Quarterly Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Details of Quarterly Information (Unaudited)
Revenue	$ 326,897	$ 205,399	$ 183,148	$ 168,467	$ 212,494	$ 168,610	$ 148,696	$ 130,804	$ 883,911	$ 660,604	$ 616,778
Gross margin	153,542	102,383	89,891	87,343	106,642	81,060	69,652	61,961	433,159	319,315	288,926
Net income	$ 4,620	$ 22,082	$ 7,903	$ 16,359	$ 13,681	$ 19,512	$ 4,814	$ 3,932	$ 50,964	$ 41,939	$ 44,130
Diluted earnings per share (in dollars per share)	$ 0.16	$ 0.76	$ 0.27	$ 0.58	$ 0.49	$ 0.70	$ 0.17	$ 0.13	$ 1.77	$ 1.48	$ 1.47

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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