Stockholders' Equity - Equity Incentive Award Plan (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Feb. 28, 2025	Sep. 27, 2025	Sep. 27, 2025	Sep. 28, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant (in shares)		3,800,000	3,800,000
Stock-based compensation			$ 65,976	$ 48,686
Stock options exercised (in shares)		700,000	1,100,000
Weighted-average exercise price per share, stock options (in dollars per share)		$ 11.09	$ 15.85
Unrecognized stock-based compensation expense, stock options		$ 89,000	$ 89,000
Recognition period			2 years 3 months 18 days
2019 Equity Incentive Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in the number of shares of common stock issuable (in shares)		4,000,000	4,000,000
Performance Based Stock Options \| Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)	3,100,000
Weighted-average grant date fair value (in dollars per share)	$ 39.68
Award performance period	1 year
Stock-based compensation		$ 6,600	$ 17,400
Performance Based Stock Options \| Period One \| Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage	25.00%
Award vesting period	1 year
Net income per share, target achievement performance threshold percentage	50.00%
Number of shares granted if target achievement performance threshold percentage	50.00%
Target achievement threshold for shares award sliding scale	100.00%
Shares award weighted percent	50.00%
Maximum combined payout percent	100.00%
Performance Based Stock Options \| Period Two \| Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage	75.00%
Award vesting period	36 months
Net income per share, target achievement performance threshold percentage	50.00%
Number of shares granted if target achievement performance threshold percentage	75.00%
Stock Options \| Period One \| Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)		400,000	1,000,000
Weighted-average grant date fair value (in dollars per share)		$ 56.67	$ 47.39
Award vesting rights, percentage		25.00%
Award vesting period			3 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized stock-based compensation expense, stock options		$ 1,000	$ 1,000
Recognition period			7 months 6 days
Restricted Stock \| Board Of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			1 year
Restricted stock awards, granted (in shares)			38,000
Weighted-average exercise price per share, restricted stock awards (in dollars per share)		$ 42.65	$ 42.65

CALIX, INC 10-Q