Commitments and Contingencies - Narrative (Details) - 12 months ended Dec. 31, 2019 $ in Millions, $ in Millions	CAD ($) claim	USD ($) claim
Commitments and Contingencies [Line Items]
Period for which future capital and operating expenditures are committed, beginning year	2020	2020
Period for which future capital and operating expenditures are committed, end year	2032	2032
Estimated future purchase commitment, next 5 years	$ 2,700
Lac-Megantic Rail Accident \| Claimed damages as a result of derailment
Commitments and Contingencies [Line Items]
Amount to be distributed	440
Lac-Megantic Rail Accident \| Quebec Minister of Sustainable Development, Environment, Wildlife and Parks
Commitments and Contingencies [Line Items]
Value of damages sought	95
Lac-Megantic Rail Accident \| Attorney General of Quebec
Commitments and Contingencies [Line Items]
Value of damages sought	315
Loss Contingency, Damages Sought Previously, Value	409
Lac-Megantic Rail Accident \| Initial Subrogated Insurers \| Subrogated insurance claim
Commitments and Contingencies [Line Items]
Value of damages sought	14
Loss Contingency, Damages Sought Previously, Value	$ 16
Number of subrogated insurer claims \| claim	8
Lac-Megantic Rail Accident \| Additional Subrogated Insurers \| Subrogated insurance claim
Commitments and Contingencies [Line Items]
Value of damages sought	$ 3
Number of subrogated insurer claims \| claim	2
Lac-Megantic Rail Accident \| Class Action Plaintiffs
Commitments and Contingencies [Line Items]
Value of damages sought		$ 5
Number of plaintiffs \| claim	48	48
Lac-Megantic Rail Accident \| WD Trustee \| Damaged railcars and lost crude recovery
Commitments and Contingencies [Line Items]
Value of damages sought		$ 6
Lac-Megantic Rail Accident \| WD Trustee \| Reimbursement for settlement paid by consignor
Commitments and Contingencies [Line Items]
Value of damages sought		110
Lac-Megantic Rail Accident \| WD Trustee \| Reimbursement for settlement paid by consignee
Commitments and Contingencies [Line Items]
Value of damages sought		$ 60
Capital Expenditures
Commitments and Contingencies [Line Items]
Future committed expenditures	$ 664
Operating Expenditures
Commitments and Contingencies [Line Items]
Future committed expenditures	$ 3,100

Amount of fund to be distributed to those claiming derailment damages.

No definition available.

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- Definition

Long term purchase commitment period beginning year.

+ References

No definition available.

+ Details

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- Definition

Long term purchase commitment period ending year.

+ References

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- Definition

Loss Contingency, Damages Sought Previously, Value

+ References

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- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
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- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

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- Definition

Number of pending claims pertaining to a loss contingency.

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- Definition

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

+ References

No definition available.

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- Definition

Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

+ References

No definition available.

+ Details

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