XML 78 R71.htm IDEA: XBRL DOCUMENT v3.25.3

Accumulated Other Comprehensive Income (Loss) - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 27, 2025	Sep. 28, 2024
Accumulated Other Comprehensive Loss [Abstract]
Tax Effect Marketable Securities	$ 117	$ 358

X

- Definition

Accumulated Other Comprehensive Loss [Abstract]

+ References

No definition available.

+ Details

Name:	onto_AccumulatedOtherComprehensiveLossAbstract
Namespace Prefix:	onto_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

tax effects on net income of amounts recorded in other comprehensive loss for net unrealized losses on available-for-sale marketable securities.

+ References

No definition available.

+ Details

Name:	onto_TaxEffectMarketableSecurities
Namespace Prefix:	onto_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration