Insurance - Summary of Net Premiums and Claims (Detail) - CAD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Oct. 31, 2022 |
Oct. 31, 2021 |
|
| Gross amount [member] | ||
| Disclosure of net, gross and reinsurer's share for amounts arising from insurance contracts [line items] | ||
| Premiums | $ 4,913 | $ 5,090 |
| Claims and benefits | 1,741 | 3,834 |
| Reinsurers' share of amount [member] | ||
| Disclosure of net, gross and reinsurer's share for amounts arising from insurance contracts [line items] | ||
| Premiums | (260) | (250) |
| Claims and benefits | (273) | (287) |
| Net Amounts [member] | ||
| Disclosure of net, gross and reinsurer's share for amounts arising from insurance contracts [line items] | ||
| Premiums | 4,653 | 4,840 |
| Claims and benefits | $ 1,468 | $ 3,547 |