Contents of Significant Accounts - Operating Revenues - Additional Information (Detail) - TWD ($) $ in Millions |
12 Months Ended | |
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Dec. 31, 2025 |
Dec. 31, 2024 |
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| Disclosure of additional information about revenue [Abstract] | ||
| Revenue that was included in contract liability balance at beginning of period | $ 1,790 | $ 3,416 |
| Transaction price allocated to unsatisfied performance obligations | 288 | 355 |
| Asset recognized from the cost to fulfill a contract with customer | $ 1,186 | $ 584 |
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- Definition The amount of assets recognised from the costs to obtain or fulfil contracts with customers. The costs to obtain a contract with a customer are the incremental costs of obtaining the contract that the entity would not have incurred if the contract had not been obtained. The costs to fulfil a contract with a customer are the costs that relate directly to a contract or to an anticipated contract that the entity can specifically identify. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of the transaction price allocated to the performance obligations that are unsatisfied (or partially unsatisfied) as of the end of the reporting period. The transaction price is the amount of consideration to which an entity expects to be entitled in exchange for transferring promised goods or services to a customer, excluding amounts collected on behalf of third parties (for example, some sales taxes). [Refer: Performance obligations [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Disclosure of additional information about revenue. No definition available.
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