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Summary of Significant Accounting Policies - Additional information (Detail) - Chunghwa Investment Co., Ltd. ("CHI") [Member] | Dec. 31, 2020
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CHIEF Telecom Inc. ("CHIEF") [Member] |
Disclosure of subsidiaries [Line Items] |
Percentage of Ownership interests | 2.95%
Senao International Co., Ltd. (SENAO) [Member] |
Disclosure of subsidiaries [Line Items] |
Percentage of Ownership interests | 0.39%

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- Definition Percentage of ownership interest in subsidiary. + References No definition available. + Details
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Details
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- Details
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