Net Income Per Share (Details 1) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Potential shares of Cadence's common stock excluded
Total potential common shares excluded	704	112	1,023	652
Long-term performance-based stock awards
Potential shares of Cadence's common stock excluded
Total potential common shares excluded	0	100	50	186
Options to purchase shares of common stock
Potential shares of Cadence's common stock excluded
Total potential common shares excluded	701	0	606	404
Non-vested shares of restricted stock
Potential shares of Cadence's common stock excluded
Total potential common shares excluded	3	12	367	62