XML 29 R91.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
FINANCIAL RISK MANAGEMENT AND FINANCIAL INSTRUMENTS - Credit Risk (Details) - Accounts receivable - CAD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Disclosure of financial assets that are either past due or impaired [line items]    
Financial assets $ 1,519 $ 1,474
Reconciliation of changes in allowance account for credit losses of financial assets [abstract]    
Balance, beginning of year 55 61
Allowance for doubtful accounts expense 238 201
Net use (233) (207)
Recoveries   17
Balance, end of year 60 55
Less than 30 days past billing date    
Disclosure of financial assets that are either past due or impaired [line items]    
Financial assets 1,053 970
30-60 days past billing date    
Disclosure of financial assets that are either past due or impaired [line items]    
Financial assets 274 300
61-90 days past billing date    
Disclosure of financial assets that are either past due or impaired [line items]    
Financial assets 90 100
Greater than 90 days past billing date    
Disclosure of financial assets that are either past due or impaired [line items]    
Financial assets 102 104
Gross carrying amount    
Disclosure of financial assets that are either past due or impaired [line items]    
Financial assets $ 464 $ 477