advance billings and customer deposits - Contract liabilities (Details) - CAD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
|
| advance billings and customer deposits | ||||
| Contract liabilities at beginning of period | $ 814 | $ 788 | $ 811 | $ 780 |
| Revenue deferred in previous period and recognized in current period | 642 | 637 | 647 | 689 |
| Net additions arising from operations | 638 | 628 | 641 | 686 |
| Additions arising from business acquisitions | 1 | 1 | 6 | 3 |
| Contract liabilities at end of period | 811 | 780 | 811 | 780 |
| Current | 732 | 691 | 732 | 691 |
| Non-current | ||||
| Deferred revenues | 65 | 72 | 65 | 72 |
| Deferred customer activation and connection fees | $ 14 | $ 17 | $ 14 | $ 17 |