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Retirement Benefit Plans - Maturity Analysis of Undiscounted Benefit Payments (Detail) $ in Millions | 12 Months Ended
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Dec. 31, 2017 TWD ($)
Disclosure Of Defined Benefit Plans [Abstract] |
2018 | $ 2,042
2019 | 4,716
2020 | 8,088
2021 | 11,201
2022 and thereafter | 48,310
Total | $ 74,357

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- Definition Estimated future benefit payments. + References No definition available. + Details
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- Definition Estimated future benefit payments Five Fiscal Years Thereafter + References No definition available. + Details
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- Definition Estimated future benefit payments next twelve months + References No definition available. + Details
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- Definition Estimated future benefit payments Year Four + References No definition available. + Details
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- Definition Estimated future benefit payments Year Three + References No definition available. + Details
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- Definition Estimated future benefit payments Year Two + References No definition available. + Details
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