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v3.21.1

Property, Plant and Equipment, Net - Summary of Property, Plant and Equipment, Net (Detail) $ in Thousands, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 TWD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 TWD ($) | Dec. 31, 2018 TWD ($)
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | $ 17,979,444 |  | $ 16,819,621 | $ 15,265,311
Effects on initial application of IFRS 16 |  |  | (31,904) |
Adjusted Balance On Property Plant And Equipment |  |  | 16,787,717 |
Additions | 4,133,615 |  | 4,896,656 | 4,945,570
Disposals | (19,358) |  | (25,785) | (14,716)
Reclassifications | 0 |  | 26,618 | 0
Depreciation expenses | (4,098,993) |  | (3,695,815) | (3,376,579)
Impairment losses |  |  | (9,938) |
Exchange adjustments | (22) |  | (9) | 35
Ending Balance | 17,994,686 | $ 640,836 | 17,979,444 | 16,819,621
Land [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 452,738 |  | 452,738 | 452,738
Adjusted Balance On Property Plant And Equipment |  |  | 452,738 |
Additions | 0 |  | 0 | 0
Disposals | 0 |  | 0 | 0
Reclassifications | 0 |  | 0 | 0
Depreciation expenses | 0 |  | 0 | 0
Ending Balance | 452,738 |  | 452,738 | 452,738
Buildings [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 4,095,929 |  | 3,908,731 | 3,919,086
Adjusted Balance On Property Plant And Equipment |  |  | 3,908,731 |
Additions | 132,572 |  | 116,238 | 247,186
Disposals | 0 |  | 0 | 0
Reclassifications | 258,421 |  | 455,792 | 199,724
Depreciation expenses | (394,636) |  | (384,832) | (457,265)
Ending Balance | 4,092,286 |  | 4,095,929 | 3,908,731
Machinery and equipment [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 11,163,121 |  | 10,232,093 | 8,813,727
Adjusted Balance On Property Plant And Equipment |  |  | 10,232,093 |
Additions | 592,565 |  | 2,334,358 | 2,445,313
Disposals | (8,940) |  | (16,033) | (904)
Reclassifications | 2,336,238 |  | 1,111,715 | 1,154,663
Depreciation expenses | (2,734,667) |  | (2,489,070) | (2,180,718)
Impairment losses |  |  | (9,938) |
Exchange adjustments | (20) |  | (4) | 12
Ending Balance | 11,348,297 |  | 11,163,121 | 10,232,093
Tools [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 896,476 |  | 742,179 | 690,469
Adjusted Balance On Property Plant And Equipment |  |  | 742,179 |
Additions | 409,832 |  | 781,465 | 591,229
Disposals | (3,121) |  | (9,336) | (11,745)
Reclassifications | 398,798 |  | 7,880 | 7,604
Depreciation expenses | (749,624) |  | (625,712) | (535,378)
Ending Balance | 952,361 |  | 896,476 | 742,179
Other equipment [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 434,791 |  | 413,988 | 420,572
Effects on initial application of IFRS 16 |  |  | (31,904) |
Adjusted Balance On Property Plant And Equipment |  |  | 382,084 |
Additions | 142,776 |  | 224,287 | 172,652
Disposals | (7,297) |  | (416) | (2,067)
Reclassifications | 159,195 |  | 25,042 | 26,026
Depreciation expenses | (220,066) |  | (196,201) | (203,218)
Exchange adjustments | (2) |  | (5) | 23
Ending Balance | 509,397 |  | 434,791 | 413,988
Construction in progress and equipment to be inspected [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 936,389 |  | 1,069,892 | 968,719
Adjusted Balance On Property Plant And Equipment |  |  | 1,069,892 |
Additions | 2,855,870 |  | 1,440,308 | 1,489,190
Disposals | 0 |  | 0 | 0
Reclassifications | (3,152,652) |  | (1,573,811) | (1,388,017)
Depreciation expenses | 0 |  | 0 | 0
Ending Balance | 639,607 |  | 936,389 | 1,069,892
Gross carrying amount [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 70,401,687 |  | 67,064,936 | 63,638,420
Ending Balance | 73,187,794 |  | 70,401,687 | 67,064,936
Gross carrying amount [member] | Land [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 452,738 |  | 452,738 | 452,738
Ending Balance | 452,738 |  | 452,738 | 452,738
Gross carrying amount [member] | Buildings [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 10,821,972 |  | 10,254,531 | 9,809,970
Ending Balance | 11,212,129 |  | 10,821,972 | 10,254,531
Gross carrying amount [member] | Machinery and equipment [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 51,244,512 |  | 48,274,171 | 45,778,207
Ending Balance | 53,246,474 |  | 51,244,512 | 48,274,171
Gross carrying amount [member] | Tools [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 5,008,321 |  | 4,402,711 | 4,004,703
Ending Balance | 5,451,547 |  | 5,008,321 | 4,402,711
Gross carrying amount [member] | Other equipment [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 1,937,755 |  | 2,610,893 | 2,624,083
Ending Balance | 2,185,299 |  | 1,937,755 | 2,610,893
Gross carrying amount [member] | Construction in progress and equipment to be inspected [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 936,389 |  | 1,069,892 | 968,719
Ending Balance | 639,607 |  | 936,389 | 1,069,892
Accumulated depreciation and impairment [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | (52,422,243) |  | (50,245,315) | (48,373,109)
Ending Balance | (55,193,108) |  | (52,422,243) | (50,245,315)
Accumulated depreciation and impairment [member] | Land [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 0 |  | 0 | 0
Ending Balance | 0 |  | 0 | 0
Accumulated depreciation and impairment [member] | Buildings [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | (6,726,043) |  | (6,345,800) | (5,890,884)
Ending Balance | (7,119,843) |  | (6,726,043) | (6,345,800)
Accumulated depreciation and impairment [member] | Machinery and equipment [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | (40,081,391) |  | (38,042,078) | (36,964,480)
Ending Balance | (41,898,177) |  | (40,081,391) | (38,042,078)
Accumulated depreciation and impairment [member] | Tools [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | (4,111,845) |  | (3,660,532) | (3,314,234)
Ending Balance | (4,499,186) |  | (4,111,845) | (3,660,532)
Accumulated depreciation and impairment [member] | Other equipment [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | (1,502,964) |  | (2,196,905) | (2,203,511)
Ending Balance | (1,675,902) |  | (1,502,964) | (2,196,905)
Accumulated depreciation and impairment [member] | Construction in progress and equipment to be inspected [member] |  |  |  |
Disclosure of detailed information about property, plant and equipment [Line Items] |  |  |  |
Beginning Balance | 0 |  | 0 | 0
Ending Balance | $ 0 |  | $ 0 | $ 0

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- Definition The amount of additions to property, plant and equipment other than those acquired through business combinations. [Refer: Business combinations [member]; Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2020-01-01 -Paragraph 73 -Subparagraph e -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2020-en-r&anchor=para_73_e_i&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The increase (decrease) in property, plant and equipment resulting from net exchange differences arising on the translation of the financial statements from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2020-01-01 -Paragraph 73 -Subparagraph e -Clause viii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2020-en-r&anchor=para_73_e_viii&doctype=Standard -URIDate 2020-01-01 + Details
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