The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

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

Share Based Compensation Plans - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019 CAD ($) shares Year Incentive_Plan	Dec. 31, 2018 CAD ($) shares Year $ / shares	Dec. 31, 2018 CAD ($) $ / shares	Dec. 31, 2017 CAD ($) Year $ / shares
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Number of cash-settled share based incentive plans \| Incentive_Plan	2
Option vesting period	3 years
Option expiration term	7 years
Weighted average fair value of share options granted	$ 1.54	$ 1.96	$ 1.96
Average risk-free interest rate	2.50%	2.00%
Average expected life \| Year	4	4
Expected forfeiture rate	5.00%	5.00%
Expected volatility	57.00%	56.00%
Stock-based compensation expense	$ (8,193,000)	$ (6,390,000)
Employee Stock Purchase Plan [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Eligible employees contribute	10.00%
Employees matching contribute percentage	20.00%
Compensation expense		1,000,000
Restricted Share Units (RSUs) [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Shares granted to eligible employees vest term	3 years
Stock-based compensation expense	$ (5,755,000)	(5,223,000)
Performance Share Units (PSUs) [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Shares granted to eligible employees vest term	3 years
Stock-based compensation expense	$ (1,583,000)	$ (398,000)
U.S. Share Options [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Options Outstanding, Exercised \| shares	0	66,000
Weighted average share price \| $ / shares			$ 4.02
Stock-based compensation expense	$ 2,000,000	$ 3,000,000
Executive Performance Share Units [Member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Weighted average share price \| $ / shares		$ 3.23		$ 4.29
Weighted average fair value of share options granted		$ 4.11	$ 4.11	$ 6.22
Average risk-free interest rate		2.30%		2.30%
Average expected life \| Year		3		3
Expected volatility		56.00%		59.00%
Stock-based compensation expense		$ 12,000,000		$ 6,000,000
Expected dividend yield		0.00%		0.00%