Share Capital - Share-based Payment Transactions - Additional Information (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2019 CAD ($) yr	Dec. 31, 2018 CAD ($) yr
Disclosure of range of exercise prices of outstanding share options [line items]
Share options, Granted	0	1,112,779
Fair value of options granted	The fair value of options granted was determined at the date of grant using the Black-Scholes option-pricing model.
Estimated fair value of options granted on the grant date		$ 5,730
Expected hold period to exercise (years) \| yr		3.50
Outstanding fair value	$ 23,000	$ 12,800
Performance share units (PSUs) [member]
Disclosure of range of exercise prices of outstanding share options [line items]
Number of shares issued	379,289	280,884
Outstanding fair value	$ 11,100	$ 3,600
Weighted average exercise price of other equity instruments granted in share-based payment arrangement	$ 11,600	$ 8,900
Performance share units (PSUs) [member] \| Bottom of range [member]
Disclosure of range of exercise prices of outstanding share options [line items]
Number of units vest percentage	0.00%
Share Based Payment Arrangement Equity Instrument Other than Opion Granted Percent Incerase	40.00%
Performance share units (PSUs) [member] \| Top of range [member]
Disclosure of range of exercise prices of outstanding share options [line items]
Number of units vest percentage	200.00%
Share Based Payment Arrangement Equity Instrument Other than Opion Granted Percent Incerase	60.00%
Deferred share unit [member]
Disclosure of range of exercise prices of outstanding share options [line items]
Number of shares issued	44,806	46,356
Vested fair value	$ 10,200	$ 9,000
Weighted average exercise price of other equity instruments granted in share-based payment arrangement	$ 1,200	1,400
Restricted Stock Units [Member]
Disclosure of range of exercise prices of outstanding share options [line items]
Number of shares issued	166,963
Outstanding fair value	$ 1,100	$ 0
Estimated historical data [member]
Disclosure of range of exercise prices of outstanding share options [line items]
Expected hold period to exercise (years) \| yr	5
Officers and employees [member]
Disclosure of range of exercise prices of outstanding share options [line items]
Share options, Granted		1,112,779
Officers and employees [member] \| Restricted Stock Units [Member]
Disclosure of range of exercise prices of outstanding share options [line items]
Number of shares issued	164,719
Weighted average exercise price of other equity instruments granted in share-based payment arrangement	$ 5,300

The option life of share options granted.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2019-01-01
-Paragraph 47
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2019-en-r&anchor=para_47_a_i&doctype=Standard
-URIDate 2019-03-27

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The intrinsic value of liabilities arising from share-based transactions for which the counterparty's right to cash or other assets had vested by the end of the period (for example, vested share appreciation rights). The intrinsic value is the difference between the fair value of the shares to which the counterparty has the (conditional or unconditional) right to subscribe, or which it has the right to receive, and the price (if any) that the counterparty is (or will be) required to pay for those shares. Share-based payment transactions are transactions in which the entity: (a) receives goods or services from the supplier of those goods or services (including an employee) in a share-based payment arrangement; or (b) incurs an obligation to settle the transaction with the supplier in a share-based payment arrangement when another group entity receives those goods or services, for which the counterparty's right to cash or other assets had vested by the end of the period (for example, vested share appreciation rights).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2019-01-01
-Paragraph 51
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The amount of liabilities arising from share-based payment transactions. Share-based payment transactions are transactions in which the entity: (a) receives goods or services from the supplier of those goods or services (including an employee) in a share-based payment arrangement; or (b) incurs an obligation to settle the transaction with the supplier in a share-based payment arrangement when another group entity receives those goods or services. [Refer: Share-based payment arrangements [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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The number of share options granted in a share-based payment arrangement.

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The weighted average fair value of share options granted during the period at the measurement date. [Refer: Weighted average [member]]

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Share-based payment arrangement vesting rights percentage.

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