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Revenue - Summary of Changes in Contract Assets and Contract Liabilities (Detail) - TWD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Contract assets |  |  |
Net increase of customer contracts | $ 5,972 | $ 6,066 | $ 4,126
Reclassified to trade receivables | (5,681) | (6,405) | (7,532)
Significant changes of contract assets | 291 | (339) | (3,406)
Contract liabilities |  |  |
Net increase of customer contracts | 7 | 22 | 16
Recognized as revenues | (30) | (89) | (194)
Significant changes of contract liabilities | $ (23) | $ (67) | $ (178)

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- Definition Decrease in contract asset through reclassification to trade receivables. + References No definition available. + Details
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- Definition Decrease in contract liabilities revenue recognition. + References No definition available. + Details
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- Definition Increase in contract asset through increase in customer contracts. + References No definition available. + Details
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- Definition Increase in contract liabilities through increase in customer contracts. + References No definition available. + Details
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- Definition Significant changes of contract liabilities. + References No definition available. + Details
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- References No definition available. + Details
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- References No definition available. + Details
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