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Derivative Instruments - Schedule of Fair Value of Derivative Instruments (Detail) - CAD ($) $ in Millions | Oct. 31, 2025 | Oct. 31, 2024
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Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total |  | $ (58,729) | $ (58,303)
Total fair value - trading and hedging derivatives |  | (1,578) | (11,050)
Total |  | (1,578) | (11,050)
Trading Derivatives [Member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total fair value - trading derivatives |  | (2,941) | (11,834)
Trading Derivatives [Member] | Interest rate contracts [member] | Swap contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | (2,824) | (2,504)
Trading Derivatives [Member] | Interest rate contracts [member] | Forward rate agreements [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | (59) | 196
Trading Derivatives [Member] | Interest rate contracts [member] | Purchased options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | 2,783 | 2,574
Trading Derivatives [Member] | Interest rate contracts [member] | Written options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | (2,639) | (2,341)
Trading Derivatives [Member] | Interest rate contracts [member] | Futures contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | (6) | 11
Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Purchased options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | 1,534 | 657
Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Written options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | (1,362) | (528)
Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Forward Exchange Contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | 3,077 | 2,054
Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Cross currency swaps [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | 2,485 | 611
Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Cross currency interest rate contracts [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | (1,271) | (1,090)
Trading Derivatives [Member] | Commodity contract [member] | Swap contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Commodity contracts |  | (78) | (74)
Trading Derivatives [Member] | Commodity contract [member] | Purchased options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Commodity contracts |  | 257 | 644
Trading Derivatives [Member] | Commodity contract [member] | Written options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Commodity contracts |  | (304) | (607)
Trading Derivatives [Member] | Commodity contract [member] | Futures contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Commodity contracts |  | (21) | 43
Trading Derivatives [Member] | Equity contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Equity contracts |  | (4,514) | (11,479)
Trading Derivatives [Member] | Credit Contracts [member] | Purchased options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Credit Contracts |  |  | (9)
Trading Derivatives [Member] | Credit Contracts [member] | Written options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Credit Contracts |  | 1 | 8
Hedging Derivatives [Member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total fair value - hedging derivatives | [2] | 1,363 | 784
Hedging Derivatives [Member] | Interest rate contracts [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Cash flow hedges - swaps | [3] | 2,467 | 1,233
Fair value hedges - swaps | [3] | (1,140) | (125)
Total swaps | [3] | 1,327 | 1,108
Hedging Derivatives [Member] | Foreign Exchange Contracts [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Fair value hedges |  |  | (2)
Cash flow hedges |  | 23 | (381)
Net investment hedges |  | (16) | (4)
Total foreign exchange contracts |  | 7 | (387)
Hedging Derivatives [Member] | Equity contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Equity contracts |  | 29 | 63
Hedging Derivatives [Member] | Equity contract [member] | Cash flow hedges [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Equity contracts |  | 29 | 63
Gross assets [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Less: impact of master netting agreements |  | 43,254 | 31,576
Total |  | 13,897 | 15,677
Gross assets [member] | Fair value trading and hedging derivatives assets [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total fair value - trading and hedging derivatives |  | 57,151 | 47,253
Gross assets [member] | Trading Derivatives [Member] | Interest rate contracts [member] | Swap contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | 2,081 | 3,203
Gross assets [member] | Trading Derivatives [Member] | Interest rate contracts [member] | Forward rate agreements [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | 96 | 477
Gross assets [member] | Trading Derivatives [Member] | Interest rate contracts [member] | Purchased options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | 2,783 | 2,574
Gross assets [member] | Trading Derivatives [Member] | Interest rate contracts [member] | Futures contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | 4 | 21
Gross assets [member] | Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Purchased options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | 1,534 | 657
Gross assets [member] | Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Forward Exchange Contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | 13,535 | 8,150
Gross assets [member] | Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Cross currency swaps [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | 2,796 | 1,989
Gross assets [member] | Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Cross currency interest rate contracts [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | 11,078 | 9,777
Gross assets [member] | Trading Derivatives [Member] | Commodity contract [member] | Swap contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Commodity contracts |  | 1,004 | 1,023
Gross assets [member] | Trading Derivatives [Member] | Commodity contract [member] | Purchased options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Commodity contracts |  | 257 | 644
Gross assets [member] | Trading Derivatives [Member] | Commodity contract [member] | Futures contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Commodity contracts |  | 201 | 160
Gross assets [member] | Trading Derivatives [Member] | Equity contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Equity contracts |  | 16,459 | 14,194
Gross assets [member] | Trading Derivatives [Member] | Fair value trading derivatives assets [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total fair value - trading derivatives |  | 51,829 | 42,879
Gross assets [member] | Trading Derivatives [Member] | Credit Contracts [member] | Purchased options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Credit Contracts |  |  | 1
Gross assets [member] | Trading Derivatives [Member] | Credit Contracts [member] | Written options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Credit Contracts |  | 1 | 9
Gross assets [member] | Hedging Derivatives [Member] | Interest rate contracts [member] | Cash flow hedge in swaps asset [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts | [3] | 2,931 | 2,148
Gross assets [member] | Hedging Derivatives [Member] | Interest rate contracts [member] | Fair value hedge in swaps asset [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts | [3] | 786 | 1,464
Gross assets [member] | Hedging Derivatives [Member] | Interest rate contracts [member] | Assets swaps [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total swaps | [3] | 3,717 | 3,612
Gross assets [member] | Hedging Derivatives [Member] | Foreign Exchange Contracts [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts |  | 1,576 | 699
Total foreign exchange contracts |  | 1,576 | 699
Gross assets [member] | Hedging Derivatives [Member] | Equity contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Equity contracts |  | 29 | 63
Gross assets [member] | Hedging Derivatives [Member] | Equity contract [member] | Cash flow hedges [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Equity contracts |  | 29 | 63
Gross assets [member] | Hedging Derivatives [Member] | Fair value hedging derivatives assets [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total fair value - hedging derivatives | [2] | 5,322 | 4,374
Gross Liabilities [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Less: impact of master netting agreements |  | 43,254 | 31,576
Total |  | (15,475) | (26,727)
Gross Liabilities [member] | Fair value trading and hedging derivatives liabilities [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total |  | 58,729 | (58,303)
Gross Liabilities [member] | Trading Derivatives [Member] | Interest rate contracts [member] | Swap contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | (4,905) | (5,707)
Gross Liabilities [member] | Trading Derivatives [Member] | Interest rate contracts [member] | Forward rate agreements [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | (155) | (281)
Gross Liabilities [member] | Trading Derivatives [Member] | Interest rate contracts [member] | Written options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | (2,639) | (2,341)
Gross Liabilities [member] | Trading Derivatives [Member] | Interest rate contracts [member] | Futures contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts |  | (10) | (10)
Gross Liabilities [member] | Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Written options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | (1,362) | (528)
Gross Liabilities [member] | Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Forward Exchange Contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | (10,458) | (6,096)
Gross Liabilities [member] | Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Cross currency swaps [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | (311) | (1,378)
Gross Liabilities [member] | Trading Derivatives [Member] | Foreign Exchange Contracts [member] | Cross currency interest rate contracts [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Foreign exchange contracts | [1] | (12,349) | (10,867)
Gross Liabilities [member] | Trading Derivatives [Member] | Commodity contract [member] | Swap contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Commodity contracts |  | (1,082) | (1,097)
Gross Liabilities [member] | Trading Derivatives [Member] | Commodity contract [member] | Written options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Commodity contracts |  | (304) | (607)
Gross Liabilities [member] | Trading Derivatives [Member] | Commodity contract [member] | Futures contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Commodity contracts |  | (222) | (117)
Gross Liabilities [member] | Trading Derivatives [Member] | Equity contract [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Equity contracts |  | (20,973) | (25,673)
Gross Liabilities [member] | Trading Derivatives [Member] | Fair value trading derivatives liabilities [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total fair value - trading derivatives |  | (54,770) | (54,713)
Gross Liabilities [member] | Trading Derivatives [Member] | Credit Contracts [member] | Purchased options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Credit Contracts |  |  | (10)
Gross Liabilities [member] | Trading Derivatives [Member] | Credit Contracts [member] | Written options [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Credit Contracts |  |  | (1)
Gross Liabilities [member] | Hedging Derivatives [Member] | Interest rate contracts [member] | Cash flow hedge in swaps liabilities [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts | [3] | (464) | (915)
Gross Liabilities [member] | Hedging Derivatives [Member] | Interest rate contracts [member] | Fair value hedge in swaps liabilities [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Interest rate contracts | [3] | (1,926) | (1,589)
Gross Liabilities [member] | Hedging Derivatives [Member] | Interest rate contracts [member] | Liabilities swaps [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total swaps | [3] | (2,390) | (2,504)
Gross Liabilities [member] | Hedging Derivatives [Member] | Foreign Exchange Contracts [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Cash flow hedges |  | (1,553) | (1,080)
Fair value hedges |  |  | (2)
Total foreign exchange contracts |  | (1,569) | (1,086)
Net investment hedges |  | (16) | (4)
Gross Liabilities [member] | Hedging Derivatives [Member] | Fair value hedging derivatives liabilities [member] |  |  |
Disclosure Of Derivative Financial Instruments [Line Items] |  |  |
Total fair value - hedging derivatives | [2] | $ (3,959) | $ (3,590)
[1] | Gold contracts are included in foreign exchange contracts.
[2] | The fair values of hedging derivatives wholly or partially offset the changes in fair values of the related on-balance sheet financial instruments.
[3] | Includes the fair value of bond futures in fair value hedges rounded down to $nil million as at October 31, 2025 ($nil million as at October 31, 2024).

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- Definition The amounts that are subject to an enforceable master netting arrangement or similar agreement and that are not set off against financial assets. [Refer: Financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2024-01-01 -Paragraph 13C -Subparagraph d -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_13C_d&doctype=Standard -URIDate 2024-03-27 + Details
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- Definition The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2024-01-01 -Paragraph 55 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_55&doctype=Standard -URIDate 2024-03-27 + Details
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