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Revenue - Summary of Contract Balances (Detail) $ in Millions, $ in Millions | Dec. 31, 2018 TWD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 TWD ($)
--- | --- | --- | ---
Disclosure Of Contract Balance [Abstract] |  |  |
Trade notes and accounts receivable, net | $ 30,076 | $ 983 | $ 31,941
Contract assets |  |  |
Products and service bundling | 7,123 |  |
Other | 109 |  |
Less : Loss allowance | (19) |  |
Contract assets | 7,213 |  |
Contract assets | 4,869 | 159 | 0
Contract assets | 2,344 | 77 | 0
Contract liabilities |  |  |
Telecommunications business | 8,193 |  |
Project business | 4,508 |  |
Products and service bundling | 106 |  |
Other | 476 |  |
Contract liabilities | 13,283 |  |
Current Contract Liabilities | 10,688 | 349 | 0
Noncurrent Contract Liabilities | 2,595 | $ 85 | $ 0
Contract liabilities | $ 13,283 |  |

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- Definition The amount of an entity’s right to consideration in exchange for goods or services that the entity has transferred to a customer, when that right is conditioned on something other than the passage of time (for example, the entity’s future performance). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2018-01-01 -Paragraph 105 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=15&date=2018-03-01&anchor=para_105&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2018-01-01 -Paragraph 116 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=15&date=2018-03-01&anchor=para_116_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of an entity’s obligation to transfer goods or services to a customer for which the entity has received consideration (or the amount is due) from the customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2018-01-01 -Paragraph 105 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=15&date=2018-03-01&anchor=para_105&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2018-01-01 -Paragraph 116 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=15&date=2018-03-01&anchor=para_116_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of current contract assets. [Refer: Contract assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2018-01-01 -Paragraph 105 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=15&date=2018-03-01&anchor=para_105&doctype=Standard -URIDate 2018-03-16 + Details
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