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Net Income (loss) per Common Share - Additional Information (Detail) - shares shares in Millions	3 Months Ended		9 Months Ended
	Oct. 01, 2017	Oct. 02, 2016	Oct. 01, 2017
Net Income Loss Per Common Share
Exercise of stock options	0.1	0.1	0.1

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- Definition

Net Income (Loss) Per Common Share [Line Items]

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No definition available.

+ Details

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- Definition

Stock Issued During Period Shares Sale Of Stock And Exercise Of Stock Options

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No definition available.

+ Details

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