Net Income Per Share (Details) - HKD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Basic and diluted income per share      
Net income/(loss) for the year attributable to the Company’s ordinary shareholders - Numerator $ 139,895 $ 692,042 $ 131,335
Net income/(loss) for the year attributable to the Company’s ordinary shareholders - Continuing operations (1,446) 5,508 (1,917)
Net income/(loss) for the year attributable to the Company’s ordinary shareholders - Discontinued operations $ 141,341 $ 686,534 $ 133,252
Weighted average number of basic and diluted ordinary shares outstanding - Continuing operations 12,938,128 12,938,128 12,938,128
Weighted average number of basic and diluted ordinary shares outstanding - Discontinued operations 12,938,128 12,938,128 12,938,128
Net income of Basic and diluted income per share $ 10.81 $ 53.50 $ 10.20
Net income of Basic and diluted income per share - Continuing operations (0.11) 0.44 (0.15)
Net income of Basic and diluted income per share - Discontinued operations $ 10.92 $ 53.06 $ 10.35