Net Income Per Share (Details 1) - shares shares in Thousands	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Potential shares of Cadence's common stock excluded
Total potential common shares excluded	977	532	1,677
Long-term performance-based awards
Potential shares of Cadence's common stock excluded
Total potential common shares excluded	50	152	1,069
Options to purchase shares of common stock
Potential shares of Cadence's common stock excluded
Total potential common shares excluded	637	303	581
Non-vested shares of restricted stock
Potential shares of Cadence's common stock excluded
Total potential common shares excluded	290	77	27