Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Jan. 03, 2020	Dec. 28, 2018	Dec. 29, 2017
Income Taxes [Line Items]
Income Tax Expense (Benefit)	$ (1,022,000)	$ 1,671,000	$ (157,000)
Increase (Decrease) Deferred Tax Assets Valuation Allowance	(5,472,000)	2,418,000	(16,789,000)
Increase (Decrease) In Foreign Deferred Tax Liabilities	(46,000)	36,000	(47,000)
Income tax reconciliation of global intangible low-taxed income	$ 16,100,000	7,700,000
Percentage of deduction in GILTI	50.00%
Deferred Tax Assets, Net	$ 3,750,000	256,000
Taxes Payable	2,572,000	820,000
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax	136,000
Operating Loss Carryforwards	$ 129,000,000
Operating Loss Carry Forwards Expiration Term	expire in varying amounts between 2020 and 2037
Operating Loss Carryforwards, Limitations on Use	The California net operating loss carryforwards expire in varying amounts between 2028 and 2039
Stock-based compensation	$ 3,455,000	2,489,000
STAAR Surgical AG
Income Taxes [Line Items]
Deferred Tax Liabilities, Net	658,000	922,000
Swiss
Income Taxes [Line Items]
Deferred Tax Liabilities, Net	658,000	922,000
Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries	1,295,000	1,282,000
JAPAN
Income Taxes [Line Items]
Deferred Tax Assets, Net	896,000	905,000
Stock-based compensation	46,000	44,000
US
Income Taxes [Line Items]
Deferred Tax Assets, Net	3,139,000	273,000
California
Income Taxes [Line Items]
Operating Loss Carryforwards	33,000,000
State
Income Taxes [Line Items]
Increase (Decrease) Deferred Tax Assets	387,000
Increase (Decrease) Deferred Tax Assets Valuation Allowance	(760,000)	$ 447,000	$ (646,000)
Deferred Tax Assets, Net	373,000
Deferred tax assets, valuation allowance	6,643,000
Federal and State
Income Taxes [Line Items]
Deferred Tax Assets, Net	3,512,000
Federal
Income Taxes [Line Items]
Deferred Tax Assets, Net	3,003,000
Deferred tax assets, valuation allowance	33,813,000
Deferred tax asset, in foreign tax credits and foreign withholding taxes	$ 2,285,000