Share-Based Compensation - Summary of Share Option Granted, Exercise Price, Fair Value, Intrinsic Value (Detail) - $ / shares						9 Months Ended
	Nov. 04, 2015	Oct. 31, 2015	Sep. 02, 2015	Aug. 05, 2015	May. 20, 2015	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Options Granted	11,400	39,727	25,000	8,000	312,300	396,427
Exercise Price						$ 14.86
Ordinary Shares Fair Value Per Share at Grant Date	$ 13.00	$ 11.62	$ 16.34	$ 16.70	$ 15.17
May 20, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grant Date						May 20, 2015
Number of Options Granted						312,300
Exercise Price						$ 15.17
Ordinary Shares Fair Value Per Share at Grant Date						15.17
Per Share Intrinsic Value of Options						$ 6.08
August 5, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grant Date						Aug. 05, 2015
Number of Options Granted						8,000
Exercise Price						$ 16.70
Ordinary Shares Fair Value Per Share at Grant Date						16.70
Per Share Intrinsic Value of Options						$ 6.54
September 2, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grant Date						Sep. 02, 2015
Number of Options Granted						25,000
Exercise Price						$ 16.34
Ordinary Shares Fair Value Per Share at Grant Date						16.34
Per Share Intrinsic Value of Options						$ 6.52
October 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grant Date						Oct. 31, 2015
Number of Options Granted						39,727
Exercise Price						$ 11.62
Ordinary Shares Fair Value Per Share at Grant Date						11.62
Per Share Intrinsic Value of Options						$ 4.76
November 4, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grant Date						Nov. 04, 2015
Number of Options Granted						11,400
Exercise Price						$ 13.00
Ordinary Shares Fair Value Per Share at Grant Date						13.00
Per Share Intrinsic Value of Options						$ 5.33