Stock Compensation Plans and Stock Based Compensation (Details 10) shares in Thousands	Dec. 28, 2019 shares
Common stock reserved for future issuance
Common stock reserved for future issuance	22,842
Employee equity incentive plans [Member]
Common stock reserved for future issuance
Common stock reserved for future issuance	15,898	[1]
Employee stock purchase plans [Member]
Common stock reserved for future issuance
Common stock reserved for future issuance	6,039
Directors stock option plans [Member]
Common stock reserved for future issuance
Common stock reserved for future issuance	905	[1]

[1] Includes shares reserved for: (i) issuance upon exercise of future option grants, (ii) issuance upon vesting of future restricted stock grants, (iii) outstanding but unexercised options to purchase common stock, or (iv) unvested restricted stock units.