Contingencies - Legal Proceedings (Details) - Lac-Megantic Rail Accident [Member] $ in Millions	6 Months Ended
Jun. 30, 2019 CAD ($) claim
Claimed damages as a result of derailment
Other Commitments [Line Items]
Amount of fund to be distributed	$ 440
Quebec Minister of Sustainable Development, Environment, Wildlife and Parks
Other Commitments [Line Items]
Value of damages sought	95
Quebec Attorney General
Other Commitments [Line Items]
Value of damages sought	315
Initial value of damages sought	409
Initial Insurer Claimants \| Subrogated insurance claim
Other Commitments [Line Items]
Value of damages sought	14
Initial value of damages sought	$ 16
Number of pending claims \| claim	8
Additional Insurer Claimants \| Subrogated insurance claim
Other Commitments [Line Items]
Value of damages sought	$ 3
Number of pending claims \| claim	2
Plaintiffs
Other Commitments [Line Items]
Value of damages sought	$ 5
Number of Plaintiffs \| claim	48
The WD Trustee
Other Commitments [Line Items]
Value of damages sought	$ 60
The WD Trustee \| Damaged rail cars loss recovery
Other Commitments [Line Items]
Value of damages sought	6
Montreal Maine and Atlantic Railway
Other Commitments [Line Items]
Value of damages sought	$ 110

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

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- Definition

Loss Contingency, Damages Sought Previously, Value

+ References

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

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Number of pending claims pertaining to a loss contingency.

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