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Capital surplus and retained earnings (Tables) | 12 Months Ended
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Dec. 31, 2019
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Summary of Capital Surplus | Details of the Group’s capital surplus are set out below:
|  | 2017 |
|  | Share premium |  |  | Employee restricted shares |  |  | Others |  |  | Total |
|  | NT$000 |  |  | NT$000 |  |  | NT$000 |  |  | NT$000 |
January 1 |  |  | 6,473,471 |  |  |  | 408,051 |  |  |  | 7,304 |  |  |  | 6,888,826 |
Share-based payments |  |  | — |  |  |  | (17,650 | ) |  |  | — |  |  |  | (17,650 | )
Cash distribution from capital surplus |  |  | (599,728 | ) |  |  | — |  |  |  | — |  |  |  | (599,728 | )
December 31 |  |  | 5,873,743 |  |  |  | 390,401 |  |  |  | 7,304 |  |  |  | 6,271,448 |
|  | 2018 |
|  | Share premium |  |  | Employee restricted shares |  |  | Others |  |  | Total |
|  | NT$000 |  |  | NT$000 |  |  | NT$000 |  |  | NT$000 |
January 1 |  |  | 5,873,743 |  |  |  | 390,401 |  |  |  | 7,304 |  |  |  | 6,271,448 |
Share-based payments |  |  | — |  |  |  | (7,967 | ) |  |  | — |  |  |  | (7,967 | )
Capital reduction |  |  | — |  |  |  | 72 |  |  |  | — |  |  |  | 72 |
December 31 |  |  | 5,873,743 |  |  |  | 382,506 |  |  |  | 7,304 |  |  |  | 6,263,553 |
|  | 2019 |
|  | Share premium |  |  | Employee restricted shares |  |  | Others |  |  | Total |
|  | NT$000 |  |  | NT$000 |  |  | NT$000 |  |  | NT$000 |
January 1 |  |  | 5,873,743 |  |  |  | 382,506 |  |  |  | 7,304 |  |  |  | 6,263,553 |
Share-based payments |  |  | — |  |  |  | (412 | ) |  |  | — |  |  |  | (412 | )
Cancellation of treasury stock |  |  | (199,501 | ) |  |  | (12,853 | ) |  |  | — |  |  |  | (212,354 | )
December 31 |  |  | 5,674,242 |  |  |  | 369,241 |  |  |  | 7,304 |  |  |  | 6,050,787 |
Summary of Distribution Towards Legal Reserve and Cash Dividend | The appropriations of 2016, 2017 and 2018 were resolved at the shareholders’ meetings on May 26, 2017, June 26, 2018 and June 10, 2019, respectively. Details are summarized below:
|  | 2016 |  |  | 2017 |  |  | 2018 |
|  | Amount |  |  | Cash Distribution per share |  |  | Amount |  |  | Cash Distribution per share |  |  | Amount |  |  | Cash Distribution per share |
|  | NT$000 |  |  | NT$ |  |  | NT$000 |  |  | NT$ |  |  | NT$000 |  |  | NT$ |
Legal reserve |  |  | 28,680 |  |  |  |  |  |  |  | 302,653 |  |  |  |  |  |  |  | 110,308 |  |  |  |  |
Cash dividend |  |  | 257,026 |  |  |  | 0.30 |  |  |  | 256,806 |  |  |  | 0.30 |  |  |  | 872,718 |  |  |  | 1.20 |
Cash distribution from capital surplus |  |  | 599,728 |  |  |  | 0.70 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |

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- Definition Components capital surplus. + References No definition available. + Details
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- Definition Distribution towards legal reserve and cash dividend. + References No definition available. + Details
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