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v3.19.1

Investments Accounted for Using the Equity Method - Summary of Investments in Associates Accounted for Using the Equity Method (Detail) $ in Thousands, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 USD ($) | Dec. 31, 2017 TWD ($) | Dec. 31, 2018 TWD ($)
Disclosure of associates and joint ventures [line items] |  |  |
Investments in associates | $ 298,328 | $ 48,267,237 | $ 9,131,814
Siliconware Precision Industries Co., Ltd. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Main Business | Engaged in assembly, testing and turnkey services of integrated circuits |  |
Operating Location | R.O.C. |  |
Percentages of ownership held by the Group |  | 33.29% |
Deca Technologies Inc. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Main Business | Holding company and the group engaged in manufacturing, development and marketing of wafer level packaging and interconnect technology |  |
Operating Location | British Cayman Islands |  |
Percentages of ownership held by the Group | 22.04% | 22.04% |
Hung Ching Development & Construction Co. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Main Business | Engaged in the development, construction and leasing of real estate properties |  |
Operating Location | R.O.C. |  |
Percentages of ownership held by the Group | 26.22% | 26.22% |
Hung Ching Kwan Co. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Main Business | Engaged in the leasing of real estate properties |  |
Operating Location | R.O.C. |  |
Percentages of ownership held by the Group | 27.31% | 27.31% |
Advanced Microelectronic Products Inc. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Main Business | Engaged in integrated circuit |  |
Operating Location | R.O.C. |  |
Percentages of ownership held by the Group | 38.76% | 38.76% |
ChipMos Technologies Inc [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Main Business | Engaged in the packaging and testing of semiconductors |  |
Operating Location | R.O.C. |  |
Percentages of ownership held by the Group | 20.47% |  |
Yann Yuan Investment Co., Ltd. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Main Business | Engaged in investing activities |  |
Operating Location | R.O.C. |  |
Percentages of ownership held by the Group | 32.21% |  |
Cost [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments in associates | $ 308,134 | $ 48,567,386 | 9,431,963
Cost [member] | Siliconware Precision Industries Co., Ltd. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments in associates |  | 45,210,371 |
Cost [member] | Deca Technologies Inc. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments in associates | 28,302 | 1,583,124 | 866,312
Cost [member] | Hung Ching Development & Construction Co. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments in associates | 35,780 | 1,248,711 | 1,095,233
Cost [member] | Hung Ching Kwan Co. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments in associates | 9,663 | 309,630 | 295,772
Cost [member] | Advanced Microelectronic Products Inc. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments in associates | 6,015 | 215,550 | 184,134
Cost [member] | ChipMos Technologies Inc [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments in associates | 138,451 |  | 4,237,982
Cost [member] | Yann Yuan Investment Co., Ltd. [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments in associates | 89,923 |  | 2,752,530
Deferred gain on transfer of land [member] |  |  |
Disclosure of associates and joint ventures [line items] |  |  |
Investments in associates | $ 9,806 | $ 300,149 | $ 300,149

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