Fair Value - Summary of significant unobservable inputs used in fair value measurement of assets (Detail) - PEN (S/)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Non-listed shares [member] \| Equity Method [Member]
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items]
Description of valuation processes used in fair value measurement, assets	According to price risk	According to price risk
Percentage of increase decrease in sensitivity analysis of input fair value	5.00%	5.00%
Increase decrease in sensitivity analysis of input to fair value	S/ 1,682,000	S/ 1,882,000
NAV [member] \| Private Equity Stocks [Member] \| Net Asset Value Method [Member]
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items]
Description of valuation processes used in fair value measurement, assets	Depends on each investment	Depends on each investment
Percentage of increase decrease in sensitivity analysis of input fair value	10.00%	10.00%
Increase decrease in sensitivity analysis of input to fair value	S/ 12,086,000	S/ 8,096,000
NAV [member] \| Private Equity Funds [Member] \| Net Asset Value Method [Member]
Disclosure of significant unobservable inputs used in fair value measurement of assets [line items]
Description of valuation processes used in fair value measurement, assets	Depends on each investment	Depends on each investment
Percentage of increase decrease in sensitivity analysis of input fair value	10.00%	10.00%
Increase decrease in sensitivity analysis of input to fair value	S/ 93,138,000	S/ 93,119,000

The description of the valuation processes used by the entity for the fair value measurement of assets (including, for example, how an entity decides its valuation policies and procedures and analyses changes in fair value measurements from period to period).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2025-01-01
-Paragraph 93
-Subparagraph g
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=13&code=ifrs-tx-2025-en-r&anchor=para_93_g&doctype=Standard
-URIDate 2025-03-27

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