Leases - Additional Information (Details) - CAD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Leases
Total cash outflow	$ 33,276	$ 27,468
Interest on lease liabilities	$ 6,984	$ 7,185

The amount of interest expense on lease liabilities. [Refer: Lease liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2019-01-01
-Paragraph 53
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_b&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_InterestExpenseOnLeaseLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration