BALANCE FROM CONTRACTS WITH CUSTOMERS - Narrative (Details) - CAD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Disclosure of disaggregation of revenue from contracts with customers [line items] | ||
| Revenue that was included in contract liability balance | $ 802.9 | $ 740.0 |
| (Reversal of) revenue from performance obligations satisfied or partially satisfied in previous periods | 11.8 | $ 45.7 |
| Remaining performance obligations | $ 8,562.4 | |
| No later than 1 year | ||
| Disclosure of disaggregation of revenue from contracts with customers [line items] | ||
| Performance obligations recognition expectation (in percent) | 35.00% | |
| Later than one year | ||
| Disclosure of disaggregation of revenue from contracts with customers [line items] | ||
| Performance obligations recognition expectation (in percent) | 18.00% | |