental remediation	Environmental remediation accruals, recorded on an undiscounted basis unless a reliably determinable estimate as to amount and timing of costs can be established, cover site-specific remediation programs. The accruals are recorded when the costs to remediate are probable and reasonably estimable. Certain future costs to monitor sites are discounted at an adjusted risk-free rate. Provisions for environmental remediation costs are recorded in “Other long-term liabilities”, except for the current portion, which is recorded in “Accounts payable and accrued liabilities”.
Income taxes	The Company follows the liability method of accounting for income taxes. Deferred income tax assets and liabilities are determined based on differences between the financial reporting and tax bases of assets and liabilities using enacted tax rates and laws that will be in effect when the differences are expected to reverse. The effect of a change in income tax rates on deferred income tax assets and liabilities is recognized in income in the period during which the change occurs. When appropriate, the Company records a valuation allowance against deferred tax assets to reflect that these tax assets may not be realized. In determining whether a valuation allowance is appropriate, CP considers whether it is more likely than not that all or some portion of CP’s deferred tax assets will not be realized, based on management’s judgment using available evidence about future events. At times, tax benefit claims may be challenged by a tax authority. Tax benefits are recognized only for tax positions that are more likely than not sustainable upon examination by tax authorities. The amount recognized is measured as the largest amount of benefit that is greater than 50% likely to be realized upon settlement. A liability for “unrecognized tax benefits” is recorded for any tax benefits claimed in CP’s tax returns that do not meet these recognition and measurement standards.
Earnings per share	Basic earnings per share are calculated using the weighted average number of common shares outstanding during the year. Diluted earnings per share are calculated using the treasury stock method for determining the dilutive effect of options.
Stock-based compensation	CP follows the fair value based approach to account for stock options. Compensation expense and an increase in “Additional paid-in capital” are recognized for stock options over their vesting period, or over the period from the grant date to the date employees become eligible to retire when this is shorter than the vesting period, based on their estimated fair values on the grant date, as determined using the Black-Scholes option-pricing model. Any consideration paid by employees on exercise of stock options is credited to “Share capital” when the option is exercised and the recorded fair value of the option is removed from “Additional paid-in capital" and credited to “Share capital”. Compensation expense is also recognized for deferred share units (“DSUs”), performance share units (“PSUs”) and restricted share units (“RSUs”) using the fair value method. Compensation expense is recognized over the vesting period, or for PSUs and DSUs only, over the period from the grant date to the date employees become eligible to retire when this is shorter than the vesting period. Forfeitures of DSUs, PSUs and RSUs are estimated at issuance and subsequently at the balance sheet date.

Accounting Changes Accounting

Accounting Changes Accounting Changes (Policies)	12 Months Ended
	Dec. 31, 2017
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Accounting Changes	Implemented in 2017 Compensation – Stock Compensation In March 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update (“ASU”) 2016-09, Improvements to Employee Share-based Payment Accounting, under FASB Accounting Standards Codification ("ASC") Topic 718. The amendments clarify the guidance relating to treatment of excess tax benefits and deficiencies, acceptable forfeiture rate policies, and treatment of cash paid by an employer when directly withholding shares for tax-withholding purposes and the requirement to treat such cash flows as a financing activity. As a result of this ASU, excess tax benefits are no longer recorded in additional paid- in capital and instead are applied against taxes payable or recognized in the Consolidated Statement of Income. This ASU was effective for CP beginning on January 1, 2017. The Company has determined that there were no significant changes to disclosure, financial statement presentation, and no material changes to accounting as a result of adoption. Simplifying the Measurement of Inventory In July 2015, the FASB issued ASU 2015-11, Simplifying the Measurement of Inventory under FASB ASC Topic 330. The amendments require that reporting entities measure inventory at the lower of cost and net realizable value. Net realizable value is the estimated selling price in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. The amendments apply to inventory that is measured using the first-in, first-out or average cost basis. This ASU was effective for CP beginning on January 1, 2017 and was applied prospectively. The Company determined there were no changes to disclosure, financial statement presentation, or valuation of inventory as a result of adoption. Future changes Revenue from Contracts with Customers In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers under FASB ASC Topic 606. The FASB has also issued several updates to ASU 2014-09. The guidance in Topic 606, as amended, will be effective for CP for interim and annual periods commencing January 1, 2018. CP will adopt the new standard by using the modified retrospective approach. CP has analyzed contracts and public tariffs for a significant proportion of the Company’s annual rail freight revenue, which represents greater than 95% of CP’s annual revenues, and has identified the distinct services provided to customers that represent performance obligations under contracts and public tariffs. CP has also assessed key contracts with customers that generate non-freight revenues. CP has concluded that recognizing rail freight revenues over time as performance obligations related to rail freight services are satisfied continues to be appropriate. Certain other services provided to customers are satisfied at a point in time and will continue to be recognized in this manner. CP has substantially completed its assessment of its revenues earned from contracts with customers and does not expect any significant adjustment to be required upon adoption of the standard. Additional disclosures will be provided in CP's first quarter 2018 financial statements. Compensation – Retirement Benefits In March 2017, the FASB issued ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Post-retirement Benefit Cost under FASB ASC Topic 715. The amendments clarify presentation requirements for net periodic pension cost and net periodic post-retirement benefit cost and require that an employer report the current service cost component in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net periodic benefit cost are required to be presented in the Consolidated Statement of Income separately from the current service cost component and outside a subtotal of income from operations. The amendments also restrict capitalization to the current service cost component when applicable. The amendments are effective for CP beginning on January 1, 2018. The amendments related to presentation are required to be applied retrospectively and the restrictions on capitalization of the current service cost component are applicable prospectively on the date of adoption. The impacts of the reclassification are detailed as follows: Year ended December 31 (in millions of Canadian dollars) 2017 2016 2015 Decrease in operating income $ 274 $ 167 $ 70 There will be no change to Net income or earnings per share as a result of adoption of this new standard. The new guidance restricting capitalization of pensions to the current service cost component of net periodic benefit cost will have no impact to operating income or amounts capitalized because the Company currently only capitalizes an appropriate portion of current service cost for self-constructed properties. CP is currently assessing the disclosure requirements of this ASU. Derivatives and Hedging In August 2017, the FASB issued Accounting Standards Update ASU 2017-12, Targeted Improvements to Accounting for Hedging Activities, under FASB ASC Topic 815. This is intended to improve the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities in its financial statements. These amendments also make targeted improvements to simplify the application of the hedge accounting guidance in current GAAP. The amendments require the entire change in the fair value of the hedging instrument to be recorded in other comprehensive income for effective cash flow hedges. Consequently, any ineffective portion of the change in fair value will, therefore, no longer be recorded to the Consolidated Statement of Income as it arises. The amendments are effective for CP beginning on January 1, 2019, although early adoption is permitted. Entities are required to apply the amendments in this update to hedging relationships existing on the date of adoption, reflected as a cumulative-effect adjustment as of the beginning of the fiscal year of adoption. Other amendments to presentation and disclosure are applied prospectively. The Company will early adopt this ASU effective January 1, 2018 and no significant cumulative-effect adjustment will be required. Leases In February 2016, the FASB issued ASU 2016-02, Leases under FASB ASC Topic 842. This new standard requires recognition of right-of-use assets and lease liabilities by lessees for those leases classified as finance and operating leases with a maximum term exceeding 12 months. For CP this new standard will be effective for interim and annual periods commencing January 1, 2019. Entities are required to use a modified retrospective approach to adopt this new standard. The Company has a detailed plan to implement the new standard and is assessing contractual arrangements, through a cross-functional team, that may qualify as leases under the new standard. CP is also working with a vendor to implement a lease management system which will assist in delivering the required accounting changes. CP's cross-functional team and the vendor finalized system requirements and developed work flows and testing scenarios that will permit system implementation and parallel testing in 2018 for CP's lease system solution. The impact of the new standard will be a material increase to right of use assets and lease liabilities on the Company's Consolidated Balance Sheets, primarily, as a result of operating leases currently not recognized on the balance sheet. The Company does not anticipate a material impact to Net income and is currently evaluating the impact adoption of this new standard will have on disclosure. Intangibles – Goodwill and Other

Summary of Significant Accoun39

Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Principal subsidiaries	The following list sets out CPRL’s principal railway operating subsidiaries, including the jurisdiction of incorporation. All of these subsidiaries are wholly owned, directly or indirectly, by CPRL as at December 31, 2017 . Principal subsidiary Incorporated under the laws of Canadian Pacific Railway Company Canada Soo Line Railroad Company (“Soo Line”) Minnesota Delaware and Hudson Railway Company, Inc. (“D&H”) Delaware Dakota, Minnesota & Eastern Railroad Corporation (“DM&E”) Delaware Mount Stephen Properties Inc. (“MSP”) Canada

Accounting Changes Accounting C

Accounting Changes Accounting Changes (Tables)	12 Months Ended
	Dec. 31, 2017
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Reclassification Impact of ASU 2017-07	The impacts of the reclassification are detailed as follows: Year ended December 31 (in millions of Canadian dollars) 2017 2016 2015 Decrease in operating income $ 274 $ 167 $ 70

Other Income and Charges (Table

Other Income and Charges (Tables)	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
Other Income and Charges	(in millions of Canadian dollars) 2017 2016 2015 Foreign exchange (gain) loss on long-term debt $ (186 ) $ (79 ) $ 297 Other foreign exchange gains (7 ) (5 ) (24 ) Early redemption premium on notes (Note 16) — — 47 Insurance recovery of legal settlement (10 ) — — Legal settlement — 25 — Charge on hedge roll and de-designation 13 — — Other 12 14 15 Total other income and charges $ (178 ) $ (45 ) $ 335

Net Interest Expense (Tables)

Net Interest Expense (Tables)	12 Months Ended
	Dec. 31, 2017
Interest Income (Expense), Net [Abstract]
Net Interest Expense	(in millions of Canadian dollars) 2017 2016 2015 Interest cost $ 491 $ 497 $ 409 Interest capitalized to Properties (16 ) (25 ) (14 ) Interest expense 475 472 395 Interest income (2 ) (1 ) (1 ) Net interest expense $ 473 $ 471 $ 394

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Summary of the Major Components of the Company's Income Tax Expense	The following is a summary of the major components of the Company’s income tax expense: (in millions of Canadian dollars) 2017 2016 2015 Current income tax expense $ 303 $ 233 $ 373 Deferred income tax expense Origination and reversal of temporary differences 371 336 105 Effect of tax rate (decrease) increase (541 ) — 23 Effect of hedge of net investment in foreign subsidiaries (42 ) (20 ) 100 Other 2 4 6 Total deferred income tax (recovery) expense (210 ) 320 234 Total income taxes $ 93 $ 553 $ 607 Income before income tax expense Canada $ 1,829 $ 1,513 $ 1,099 Foreign 669 639 860 Total income before income tax expense $ 2,498 $ 2,152 $ 1,959 Income tax expense Current Canada $ 257 $ 165 $ 173 Foreign 46 68 200 Total current income tax expense 303 233 373 Deferred Canada 256 207 163 Foreign (466 ) 113 71 Total deferred income tax (recovery) expense (210 ) 320 234 Total income taxes $ 93 $ 553 $ 607
Components of Deferred Income Tax Assets and Liabilities	The items comprising the deferred income tax assets and liabilities are as follows: (in millions of Canadian dollars) 2017 2016 Deferred income tax assets Amount related to tax losses carried forward $ 12 $ 18 Liabilities carrying value in excess of tax basis 88 149 Environmental remediation costs 16 30 Other 11 58 Total deferred income tax assets 127 255 Deferred income tax liabilities Properties carrying value in excess of tax basis 3,181 3,796 Pensions carrying value in excess of tax basis (1) 226 — Other 41 30 Total deferred income tax liabilities 3,448 3,826 Total net deferred income tax liabilities $ 3,321 $ 3,571 (1)
Expected Income Tax Expense Reconciled To Income Tax Expense	Expected income tax expense at statutory rates is reconciled to income tax expense as follows: (in millions of Canadian dollars, except percentage) 2017 2016 2015 Statutory federal and provincial income tax rate (Canada) 26.56 % 26.65 % 26.47 % Expected income tax expense at Canadian enacted statutory tax rates $ 663 $ 573 $ 519 Increase (decrease) in taxes resulting from: (Gains) losses not subject to tax (27 ) (23 ) 28 Canadian tax rate differentials 1 — 1 Foreign tax rate differentials (9 ) — 39 Effect of tax rate (decrease) increase (541 ) — 23 Other 6 3 (3 ) Income tax expense $ 93 $ 553 $ 607
Reconciliation of Uncertain Tax Positions In Relation To Unrecognized Tax Benefits for Canada and the United States	The following table provides a reconciliation of uncertain tax positions in relation to unrecognized tax benefits for Canada and the U.S. for the year ended December 31, 2017 : (in millions of Canadian dollars) 2017 2016 2015 Unrecognized tax benefits at January 1 $ 13 $ 15 $ 17 Increase in unrecognized: Tax benefits related to the current year — — 4 Dispositions: Gross uncertain tax benefits related to prior years — (2 ) (6 ) Unrecognized tax benefits at December 31 $ 13 $ 13 $ 15

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Number Of Shares Used In the Earnings Per Share Calculations	The number of shares used and the earnings per share calculations are reconciled as follows: (in millions of Canadian dollars, except per share data) 2017 2016 2015 Net income $ 2,405 $ 1,599 $ 1,352 Weighted average basic shares outstanding (millions) 145.9 149.6 159.7 Dilutive effect of weighted average number of stock options (millions) 0.4 0.9 1.3 Weighted average diluted shares outstanding (millions) 146.3 150.5 161.0 Earnings per share – basic $ 16.49 $ 10.69 $ 8.47 Earnings per share – diluted $ 16.44 $ 10.63 $ 8.40

Other Comprehensive Income (L45

Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss (Tables)	12 Months Ended
	Dec. 31, 2017
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Components of Other comprehensive (loss) income and related tax effects	The components of Other comprehensive income (loss) and the related tax effects are as follows: (in millions of Canadian dollars) Before Income tax (expense) recovery Net of tax For the year ended December 31, 2017 Unrealized foreign exchange (loss) gain on: Translation of the net investment in U.S. subsidiaries $ (295 ) $ — $ (295 ) Translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries (Note 17) 319 (42 ) 277 Change in derivatives designated as cash flow hedges: Realized loss on cash flow hedges recognized in income 25 (6 ) 19 Unrealized loss on cash flow hedges (6 ) 2 (4 ) Change in pension and other benefits actuarial gains and losses 84 (20 ) 64 Change in prior service pension and other benefit costs (4 ) 1 (3 ) Other comprehensive income $ 123 $ (65 ) $ 58 For the year ended December 31, 2016 Unrealized foreign exchange (loss) gain on: Translation of the net investment in U.S. subsidiaries $ (132 ) $ — $ (132 ) Translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries (Note 17) 150 (20 ) 130 Change in derivatives designated as cash flow hedges: Realized loss on cash flow hedges recognized in income 10 (2 ) 8 Unrealized loss on cash flow hedges (12 ) 2 (10 ) Change in pension and other benefits actuarial gains and losses (422 ) 113 (309 ) Change in prior service pension and other benefit costs (12 ) 3 (9 ) Other comprehensive loss $ (418 ) $ 96 $ (322 ) For the year ended December 31, 2015 Unrealized foreign exchange gain (loss) on: Translation of the net investment in U.S. subsidiaries $ 671 $ — $ 671 Translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries (Note 17) (757 ) 100 (657 ) Change in derivatives designated as cash flow hedges: Realized loss on cash flow hedges recognized in income 7 (2 ) 5 Unrealized loss on cash flow hedges (76 ) 21 (55 ) Change in pension and other benefits actuarial gains and losses 1,058 (281 ) 777 Change in prior service pension and other benefit costs 1 — 1 Other comprehensive income $ 904 $ (162 ) $ 742
Accumulated other comprehensive loss, Net of tax	The components of Accumulated other comprehensive loss, net of tax, are as follows: (in millions of Canadian dollars) 2017 2016 Unrealized foreign exchange gain on translation of the net investment in U.S. subsidiaries $ 443 $ 738 Unrealized foreign exchange loss on translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries (334 ) (611 ) Net deferred and unrealized losses on derivatives (88 ) (102 ) Amounts for defined benefit pension and other post-retirement plans not recognized in income (Note 20) (1,761 ) (1,822 ) Equity accounted investments (1 ) (2 ) Accumulated other comprehensive loss $ (1,741 ) $ (1,799 )
Changes in Accumulated other comprehensive loss by component	Changes in Accumulated other comprehensive loss by component are as follows: (in millions of Canadian dollars) Foreign currency (1) Derivatives and (1) Pension and post- (1) Total (1) Opening balance, 2017 $ 127 $ (104 ) $ (1,822 ) $ (1,799 ) Other comprehensive loss before reclassifications (17 ) (4 ) (50 ) (71 ) Amounts reclassified from accumulated other comprehensive loss (1 ) 19 111 129 Net current-period other comprehensive (loss) income (18 ) 15 61 58 Closing balance, 2017 $ 109 $ (89 ) $ (1,761 ) $ (1,741 ) Opening balance, 2016 $ 129 $ (102 ) $ (1,504 ) $ (1,477 ) Other comprehensive loss before reclassifications (2 ) (10 ) (456 ) (468 ) Amounts reclassified from accumulated other comprehensive loss — 8 138 146 Net current-period other comprehensive loss (2 ) (2 ) (318 ) (322 ) Closing balance, 2016 $ 127 $ (104 ) $ (1,822 ) $ (1,799 ) (1)
Amounts in Pension and post-retirement defined benefit plans reclassified from Accumulated other comprehensive loss	Amounts in Pension and post-retirement defined benefit plans reclassified from Accumulated other comprehensive loss are as follows: 2017 2016 Amortization of prior service costs (1) $ (4 ) $ (6 ) Recognition of net actuarial loss (1) 154 194 Total before income tax $ 150 $ 188 Income tax recovery (39 ) (50 ) Net of income tax $ 111 $ 138 (1)

Change in Non-Cash Working Ca46

Change in Non-Cash Working Capital Balances Related to Operations (Tables)	12 Months Ended
	Dec. 31, 2017
Supplemental Cash Flow Elements [Abstract]
Changes In Non-cash Working Capital Balances Related To Operations	(in millions of Canadian dollars) 2017 2016 2015 (Use) source of cash: Accounts receivable, net $ (91 ) $ 44 $ 80 Materials and supplies 9 14 15 Other current assets (26 ) (18 ) 55 Accounts payable and accrued liabilities (30 ) (95 ) 125 Change in non-cash working capital $ (138 ) $ (55 ) $ 275

Accounts Receivable, Net (Table

Accounts Receivable, Net (Tables)	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Accounts Receivable, Net	(in millions of Canadian dollars) 2017 2016 Freight $ 536 $ 461 Non-freight 176 162 712 623 Allowance for doubtful accounts (25 ) (32 ) Total accounts receivable, net $ 687 $ 591

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Investments	(in millions of Canadian dollars) 2017 2016 Rail investments accounted for on an equity basis $ 144 $ 136 Other investments 38 58 Total investments $ 182 $ 194

Properties (Tables)

Properties (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Net Properties	(in millions of Canadian dollars except percentages) 2017 2017 2016 Weighted average annual depreciation rate Cost Accumulated Net book Cost Accumulated Net book Track and roadway 2.8 % $ 17,285 $ 4,814 $ 12,471 $ 16,817 $ 4,573 $ 12,244 Buildings 3.0 % 719 196 523 662 178 484 Rolling stock 2.9 % 4,114 1,557 2,557 4,060 1,524 2,536 Information systems (1) 11.4 % 551 264 287 584 299 285 Other 5.1 % 1,760 582 1,178 1,691 551 1,140 Total $ 24,429 $ 7,413 $ 17,016 $ 23,814 $ 7,125 $ 16,689 (1) During 2017 , CP capitalized costs attributable to the design and development of internal-use software in the amount of $49 million ( 2016 – $46 million ; 2015 – $42 million ). Current year depreciation expense related to internal use software was $55 million ( 2016 – $63 million ; 2015 – $69 million
Capital Leases Included In Net Properties	(in millions of Canadian dollars) 2017 2016 Cost Accumulated Net book Cost Accumulated Net book Buildings $ 1 $ 1 $ — $ 1 $ 1 $ — Rolling stock 311 115 196 311 105 206 Total assets held under capital lease $ 312 $ 116 $ 196 $ 312 $ 106 $ 206

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill Intangible assets (in millions of Canadian dollars) Net Cost Accumulated Net Total goodwill and intangible assets Balance at December 31, 2015 $ 198 $ 22 $ (9 ) $ 13 $ 211 Amortization — — (1 ) (1 ) (1 ) Foreign exchange impact (7 ) — (1 ) (1 ) (8 ) Balance at December 31, 2016 $ 191 $ 22 $ (11 ) $ 11 $ 202 Amortization — — (1 ) (1 ) (1 ) Foreign exchange impact (13 ) — (1 ) (1 ) (14 ) Balance at December 31, 2017 $ 178 $ 22 $ (13 ) $ 9 $ 187

Other Assets (Tables)

Other Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets	(in millions of Canadian dollars) 2017 2016 Long-term materials $ 24 $ 22 Prepaid leases 5 6 Unamortized fees on credit facility 5 7 Contracted customer incentives 11 2 Long-term receivables 1 2 Other 23 18 Total other assets $ 69 $ 57

Accounts Payable and Accrued 52

Accounts Payable and Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Payables and Accruals [Abstract]
Accounts Payable and Accrued Liabilities	(in millions of Canadian dollars) 2017 2016 Trade payables $ 402 $ 352 Accrued charges 256 282 Income and other taxes payable 72 146 Accrued interest 128 137 Financial derivative liability (Note 17) 55 69 Payroll-related accruals 72 73 Accrued vacation 59 65 Dividends payable 82 73 Personal injury and other claims provision 28 26 Provision for environmental remediation (Note 18) 8 9 Stock-based compensation liabilities 32 40 Other 44 50 Total accounts payable and accrued liabilities $ 1,238 $ 1,322

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Components of Long-term Debt	(in millions of Canadian dollars except percentages) Maturity Currency 2017 2016 6.500% 10-year Notes (A) May 2018 U.S.$ $ 345 $ 369 6.250% 10-year Medium Term Notes (A) Jun 2018 CDN$ 375 375 7.250% 10-year Notes (A) May 2019 U.S.$ 439 469 9.450% 30-year Debentures (A) Aug 2021 U.S.$ 314 336 5.100% 10-year Medium Term Notes (A) Jan 2022 CDN$ 125 125 4.500% 10-year Notes (A) Jan 2022 U.S.$ 311 333 4.450% 12.5-year Notes (A) Mar 2023 U.S.$ 438 469 2.900% 10-year Notes (A) Feb 2025 U.S.$ 878 940 3.700% 10.5-year Notes (A) Feb 2026 U.S.$ 313 335 7.125% 30-year Debentures (A) Oct 2031 U.S.$ 439 470 5.750% 30-year Debentures (A) Mar 2033 U.S.$ 307 328 4.800% 20-year Notes (A) Sep 2035 U.S.$ 375 401 5.950% 30-year Notes (A) May 2037 U.S.$ 558 597 6.450% 30-year Notes (A) Nov 2039 CDN$ 400 400 5.750% 30-year Notes (A) Jan 2042 U.S.$ 308 330 4.800% 30-year Notes (A) Aug 2045 U.S.$ 687 736 6.125% 100-year Notes (A) Sep 2115 U.S.$ 1,129 1,208 5.41% Senior Secured Notes (B) Mar 2024 U.S.$ 111 126 6.91% Secured Equipment Notes (C) Oct 2024 CDN$ 120 133 7.49% Equipment Trust Certificates (D) Jan 2021 U.S.$ 52 56 Obligations under capital leases 6.57% – 6.99% (E) 2022 – 2026 U.S.$ 148 163 12.77% (E) Jan 2031 CDN$ 3 3 8,175 8,702 Perpetual 4% Consolidated Debenture Stock (F) U.S.$ 38 41 Perpetual 4% Consolidated Debenture Stock (F) G.B.£ 6 6 8,219 8,749 Less: Unamortized fees on long-term debt 60 65 8,159 8,684 Less: Long-term debt maturing within one year 746 25 $ 7,413 $ 8,659
Schedule of Capital Lease Obligations Included in Long-Term Debt	At December 31, 2017 , capital lease obligations included in long-term debt were as follows: (in millions of Canadian dollars) Year Capital leases Minimum lease payments in: 2018 $ 15 2019 15 2020 15 2021 15 2022 105 Thereafter 37 Total minimum lease payments 202 Less: Imputed interest (51 ) Present value of minimum lease payments 151 Less: Current portion (4 ) Long-term portion of capital lease obligations $ 147

Financial Instruments Financial

Financial Instruments Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Schedule of Fair Value and Carrying Value of Long-term Debt	The carrying values of financial instruments equal or approximate their fair values with the exception of long-term debt: (in millions of Canadian dollars) December 31, 2017 December 31, 2016 Long-term debt (including current maturities): Fair value $ 9,680 $ 9,981 Carrying value 8,159 8,684

Other Long-Term Liabilities (Ta

Other Long-Term Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Other Liabilities Disclosure [Abstract]
Other Long-Term Liabilities	(in millions of Canadian dollars) 2017 2016 Provision for environmental remediation, net of current portion (1) $ 70 $ 76 Stock-based compensation liabilities, net of current portion 67 72 Deferred revenue on rights-of-way license agreements, net of current portion (2) 26 29 Deferred retirement compensation 4 29 Deferred gains on sale leaseback transactions (2) 16 19 Other, net of current portion 48 59 Total other long-term liabilities $ 231 $ 284 (1) As at December 31, 2017 , the aggregate provision for environmental remediation, including the current portion was $78 million ( 2016 – $85 million ). (2) The deferred revenue on rights-of-way license agreements, and deferred gains on sale leaseback transactions are being amortized to income on a straight-line basis over the related lease terms.

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Analysis of Common Share Balances	Common Share balances as at December 31: (number of shares in millions) 2017 2016 2015 Share capital, January 1 146.3 153.0 166.1 CP Common Shares repurchased (1.9 ) (6.9 ) (13.7 ) Shares issued under stock option plan 0.5 0.2 0.6 Share capital, December 31 144.9 146.3 153.0
Activities Under Shares Repurchase Program	The following table provides the activities under the share repurchase programs: 2017 2016 2015 Number of Common Shares repurchased 1,888,100 6,910,000 13,549,977 Weighted-average price per share (1) $ 201.53 $ 175.08 $ 202.79 Amount of repurchase (in millions) (1) $ 381 $ 1,210 $ 2,748 (1) Includes brokerage fees.

Pensions and Other Benefits (Ta

Pensions and Other Benefits (Tables)	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Net Periodic Benefit Cost for DB Pension Plans and Other Benefits	The elements of net periodic benefit cost for DB pension plans and other benefits recognized in the year include the following components: Pensions Other benefits (in millions of Canadian dollars) 2017 2016 2015 2017 2016 2015 Current service cost (benefits earned by employees in the year) $ 103 $ 106 $ 126 $ 12 $ 11 $ 12 Other components of net periodic benefit (recovery) cost: Interest cost on benefit obligation 451 467 463 20 21 21 Expected return on fund assets (893 ) (846 ) (816 ) — — — Recognized net actuarial loss (gain) 153 190 265 (1 ) 7 2 Amortization of prior service costs (5 ) (7 ) (6 ) 1 1 1 Total other components of net periodic benefit (recovery) cost (294 ) (196 ) (94 ) 20 29 24 Net periodic benefit (recovery) cost $ (191 ) $ (90 ) $ 32 $ 32 $ 40 $ 36
Information About DB Pension Plans and Other Benefits	Information about the Company’s DB pension plans and other benefits, in aggregate, is as follows: Pensions Other benefits (in millions of Canadian dollars) 2017 2016 2017 2016 Change in projected benefit obligation: Benefit obligation at January 1 $ 11,399 $ 11,194 $ 510 $ 513 Current service cost 103 106 12 11 Interest cost 451 467 20 21 Employee contributions 44 40 1 1 Benefits paid (648 ) (645 ) (35 ) (31 ) Foreign currency changes (15 ) (7 ) (3 ) — Plan amendments and other 1 6 — — Actuarial loss (gain) 344 238 13 (5 ) Projected benefit obligation at December 31 $ 11,679 $ 11,399 $ 518 $ 510 Pensions Other benefits (in millions of Canadian dollars) 2017 2016 2017 2016 Change in fund assets: Fair value of fund assets at January 1 $ 12,196 $ 12,300 $ 5 $ 6 Actual return on fund assets 1,183 461 (1 ) (1 ) Employer contributions 46 48 34 30 Employee contributions 44 40 1 1 Benefits paid (648 ) (645 ) (35 ) (31 ) Foreign currency changes (13 ) (8 ) — — Fair value of fund assets at December 31 $ 12,808 $ 12,196 $ 4 $ 5 Funded status – plan surplus (deficit) $ 1,129 $ 797 $ (514 ) $ (505 )
Funding Status of Pension Plans	2017 2016 (in millions of Canadian dollars) Pension Pension Pension Pension Projected benefit obligation at December 31 $ (11,174 ) $ (505 ) $ (10,902 ) $ (497 ) Fair value of fund assets at December 31 12,581 227 11,972 224 Funded Status $ 1,407 $ (278 ) $ 1,070 $ (273 )
Amounts Recognized in the Company's Consolidated Balance Sheets	Amounts recognized in the Company’s Consolidated Balance Sheets are as follows: Pensions Other benefits (in millions of Canadian dollars) 2017 2016 2017 2016 Pension asset $ 1,407 $ 1,070 $ — $ — Accounts payable and accrued liabilities (10 ) (10 ) (33 ) (34 ) Pension and other benefit liabilities (268 ) (263 ) (481 ) (471 ) Total amount recognized $ 1,129 $ 797 $ (514 ) $ (505 )
Amounts Recognized in Accumulated Other Comprehensive Losses	Amounts recognized in accumulated other comprehensive loss are as follows: Pensions Other benefits (in millions of Canadian dollars) 2017 2016 2017 2016 Net actuarial loss: Other than deferred investment gains $ 2,555 $ 2,842 $ 81 $ 66 Deferred investment gains (178 ) (366 ) — — Prior service cost (2 ) (7 ) 2 3 Deferred income tax (676 ) (699 ) (21 ) (17 ) Total (Note 7) $ 1,699 $ 1,770 $ 62 $ 52
Weighted-average Actuarial Assumptions Used	Weighted-average actuarial assumptions used were approximately: (percentages) 2017 2016 2015 Benefit obligation at December 31: Discount rate 3.80 4.02 4.22 Projected future salary increases 2.75 2.75 3.00 Health care cost trend rate 7.00 (1) 7.00 (1) 7.00 (2) Benefit cost for year ended December 31: Discount rate 4.02 4.22 4.09 Expected rate of return on fund assets 7.75 7.75 7.75 Projected future salary increases 2.75 3.00 3.00 Health care cost trend rate 7.00 (1) 7.00 (2) 7.00 (2) (1) The health care cost trend rate is assumed to be 7.00% in 2017 and 2018, and then decreasing by 0.50% per year to an ultimate rate of 5.00% per year in 2022 and thereafter. (2) The health care cost trend rate was previously assumed to be 6.50% in 2017 ( 7.00% in 2016 and 2015 ), and then decreasing by 0.50% per year to an ultimate rate of 5.00% per year in 2020 and thereafter.
Pension Plan Asset Allocation and Current Weighted Average Policy Range	The Company’s pension plan asset allocation, the current weighted average asset allocation targets and the current weighted average policy range for each major asset class, were as follows: Current Current Percentage of plan assets Asset allocation (percentage) 2017 2016 Cash and cash equivalents 0.5 0 – 5 1.4 1.1 Fixed income 29.5 20 – 40 26.1 21.4 Public equity 46.0 35 – 55 53.3 53.8 Real estate and infrastructure 12.0 4 – 20 6.2 7.5 Absolute return 12.0 0 – 18 13.0 16.2 Total 100.0 100.0 100.0
Summary of Defined Benefit Pension Plan Assets at Fair Value	The following is a summary of the assets of the Company’s DB pension plans at fair values at December 31, 2017 and 2016 : (in millions of Canadian dollars) Quoted prices in Significant other Significant Investments measured at NAV (1) Total December 31, 2017 Cash and cash equivalents $ 165 $ 11 $ — $ — $ 176 Fixed income • Government bonds (2) — 2,087 — — 2,087 • Corporate bonds (2) — 1,215 — — 1,215 • Mortgages (3) — 45 — — 45 Public equities • Canada 1,467 62 — — 1,529 • U.S. and international 5,254 42 — — 5,296 Real estate (4) — — — 622 622 Derivative assets (5) — — — — — Absolute return (6) • Funds of hedge funds — — — 681 681 • Multi-strategy funds — — — 515 515 • Credit funds — — — 252 252 • Equity funds — — — 214 214 Infrastructure (7) — — — 176 176 $ 6,886 $ 3,462 $ — $ 2,460 $ 12,808 December 31, 2016 Cash and cash equivalents $ 121 $ 11 $ — $ — $ 132 Fixed income • Government bonds (2) — 1,357 — — 1,357 • Corporate bonds (2) — 1,186 — — 1,186 • Mortgages (3) — 71 — — 71 Public equities • Canada 1,480 57 — — 1,537 • U.S. and international 4,985 36 — — 5,021 Real estate (4) — — 437 188 625 Derivative assets (5) — 7 — — 7 Absolute return (6) • Funds of hedge funds — — — 668 668 • Multi-strategy funds — — — 502 502 • Credit funds — — — 505 505 • Equity funds — — — 300 300 Infrastructure (7) — — — 285 285 $ 6,586 $ 2,725 $ 437 $ 2,448 $ 12,196 (1) Investments measured at net asset value ("NAV"): Amounts are comprised of certain investments measured at fair value using NAV (or its equivalent) as a practical expedient. These investments have not been classified in the fair value hierarchy. (2) Government & Corporate Bonds: Fair values for bonds are based on market prices supplied by independent sources as of the last trading day. (3) Mortgages: The fair value of mortgages of $45 million ( 2016 – $71 million ) is based on current market yields of financial instruments of similar maturity, coupon and risk factors. (4) Real estate: Real estate fund values of $622 million (2016 – $188 million ) are based on the NAV of the funds that invest directly in real estate investments. The fair values of the investments have been estimated using the capital accounts representing the plan’s ownership interest in the funds. Of the total, $542 million (2016 – $134 million ) is subject to redemption frequencies ranging from monthly to annually and a redemption notice period of 90 days. The remaining $80 million (2016 – $54 million ) is not subject to redemption and is normally returned through distributions as a result of the liquidation of the underlying real estate investments. There are $53 million of unfunded commitments for real estate investments as at December 31, 2017 ( 2016 – $81 million ). The fair value of real estate investments of $ nil ( 2016 – $437 million ) is based on property appraisals which use a number of approaches that typically include a discounted cash flow analysis, a direct capitalization income method and/or a direct comparison approach. Appraisals of real estate investments are generally performed semi-annually by qualified external accredited appraisers. (5) Derivatives: The Company’s pension funds may utilize the following derivative instruments: equity futures to replicate equity index returns (Level 2); currency forwards to partially hedge foreign currency exposures (Level 2); bond forwards to reduce asset/liability interest rate risk exposures (Level 2); interest rate swaps to manage duration and interest rate risk (Level 2); credit default swaps to manage credit risk (Level 2); and options to manage interest rate risk and volatility (Level 2). There are currency forwards with a notional value of $ nil (2016 – $937 million ) and a fair value of $ nil (2016 – $7 million ) as at December 31, 2017. (6) Absolute return: The fair value of absolute return fund investments of $1,662 million ( 2016 – $1,975 million ) is based on the NAV reported by the fund administrators. The funds have different redemption policies and periods. - Funds of hedge funds invest in a portfolio of hedge funds that allocate capital across a broad array of funds and/or investment managers, with monthly redemptions upon 95 days' notice. - Multi-strategy funds include funds that invest in broadly diversified portfolios of equity, fixed income and derivative instruments with quarterly redemptions upon 60 days' notice. - Credit funds invest in an array of fixed income securities with quarterly redemptions upon 60 days' notice. - Equity funds invest primarily in U.S. and global equity securities. Redemptions range from quarterly upon 60 days' notice to triennially upon 45 days' notice. (7) Infrastructure: Infrastructure fund values of $176 million ( 2016 – $285 million
Summary of Defined Benefit Pension Plan Assets Measured at FV Using Unobservable Inputs	During 2016 and 2017 the portion of the assets of the Company’s DB pension plans measured at fair value using unobservable inputs (Level 3) changed as follows: (in millions of Canadian dollars) Real Estate As at January 1, 2016 $ 451 Disbursements (36 ) Net realized gains 24 Decrease in net unrealized gains (2 ) As at December 31, 2016 $ 437 Disbursements (43 ) Net realized gains 7 Decrease in net unrealized gains (7 ) Net transfers (out of) Level 3 (394 ) As at December 31, 2017 $ —
Company Contributions to Pension Plans	he Company contributed the following to its different pension plans: (in millions of Canadian dollars) 2017 2016 2015 Canadian registered and U.S. qualified DB pension plans $ 33 $ 36 $ 69 Canadian non-registered supplemental pension plan 13 12 12 DC plans 9 9 9 Total Company pension contribution $ 55 $ 57 $ 90
Estimated Future DB Pension and Other Post-retirement Benefit Payments	The estimated future defined benefit pension and other benefit payments to be paid by the plans for each of the next five years and the subsequent five-year period are as follows: (in millions of Canadian dollars) Pensions Other benefits 2018 $ 609 $ 33 2019 614 31 2020 620 31 2021 625 31 2022 631 30 2023 – 2027 3,220 146

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Option Plan	The following table summarizes the Company’s stock option plan as at December 31, 2017 : Options outstanding Nonvested options Number of Weighted Number of Weighted Outstanding, January 1, 2017 2,450,082 $ 121.95 850,167 $ 44.49 Granted 369,980 $ 193.13 369,980 $ 45.78 Exercised (536,291 ) $ 84.93 N/A N/A Vested N/A N/A (328,265 ) $ 42.97 Forfeited (803,796 ) $ 120.97 (208,955 ) $ 47.21 Expired (700 ) $ 62.56 N/A N/A Outstanding, December 31, 2017 1,479,275 $ 150.64 682,927 $ 45.46 Vested or expected to vest at December 31, 2017 (1) 1,419,564 $ 149.05 N/A N/A Exercisable, December 31, 2017 796,348 $ 119.32 N/A N/A (1) As at December 31, 2017 , the weighted average remaining term of vested or expected to vest options was 7.0 years with an aggregate intrinsic value of $114 million .
Stock Options Outstanding and Exercisable	The following table provides the number of stock options outstanding and exercisable as at December 31, 2017 by range of exercise price and their related intrinsic aggregate value, and for options outstanding, the weighted-average years to expiration. The table also provides the aggregate intrinsic value for in-the-money stock options, which represents the amount that would have been received by option holders had they exercised their options on December 31, 2017 at the Company’s closing stock price of $229.66 . Options outstanding Options exercisable Range of exercise prices Number of Weighted Weighted Aggregate Number of Weighted Aggregate $36.29 – $117.48 416,270 3.7 $ 84.50 $ 60 416,270 $ 84.50 $ 60 $117.49 – $165.95 359,997 6.8 $ 141.38 $ 32 200,362 $ 128.43 $ 20 $165.96 – $190.42 415,914 6.1 $ 182.48 $ 20 106,458 $ 169.28 $ 6 $190.43 – $222.88 287,094 6.7 $ 212.05 $ 5 73,258 $ 219.60 $ 1 Total (1) 1,479,275 5.7 $ 150.64 $ 117 796,348 $ 119.32 $ 87 (1) As at December 31, 2017 , the total number of in-the-money stock options outstanding was 1,479,275 with a weighted-average exercise price of $150.64 . The weighted-average years to expiration of exercisable stock options is 4.9 years
Weighted-Average Fair Value Assumptions	The weighted average fair value assumptions were approximately: 2017 2016 2015 Expected option life (years) (1) 5.48 5.25 5.25 Risk-free interest rate (2) 1.85 % 1.21 % 1.10 % Expected stock price volatility (3) 27 % 27 % 26 % Expected annual dividends per share (4) $ 2.0010 $ 1.4000 $ 1.4000 Estimated forfeiture rate (5) 2.8 % 2.0 % 1.2 % Weighted average grant date fair value of options granted during the year $ 45.78 $ 39.01 $ 55.28 (1) Represents the period of time that awards are expected to be outstanding. Historical data on exercise behaviour or, when available, specific expectations regarding future exercise behaviour were used to estimate the expected life of the option. (2) Based on the implied yield available on zero-coupon government issues with an equivalent remaining term at the time of the grant. (3) Based on the historical stock price volatility of the Company’s stock over a period commensurate with the expected term of the option. (4) Determined by the current annual dividend at the time of grant. The Company does not employ different dividend yields throughout the contractual term of the option. On May 10, 2017, the Company announced an increase in its quarterly dividend to $0.5625 per share, representing $2.2500 on an annual basis. (5)
Schedule of Options Exercised	The following table provides information related to all options exercised in the stock option plan during the years ended December 31 : (in millions of Canadian dollars) 2017 2016 2015 Total intrinsic value $ 36 $ 30 $ 72 Cash received by the Company upon exercise of options $ 45 $ 21 $ 43
Summary of Performance Share Units Plan	The following table summarizes information related to the Company’s PSUs as at December 31 : 2017 2016 Outstanding, January 1 373,593 348,276 Granted 134,991 147,157 Units, in lieu of dividends 3,571 4,010 Settled (133,728 ) (83,466 ) Forfeited (44,399 ) (42,384 ) Outstanding, December 31 334,028 373,593
Summary of Deferred Share Units Plan	The following table summarizes information related to the DSUs as at December 31 : 2017 2016 Outstanding, January 1 234,036 318,176 Granted 23,932 31,069 Units, in lieu of dividends 1,969 2,798 Settled (33,682 ) (87,996 ) Forfeited (69,708 ) (30,011 ) Outstanding, December 31 156,547 234,036
Summary of Total Share Based Liabilities Paid	The following table summarizes the total share based liabilities paid for each of the years ended December 31 : (in millions of Canadian dollars) 2017 2016 2015 Plan DSUs $ 6 $ 17 $ 3 PSUs 31 31 79 Other 2 — 8 Total $ 39 $ 48 $ 90

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Minimum Future Lease Payments Under Operating Leases	As at December 31, 2017 , the Company’s commitments under operating leases were estimated at $351 million in aggregate, with minimum annual payments in each of the next five years and thereafter as follows: (in millions of Canadian dollars) Operating 2018 $ 71 2019 57 2020 45 2021 38 2022 31 Thereafter 109 Total minimum lease payments $ 351

Segmented and Geographic Info60

Segmented and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Geographic Information	Geographic information (in millions of Canadian dollars) Canada United States Total 2017 Revenues $ 4,667 $ 1,887 $ 6,554 Long-term assets excluding financial instruments and pension assets $ 11,505 $ 5,947 $ 17,452 2016 Revenues $ 4,473 $ 1,759 $ 6,232 Long-term assets excluding financial instruments and pension assets $ 11,000 $ 6,121 $ 17,121 2015 Revenues $ 4,662 $ 2,050 $ 6,712 Long-term assets excluding financial instruments and pension assets $ 10,630 $ 6,068 $ 16,698

Selected Quarterly Data (Unau61

Selected Quarterly Data (Unaudited) Selected Quarterly Data (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Data	For the quarter ended 2017 2016 (in millions of Canadian dollars, except per share data) Dec. 31 Sep. 30 Jun. 30 Mar. 31 Dec. 31 Sep. 30 Jun. 30 Mar. 31 Total revenues $ 1,713 $ 1,595 $ 1,643 $ 1,603 $ 1,637 $ 1,554 $ 1,450 $ 1,591 Operating income 753 690 679 671 717 657 551 653 Net income 984 510 480 431 384 347 328 540 Basic earnings per share (1) $ 6.79 $ 3.50 $ 3.28 $ 2.94 $ 2.63 $ 2.35 $ 2.16 $ 3.53 Diluted earnings per share (1) 6.77 3.50 3.27 2.93 2.61 2.34 2.15 3.51 (1)

Condensed Consolidating Finan62

Condensed Consolidating Financial Information (Tables)	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Condensed Consolidating Statements of Income	CONDENSED CONSOLIDATING STATEMENTS OF INCOME YEAR ENDED DECEMBER 31, 2017 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Revenues Freight $ — $ 4,516 $ 1,859 $ — $ 6,375 Non-freight — 140 372 (333 ) 179 Total revenues — 4,656 2,231 (333 ) 6,554 Operating expenses Compensation and benefits — 601 427 7 1,035 Fuel — 522 155 — 677 Materials — 134 41 15 190 Equipment rents — 143 (1 ) — 142 Depreciation and amortization — 400 261 — 661 Purchased services and other — 826 585 (355 ) 1,056 Total operating expenses — 2,626 1,468 (333 ) 3,761 Operating income — 2,030 763 — 2,793 Less: Other income and charges (33 ) (149 ) 4 — (178 ) Net interest (income) expense (12 ) 517 (32 ) — 473 Income before income tax expense and equity in net earnings of subsidiaries 45 1,662 791 — 2,498 Less: Income tax expense (recovery) 7 475 (389 ) — 93 Add: Equity in net earnings of subsidiaries 2,367 1,180 — (3,547 ) — Net income $ 2,405 $ 2,367 $ 1,180 $ (3,547 ) $ 2,405 YEAR ENDED DECEMBER 31, 2016 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Revenues Freight $ — $ 4,332 $ 1,728 $ — $ 6,060 Non-freight — 134 386 (348 ) 172 Total revenues — 4,466 2,114 (348 ) 6,232 Operating expenses Compensation and benefits — 749 434 6 1,189 Fuel — 458 109 — 567 Materials — 130 32 18 180 Equipment rents — 204 (31 ) — 173 Depreciation and amortization — 422 218 — 640 Purchased services and other — 673 604 (372 ) 905 Total operating expenses — 2,636 1,366 (348 ) 3,654 Operating income — 1,830 748 — 2,578 Less: Other income and charges (40 ) (34 ) 29 — (45 ) Net interest expense (income) 1 493 (23 ) — 471 Income before income tax expense and equity in net earnings of subsidiaries 39 1,371 742 — 2,152 Less: Income tax expense 6 337 210 — 553 Add: Equity in net earnings of subsidiaries 1,566 532 — (2,098 ) — Net income $ 1,599 $ 1,566 $ 532 $ (2,098 ) $ 1,599 YEAR ENDED DECEMBER 31, 2015 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Revenues Freight $ — $ 4,532 $ 2,020 $ — $ 6,552 Non-freight — 128 363 (331 ) 160 Total revenues — 4,660 2,383 (331 ) 6,712 Operating expenses Compensation and benefits — 943 428 — 1,371 Fuel — 549 159 — 708 Materials — 148 36 — 184 Equipment rents — 181 (7 ) — 174 Depreciation and amortization — 411 184 — 595 Purchased services and other — 711 680 (331 ) 1,060 Gain on sale of Delaware & Hudson South — — (68 ) — (68 ) Total operating expenses — 2,943 1,412 (331 ) 4,024 Operating income — 1,717 971 — 2,688 Less: Other income and charges 84 322 (71 ) — 335 Net interest (income) expense (5 ) 447 (48 ) — 394 (Loss) income before income tax expense and equity in net earnings of subsidiaries (79 ) 948 1,090 — 1,959 Less: Income tax (recovery) expense (21 ) 303 325 — 607 Add: Equity in net earnings of subsidiaries $ 1,410 $ 765 $ — $ (2,175 ) $ — Net income $ 1,352 $ 1,410 $ 765 $ (2,175 ) $ 1,352
Condensed Consolidating Statements of Comprehensive Income	CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME YEAR ENDED DECEMBER 31, 2017 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Net income $ 2,405 $ 2,367 $ 1,180 $ (3,547 ) $ 2,405 Net gain (loss) in foreign currency translation adjustments, net of hedging activities — 318 (294 ) — 24 Change in derivatives designated as cash flow — 19 — — 19 Change in pension and post-retirement defined — 82 (2 ) — 80 Other comprehensive income (loss) before income taxes — 419 (296 ) — 123 Income tax (expense) recovery on above items — (66 ) 1 — (65 ) Equity accounted investments 58 (295 ) — 237 — Other comprehensive income (loss) 58 58 (295 ) 237 58 Comprehensive income $ 2,463 $ 2,425 $ 885 $ (3,310 ) $ 2,463 YEAR ENDED DECEMBER 31, 2016 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Net income $ 1,599 $ 1,566 $ 532 $ (2,098 ) $ 1,599 Net gain (loss) in foreign currency translation adjustments, net of hedging activities — 149 (131 ) — 18 Change in derivatives designated as cash flow — (2 ) — — (2 ) Change in pension and post-retirement defined — (443 ) 9 — (434 ) Other comprehensive loss before income taxes — (296 ) (122 ) — (418 ) Income tax recovery (expense) on above items — 99 (3 ) — 96 Equity accounted investments (322 ) (125 ) — 447 — Other comprehensive loss (322 ) (322 ) (125 ) 447 (322 ) Comprehensive income $ 1,277 $ 1,244 $ 407 $ (1,651 ) $ 1,277 YEAR ENDED DECEMBER 31, 2015 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Net income $ 1,352 $ 1,410 $ 765 $ (2,175 ) $ 1,352 Net (loss) gain in foreign currency translation adjustments, net of hedging activities — (757 ) 671 — (86 ) Change in derivatives designated as cash flow — (69 ) — — (69 ) Change in pension and post-retirement defined — 1,061 (2 ) — 1,059 Other comprehensive income before income taxes — 235 669 — 904 Income tax (expense) recovery on above items — (163 ) 1 — (162 ) Equity accounted investments 742 670 — (1,412 ) — Other comprehensive income 742 742 670 (1,412 ) 742 Comprehensive income $ 2,094 $ 2,152 $ 1,435 $ (3,587 ) $ 2,094
Condensed Consolidating Balance Sheets	CONDENSED CONSOLIDATING BALANCE SHEETS AS AT DECEMBER 31, 2017 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Assets Current assets Cash and cash equivalents $ — $ 241 $ 97 $ — $ 338 Accounts receivable, net — 508 179 — 687 Accounts receivable, intercompany 97 153 215 (465 ) — Short-term advances to affiliates 500 1,004 4,996 (6,500 ) — Materials and supplies — 120 32 — 152 Other current assets — 31 66 — 97 597 2,057 5,585 (6,965 ) 1,274 Long-term advances to affiliates 590 — 410 (1,000 ) — Investments — 27 155 — 182 Investments in subsidiaries 10,623 12,122 — (22,745 ) — Properties — 8,982 8,034 — 17,016 Goodwill and intangible assets — — 187 — 187 Pension asset — 1,407 — — 1,407 Other assets — 56 13 — 69 Deferred income taxes 3 — — (3 ) — Total assets $ 11,813 $ 24,651 $ 14,384 $ (30,713 ) $ 20,135 Liabilities and shareholders’ equity Current liabilities Accounts payable and accrued liabilities $ 82 $ 844 $ 312 $ — $ 1,238 Accounts payable, intercompany 3 309 153 (465 ) — Short-term advances from affiliates 5,291 1,185 24 (6,500 ) — Long-term debt maturing within one year — 746 — — 746 5,376 3,084 489 (6,965 ) 1,984 Pension and other benefit liabilities — 672 77 — 749 Long-term advances from affiliates — 1,000 — (1,000 ) — Other long-term liabilities — 108 123 — 231 Long-term debt — 7,362 51 — 7,413 Deferred income taxes — 1,802 1,522 (3 ) 3,321 Total liabilities 5,376 14,028 2,262 (7,968 ) 13,698 Shareholders’ equity Share capital 2,032 1,037 6,730 (7,767 ) 2,032 Additional paid-in capital 43 1,643 259 (1,902 ) 43 Accumulated other comprehensive (loss) income (1,741 ) (1,742 ) 417 1,325 (1,741 ) Retained earnings 6,103 9,685 4,716 (14,401 ) 6,103 6,437 10,623 12,122 (22,745 ) 6,437 Total liabilities and shareholders’ equity $ 11,813 $ 24,651 $ 14,384 $ (30,713 ) $ 20,135 AS AT DECEMBER 31, 2016 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Assets Current assets Cash and cash equivalents $ — $ 100 $ 64 $ — $ 164 Accounts receivable, net — 435 156 — 591 Accounts receivable, intercompany 90 113 206 (409 ) — Short-term advances to affiliates 500 692 4,035 (5,227 ) — Materials and supplies — 150 34 — 184 Other current assets — 38 32 — 70 590 1,528 4,527 (5,636 ) 1,009 Long-term advances to affiliates 1 — 91 (92 ) — Investments — 47 147 — 194 Investments in subsidiaries 8,513 10,249 — (18,762 ) — Properties — 8,756 7,933 — 16,689 Goodwill and intangible assets — — 202 — 202 Pension asset — 1,070 — — 1,070 Other assets 1 48 8 — 57 Deferred income taxes 11 — — (11 ) — Total assets $ 9,116 $ 21,698 $ 12,908 $ (24,501 ) $ 19,221 Liabilities and shareholders’ equity Current liabilities Accounts payable and accrued liabilities $ 73 $ 945 $ 304 $ — $ 1,322 Accounts payable, intercompany 14 292 103 (409 ) — Short-term advances from affiliates 4,403 816 8 (5,227 ) — Long-term debt maturing within one year — 25 — — 25 4,490 2,078 415 (5,636 ) 1,347 Pension and other benefit liabilities — 658 76 — 734 Long-term advances from affiliates — 92 — (92 ) — Other long-term liabilities — 152 132 — 284 Long-term debt — 8,605 54 — 8,659 Deferred income taxes — 1,600 1,982 (11 ) 3,571 Total liabilities 4,490 13,185 2,659 (5,739 ) 14,595 Shareholders’ equity Share capital 2,002 1,037 5,823 (6,860 ) 2,002 Additional paid-in capital 52 1,638 298 (1,936 ) 52 Accumulated other comprehensive (loss) income (1,799 ) (1,799 ) 712 1,087 (1,799 ) Retained earnings 4,371 7,637 3,416 (11,053 ) 4,371 4,626 8,513 10,249 (18,762 ) 4,626 Total liabilities and shareholders’ equity $ 9,116 $ 21,698 $ 12,908 $ (24,501 ) $ 19,221
Condensed Consolidating Statements of Cash Flows	CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS YEAR ENDED DECEMBER 31, 2017 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Cash provided by operating activities $ 338 $ 1,334 $ 989 $ (479 ) $ 2,182 Investing activities Additions to properties — (950 ) (390 ) — (1,340 ) Proceeds from sale of properties and other assets — 29 13 — 42 Advances to affiliates (590 ) (550 ) (1,528 ) 2,668 — Repayment of advances to affiliates — 242 243 (485 ) — Capital contributions to affiliates — (1,039 ) — 1,039 — Repurchase of share capital from affiliates — 156 — (156 ) — Other — 5 (2 ) — 3 Cash used in investing activities (590 ) (2,107 ) (1,664 ) 3,066 (1,295 ) Financing activities Dividends paid (310 ) (310 ) (169 ) 479 (310 ) Issuance of share capital — — 1,039 (1,039 ) — Return of share capital to affiliates — — (156 ) 156 — Issuance of CP Common Shares 45 — — — 45 Purchase of CP Common Shares (381 ) — — — (381 ) Repayment of long-term debt, excluding commercial paper — (32 ) — — (32 ) Advances from affiliates 1,383 1,285 — (2,668 ) — Repayment of advances from affiliates (485 ) — — 485 — Settlement of forward starting swaps — (22 ) — — (22 ) Cash provided by (used in) financing activities 252 921 714 (2,587 ) (700 ) Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents — (7 ) (6 ) — (13 ) Cash position Increase in cash and cash equivalents — 141 33 — 174 Cash and cash equivalents at beginning of year — 100 64 — 164 Cash and cash equivalents at end of year $ — $ 241 $ 97 $ — $ 338 YEAR ENDED DECEMBER 31, 2016 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Cash provided by operating activities $ 255 $ 1,424 $ 879 $ (469 ) $ 2,089 Investing activities Additions to properties — (728 ) (454 ) — (1,182 ) Proceeds from sale of properties and other assets — 102 14 — 116 Advances to affiliates — (664 ) (539 ) 1,203 — Repayment of advances to affiliates — 222 — (222 ) — Capital contributions to affiliates — (472 ) — 472 — Repurchase of share capital from affiliates — 8 — (8 ) — Other — — (3 ) — (3 ) Cash used in investing activities — (1,532 ) (982 ) 1,445 (1,069 ) Financing activities Dividends paid (255 ) (255 ) (214 ) 469 (255 ) Issuance of share capital — — 472 (472 ) — Return of share capital to affiliates — — (8 ) 8 — Issuance of CP Common Shares 21 — — — 21 Purchase of CP Common Shares (1,210 ) — — — (1,210 ) Repayment of long-term debt, excluding commercial paper — (24 ) (14 ) — (38 ) Net repayment of commercial paper — (8 ) — — (8 ) Advances from affiliates 1,189 — 14 (1,203 ) — Repayment of advances from affiliates — — (222 ) 222 — Other — (3 ) — — (3 ) Cash (used in) provided by financing activities (255 ) (290 ) 28 (976 ) (1,493 ) Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents — (4 ) (9 ) — (13 ) Cash position Decrease in cash and cash equivalents — (402 ) (84 ) — (486 ) Cash and cash equivalents at beginning of year — 502 148 — 650 Cash and cash equivalents at end of year $ — $ 100 $ 64 $ — $ 164 YEAR ENDED DECEMBER 31, 2015 (in millions of Canadian dollars) CPRL (Parent Guarantor) CPRC (Subsidiary Issuer) Non-Guarantor Subsidiaries Consolidating Adjustments and Eliminations CPRL Consolidated Cash provided by operating activities $ 2,283 $ 1,650 $ 1,074 $ (2,548 ) $ 2,459 Investing activities Additions to properties — (766 ) (756 ) — (1,522 ) Proceeds from the sale of Delaware & Hudson South — — 281 — 281 Proceeds from sale of properties and other assets — 103 11 — 114 Advances to affiliates (1,133 ) (311 ) (1,820 ) 3,264 — Repayment of advances to affiliates — 804 1,000 (1,804 ) — Capital contributions to affiliates — (1,655 ) — 1,655 — Repurchase of share capital from affiliates — 1,210 — (1,210 ) — Other — 6 (2 ) — 4 Cash used in investing activities (1,133 ) (609 ) (1,286 ) 1,905 (1,123 ) Financing activities Dividends paid (226 ) (2,272 ) (276 ) 2,548 (226 ) Issuance of share capital — — 1,655 (1,655 ) — Return of share capital to affiliates — — (1,210 ) 1,210 — Issuance of CP Common Shares 43 — — — 43 Purchase of CP Common Shares (2,787 ) — — — (2,787 ) Issuance of long-term debt, excluding commercial paper — 3,411 — — 3,411 Repayment of long-term debt, excluding commercial paper — (461 ) (44 ) — (505 ) Net repayment of commercial paper — (893 ) — — (893 ) Advances from affiliates 1,820 500 944 (3,264 ) — Repayment of advances from affiliates — (1,000 ) (804 ) 1,804 — Cash (used in) provided by financing activities (1,150 ) (715 ) 265 643 (957 ) Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents — 24 21 — 45 Cash position Increase in cash and cash equivalents — 350 74 — 424 Cash and cash equivalents at beginning of year — 152 74 — 226 Cash and cash equivalents at end of year $ — $ 502 $ 148 $ — $ 650

Summary of Significant Accoun63

Summary of Significant Accounting Policies - Narrative (Details)	12 Months Ended
	Dec. 31, 2017mi
Summary of Significant Accounting Policies [Line items]
Miles of railway	12,500
Short-term investments maturity, maximum	3 months
Expected return on fund assets, Market-related asset values used	five-year average of market values
Market-related asset value, Maximum percentage	120.00%
Market-related asset value, Minimum percentage	80.00%
Unrecognized actuarial gains and losses, Maximum percentage	10.00%
Expected average remaining service period of active employees expected to receive benefits	12 years
Probability threshold for recognizing income tax benefits to be realized upon settlement	50.00%
Favourable leases, customer relationships and interline contracts [Member] | Minimum [Member]
Summary of Significant Accounting Policies [Line items]
Amortization period of intangible assets with finite lives (years)	15 years
Favourable leases, customer relationships and interline contracts [Member] | Maximum [Member]
Summary of Significant Accounting Policies [Line items]
Amortization period of intangible assets with finite lives (years)	20 years

Accounting Changes - Narrative

Accounting Changes - Narrative (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounting Standards Update 2017-07 [Member]
Change in Accounting Estimate [Line Items]
New Accounting Pronouncement, Effect of Adoption, Quantification	CAD 274	CAD 167	CAD 70

Other Income and Charges (Detai

Other Income and Charges (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Income and Expenses [Abstract]
Foreign exchange (gain) loss on long-term debt	CAD (186)	CAD (79)	CAD 297
Other foreign exchange gains	(7)	(5)	(24)
Early redemption premium on notes	0	0	47
Insurance recovery of legal settlement	(10)	0	0
Legal settlement	0	25	0
Charge on hedge roll and de-designation	13	0	0
Other	12	14	15
Total other income and charges	CAD (178)	CAD (45)	CAD 335

Net Interest Expense (Details)

Net Interest Expense (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest Income (Expense), Net [Abstract]
Interest cost	CAD 491	CAD 497	CAD 409
Interest capitalized to Properties	(16)	(25)	(14)
Interest expense	475	472	395
Interest income	(2)	(1)	(1)
Net interest expense	CAD 473	CAD 471	CAD 394

Net Interest Expense - Narrativ

Net Interest Expense - Narrative (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest Income (Expense), Net [Abstract]
Interest on capital leases included in interest expense	CAD 11	CAD 11	CAD 11

Income Taxes - Summary of Major

Income Taxes - Summary of Major Components of Company's Income Tax Expense (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Current income tax expense	CAD 303	CAD 233	CAD 373
Origination and reversal of temporary differences	371	336	105
Effect of tax rate (decrease) increase	(541)	0	23
Translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries	(42)	(20)	100
Other	2	4	6
Total deferred income tax (recovery) expense	(210)	320	234
Income tax expense	93	553	607
Income before income tax expense
Canada	1,829	1,513	1,099
Foreign	669	639	860
Income before income tax expense	2,498	2,152	1,959
Current
Canada	257	165	173
Foreign	46	68	200
Total current income tax expense	303	233	373
Deferred
Canada	256	207	163
Foreign	(466)	113	71
Total deferred income tax (recovery) expense	(210)	320	234
Income tax expense	CAD 93	CAD 553	CAD 607

Income Taxes - Deferred Income

Income Taxes - Deferred Income Tax Assets and Liabilities (Details) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Deferred income tax assets
Amount related to tax losses carried forward	CAD 12	CAD 18
Liabilities carrying value in excess of tax basis	88	149
Environmental remediation costs	16	30
Other	11	58
Total deferred income tax assets	127	255
Deferred income tax liabilities
Properties carrying value in excess of tax basis	3,181	3,796
Pensions carrying value in excess of tax basis	226	0
Other	41	30
Total deferred income tax liabilities	3,448	3,826
Total net deferred income tax liabilities	CAD 3,321	CAD 3,571

Income Taxes - Expected Income

Income Taxes - Expected Income Tax Expense at Canadian Statutory Rates Reconciled to Income Tax Expense (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Statutory federal and provincial income tax rate (Canada)	26.56%	26.65%	26.47%
Expected income tax expense at Canadian enacted statutory tax rates	CAD 663	CAD 573	CAD 519
Increase (decrease) in taxes resulting from:
(Gains) losses not subject to tax	(27)	(23)	28
Canadian tax rate differentials	1	0	1
Foreign tax rate differentials	(9)	0	39
Effect of tax rate (decrease) increase	(541)	0	23
Other	6	3	(3)
Income tax expense	CAD 93	CAD 553	CAD 607

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - CAD	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Unrecognized tax benefits from capital losses	CAD 0	CAD 0
Effect of tax rate (decrease) increase	(541,000,000)	0	CAD 23,000,000
Income tax operating losses carried forward	11,000,000
Minimum tax credits	0
Investment tax credits	0
Total amount of accrued interest and penalties	1,000,000	1,000,000	4,000,000
The total amount of accrued interest and penalties associated with unrecognized tax benefit	CAD 11,000,000	CAD 10,000,000	CAD 9,000,000

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Uncertain Tax Positions Related to Unrecognized Tax Benefits (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Uncertain Tax Positions to Unrecognized Tax Benefits [Roll Forward]
Unrecognized tax benefits at January 1	CAD 13	CAD 15	CAD 17
Increase in unrecognized:
Tax benefits related to the current year	0	0	4
Dispositions:
Gross uncertain tax benefits related to prior years	0	(2)	(6)
Unrecognized tax benefits at December 31	CAD 13	CAD 13	CAD 15

Earnings Per Share - Narrative

Earnings Per Share - Narrative (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings Per Share [Abstract]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	1.4	2.2	2.5
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of options excluded from the computation of diluted earnings per share	0.3	0.4	0.2

Earnings Per Share - Number Of

Earnings Per Share - Number Of Shares Used In the Earnings Per Share Calculations (Details) - CAD CAD / shares in Units, shares in Millions, CAD in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings Per Share [Abstract]
Net income	CAD 984	CAD 510	CAD 480	CAD 431	CAD 384	CAD 347	CAD 328	CAD 540	CAD 2,405	CAD 1,599	CAD 1,352
Weighted average basic shares outstanding (in shares)									145.9	149.6	159.7
Dilutive effect of weighted average number of stock options (in shares)									0.4	0.9	1.3
Weighted average diluted shares outstanding (in shares)									146.3	150.5	161
Earnings per share - basic (in CAD per share)	CAD 6.79	CAD 3.50	CAD 3.28	CAD 2.94	CAD 2.63	CAD 2.35	CAD 2.16	CAD 3.53	CAD 16.49	CAD 10.69	CAD 8.47
Earnings per share - diluted (in CAD per share)	CAD 6.77	CAD 3.50	CAD 3.27	CAD 2.93	CAD 2.61	CAD 2.34	CAD 2.15	CAD 3.51	CAD 16.44	CAD 10.63	CAD 8.40

Other Comprehensive Income (L75

Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss - Components of Other Comprehensive Income (Loss) and Related Tax Effects (Detail) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Unrealized foreign exchange gain (loss) on: Before tax amount
Translation of the net investment in U.S. subsidiaries	CAD (295)	CAD (132)	CAD 671
Translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries	319	150	(757)
Change in derivatives designated as cash flow hedges: Before tax amount
Realized loss on cash flow hedges recognized in income	25	10	7
Unrealized loss on cash flow hedges	(6)	(12)	(76)
Change in pension and other benefits actuarial gains and losses	84	(422)	1,058
Change in prior service pension and other benefit costs	(4)	(12)	1
Comprehensive income (loss)	123	(418)	904
Unrealized foreign exchange gain (loss) on: Income tax recovery (expense)
Translation of the net investment in U.S. subsidiaries	0	0	0
Translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries	(42)	(20)	100
Change in derivatives designated as cash flow hedges: Income tax recovery (expense)
Realized loss on cash flow hedges recognized in income	(6)	(2)	(2)
Unrealized loss on cash flow hedges	2	2	21
Change in pension and other benefits actuarial gains and losses	(20)	113	(281)
Change in prior service pension and other benefit costs	1	3	0
Comprehensive income (loss)	(65)	96	(162)
Unrealized foreign exchange gain (loss) on: Net of tax amount
Translation of the net investment in U.S. subsidiaries	(295)	(132)	671
Translation of the U.S. dollar-denominated long-term debt designated as a hedge of the net investment in U.S. subsidiaries	277	130	(657)
Change in derivatives designated as cash flow hedges: Net of tax amount
Realized loss on cash flow hedges recognized in income	19	8	5
Unrealized loss on cash flow hedges	(4)	(10)	(55)
Change in pension and other benefits actuarial gains and losses	64	(309)	777
Change in prior service pension and other benefit costs	(3)	(9)	1
Other comprehensive income (loss)	CAD 58	CAD (322)	CAD 742

Other Comprehensive Income (L76

Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss, Net of Tax (Detail) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net deferred and unrealized losses on derivatives	CAD (88)	CAD (102)
Amounts for defined benefit pension and other post-retirement plans not recognized in income	(1,761)	(1,822)
Equity accounted investments	(1)	(2)
Accumulated other comprehensive loss	(1,741)	(1,799)	CAD (1,477)
Net investment in U.S. subsidiaries
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized foreign exchange gain (loss) on net investment	443	738
USD long-term debt designated as hedge of net investment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Unrealized foreign exchange gain (loss) on net investment	CAD (334)	CAD (611)

Other Comprehensive Income (L77

Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss by Component (Detail) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOC Income (Loss), Opening balance	CAD (1,799)	CAD (1,477)
Other comprehensive (loss) income before reclassifications	(71)	(468)
Amounts reclassified from accumulated other comprehensive loss	129	146
Net current-period other comprehensive income (loss)	58	(322)	CAD 742
AOC Income (Loss), Ending balance	(1,741)	(1,799)	(1,477)
Foreign currency net of hedging activities
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOC Income (Loss), Opening balance	127	129
Other comprehensive (loss) income before reclassifications	(17)	(2)
Amounts reclassified from accumulated other comprehensive loss	(1)	0
Net current-period other comprehensive income (loss)	(18)	(2)
AOC Income (Loss), Ending balance	109	127	129
Derivatives and other
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOC Income (Loss), Opening balance	(104)	(102)
Other comprehensive (loss) income before reclassifications	(4)	(10)
Amounts reclassified from accumulated other comprehensive loss	19	8
Net current-period other comprehensive income (loss)	15	(2)
AOC Income (Loss), Ending balance	(89)	(104)	(102)
Pension and post-retirement defined benefit plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOC Income (Loss), Opening balance	(1,822)	(1,504)
Other comprehensive (loss) income before reclassifications	(50)	(456)
Amounts reclassified from accumulated other comprehensive loss	111	138
Net current-period other comprehensive income (loss)	61	(318)
AOC Income (Loss), Ending balance	CAD (1,761)	CAD (1,822)	CAD (1,504)

Other Comprehensive Income (L78

Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Loss - Amounts in Pension and Post-Retirement Defined Benefit Plans Reclassification from AOCL (Detail) - CAD CAD in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total before income tax									CAD 2,498	CAD 2,152	CAD 1,959
Income tax recovery									(93)	(553)	(607)
Net of income tax	CAD 984	CAD 510	CAD 480	CAD 431	CAD 384	CAD 347	CAD 328	CAD 540	2,405	1,599	CAD 1,352
Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of prior service costs									(4)	(6)
Recognition of net actuarial loss									154	194
Total before income tax									150	188
Income tax recovery									(39)	(50)
Net of income tax									CAD 111	CAD 138

Change in Non-Cash Working Ca79

Change in Non-Cash Working Capital Balances Related to Operations - Change in Non-Cash Working Capital Balances Related to Operations (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Supplemental Cash Flow Elements [Abstract]
Accounts receivable, net	CAD (91)	CAD 44	CAD 80
Materials and supplies	9	14	15
Other current assets	(26)	(18)	55
Accounts payable and accrued liabilities	(30)	(95)	125
Change in non-cash working capital	CAD (138)	CAD (55)	CAD 275

Accounts Receivable, Net (Detai

Accounts Receivable, Net (Details) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, Gross	CAD 712	CAD 623
Allowance for doubtful accounts	(25)	(32)
Accounts receivable, net	687	591
Freight [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, Gross	536	461
Non-Freight [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, Gross	CAD 176	CAD 162

Accounts Receivable Net - Narra

Accounts Receivable Net - Narrative (Detail) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Receivables [Abstract]
Allowances recorded in Accounts receivable, net	CAD 25	CAD 32
Provisions of accounts receivable within Purchased services and other	CAD 3	CAD 7	CAD 7

Disposition of properties Dispo

Disposition of properties Disposition of properties - Proceeds and Gains on Sale (Details) CAD in Millions, $ in Millions	Sep. 18, 2015CAD	Sep. 18, 2015USD ($)	Dec. 31, 2016CAD	Mar. 31, 2016CAD	Sep. 30, 2015CAD	Dec. 31, 2017CAD	Dec. 31, 2016CAD	Dec. 31, 2015CAD
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of properties and other assets						CAD 42	CAD 116	CAD 114
Proceeds from the sale of property, plant and equipment						0	0	281
Gain on sale of property, pant and equipment						CAD 0	CAD 0	CAD 68
Obico rail yard [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of properties and other assets			CAD 38
Gain on sale of properties and other assets			37
Gain after tax on sale of properties and other assets			CAD 33
Arbutus Corridor [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from the sale of property, plant and equipment				CAD 55
Gain on sale of property, pant and equipment				50
Gain after tax on sale of property, plant and equipment				CAD 43
Delaware and Hudson Railway Company [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from the sale of property, plant and equipment	CAD 281	$ 214
Gain on sale of property, pant and equipment					CAD 68
Gain after tax on sale of property, plant and equipment					CAD 42

Disposition of properties Gain

Disposition of properties Gain on settlement of legal proceedings related to the purchase and sale of a building (Details) - Building Sale [Member] - CAD CAD in Millions	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loan amount		CAD 20
Purchase option carrying value		CAD 8
Proceeds from Sale of Buildings	CAD 59
Gain (Loss) on Sale of Building	31
Gain (Loss) on Sale of Building, after Tax	CAD 27

Investments (Details)

Investments (Details) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Rail investments accounted for on an equity basis	CAD 144	CAD 136
Other investments	38	58
Total investments	CAD 182	CAD 194

Properties - Net Properties (De

Properties - Net Properties (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Cost	CAD 24,429	CAD 23,814
Accumulated depreciation	7,413	7,125
Net book value	17,016	16,689
Depreciation expense	CAD 661	640	CAD 595
Track and railway [Member]
Property, Plant and Equipment [Line Items]
Average annual depreciation rate	2.80%
Cost	CAD 17,285	16,817
Accumulated depreciation	4,814	4,573
Net book value	CAD 12,471	12,244
Buildings [Member]
Property, Plant and Equipment [Line Items]
Average annual depreciation rate	3.00%
Cost	CAD 719	662
Accumulated depreciation	196	178
Net book value	CAD 523	484
Rolling stock [Member]
Property, Plant and Equipment [Line Items]
Average annual depreciation rate	2.90%
Cost	CAD 4,114	4,060
Accumulated depreciation	1,557	1,524
Net book value	CAD 2,557	2,536
Information systems [Member]
Property, Plant and Equipment [Line Items]
Average annual depreciation rate	11.40%
Cost	CAD 551	584
Accumulated depreciation	264	299
Net book value	CAD 287	285
Other [Member]
Property, Plant and Equipment [Line Items]
Average annual depreciation rate	5.10%
Cost	CAD 1,760	1,691
Accumulated depreciation	582	551
Net book value	1,178	1,140
Software Development [Member]
Property, Plant and Equipment [Line Items]
Capitalized costs attributable to design and development	49	46	42
Depreciation expense	CAD 55	CAD 63	CAD 69

Properties - Capital Leases Inc

Properties - Capital Leases Included in Properties (Details) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Capital Leased Assets [Line Items]
Cost	CAD 312	CAD 312
Accumulated depreciation	116	106
Net book value	196	206
Buildings [Member]
Capital Leased Assets [Line Items]
Cost	1	1
Accumulated depreciation	1	1
Net book value	0	0
Rolling stock [Member]
Capital Leased Assets [Line Items]
Cost	311	311
Accumulated depreciation	115	105
Net book value	CAD 196	CAD 206

Goodwill and Intangible Asset87

Goodwill and Intangible Assets (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Goodwill
Goodwill, Opening balance	CAD 191	CAD 198
Amortization	0	0
Foreign exchange impact	(13)	(7)
Goodwill, Ending balance	178	191
Intangible assets
Cost, Opening balance	22	22
Accumulated amortization, Opening balance	(11)	(9)
Net carrying amount, Opening balance	11	13
Amortization	(1)	(1)
Foreign exchange impact	(1)	(1)
Cost, Ending Balance	22	22
Accumulated amortization, Ending Balance	(13)	(11)
Net carrying amount, Ending balance	9	11
Total goodwill and intangible assets
Opening Balance	202	211
Amortization	(1)	(1)
Foreign exchange impact	(14)	(8)
Ending Balance	CAD 187	CAD 202

Other Assets (Details)

Other Assets (Details) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Long-term materials	CAD 24	CAD 22
Prepaid leases	5	6
Unamortized fees on credit facility	5	7
Contracted customer incentives	11	2
Long-term receivables	1	2
Other	23	18
Total other assets	CAD 69	CAD 57

Accounts Payable and Accrued 89

Accounts Payable and Accrued Liabilities (Details) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Trade payables	CAD 402	CAD 352
Accrued charges	256	282
Income and other taxes payable	72	146
Accrued interest	128	137
Derivative Liability, Current	55	69
Payroll-related accruals	72	73
Accrued vacation	59	65
Dividends payable	82	73
Personal injury and other claims provision	28	26
Provision for environmental remediation	8	9
Stock-based compensation liabilities	32	40
Other	44	50
Total accounts payable and accrued liabilities	CAD 1,238	CAD 1,322

Debt - Components of Long-term

Debt - Components of Long-term Debt (Detail) CAD in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017CAD	Dec. 31, 2017USD ($)	Dec. 31, 2016CAD	Dec. 31, 2016USD ($)
Debt Instrument [Line Items]
Long-term debt, including unamortized fees	CAD 8,219	$ 5,755	CAD 8,749	$ 5,763
Less: Unamortized fees on long-term debt	60		65
Long-term debt, including current debt	8,159		8,684
Less: Long-term debt maturing within one year	746		25
Long-term debt	CAD 7,413		CAD 8,659
6.500% 10-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	6.50%	6.50%	6.50%	6.50%
Debt Instrument, Maturity Date	May 15, 2018
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 345		CAD 369
6.250% 10-year Medium Term Notes [Member]
Debt Instrument [Line Items]
Interest rate	6.25%	6.25%	6.25%	6.25%
Debt Instrument, Maturity Date	Jun. 1, 2018
Currency in which payable	CDN$
Long-term debt, including unamortized fees	CAD 375		CAD 375
7.250% 10-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	7.25%	7.25%	7.25%	7.25%
Debt Instrument, Maturity Date	May 15, 2019
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 439		CAD 469
9.450% 30-year Debentures [Member]
Debt Instrument [Line Items]
Interest rate	9.45%	9.45%	9.45%	9.45%
Debt Instrument, Maturity Date	Aug. 1, 2021
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 314		CAD 336
5.100% 10-year Medium Term Notes [Member]
Debt Instrument [Line Items]
Interest rate	5.10%	5.10%	5.10%	5.10%
Debt Instrument, Maturity Date	Jan. 14, 2022
Currency in which payable	CDN$
Long-term debt, including unamortized fees	CAD 125		CAD 125
4.500% 10-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	4.50%	4.50%	4.50%	4.50%
Debt Instrument, Maturity Date	Jan. 15, 2022
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 311		CAD 333
4.450% 12.5-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	4.45%	4.45%	4.45%	4.45%
Debt Instrument, Maturity Date	Mar. 15, 2023
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 438		CAD 469
2.900% 10-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	2.90%	2.90%	2.90%	2.90%
Debt Instrument, Maturity Date	Feb. 1, 2025
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 878		CAD 940
3.700% 10.5-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	3.70%	3.70%	3.70%	3.70%
Debt Instrument, Maturity Date	Feb. 2, 2026
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 313		CAD 335
7.125% 30-year Debentures [Member]
Debt Instrument [Line Items]
Interest rate	7.125%	7.125%	7.125%	7.125%
Debt Instrument, Maturity Date	Oct. 15, 2031
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 439		CAD 470
5.750% 30-year Debentures [Member]
Debt Instrument [Line Items]
Interest rate	5.75%	5.75%	5.75%	5.75%
Debt Instrument, Maturity Date	Mar. 15, 2033
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 307		CAD 328
4.800% 20-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	4.80%	4.80%	4.80%	4.80%
Debt Instrument, Maturity Date	Sep. 15, 2035
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 375		CAD 401
5.950% 30-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	5.95%	5.95%	5.95%	5.95%
Debt Instrument, Maturity Date	May 15, 2037
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 558		CAD 597
6.450% 30-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	6.45%	6.45%	6.45%	6.45%
Debt Instrument, Maturity Date	Nov. 17, 2039
Currency in which payable	CDN$
Long-term debt, including unamortized fees	CAD 400		CAD 400
5.750% 30-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	5.75%	5.75%	5.75%	5.75%
Debt Instrument, Maturity Date	Jan. 15, 2042
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 308		CAD 330
4.800% 30-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	4.80%	4.80%	4.80%	4.80%
Debt Instrument, Maturity Date	Aug. 1, 2045
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 687		CAD 736
6.125% 100-year Notes [Member]
Debt Instrument [Line Items]
Interest rate	6.125%	6.125%	6.125%	6.125%
Debt Instrument, Maturity Date	Sep. 15, 2115
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 1,129		CAD 1,208
5.41% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Interest rate	5.41%	5.41%	5.41%	5.41%
Debt Instrument, Maturity Date	Mar. 3, 2024
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 111		CAD 126
6.91% Secured Equipment Notes [Member]
Debt Instrument [Line Items]
Interest rate	6.91%	6.91%	6.91%	6.91%
Debt Instrument, Maturity Date	Oct. 1, 2024
Currency in which payable	CDN$
Long-term debt, including unamortized fees	CAD 120		CAD 133
7.49% Equipment Trust Certificates [Member]
Debt Instrument [Line Items]
Interest rate	7.49%	7.49%	7.49%	7.49%
Debt Instrument, Maturity Date	Jan. 15, 2021
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 52		CAD 56
Obligations Under Capital Leases (6.57% - 6.99%) [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date Range, Start	Mar. 12, 2022
Debt Instrument, Maturity Date Range, End	Dec. 30, 2026
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 148		CAD 163
Obligations Under Capital Leases (6.57% - 6.99%) [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate	6.57%	6.57%	6.57%	6.57%
Obligations Under Capital Leases (6.57% - 6.99%) [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate	6.99%	6.99%	6.99%	6.99%
Obligations Under Capital Leases (12.77%) [Member]
Debt Instrument [Line Items]
Interest rate	12.77%	12.77%	12.77%	12.77%
Debt Instrument, Maturity Date	Jan. 1, 2031
Currency in which payable	CDN$
Long-term debt, including unamortized fees	CAD 3		CAD 3
Total Long-term Debt Before Perpetual Consolidated Debenture Stock [Member]
Debt Instrument [Line Items]
Long-term debt, including unamortized fees	CAD 8,175		CAD 8,702
Perpetual 4% Consolidated Debenture Stock (USD) [Member]
Debt Instrument [Line Items]
Interest rate	4.00%	4.00%	4.00%	4.00%
Currency in which payable	U.S.$
Long-term debt, including unamortized fees	CAD 38		CAD 41
Perpetual 4% Consolidated Debenture Stock (GBP) [Member]
Debt Instrument [Line Items]
Interest rate	4.00%	4.00%	4.00%	4.00%
Currency in which payable	G.B.£
Long-term debt, including unamortized fees	CAD 6		CAD 6

Debt - Narrative (Detail)

Debt - Narrative (Detail) CAD in Millions, $ in Millions	Dec. 31, 2017CAD	Dec. 31, 2017USD ($)	Dec. 31, 2016CAD	Dec. 31, 2016USD ($)
Debt Disclosure [Abstract]
Long-term debt and capital lease obligation current and non-current	CAD 8,219	$ 5,755	CAD 8,749	$ 5,763
Annual maturities and principal repayments in 2018	742
Annual maturities and principal repayments in 2019	462
Annual maturities and principal repayments in 2020	63
Annual maturities and principal repayments in 2021	353
Annual maturities and principal repayments in 2022	CAD 466

Debt - Components of Long-ter92

Debt - Components of Long-term Debt - B (Narrative) (Detail) - 5.41% Senior Secured Notes [Member] CAD in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2017CAD	Dec. 31, 2016
Debt Instrument [Line Items]
Interest rate		5.41%	5.41%
Value of locomotive units used as collateral | CAD		CAD 118
Final repayment of principal amount | $	$ 44

Debt - Components of Long-ter93

Debt - Components of Long-term Debt - C (Narrative) (Detail) - 6.91% Secured Equipment Notes [Member] - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Interest rate	6.91%	6.91%
Value of locomotive units used as collateral	CAD 107
Final repayment of principal amount	CAD 11

Debt - Components of Long-ter94

Debt - Components of Long-term Debt - D (Narrative) (Detail) - 7.49% Equipment Trust Certificates [Member] CAD in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2017CAD	Dec. 31, 2016
Debt Instrument [Line Items]
Interest rate		7.49%	7.49%
Value of locomotive units used as collateral | CAD		CAD 104
Final repayment of principal amount | $	$ 11

Debt - Components of Long-ter95

Debt - Components of Long-term Debt - E (Detail) - CAD	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Disclosure [Abstract]
Capital Leases, Future Minimum Payments Due in 2018	CAD 15,000,000
Capital Leases, Future Minimum Payments Due in 2019	15,000,000
Capital Leases, Future Minimum Payments Due in 2020	15,000,000
Capital Leases, Future Minimum Payments Due in 2021	15,000,000
Capital Leases, Future Minimum Payments Due in 2022	105,000,000
Capital Leases, Future Minimum Payments Due Thereafter	37,000,000
Total minimum lease payments	202,000,000
Less: Imputed interest	(51,000,000)
Present value of minimum lease payments	151,000,000
Less: Current portion	(4,000,000)
Long-term portion of capital lease obligations	147,000,000
Additions to property, plant and equipment under capital lease obligations	0	CAD 0	CAD 0
Carrying value of assets collateralizing capital lease obligations	CAD 196,000,000	CAD 206,000,000

Debt - Credit Facility (Narrati

Debt - Credit Facility (Narrative) (Detail) $ in Billions	Jun. 23, 2017	Dec. 31, 2017CAD	Dec. 31, 2017USD ($)	Dec. 31, 2016CAD	Dec. 31, 2016USD ($)
Debt Instrument [Line Items]
Posted collateral on letter of credit facility | CAD		CAD 150,000,000		CAD 0
Commercial Paper [Member]
Debt Instrument [Line Items]
Credit total available amount			$ 1
Commercial paper borrowings | CAD		0		0
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit total available amount			2
Remaining Borrowing Capacity			2		$ 2
Five-Year Portion [Member]
Debt Instrument [Line Items]
Credit total available amount			1
Debt Instrument, Maturity Date	Jun. 28, 2022
One-Year Plus One-Year Term-Out Portion [Member]
Debt Instrument [Line Items]
Credit total available amount			$ 1
Debt Instrument, Maturity Date	Jun. 27, 2019
Letters of Credit [Member]
Debt Instrument [Line Items]
Letters of Credit, Drawn | CAD		319,000,000		320,000,000
Maximum capacity under credit facility | CAD		CAD 600,000,000		CAD 600,000,000

Financial Instruments (Detail)

Financial Instruments (Detail) $ in Millions	3 Months Ended			12 Months Ended
	Jun. 30, 2017CAD	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Dec. 31, 2017CAD	Dec. 31, 2016CAD	Dec. 31, 2015CAD	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Schedule of Investments [Line Items]
Fair value of long-term debt				CAD 9,680,000,000	CAD 9,981,000,000
Deposits in the form of short-term Investments				0	0
Net unamortized gain related to FX forward contracts				0	1,000,000
Payment for settlement of forward starting swaps				22,000,000	0	CAD 0
Charge on hedge roll and de-designation				(13,000,000)	0	0
Forward Starting Swaps [Member]
Schedule of Investments [Line Items]
Gain (loss) on effective portion of hedge				(7,000,000)	(12,000,000)
Floating-to-fixed interest rate swaps, Notional amount | $			$ 700				$ 500	$ 700
Derivative, Notional Amount De-designated | $		$ 700	$ 700
Derivative, Notional Amount Settled | $		200
Payment for settlement of forward starting swaps	CAD 22,000,000	$ 16
Charge on hedge roll and de-designation	CAD (13,000,000)
Gain (Loss) on Derivative, Net				(8,000,000)	(9,000,000)
Forward Starting Swaps [Member] | Interest Expense [Member]
Schedule of Investments [Line Items]
Ineffective portion gain (loss)				(1,000,000)	3,000,000
Derivative losses amortized to net interest expense				11,000,000	11,000,000
Derivative gains (losses) expected to be amortized to net interest expense				(12,000,000)
Forward Starting Swaps [Member] | Accounts Payable and Accrued Liabilities [Member]
Schedule of Investments [Line Items]
Fair value loss				55,000,000	69,000,000
Treasury Rate Locks [Member]
Schedule of Investments [Line Items]
Unamortized losses, Treasury rate locks				20,000,000	21,000,000
Treasury Rate Locks [Member] | Interest Expense [Member]
Schedule of Investments [Line Items]
Derivative losses amortized to net interest expense				1,000,000	0	0
Derivative gains (losses) expected to be amortized to net interest expense				(1,000,000)
Accumulated Translation Adjustment [Member]
Schedule of Investments [Line Items]
Amount of net gain reclassified from AOCI				1,000,000	1,000,000
Net Investment Hedge [Member]
Schedule of Investments [Line Items]
Gain (loss) on effective portion of hedge				319,000,000	150,000,000	(757,000,000)
Amount of ineffectiveness on net investment hedge				0	0	CAD 0
Carrying Value Measurement [Member]
Schedule of Investments [Line Items]
Carrying value of long-term debt				CAD 8,159,000,000	CAD 8,684,000,000

Other Long-Term Liabilities (De

Other Long-Term Liabilities (Details) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Other Liabilities Disclosure [Abstract]
Provision for environmental remediation, net of current portion	CAD 70	CAD 76
Stock-based compensation liabilities, net of current portion	67	72
Deferred revenue on rights-of-way license agreements, net of current portion	26	29
Deferred retirement compensation	4	29
Deferred gains on sale leaseback transactions	16	19
Other, net of current portion	48	59
Total other long-term liabilities	231	284
Aggregate provision for environmental remediation, including current portion	CAD 78	CAD 85

Other Long-Term Liabilities - N

Other Long-Term Liabilities - Narrative (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Liabilities Disclosure [Abstract]
Expected time period for payment of Provision for environmental remediation	10 years
Environmental remediation costs charged to income	CAD 5	CAD 6	CAD 7

Shareholders Equity - Narrative

Shareholders Equity - Narrative (Details) - CAD	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	May 10, 2017	Apr. 20, 2016	Aug. 31, 2015	Mar. 16, 2015	Sep. 29, 2014	Mar. 11, 2014
Preferred shares issued (in shares)		0
Change in the share capital balances related to the cancellation of the liability on exercise of stock options		CAD 0	CAD 1,000,000	CAD 2,000,000
Common Shares repurchased (in shares)		1,900,000	6,900,000	13,700,000
CP Common Shares repurchased		CAD 381,000,000	CAD 1,210,000,000	CAD 2,748,000,000
Normal Course Issuer Bid (NCIB) [Member]
Common shares authorized to be repurchased											5,300,000
Share repurchase expiration date				Mar. 16, 2015
Common Shares repurchased (in shares)	2,200,000				10,500,000
CP Common Shares repurchased	CAD 490,000,000
Normal Course Issuer Bid (NCIB) [Member] | Minimum [Member]
Common shares authorized to be repurchased										5,300,000
Normal Course Issuer Bid (NCIB) [Member] | Maximum [Member]
Common shares authorized to be repurchased										12,700,000
Amended Normal Course Issuer Bid (NCIB) [Member]
Common shares authorized to be repurchased									9,100,000
Share repurchase expiration date			Mar. 17, 2016
Common Shares repurchased (in shares)				11,300,000
CP Common Shares repurchased				CAD 2,258,000,000
Amended Normal Course Issuer Bid (NCIB) [Member] | Minimum [Member]
Common shares authorized to be repurchased								9,100,000
Amended Normal Course Issuer Bid (NCIB) [Member] | Maximum [Member]
Common shares authorized to be repurchased								11,900,000
2016 Normal Course Issuer Bid (NCIB) [Member] [Domain]
Common shares authorized to be repurchased							6,900,000
Share repurchase expiration date			May 1, 2017
Common Shares repurchased (in shares)			6,910,000
CP Common Shares repurchased			CAD 1,210,000,000
Current Normal Course Issuer Bid (NCIB) [Member]
Common shares authorized to be repurchased						4,380,000
Share repurchase expiration date		May 14, 2018
Common Shares repurchased (in shares)		1,888,100
CP Common Shares repurchased		CAD 381,000,000
Additional Paid-in Capital [Member]
Adjustments to Additional Paid in Capital, Share-based Compensation and Exercise of Stock Options		12,000,000	5,000,000	10,000,000
CP Common Shares repurchased		CAD 0	CAD 0	CAD 0

Shareholders' Equity - Analysis

Shareholders' Equity - Analysis of Common Share Balances (Detail) - shares shares in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share capital, January 1	146.3	153	166.1
Common Shares repurchased (in shares)	(1.9)	(6.9)	(13.7)
Shares issued under stock option plan	0.5	0.2	0.6
Share capital, December 31	144.9	146.3	153

Shareholders' Equity - Activiti

Shareholders' Equity - Activities Under Shares Repurchase Program (Detail) - CAD CAD / shares in Units, CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Number of Common Shares repurchased (in shares)	1,900,000	6,900,000	13,700,000
CP Common Shares repurchased	CAD 381	CAD 1,210	CAD 2,748
Current Normal Course Issuer Bid (NCIB) [Member]
Number of Common Shares repurchased (in shares)	1,888,100
Treasury Stock Acquired, Average Cost Per Share	CAD 201.53
CP Common Shares repurchased	CAD 381
2016 Normal Course Issuer Bid (NCIB) [Member] [Domain]
Number of Common Shares repurchased (in shares)		6,910,000
Treasury Stock Acquired, Average Cost Per Share		CAD 175.08
CP Common Shares repurchased		CAD 1,210
Amended and Normal Course Issuer Bid (NCIB) [Member] [Member]
Number of Common Shares repurchased (in shares)			13,549,977
Treasury Stock Acquired, Average Cost Per Share			CAD 202.79
CP Common Shares repurchased			CAD 2,748

Pensions and Other Benefits - A

Pensions and Other Benefits - Additional Information (Detail) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Period of average market values for calculating net periodic benefit cost	5 years
Target long term rate of return, net of all fees and expenses	7.75%	7.75%	7.75%
Maximum value of underlying assets represented by financial derivatives, excluding currency forwards	30.00%
Company's common shares in fund assets, Shares	107,330	109,630
Payments to employees, their beneficiaries or estates or to third-party benefit administrators	CAD 34	CAD 30	CAD 33
Net cost of defined contribution plan	9	9	9
Multi-employer plan contributions	5	4	CAD 4
Equity Securities [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Company's securities in fund assets	25	21
Debt Securities [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Company's securities in fund assets	CAD 1	3
US Dollar [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plans exposure to foreign currency risk percentage	40.00%
European Currencies [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plans exposure to foreign currency risk percentage	11.00%
Other Currency [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plans exposure to foreign currency risk percentage	7.00%
Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Defined benefit pension plans' accumulated benefit obligation	CAD 11,273	CAD 11,143
Unamortized actuarial loss expected to be recognized in next fiscal year	114
Unamortized prior service cost expected to be recognized in next fiscal year	3
Other Postretirement Benefit Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Unamortized actuarial loss expected to be recognized in next fiscal year	3
Unamortized prior service cost expected to be recognized in next fiscal year	CAD 0
Canadian pension plans
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Canadian pension plan as a percentage of combined plan assets	99.00%
Canadian pension plan as a percentage of combined plan obligations	98.00%
Canadian other benefits plans as a percentage of combined other plan obligations	96.00%

Pensions and Other Benefits - N

Pensions and Other Benefits - Net Periodic Benefit Cost for DB Pension Plans and Other Benefits (Detail) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Current service cost (benefits earned by employees in the year)	CAD 103	CAD 106	CAD 126
Interest cost on benefit obligation	451	467	463
Expected return on fund assets	(893)	(846)	(816)
Recognized net actuarial loss (gain)	153	190	265
Amortization of prior service costs	(5)	(7)	(6)
Total other components of net periodic benefit (recovery) cost	(294)	(196)	(94)
Net periodic benefit (recovery) cost	(191)	(90)	32
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Current service cost (benefits earned by employees in the year)	12	11	12
Interest cost on benefit obligation	20	21	21
Expected return on fund assets	0	0	0
Recognized net actuarial loss (gain)	(1)	7	2
Amortization of prior service costs	1	1	1
Total other components of net periodic benefit (recovery) cost	20	29	24
Net periodic benefit (recovery) cost	CAD 32	CAD 40	CAD 36

Pensions and Other Benefits - I

Pensions and Other Benefits - Information About DB Pension Plans and Other Benefits (Detail) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Change in fund assets:
Fair value of fund assets, Beginning	CAD 12,196
Fair value of fund assets, Ending	12,808	CAD 12,196
Pension Plans, Defined Benefit [Member]
Change in projected benefit obligation:
Benefit obligation at January 1	11,399	11,194
Current service cost	103	106	CAD 126
Interest cost	451	467	463
Employee contributions	44	40
Benefits paid	(648)	(645)
Foreign currency changes	(15)	(7)
Plan amendments and other	1	6
Actuarial loss (gain)	344	238
Projected benefit obligation at December 31	11,679	11,399	11,194
Change in fund assets:
Fair value of fund assets, Beginning	12,196	12,300
Actual return on fund assets	1,183	461
Employer contributions	46	48
Employee contributions	44	40
Benefits paid	(648)	(645)
Foreign currency changes	(13)	(8)
Fair value of fund assets, Ending	12,808	12,196	12,300
Funded status – plan surplus (deficit)	1,129	797
Other Postretirement Benefit Plans, Defined Benefit [Member]
Change in projected benefit obligation:
Benefit obligation at January 1	510	513
Current service cost	12	11	12
Interest cost	20	21	21
Employee contributions	1	1
Benefits paid	(35)	(31)
Foreign currency changes	(3)	0
Plan amendments and other	0	0
Actuarial loss (gain)	13	(5)
Projected benefit obligation at December 31	518	510	513
Change in fund assets:
Fair value of fund assets, Beginning	5	6
Actual return on fund assets	(1)	(1)
Employer contributions	34	30
Employee contributions	1	1
Benefits paid	(35)	(31)
Foreign currency changes	0	0
Fair value of fund assets, Ending	4	5	CAD 6
Pension plans in deficit [Member] | Pension Plans, Defined Benefit [Member]
Change in projected benefit obligation:
Benefit obligation at January 1	497
Projected benefit obligation at December 31	505	497
Change in fund assets:
Fair value of fund assets, Beginning	224
Fair value of fund assets, Ending	227	224
Funded status – plan surplus (deficit)	(278)	(273)
Pension plans in deficit [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Change in fund assets:
Funded status – plan surplus (deficit)	CAD (514)	CAD (505)

Pensions and Other Benefits - P

Pensions and Other Benefits - Pension Plan Asset (Detail) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Fair value of fund assets at December 31	CAD 12,808	CAD 12,196
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation at December 31	(11,679)	(11,399)	CAD (11,194)
Fair value of fund assets at December 31	12,808	12,196	CAD 12,300
Funded Status	1,129	797
Pension plans in surplus [Member] | Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation at December 31	(11,174)	(10,902)
Fair value of fund assets at December 31	12,581	11,972
Funded Status	1,407	1,070
Pension plans in deficit [Member] | Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation at December 31	(505)	(497)
Fair value of fund assets at December 31	227	224
Funded Status	CAD (278)	CAD (273)

Pensions and Other Benefits 107

Pensions and Other Benefits - Amounts Recognized in Company's Consolidated Balance Sheets (Detail) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Pension asset	CAD 1,407	CAD 1,070
Pension and other benefit liabilities	(749)	(734)
Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Pension asset	1,407	1,070
Accounts payable and accrued liabilities	(10)	(10)
Pension and other benefit liabilities	(268)	(263)
Total amount recognized	1,129	797
Other Postretirement Benefit Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Pension asset	0	0
Accounts payable and accrued liabilities	(33)	(34)
Pension and other benefit liabilities	(481)	(471)
Total amount recognized	CAD (514)	CAD (505)

Pensions and Other Benefits 108

Pensions and Other Benefits - Amounts Recognized in Accumulated Other Comprehensive Losses (Detail) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Amounts recognized in accumulated other comprehensive loss	CAD 1,761	CAD 1,822
Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Other than deferred investment gains	2,555	2,842
Deferred investment gains	(178)	(366)
Prior service cost	(2)	(7)
Deferred income tax	(676)	(699)
Amounts recognized in accumulated other comprehensive loss	1,699	1,770
Other Postretirement Benefit Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Other than deferred investment gains	81	66
Deferred investment gains	0	0
Prior service cost	2	3
Deferred income tax	(21)	(17)
Amounts recognized in accumulated other comprehensive loss	CAD 62	CAD 52

Pensions and Other Benefits 109

Pensions and Other Benefits - Actuarial Assumptions Used (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Discount rate	3.80%	4.02%	4.22%
Projected future salary increases	2.75%	2.75%	3.00%
Health care cost trend rate	7.00%	7.00%	7.00%
Discount rate	4.02%	4.22%	4.09%
Expected rate of return on fund assets	7.75%	7.75%	7.75%
Projected future salary increases	2.75%	3.00%	3.00%
Health care cost trend rate change	0.50%	0.50%
Ultimate rate	5.00%	5.00%
Health care cost trend rate previously assumed		6.50%
Heath care cost trend rate previously assumed two years prior			7.00%

Pensions and Other Benefits - S

Pensions and Other Benefits - Summary of Impact of One-Percentage Point Change in Assumed Health Care Cost Trend Rates (Detail)	12 Months Ended
	Dec. 31, 2017CAD
Retirement Benefits [Abstract]
Effect of one percentage point increase on the total of service and interest costs	CAD 0
Effect of one percentage point decrease on the total of service and interest costs	0
Effect of one percentage point increase on post-retirement benefit obligation	(6,000,000)
Effect of one percentage point decrease on post-retirement benefit obligation	CAD 6,000,000

Pensions and Other Benefits 111

Pensions and Other Benefits - Summary of Pension Plan Asset Allocation and Current Weighted Average Policy Range (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Current asset allocation target	100.00%
Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan asset allocation percentages	100.00%	100.00%
Cash and cash equivalents
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Current asset allocation target	0.50%
Cash and cash equivalents | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan asset allocation percentages	1.40%	1.10%
Fixed income
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Current asset allocation target	29.50%
Fixed income | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan asset allocation percentages	26.10%	21.40%
Public equity
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Current asset allocation target	46.00%
Public equity | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan asset allocation percentages	53.30%	53.80%
Real estate and infrastructure
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Current asset allocation target	12.00%
Real estate and infrastructure | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan asset allocation percentages	6.20%	7.50%
Absolute return
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Current asset allocation target	12.00%
Absolute return | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plan asset allocation percentages	13.00%	16.20%
Maximum [Member] | Cash and cash equivalents | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Target asset allocation percentages	0.05
Maximum [Member] | Fixed income | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Target asset allocation percentages	0.4
Maximum [Member] | Public equity | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Target asset allocation percentages	0.55
Maximum [Member] | Real estate and infrastructure | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Target asset allocation percentages	0.2
Maximum [Member] | Absolute return | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Target asset allocation percentages	0.18
Minimum [Member] | Cash and cash equivalents | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Target asset allocation percentages	0
Minimum [Member] | Fixed income | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Target asset allocation percentages	0.2
Minimum [Member] | Public equity | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Target asset allocation percentages	0.35
Minimum [Member] | Real estate and infrastructure | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Target asset allocation percentages	.04
Minimum [Member] | Absolute return | Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Target asset allocation percentages	0

Pensions and Other Benefits 112

Pensions and Other Benefits - Summary of Defined Benefit Pension Plan Assets at Fair Value (Detail) - CAD	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	CAD 12,808,000,000	CAD 12,196,000,000
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	176,000,000	132,000,000
Government bonds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	2,087,000,000	1,357,000,000
Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	1,215,000,000	1,186,000,000
Mortgages
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	45,000,000	71,000,000
Real Estate
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	622,000,000	625,000,000
Fund value subject to redemption	542,000,000	134,000,000
Fund Value Not Subject to Redemption	80,000,000	54,000,000
Unfunded commitments	53,000,000	81,000,000
Derivative assets
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	7,000,000
Derivative, Notional Amount	0	937,000,000
Absolute return
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	1,662,000,000	1,975,000,000
Absolute return | Funds of hedge funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	681,000,000	668,000,000
Absolute return | Multi-strategy funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	515,000,000	502,000,000
Absolute return | Credit funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	252,000,000	505,000,000
Absolute return | Equity funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	CAD 214,000,000	300,000,000
Funds of hedge funds | Funds of hedge funds
Defined Benefit Plan Disclosure [Line Items]
Notice period	95 days
Multi-strategy funds | Multi-strategy funds
Defined Benefit Plan Disclosure [Line Items]
Notice period	60 days
Credit funds (fixed income) | Credit funds
Defined Benefit Plan Disclosure [Line Items]
Notice period	60 days
Equity Funds, Quarterly Redemption [Member] | Equity funds
Defined Benefit Plan Disclosure [Line Items]
Notice period	60 days
Equity Funds, Tri-annual Redemption [Member] | Equity funds
Defined Benefit Plan Disclosure [Line Items]
Notice period	45 days
Infrastructure
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	CAD 176,000,000	285,000,000
Portion at Other than Fair Value Measurement [Member]
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	2,460,000,000	2,448,000,000
Portion at Other than Fair Value Measurement [Member] | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Portion at Other than Fair Value Measurement [Member] | Government bonds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Portion at Other than Fair Value Measurement [Member] | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Portion at Other than Fair Value Measurement [Member] | Mortgages
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Portion at Other than Fair Value Measurement [Member] | Real Estate
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	622,000,000	188,000,000
Portion at Other than Fair Value Measurement [Member] | Derivative assets
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Portion at Other than Fair Value Measurement [Member] | Absolute return | Funds of hedge funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	681,000,000	668,000,000
Portion at Other than Fair Value Measurement [Member] | Absolute return | Multi-strategy funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	515,000,000	502,000,000
Portion at Other than Fair Value Measurement [Member] | Absolute return | Credit funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	252,000,000	505,000,000
Portion at Other than Fair Value Measurement [Member] | Absolute return | Equity funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	214,000,000	300,000,000
Portion at Other than Fair Value Measurement [Member] | Infrastructure
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	176,000,000	285,000,000
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	6,886,000,000	6,586,000,000
Fair Value, Inputs, Level 1 [Member] | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	165,000,000	121,000,000
Fair Value, Inputs, Level 1 [Member] | Government bonds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 1 [Member] | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 1 [Member] | Mortgages
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 1 [Member] | Real Estate
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 1 [Member] | Derivative assets
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 1 [Member] | Absolute return | Funds of hedge funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 1 [Member] | Absolute return | Multi-strategy funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 1 [Member] | Absolute return | Credit funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 1 [Member] | Absolute return | Equity funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 1 [Member] | Infrastructure
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	3,462,000,000	2,725,000,000
Fair Value, Inputs, Level 2 [Member] | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	11,000,000	11,000,000
Fair Value, Inputs, Level 2 [Member] | Government bonds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	2,087,000,000	1,357,000,000
Fair Value, Inputs, Level 2 [Member] | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	1,215,000,000	1,186,000,000
Fair Value, Inputs, Level 2 [Member] | Mortgages
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	45,000,000	71,000,000
Fair Value, Inputs, Level 2 [Member] | Real Estate
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 2 [Member] | Derivative assets
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	7,000,000
Fair Value, Inputs, Level 2 [Member] | Absolute return | Funds of hedge funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 2 [Member] | Absolute return | Multi-strategy funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 2 [Member] | Absolute return | Credit funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 2 [Member] | Absolute return | Equity funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 2 [Member] | Infrastructure
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	437,000,000
Fair Value, Inputs, Level 3 [Member] | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 3 [Member] | Government bonds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 3 [Member] | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 3 [Member] | Mortgages
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 3 [Member] | Real Estate
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	437,000,000
Fair Value, Inputs, Level 3 [Member] | Derivative assets
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 3 [Member] | Absolute return | Funds of hedge funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 3 [Member] | Absolute return | Multi-strategy funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 3 [Member] | Absolute return | Credit funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 3 [Member] | Absolute return | Equity funds
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Fair Value, Inputs, Level 3 [Member] | Infrastructure
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Canada [Member] | Public equity
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	1,529,000,000	1,537,000,000
Canada [Member] | Portion at Other than Fair Value Measurement [Member] | Public equity
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
Canada [Member] | Fair Value, Inputs, Level 1 [Member] | Public equity
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	1,467,000,000	1,480,000,000
Canada [Member] | Fair Value, Inputs, Level 2 [Member] | Public equity
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	62,000,000	57,000,000
Canada [Member] | Fair Value, Inputs, Level 3 [Member] | Public equity
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
U.S. and International | Public equity
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	5,296,000,000	5,021,000,000
U.S. and International | Portion at Other than Fair Value Measurement [Member] | Public equity
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	0	0
U.S. and International | Fair Value, Inputs, Level 1 [Member] | Public equity
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	5,254,000,000	4,985,000,000
U.S. and International | Fair Value, Inputs, Level 2 [Member] | Public equity
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	42,000,000	36,000,000
U.S. and International | Fair Value, Inputs, Level 3 [Member] | Public equity
Defined Benefit Plan Disclosure [Line Items]
DB pension plans at fair values	CAD 0	CAD 0

Pensions and Other Benefits 113

Pensions and Other Benefits - Summary of Defined Benefit Pension Plan Assets Measured at Fair Value Using Unobservable Inputs (Detail) - CAD	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of fund assets, Beginning	CAD 12,196,000,000
Fair value of fund assets, Ending	12,808,000,000	CAD 12,196,000,000
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of fund assets, Beginning	12,196,000,000	12,300,000,000
Net realized gains	1,183,000,000	461,000,000
Fair value of fund assets, Ending	12,808,000,000	12,196,000,000
Real Estate
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of fund assets, Beginning	625,000,000
Fair value of fund assets, Ending	622,000,000	625,000,000
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of fund assets, Beginning	437,000,000
Fair value of fund assets, Ending	0	437,000,000
Fair Value, Inputs, Level 3 [Member] | Real Estate
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of fund assets, Beginning	437,000,000
Fair value of fund assets, Ending	0	437,000,000
Fair Value, Inputs, Level 3 [Member] | Real Estate | Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of fund assets, Beginning	437,000,000	451,000,000
Disbursements	(43,000,000)	(36,000,000)
Net realized gains	7,000,000	24,000,000
Decrease in net unrealized gains	(7,000,000)	(2,000,000)
Net transfers (out of) Level 3	(394,000,000)
Fair value of fund assets, Ending	CAD 0	CAD 437,000,000

Pensions and Other Benefits Pen

Pensions and Other Benefits Pensions and Other Benefits - Company Contributions to Pension Plans (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Contributions to Pension Plans [Line Items]
Total Company pension contribution (DB and DC)	CAD 55	CAD 57	CAD 90
Pension Plans, Defined Benefit and Defined Contribution
Contributions to Pension Plans [Line Items]
Contribution by the Company (DB plans)	46	48
Contribution by the Company (DC Plans)	9	9	9
Other Pension Plans, Postretirement or Supplemental Plans, Defined Benefit [Member]
Contributions to Pension Plans [Line Items]
Contribution by the Company (DB plans)	13	12	12
Canadian registered and U.S. qualified DB pension plans | Pension Plans, Defined Benefit and Defined Contribution
Contributions to Pension Plans [Line Items]
Contribution by the Company (DB plans)	CAD 33	CAD 36	CAD 69

Pensions and Other Benefits 115

Pensions and Other Benefits - Summary of Estimated Future Pension and Other Post-retirement Benefit Payments (Detail) CAD in Millions	Dec. 31, 2017CAD
Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
2,018	CAD 609
2,019	614
2,020	620
2,021	625
2,022	631
2023 – 2027	3,220
Other Postretirement Benefit Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
2,018	33
2,019	31
2,020	31
2,021	31
2,022	30
2023 – 2027	CAD 146

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Detail) CAD / shares in Units, CAD in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2017CADshares	Dec. 31, 2017CADCAD / sharesshares	Dec. 31, 2016CADshares	Dec. 31, 2015CADshares
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Stock-based compensation expense (recovery)		CAD 35	CAD 51	CAD 66
Company's closing stock price (in CAD per share) | CAD / shares		CAD 229.66
Performance Share Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Stock-based compensation expense (recovery)		CAD 30	CAD 29	55
Total unrecognized compensation related to share based compensation plans		CAD 20
Expected to be recognized over a weighted-average period		1 year 6 months
Units issued | shares		134,991	147,157
Grant date fair value		CAD 27
Other than options vesting period		3 years
Payout Percentage		160.00%	118.00%
PSUs Vested in Period | shares		82,673
PSU payout amount	CAD 31	CAD 30
Number of trading days		30 days	30 days
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised | shares	133,728	133,728	83,466
Deferred Share Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Stock-based compensation expense (recovery)		CAD (3)	CAD 2	(10)
Total unrecognized compensation related to share based compensation plans		CAD 1
Expected to be recognized over a weighted-average period		1 year 4 months 24 days
Units issued | shares		23,932	31,069
Grant date fair value		CAD 5
Other than options vesting period		48 months
Matching no. of DSU's that may be granted to key employees to meet share ownership target when acquiring Common Shares and DSU's acquired		25.00%
Ownership target threshold		5 years
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised | shares		33,682	87,996
Regular and Performance Stock Options [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Stock-based compensation expense (recovery)		CAD 3	CAD 14	15
Stock Granted, Value, Share-based Compensation, Gross		17	16	18
Total unrecognized compensation related to share based compensation plans		CAD 9
Expected to be recognized over a weighted-average period		1 year 3 months 18 days
Total fair value of shares vested for stock option plan		CAD 14	15	17
Employee Share Purchase Plan [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Stock-based compensation expense (recovery)		CAD 4	CAD 5	CAD 4
Other than options vesting period		1 year
Employer contribution to employee share purchase plan		$1 for every $3 contributed by employees
The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan		6.00%
Ratio employer matches per dollar contributed		0.3333
Total number of shares purchased on behalf of participants | shares		130,041	140,560	131,703
Employer contributions		CAD 5	CAD 5	CAD 5
Chief Executive Officer [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Employee Benefits and Share-based Compensation		(51)
Pension and Other Postretirement Benefits Cost (Reversal of Cost)		CAD (27)
Chief Executive Officer [Member] | Performance Share Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Forfeited awards other than Options, Number of Shares | shares		22,514
Chief Executive Officer [Member] | Deferred Share Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Forfeited awards other than Options, Number of Shares | shares		68,612
Chief Executive Officer [Member] | Regular and Performance Stock Options [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share-based Compensation Arrangement by Share-base Payment Award, Options, Vested and Nonvested Options Forfeited, Number of Shares | shares		752,145

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option Plan (Detail) - CAD CAD / shares in Units, CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Number of options, Options outstanding (in shares)
Outstanding, January 1	2,450,082
Granted	369,980
Exercised	(536,291)
Forfeited	(803,796)
Expired	(700)
Outstanding, December 31	1,479,275	2,450,082
Vested or expected to vest at December 31	1,419,564
Exercisable, December 31	796,348
Number of options, Nonvested options (in shares)
Outstanding (non-vested) January 1	850,167
Granted	369,980
Vested	(328,265)
Forfeited (non-vested)	(208,955)
Outstanding (non-vested) December 31	682,927	850,167
Weighted average exercise price, Options outstanding
Outstanding, January 1 (in dollars per share)	CAD 121.95
New options granted (in dollars per share)	193.13
Exercised (in dollars per share)	84.93
Forfeited (in dollars per share)	120.97
Expired (in dollars per share)	62.56
Outstanding at December 31 (in dollar per share)	150.64	CAD 121.95
Vested or expected to vest as at December 31 (in dollars per share)	149.05
Exercisable at December 31 (in dollars per share)	119.32
Weighted average grant date fair value, Nonvested options
Outstanding (non-vested), January 1 (in dollars per share)	44.49
Weighted average grant date fair value of options granted during the year (in dollars per share)	45.78	39.01	CAD 55.28
Vested (in dollars per share)	42.97
Forfeited (in dollars per share)	47.21
Outstanding (non-vested), December 31 (in dollars per share)	CAD 45.46	CAD 44.49
Weighted average remaining term of vested or expected to vest options	7 years
Aggregate intrinsic value of vested or expected to vest options	CAD 114

Stock-Based Compensation - S118

Stock-Based Compensation - Stock Options Outstanding and Exercisable (Detail) CAD / shares in Units, CAD in Millions	12 Months Ended
	Dec. 31, 2017CADCAD / sharesshares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, Number of options (in shares) | shares	1,479,275
Options outstanding, Weighted average years to expiration	5 years 8 months 12 days
Options outstanding, Weighted average exercise price (in dollars per share)	CAD 150.64
Options outstanding, Aggregate intrinsic value | CAD	CAD 117
Options exercisable, Number of options (in shares) | shares	796,348
Options exercisable, Weighted average exercise price (in dollars per share)	CAD 119.32
Options outstanding, Aggregate intrinsic value | CAD	CAD 87
Stock options in-the-money (in shares) | shares	1,479,275
Stock options in-the-money weighted average exercise price (in dollars per share)	CAD 150.64
Stock options weighted average contractual Term	4 years 10 months 24 days
Range of exercise prices from $36.29 - $117.48 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of option exercise prices, minimum	CAD 36.29
Range of option exercise prices, maximum	CAD 117.48
Options outstanding, Number of options (in shares) | shares	416,270
Options outstanding, Weighted average years to expiration	3 years 8 months 12 days
Options outstanding, Weighted average exercise price (in dollars per share)	CAD 84.50
Options outstanding, Aggregate intrinsic value | CAD	CAD 60
Options exercisable, Number of options (in shares) | shares	416,270
Options exercisable, Weighted average exercise price (in dollars per share)	CAD 84.50
Options outstanding, Aggregate intrinsic value | CAD	CAD 60
Range of exercise prices from $117.49 - $165.95 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of option exercise prices, minimum	CAD 117.49
Range of option exercise prices, maximum	CAD 165.95
Options outstanding, Number of options (in shares) | shares	359,997
Options outstanding, Weighted average years to expiration	6 years 9 months 18 days
Options outstanding, Weighted average exercise price (in dollars per share)	CAD 141.38
Options outstanding, Aggregate intrinsic value | CAD	CAD 32
Options exercisable, Number of options (in shares) | shares	200,362
Options exercisable, Weighted average exercise price (in dollars per share)	CAD 128.43
Options outstanding, Aggregate intrinsic value | CAD	CAD 20
Range of exercise prices from $165.96 - $190.42 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of option exercise prices, minimum	CAD 165.96
Range of option exercise prices, maximum	CAD 190.42
Options outstanding, Number of options (in shares) | shares	415,914
Options outstanding, Weighted average years to expiration	6 years 1 month 6 days
Options outstanding, Weighted average exercise price (in dollars per share)	CAD 182.48
Options outstanding, Aggregate intrinsic value | CAD	CAD 20
Options exercisable, Number of options (in shares) | shares	106,458
Options exercisable, Weighted average exercise price (in dollars per share)	CAD 169.28
Options outstanding, Aggregate intrinsic value | CAD	CAD 6
Range of exercise prices from $190.43 - $222.88 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of option exercise prices, minimum	CAD 190.43
Range of option exercise prices, maximum	CAD 222.88
Options outstanding, Number of options (in shares) | shares	287,094
Options outstanding, Weighted average years to expiration	6 years 8 months 12 days
Options outstanding, Weighted average exercise price (in dollars per share)	CAD 212.05
Options outstanding, Aggregate intrinsic value | CAD	CAD 5
Options exercisable, Number of options (in shares) | shares	73,258
Options exercisable, Weighted average exercise price (in dollars per share)	CAD 219.60
Options outstanding, Aggregate intrinsic value | CAD	CAD 1

Stock-Based Compensation - Weig

Stock-Based Compensation - Weighted-Average Fair Value Assumptions (Detail) - CAD	May 10, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Expected option life (years)		5 years 5 months 23 days	5 years 3 months	5 years 3 months
Risk-free interest rate		1.85%	1.21%	1.10%
Expected stock price volatility		27.00%	27.00%	26.00%
Expected annual dividends per share (in dollars per share)	CAD 0.5625	CAD 2.0010	CAD 1.4000	CAD 1.4000
Share based Compensation Arrangement by Share based Payment Award, Fair Value Assumptions, Estimated Forfeiture Rate		2.80%	2.00%	1.20%
Weighted average grant date fair value of options granted during the year (in dollars per share)		CAD 45.78	CAD 39.01	CAD 55.28
Expected Annual Dividends		CAD 2.2500

Stock-Based Compensation - Info

Stock-Based Compensation - Information Related to All Options Exercised in Stock Option Plan (Detail) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Total intrinsic value (in dollars per share)	CAD 36	CAD 30	CAD 72
Cash received by the Company upon exercise of options	CAD 45	CAD 21	CAD 43

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Performance Share Units Plan (Detail) - Performance Share Units [Member] - shares	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward] (in shares)
Outstanding, January 1	373,593	373,593	348,276
Granted		134,991	147,157
Units, in lieu of dividends		3,571	4,010
Settled	(133,728)	(133,728)	(83,466)
Forfeited		(44,399)	(42,384)
Outstanding, December 31		334,028	373,593

Stock-Based Compensation - S122

Stock-Based Compensation - Summary of Deferred Share Units Plan (Detail) - Deferred Share Units [Member] - shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] (in shares)
Outstanding, January 1	234,036	318,176
Granted	23,932	31,069
Units, in lieu of dividends	1,969	2,798
Settled	(33,682)	(87,996)
Forfeited	(69,708)	(30,011)
Outstanding, December 31	156,547	234,036

Stock-Based Compensation - S123

Stock-Based Compensation - Summary of Total Share Based Liabilities (Detail) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share based liabilities paid (in dollars per share)	CAD 39	CAD 48	CAD 90
Deferred Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share based liabilities paid (in dollars per share)	6	17	3
Performance Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share based liabilities paid (in dollars per share)	31	31	79
Other share based liabilities [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share based liabilities paid (in dollars per share)	CAD 2	CAD 0	CAD 8

Variable Interest Entities (Det

Variable Interest Entities (Details) CAD in Millions	12 Months Ended
	Dec. 31, 2017CAD
Variable Interest Entity [Line Items]
Future minimum lease payments before tax	CAD 351
Variable Interest Entity [Member]
Variable Interest Entity [Line Items]
Lease payments after tax	10
Future minimum lease payments before tax	CAD 177
Period over which lease payments will be paid	13 years

Commitments and Contingencies -

Commitments and Contingencies - Minimum Future Lease Payments Under Operating Leases (Details) CAD in Millions	Dec. 31, 2017CAD
Commitments and Contingencies Disclosure [Abstract]
2,018	CAD 71
2,019	57
2,020	45
2,021	38
2,022	31
Thereafter	109
Total minimum lease payments	CAD 351

Commitments and Contingencie126

Commitments and Contingencies - Narrative (Details) CAD in Millions	Dec. 28, 2017CAD	Oct. 10, 2017CAD	Jul. 11, 2016CADclaim	Jul. 05, 2016CAD	Jul. 04, 2016CADclaim	Apr. 12, 2016CAD	Jul. 06, 2015CAD	Dec. 31, 2017CAD	Dec. 31, 2016CAD	Dec. 31, 2015CAD
Commitments and Contingencies [Line Items]
Period for which future capital and operating expenditures are committed, beginning year								2,018
Period for which future capital and operating expenditures are committed, end year								2,032
Estimated future purchase commitment								CAD 1,400
Total minimum lease payments								351
Expenses for operating leases								104	CAD 111	CAD 127
Lac-Megantic Rail Incident | Claimed damages as a result of derailment
Commitments and Contingencies [Line Items]
Amount of fund distributed								440
Lac-Megantic Rail Incident | Irving Oil [Member]
Commitments and Contingencies [Line Items]
Value of damages sought						CAD 60
Lac-Megantic Rail Incident | Quebec Minister of Sustainable Development, Environment, Wildlife and Parks
Commitments and Contingencies [Line Items]
Value of damages sought				CAD 95
Lac-Megantic Rail Incident | Quebec Attorney General
Commitments and Contingencies [Line Items]
Value of damages sought		CAD 315					CAD 409
Lac-Megantic Rail Incident | Initial Insurer Claimants | Subrogated insurance claim
Commitments and Contingencies [Line Items]
Value of damages sought	CAD 14				CAD 16
Number of subrogated insurers | claim					8
Lac-Megantic Rail Incident | Additional Insurer Claimants | Subrogated insurance claim
Commitments and Contingencies [Line Items]
Value of damages sought			CAD 3
Number of subrogated insurers | claim			2
Lac-Megantic Rail Incident | The WD Trustee | Damaged railcars loss recovery
Commitments and Contingencies [Line Items]
Value of damages sought						6
Lac-Megantic Rail Incident | Montreal Maine and Atlantic Railway | World Fuel Entities [Member]
Commitments and Contingencies [Line Items]
Value of damages sought						CAD 110
Capital Expenditure [Member]
Commitments and Contingencies [Line Items]
Total future committed expenditure								632
Operating Expenditures [Member]
Commitments and Contingencies [Line Items]
Total future committed expenditure								CAD 1,700

Guarantees (Details)

Guarantees (Details) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016
Guarantees [Abstract]
Residual value guarantees on operating lease commitments	CAD 6
Accrued guarantees recorded in accounts payable and accrued liabilities	CAD 9	CAD 5

Segmented and Geographic Inf128

Segmented and Geographic Information - Narrative (Details) - segment	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting [Abstract]
Number of operating segments	1	1	1
Number of customers that comprise more than 10% of total revenues and accounts receivable	0	0	0

Segmented and Geographic Inf129

Segmented and Geographic Information - Geographic Information (Details) - CAD CAD in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues	CAD 1,713	CAD 1,595	CAD 1,643	CAD 1,603	CAD 1,637	CAD 1,554	CAD 1,450	CAD 1,591	CAD 6,554	CAD 6,232	CAD 6,712
Long-term assets excluding financial instruments and pension assets	17,452				17,121				17,452	17,121	16,698
Canada [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									4,667	4,473	4,662
Long-term assets excluding financial instruments and pension assets	11,505				11,000				11,505	11,000	10,630
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenues									1,887	1,759	2,050
Long-term assets excluding financial instruments and pension assets	CAD 5,947				CAD 6,121				CAD 5,947	CAD 6,121	CAD 6,068

Selected Quarterly Data (Una130

Selected Quarterly Data (Unaudited) (Details) - CAD CAD / shares in Units, CAD in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Total revenues	CAD 1,713	CAD 1,595	CAD 1,643	CAD 1,603	CAD 1,637	CAD 1,554	CAD 1,450	CAD 1,591	CAD 6,554	CAD 6,232	CAD 6,712
Operating income	753	690	679	671	717	657	551	653	2,793	2,578	2,688
Net income	CAD 984	CAD 510	CAD 480	CAD 431	CAD 384	CAD 347	CAD 328	CAD 540	CAD 2,405	CAD 1,599	CAD 1,352
Basic earnings per share	CAD 6.79	CAD 3.50	CAD 3.28	CAD 2.94	CAD 2.63	CAD 2.35	CAD 2.16	CAD 3.53	CAD 16.49	CAD 10.69	CAD 8.47
Diluted earnings per share	CAD 6.77	CAD 3.50	CAD 3.27	CAD 2.93	CAD 2.61	CAD 2.34	CAD 2.15	CAD 3.51	CAD 16.44	CAD 10.63	CAD 8.40

Condensed Consolidating Fina131

Condensed Consolidating Financial Information - Condensed Consolidating Statements of Income (Detail) - CAD CAD in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues
Freight									CAD 6,375	CAD 6,060	CAD 6,552
Non-freight									179	172	160
Total revenues	CAD 1,713	CAD 1,595	CAD 1,643	CAD 1,603	CAD 1,637	CAD 1,554	CAD 1,450	CAD 1,591	6,554	6,232	6,712
Operating expenses
Compensation and benefits									1,035	1,189	1,371
Fuel									677	567	708
Materials									190	180	184
Equipment rents									142	173	174
Depreciation and amortization									661	640	595
Purchased Services and Other									1,056	905	1,060
Gain on sale of Delaware & Hudson South									0	0	(68)
Total operating expenses									3,761	3,654	4,024
Operating income	753	690	679	671	717	657	551	653	2,793	2,578	2,688
Less:
Other income and charges									(178)	(45)	335
Net interest expense (income)									473	471	394
Income before income tax expense									2,498	2,152	1,959
Less: Income tax expense (recovery)									93	553	607
Add: Equity in net earnings of subsidiaries									0	0	0
Net income	CAD 984	CAD 510	CAD 480	CAD 431	CAD 384	CAD 347	CAD 328	CAD 540	2,405	1,599	1,352
Consolidating Adjustments and Eliminations [Member]
Revenues
Freight									0	0	0
Non-freight									(333)	(348)	(331)
Total revenues									(333)	(348)	(331)
Operating expenses
Compensation and benefits									7	6	0
Fuel									0	0	0
Materials									15	18	0
Equipment rents									0	0	0
Depreciation and amortization									0	0	0
Purchased Services and Other									(355)	(372)	(331)
Gain on sale of Delaware & Hudson South											0
Total operating expenses									(333)	(348)	(331)
Operating income									0	0	0
Less:
Other income and charges									0	0	0
Net interest expense (income)									0	0	0
Income before income tax expense									0	0	0
Less: Income tax expense (recovery)									0	0	0
Add: Equity in net earnings of subsidiaries									(3,547)	(2,098)	(2,175)
Net income									(3,547)	(2,098)	(2,175)
CPRL (Parent Guarantor) [Member] | Reportable Legal Entities [Member]
Revenues
Freight									0	0	0
Non-freight									0	0	0
Total revenues									0	0	0
Operating expenses
Compensation and benefits									0	0	0
Fuel									0	0	0
Materials									0	0	0
Equipment rents									0	0	0
Depreciation and amortization									0	0	0
Purchased Services and Other									0	0	0
Gain on sale of Delaware & Hudson South											0
Total operating expenses									0	0	0
Operating income									0	0	0
Less:
Other income and charges									(33)	(40)	84
Net interest expense (income)									(12)	1	(5)
Income before income tax expense									45	39	(79)
Less: Income tax expense (recovery)									7	6	(21)
Add: Equity in net earnings of subsidiaries									2,367	1,566	1,410
Net income									2,405	1,599	1,352
CPRC (Subsidiary Issuer) [Member] | Reportable Legal Entities [Member]
Revenues
Freight									4,516	4,332	4,532
Non-freight									140	134	128
Total revenues									4,656	4,466	4,660
Operating expenses
Compensation and benefits									601	749	943
Fuel									522	458	549
Materials									134	130	148
Equipment rents									143	204	181
Depreciation and amortization									400	422	411
Purchased Services and Other									826	673	711
Gain on sale of Delaware & Hudson South											0
Total operating expenses									2,626	2,636	2,943
Operating income									2,030	1,830	1,717
Less:
Other income and charges									(149)	(34)	322
Net interest expense (income)									517	493	447
Income before income tax expense									1,662	1,371	948
Less: Income tax expense (recovery)									475	337	303
Add: Equity in net earnings of subsidiaries									1,180	532	765
Net income									2,367	1,566	1,410
Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Revenues
Freight									1,859	1,728	2,020
Non-freight									372	386	363
Total revenues									2,231	2,114	2,383
Operating expenses
Compensation and benefits									427	434	428
Fuel									155	109	159
Materials									41	32	36
Equipment rents									(1)	(31)	(7)
Depreciation and amortization									261	218	184
Purchased Services and Other									585	604	680
Gain on sale of Delaware & Hudson South											(68)
Total operating expenses									1,468	1,366	1,412
Operating income									763	748	971
Less:
Other income and charges									4	29	(71)
Net interest expense (income)									(32)	(23)	(48)
Income before income tax expense									791	742	1,090
Less: Income tax expense (recovery)									(389)	210	325
Add: Equity in net earnings of subsidiaries									0	0	0
Net income									CAD 1,180	CAD 532	CAD 765

Condensed Consolidating Fina132

Condensed Consolidating Financial Information - Condensed Consolidating Statements of Comprehensive Income (Detail) - CAD CAD in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Net income	CAD 984	CAD 510	CAD 480	CAD 431	CAD 384	CAD 347	CAD 328	CAD 540	CAD 2,405	CAD 1,599	CAD 1,352
Net gain (loss) in foreign currency translation adjustments, net of hedging activities									24	18	(86)
Change in derivatives designated as cash flow hedges									19	(2)	(69)
Change in pension and post-retirement defined benefit plans									80	(434)	1,059
Other comprehensive income (loss) before income taxes									123	(418)	904
Income tax (expense) recovery on above items									(65)	96	(162)
Equity accounted investments									0	0	0
Other comprehensive income (loss)									58	(322)	742
Comprehensive income									2,463	1,277	2,094
Consolidating Adjustments and Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net income									(3,547)	(2,098)	(2,175)
Net gain (loss) in foreign currency translation adjustments, net of hedging activities									0	0	0
Change in derivatives designated as cash flow hedges									0	0	0
Change in pension and post-retirement defined benefit plans									0	0	0
Other comprehensive income (loss) before income taxes									0	0	0
Income tax (expense) recovery on above items									0	0	0
Equity accounted investments									237	447	(1,412)
Other comprehensive income (loss)									237	447	(1,412)
Comprehensive income									(3,310)	(1,651)	(3,587)
CPRL (Parent Guarantor) [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements, Captions [Line Items]
Net income									2,405	1,599	1,352
Net gain (loss) in foreign currency translation adjustments, net of hedging activities									0	0	0
Change in derivatives designated as cash flow hedges									0	0	0
Change in pension and post-retirement defined benefit plans									0	0	0
Other comprehensive income (loss) before income taxes									0	0	0
Income tax (expense) recovery on above items									0	0	0
Equity accounted investments									58	(322)	742
Other comprehensive income (loss)									58	(322)	742
Comprehensive income									2,463	1,277	2,094
CPRC (Subsidiary Issuer) [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements, Captions [Line Items]
Net income									2,367	1,566	1,410
Net gain (loss) in foreign currency translation adjustments, net of hedging activities									318	149	(757)
Change in derivatives designated as cash flow hedges									19	(2)	(69)
Change in pension and post-retirement defined benefit plans									82	(443)	1,061
Other comprehensive income (loss) before income taxes									419	(296)	235
Income tax (expense) recovery on above items									(66)	99	(163)
Equity accounted investments									(295)	(125)	670
Other comprehensive income (loss)									58	(322)	742
Comprehensive income									2,425	1,244	2,152
Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements, Captions [Line Items]
Net income									1,180	532	765
Net gain (loss) in foreign currency translation adjustments, net of hedging activities									(294)	(131)	671
Change in derivatives designated as cash flow hedges									0	0	0
Change in pension and post-retirement defined benefit plans									(2)	9	(2)
Other comprehensive income (loss) before income taxes									(296)	(122)	669
Income tax (expense) recovery on above items									1	(3)	1
Equity accounted investments									0	0	0
Other comprehensive income (loss)									(295)	(125)	670
Comprehensive income									CAD 885	CAD 407	CAD 1,435

Condensed Consolidating Fina133

Condensed Consolidating Financial Information - Condensed Consolidating Balance Sheets (Detail) - CAD CAD in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	CAD 338	CAD 164
Accounts receivable, net	687	591
Accounts receivable, intercompany	0	0
Short-term advances to affiliates	0	0
Materials and supplies	152	184
Other current assets	97	70
Total current assets	1,274	1,009
Long-term advances to affiliates	0	0
Investments	182	194
Investments in subsidiaries	0	0
Properties	17,016	16,689
Goodwill and intangible assets	187	202	CAD 211
Pension asset	1,407	1,070
Other assets	69	57
Deferred income taxes	0	0
Total assets	20,135	19,221
Current liabilities
Accounts payable and accrued liabilities	1,238	1,322
Due to Related Parties, Current	0	0
Short-term advances from affiliates	0	0
Long-term debt maturing within one year	746	25
Total current liabilities	1,984	1,347
Pension and other benefit liabilities	749	734
Long-term advances from affiliates	0	0
Other long-term liabilities	231	284
Long-term debt	7,413	8,659
Deferred income taxes	3,321	3,571
Total liabilities	13,698	14,595
Shareholders’ equity
Share capital	2,032	2,002
Additional paid-in capital	43	52
Accumulated other comprehensive (loss) income	(1,741)	(1,799)	(1,477)
Retained earnings	6,103	4,371
Total Shareholders' equity	6,437	4,626	CAD 4,796	CAD 5,610
Total liabilities and shareholders’ equity	20,135	19,221
Consolidating Adjustments and Eliminations [Member]
Current assets
Cash and cash equivalents	0	0
Accounts receivable, net	0	0
Accounts receivable, intercompany	(465)	(409)
Short-term advances to affiliates	(6,500)	(5,227)
Materials and supplies	0	0
Other current assets	0	0
Total current assets	(6,965)	(5,636)
Long-term advances to affiliates	(1,000)	(92)
Investments	0	0
Investments in subsidiaries	(22,745)	(18,762)
Properties	0	0
Goodwill and intangible assets	0	0
Pension asset	0	0
Other assets	0	0
Deferred income taxes	(3)	(11)
Total assets	(30,713)	(24,501)
Current liabilities
Accounts payable and accrued liabilities	0	0
Due to Related Parties, Current	(465)	(409)
Short-term advances from affiliates	(6,500)	(5,227)
Long-term debt maturing within one year	0	0
Total current liabilities	(6,965)	(5,636)
Pension and other benefit liabilities	0	0
Long-term advances from affiliates	(1,000)	(92)
Other long-term liabilities	0	0
Long-term debt	0	0
Deferred income taxes	(3)	(11)
Total liabilities	(7,968)	(5,739)
Shareholders’ equity
Share capital	(7,767)	(6,860)
Additional paid-in capital	(1,902)	(1,936)
Accumulated other comprehensive (loss) income	1,325	1,087
Retained earnings	(14,401)	(11,053)
Total Shareholders' equity	(22,745)	(18,762)
Total liabilities and shareholders’ equity	(30,713)	(24,501)
CPRL (Parent Guarantor) [Member] | Reportable Legal Entities [Member]
Current assets
Cash and cash equivalents	0	0
Accounts receivable, net	0	0
Accounts receivable, intercompany	97	90
Short-term advances to affiliates	500	500
Materials and supplies	0	0
Other current assets	0	0
Total current assets	597	590
Long-term advances to affiliates	590	1
Investments	0	0
Investments in subsidiaries	10,623	8,513
Properties	0	0
Goodwill and intangible assets	0	0
Pension asset	0	0
Other assets	0	1
Deferred income taxes	3	11
Total assets	11,813	9,116
Current liabilities
Accounts payable and accrued liabilities	82	73
Due to Related Parties, Current	3	14
Short-term advances from affiliates	5,291	4,403
Long-term debt maturing within one year	0	0
Total current liabilities	5,376	4,490
Pension and other benefit liabilities	0	0
Long-term advances from affiliates	0	0
Other long-term liabilities	0	0
Long-term debt	0	0
Deferred income taxes	0	0
Total liabilities	5,376	4,490
Shareholders’ equity
Share capital	2,032	2,002
Additional paid-in capital	43	52
Accumulated other comprehensive (loss) income	(1,741)	(1,799)
Retained earnings	6,103	4,371
Total Shareholders' equity	6,437	4,626
Total liabilities and shareholders’ equity	11,813	9,116
CPRC (Subsidiary Issuer) [Member] | Reportable Legal Entities [Member]
Current assets
Cash and cash equivalents	241	100
Accounts receivable, net	508	435
Accounts receivable, intercompany	153	113
Short-term advances to affiliates	1,004	692
Materials and supplies	120	150
Other current assets	31	38
Total current assets	2,057	1,528
Long-term advances to affiliates	0	0
Investments	27	47
Investments in subsidiaries	12,122	10,249
Properties	8,982	8,756
Goodwill and intangible assets	0	0
Pension asset	1,407	1,070
Other assets	56	48
Deferred income taxes	0	0
Total assets	24,651	21,698
Current liabilities
Accounts payable and accrued liabilities	844	945
Due to Related Parties, Current	309	292
Short-term advances from affiliates	1,185	816
Long-term debt maturing within one year	746	25
Total current liabilities	3,084	2,078
Pension and other benefit liabilities	672	658
Long-term advances from affiliates	1,000	92
Other long-term liabilities	108	152
Long-term debt	7,362	8,605
Deferred income taxes	1,802	1,600
Total liabilities	14,028	13,185
Shareholders’ equity
Share capital	1,037	1,037
Additional paid-in capital	1,643	1,638
Accumulated other comprehensive (loss) income	(1,742)	(1,799)
Retained earnings	9,685	7,637
Total Shareholders' equity	10,623	8,513
Total liabilities and shareholders’ equity	24,651	21,698
Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Current assets
Cash and cash equivalents	97	64
Accounts receivable, net	179	156
Accounts receivable, intercompany	215	206
Short-term advances to affiliates	4,996	4,035
Materials and supplies	32	34
Other current assets	66	32
Total current assets	5,585	4,527
Long-term advances to affiliates	410	91
Investments	155	147
Investments in subsidiaries	0	0
Properties	8,034	7,933
Goodwill and intangible assets	187	202
Pension asset	0	0
Other assets	13	8
Deferred income taxes	0	0
Total assets	14,384	12,908
Current liabilities
Accounts payable and accrued liabilities	312	304
Due to Related Parties, Current	153	103
Short-term advances from affiliates	24	8
Long-term debt maturing within one year	0	0
Total current liabilities	489	415
Pension and other benefit liabilities	77	76
Long-term advances from affiliates	0	0
Other long-term liabilities	123	132
Long-term debt	51	54
Deferred income taxes	1,522	1,982
Total liabilities	2,262	2,659
Shareholders’ equity
Share capital	6,730	5,823
Additional paid-in capital	259	298
Accumulated other comprehensive (loss) income	417	712
Retained earnings	4,716	3,416
Total Shareholders' equity	12,122	10,249
Total liabilities and shareholders’ equity	CAD 14,384	CAD 12,908

Condensed Consolidating Fina134

Condensed Consolidating Financial Information - Condensed Consolidating Statements of Cash Flows (Detail) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Cash provided by operating activities	CAD 2,182	CAD 2,089	CAD 2,459
Investing activities
Additions to properties	(1,340)	(1,182)	(1,522)
Proceeds from the sale of property, plant and equipment	0	0	281
Proceeds from sale of properties and other assets	42	116	114
Advances to affiliates	0	0	0
Repayment of advances to affiliates	0	0	0
Capital contributions to affiliates	0	0	0
Repurchase of share capital from affiliates	0	0	0
Other	3	(3)	4
Cash used in investing activities	(1,295)	(1,069)	(1,123)
Financing activities
Dividends paid	(310)	(255)	(226)
Issuance of share capital	0	0	0
Return of share capital to affiliates	0	0	0
Issuance of CP Common Shares	45	21	43
Purchase of CP Common shares	(381)	(1,210)	(2,787)
Issuance of long-term debt, excluding commercial paper	0	0	3,411
Repayment of long-term debt, excluding commercial paper	(32)	(38)	(505)
Net repayment of commercial paper	0	(8)	(893)
Advances from affiliates	0	0	0
Repayment of advances from affiliates	0	0	0
Settlement of forward starting swaps	(22)	0	0
Other	0	(3)	0
Cash used in financing activities	(700)	(1,493)	(957)
Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents	(13)	(13)	45
Cash position
Increase (decrease) in cash and cash equivalents	174	(486)	424
Cash and cash equivalents at beginning of year	164	650	226
Cash and cash equivalents at end of year	338	164	650
Consolidating Adjustments and Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by operating activities	(479)	(469)	(2,548)
Investing activities
Additions to properties	0	0	0
Proceeds from the sale of property, plant and equipment			0
Proceeds from sale of properties and other assets	0	0	0
Advances to affiliates	2,668	1,203	3,264
Repayment of advances to affiliates	(485)	(222)	(1,804)
Capital contributions to affiliates	1,039	472	1,655
Repurchase of share capital from affiliates	(156)	(8)	(1,210)
Other	0	0	0
Cash used in investing activities	3,066	1,445	1,905
Financing activities
Dividends paid	479	469	2,548
Issuance of share capital	(1,039)	(472)	(1,655)
Return of share capital to affiliates	156	8	1,210
Issuance of CP Common Shares	0	0	0
Purchase of CP Common shares	0	0	0
Issuance of long-term debt, excluding commercial paper			0
Repayment of long-term debt, excluding commercial paper	0	0	0
Net repayment of commercial paper		0	0
Advances from affiliates	(2,668)	(1,203)	(3,264)
Repayment of advances from affiliates	485	222	1,804
Settlement of forward starting swaps	0
Other		0
Cash used in financing activities	(2,587)	(976)	643
Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents	0	0	0
Cash position
Increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	0	0	0
CPRL (Parent Guarantor) [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by operating activities	338	255	2,283
Investing activities
Additions to properties	0	0	0
Proceeds from the sale of property, plant and equipment			0
Proceeds from sale of properties and other assets	0	0	0
Advances to affiliates	(590)	0	(1,133)
Repayment of advances to affiliates	0	0	0
Capital contributions to affiliates	0	0	0
Repurchase of share capital from affiliates	0	0	0
Other	0	0	0
Cash used in investing activities	(590)	0	(1,133)
Financing activities
Dividends paid	(310)	(255)	(226)
Issuance of share capital	0	0	0
Return of share capital to affiliates	0	0	0
Issuance of CP Common Shares	45	21	43
Purchase of CP Common shares	(381)	(1,210)	(2,787)
Issuance of long-term debt, excluding commercial paper			0
Repayment of long-term debt, excluding commercial paper	0	0	0
Net repayment of commercial paper		0	0
Advances from affiliates	1,383	1,189	1,820
Repayment of advances from affiliates	(485)	0	0
Settlement of forward starting swaps	0
Other		0
Cash used in financing activities	252	(255)	(1,150)
Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents	0	0	0
Cash position
Increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	0	0	0
CPRC (Subsidiary Issuer) [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by operating activities	1,334	1,424	1,650
Investing activities
Additions to properties	(950)	(728)	(766)
Proceeds from the sale of property, plant and equipment			0
Proceeds from sale of properties and other assets	29	102	103
Advances to affiliates	(550)	(664)	(311)
Repayment of advances to affiliates	242	222	804
Capital contributions to affiliates	(1,039)	(472)	(1,655)
Repurchase of share capital from affiliates	156	8	1,210
Other	5	0	6
Cash used in investing activities	(2,107)	(1,532)	(609)
Financing activities
Dividends paid	(310)	(255)	(2,272)
Issuance of share capital	0	0	0
Return of share capital to affiliates	0	0	0
Issuance of CP Common Shares	0	0	0
Purchase of CP Common shares	0	0	0
Issuance of long-term debt, excluding commercial paper			3,411
Repayment of long-term debt, excluding commercial paper	(32)	(24)	(461)
Net repayment of commercial paper		(8)	(893)
Advances from affiliates	1,285	0	500
Repayment of advances from affiliates	0	0	(1,000)
Settlement of forward starting swaps	(22)
Other		(3)
Cash used in financing activities	921	(290)	(715)
Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents	(7)	(4)	24
Cash position
Increase (decrease) in cash and cash equivalents	141	(402)	350
Cash and cash equivalents at beginning of year	100	502	152
Cash and cash equivalents at end of year	241	100	502
Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by operating activities	989	879	1,074
Investing activities
Additions to properties	(390)	(454)	(756)
Proceeds from the sale of property, plant and equipment			281
Proceeds from sale of properties and other assets	13	14	11
Advances to affiliates	(1,528)	(539)	(1,820)
Repayment of advances to affiliates	243	0	1,000
Capital contributions to affiliates	0	0	0
Repurchase of share capital from affiliates	0	0	0
Other	(2)	(3)	(2)
Cash used in investing activities	(1,664)	(982)	(1,286)
Financing activities
Dividends paid	(169)	(214)	(276)
Issuance of share capital	1,039	472	1,655
Return of share capital to affiliates	(156)	(8)	(1,210)
Issuance of CP Common Shares	0	0	0
Purchase of CP Common shares	0	0	0
Issuance of long-term debt, excluding commercial paper			0
Repayment of long-term debt, excluding commercial paper	0	(14)	(44)
Net repayment of commercial paper		0	0
Advances from affiliates	0	14	944
Repayment of advances from affiliates	0	(222)	(804)
Settlement of forward starting swaps	0
Other		0
Cash used in financing activities	714	28	265
Effect of foreign currency fluctuations on U.S. dollar-denominated cash and cash equivalents	(6)	(9)	21
Cash position
Increase (decrease) in cash and cash equivalents	33	(84)	74
Cash and cash equivalents at beginning of year	64	148	74
Cash and cash equivalents at end of year	CAD 97	CAD 64	CAD 148

Schedule II - Valuation and 135

Schedule II - Valuation and Qualifying Accounts (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accruals for legal, personal injury and casualty-related claims [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance at January 1	CAD 130	CAD 133	CAD 150
Additions charged to expenses	66	67	79
Payments and other reductions	(77)	(71)	(102)
Impact of FX	(1)	1	6
Ending balance at December 31	118	130	133
Environmental liabilities [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance at January 1	85	93	91
Additions charged to expenses	5	6	7
Payments and other reductions	(8)	(12)	(17)
Impact of FX	(4)	(2)	12
Ending balance at December 31	CAD 78	CAD 85	CAD 93