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Lease Arrangements - Summary of Range of Discount Rate for Lease Liabilities (Details) - Discount Rate [Member] - Lease Liabilities [Member] | Dec. 31, 2019
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Bottom of Range [Member] | Handsets Base Stations [Member] |
Disclosure Of Quantitative Information About Rightofuse Assets [Line Items] |
Range of discount rate | 0.58
Bottom of Range [Member] | Others [Member] |
Disclosure Of Quantitative Information About Rightofuse Assets [Line Items] |
Range of discount rate | 0.58
Bottom of Range [Member] | Equipment [Member] |
Disclosure Of Quantitative Information About Rightofuse Assets [Line Items] |
Range of discount rate | 0.58
Top of Range [Member] | Handsets Base Stations [Member] |
Disclosure Of Quantitative Information About Rightofuse Assets [Line Items] |
Range of discount rate | 1.18
Top of Range [Member] | Others [Member] |
Disclosure Of Quantitative Information About Rightofuse Assets [Line Items] |
Range of discount rate | 9.00
Top of Range [Member] | Equipment [Member] |
Disclosure Of Quantitative Information About Rightofuse Assets [Line Items] |
Range of discount rate | 4.50

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- Definition The value of significant unobservable input used in the measurement of the fair value of assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2019-01-01 -Paragraph 93 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=13&code=ifrs-tx-2019-en-r&anchor=para_93_d&doctype=Standard -URIDate 2019-03-27 + Details
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