v3.19.2

financial instruments - Accounts receivable (Details) - Customer accounts receivable - CAD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | Jun. 30, 2019 | Dec. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2016
Credit risk |  |  |  |  |  |  |  |  |
Weighted average age of receivables |  |  | 27 days |  | 30 days |  |  |  |
Weighted average age of past-due receivables |  |  | 60 days |  | 56 days |  |  |  |
Receivable account balances | $ 1,243 |  | $ 1,210 |  | $ 1,210 | $ 1,243 | $ 1,210 |  |
Written off amounts charged to allowance for doubtful accounts still subject to enforcement |  |  |  |  |  | 403 | 353 |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | (1,210) |  |  |  |  |  |
Balance, end of period | (1,243) |  | (1,243) |  | (1,210) |  |  |  |
Less than 30 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | 922 |  | 749 |  | 749 | 922 | 749 |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | (749) |  |  |  |  |  |
Balance, end of period | (922) |  | (922) |  | (749) |  |  |  |
30-60 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | 216 |  | 344 |  | 344 | 216 | 344 |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | (344) |  |  |  |  |  |
Balance, end of period | (216) |  | (216) |  | (344) |  |  |  |
61-90 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | 53 |  | 72 |  | 72 | 53 | 72 |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | (72) |  |  |  |  |  |
Balance, end of period | (53) |  | (53) |  | (72) |  |  |  |
More than 90 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | 52 |  | 45 |  | 45 | 52 | 45 |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | (45) |  |  |  |  |  |
Balance, end of period | (52) |  | (52) |  | (45) |  |  |  |
Cost/Gross amount |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | 1,285 |  | 1,263 |  | 1,263 | 1,285 | 1,263 |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | (1,263) |  |  |  |  |  |
Balance, end of period | (1,285) |  | (1,285) |  | (1,263) |  |  |  |
Cost/Gross amount | Less than 30 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | 934 |  | 762 |  | 762 | 934 | 762 |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | (762) |  |  |  |  |  |
Balance, end of period | (934) |  | (934) |  | (762) |  |  |  |
Cost/Gross amount | 30-60 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | 224 |  | 354 |  | 354 | 224 | 354 |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | (354) |  |  |  |  |  |
Balance, end of period | (224) |  | (224) |  | (354) |  |  |  |
Cost/Gross amount | 61-90 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | 59 |  | 80 |  | 80 | 59 | 80 |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | (80) |  |  |  |  |  |
Balance, end of period | (59) |  | (59) |  | (80) |  |  |  |
Cost/Gross amount | More than 90 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | 68 |  | 67 |  | 67 | 68 | 67 |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | (67) |  |  |  |  |  |
Balance, end of period | (68) |  | (68) |  | (67) |  |  |  |
Allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | (42) | $ (43) | (53) | $ (53) | (53) | (42) | (53) | $ (47) | $ (43)
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  | 43 | 53 | 53 | 53 |  |  |  |
Additions (doubtful accounts expense) | 10 | 11 | 21 | 27 |  |  |  |  |
Accounts written off, net of recoveries | (11) | (13) | (33) | (27) |  |  |  |  |
Other |  | 1 | 1 | 3 |  |  |  |  |
Balance, end of period | 42 | $ 46 | 42 | $ 46 | 53 |  |  |  |
Allowance for doubtful accounts | Less than 30 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | (12) |  | (13) |  | (13) | (12) | (13) |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | 13 |  |  |  |  |  |
Balance, end of period | 12 |  | 12 |  | 13 |  |  |  |
Allowance for doubtful accounts | 30-60 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | (8) |  | (10) |  | (10) | (8) | (10) |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | 10 |  |  |  |  |  |
Balance, end of period | 8 |  | 8 |  | 10 |  |  |  |
Allowance for doubtful accounts | 61-90 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | (6) |  | (8) |  | (8) | (6) | (8) |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | 8 |  |  |  |  |  |
Balance, end of period | 6 |  | 6 |  | 8 |  |  |  |
Allowance for doubtful accounts | More than 90 days past billing date |  |  |  |  |  |  |  |  |
Credit risk |  |  |  |  |  |  |  |  |
Receivable account balances | (16) |  | (22) |  | (22) | $ (16) | $ (22) |  |
Summary of activity related to allowance for doubtful accounts |  |  |  |  |  |  |  |  |
Balance, beginning of period |  |  | 22 |  |  |  |  |  |
Balance, end of period | $ 16 |  | $ 16 |  | $ 22 |  |  |  |

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