XML 24 R2.htm IDEA: XBRL DOCUMENT
v3.24.1

Pay vs Performance Disclosure | 12 Months Ended
--- | ---
Dec. 31, 2023 USD ($) shares | Dec. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($) shares | Dec. 31, 2020 USD ($) shares
Pay vs Performance Disclosure |  |  |  |
Pay vs Performance Disclosure, Table | We are required by SEC rules to disclose the following information regarding compensation paid to our NEOs. The amounts set forth below under the headings “Compensation Actually Paid to CEO” and “Average Compensation Actually Paid for NEOs” have been calculated in a manner consistent with Item 402(v) of Regulation S-K. The tables in footnote (2) below set forth the adjustments from the Total Compensation for each NEO reported in the Summary Compensation Table above. The following table sets forth additional compensation information of our Chief Executive Officer (CEO) and our non-CEO NEOs along with total shareholder return, net income and total revenue performance results for fiscal years 2020, 2021, 2022 and 2023.
|  |  |  |  | Value of Initial Fixed $100 Investment Based On: |  |
Year (1) | Summary Compensation Table Total For CEO | Compensation Actually Paid to CEO (5) | Average Summary Compensation Table Total For NEOs | Average Compensation Actually Paid to NEOs (5)(2) | Total Shareholder Return (3) | Peer Group Total Shareholder Return (3) | Net Income (in thousands) (4) | Total Revenue (in thousands)(4)
2023 | $5,646,028 | $21,220,183 | $1,282,972 | $2,783,035 | $318.23 | $165.64 | $121,159 | $815,868
2022 | $5,313,301 | $2,086,925 | $1,129,974 | $711,974 | $86.27 | $42.98 | $223,334 | $1,005,183
2021 | $5,134,310 | $13,985,674 | $1,069,940 | $2,149,621 | $176.97 | $125.09 | $142,349 | $788,899
2020 | $3,763,688 | $4,453,187 | $934,489 | $1,463,581 | $30.11 | $56.09 | $31,025 | $556,496
Named Executive Officers, Footnote | (1) The CEO and NEOs included in the above compensation columns reflect the following:
Year | CEO | NEOs
2023 | Michael P. Plisinski | Mark R. Slicer, Yoon Ah E. Oh, Srinivas Vedula, Ramil Yaldaei
2022 | Michael P. Plisinski | Mark R. Slicer, James (Cody) Harlow, Robert Fiordalice, Yoon Ah E. Oh, Steven R. Roth
2021 | Michael P. Plisinski | Steven R. Roth, Rollin Kocher, Kevin Heidrich, Robert A. Koch, Yoon Ah E. Oh
2020 | Michael P. Plisinski | Steven R. Roth, Rollin Kocher, Kevin Heidrich, Robert A. Koch
Peer Group Issuers, Footnote | (3) Company and Peer Group TSR reflects the Company’s peer group (PHLX Semiconductor Index) as reflected in our Annual Report on the Form 10-K pursuant to Item 201(e) of Regulation S-K for the fiscal year ended December 30, 2023. Each year reflects what the cumulative value of $100 would be, including the reinvestment of dividends, if such amount were invested on December 31, 2019. |  |  |
PEO Total Compensation Amount | $ 5,646,028 | $ 5,313,301 | $ 5,134,310 | $ 3,763,688
PEO Actually Paid Compensation Amount | $ 21,220,183 | 2,086,925 | 13,985,674 | 4,453,187
Adjustment To PEO Compensation, Footnote | “Compensation Actually Paid” to the CEO reflects the following adjustments from Total Compensation reported in the Summary Compensation Table:
CEO | 2023 | 2022 | 2021 | 2020
Total Reported in Summary Compensation Table (SCT) | $5,646,028 | $5,313,301 | $5,134,310 | $3,763,688
Less, Value of Stock & Option Awards Reported in SCT | ($4,327,136) | ($3,977,905) | ($3,487,747) | ($2,672,777)
Less, Change in Pension Value and Non-Qualified Deferred Compensation Earnings in SCT | — | — | — | —
Plus, Pension Service Cost and impact of Pension Plan Amendments | — | — | — | —
Plus, Year-End value of Awards Granted in Fiscal Year that are Unvested and Outstanding | $10,231,429 | $2,764,863 | $6,761,134 | $2,941,125
Plus, Change in Fair Value of Prior Year awards that are Outstanding and Unvested | $8,298,325 | ($2,584,704) | $5,241,435 | $318,972
Plus, FMV of Awards Granted this Year and that Vested this Year | — | — | — | —
Plus, Change in Fair Value (from Prior Year-End) of Prior Year awards that Vested this year | $1,371,538 | $571,370 | $336,542 | $102,179
Less, Prior Year Fair Value of Prior Year awards that failed to vest this year | — | — | — | —
Total Adjustments | $15,574,155 | ($3,226,376) | $8,851,364 | $689,499
"Compensation Actually Paid" | $21,220,183 | $2,086,925 | $13,985,674 | $4,453,187
Non-PEO NEO Average Total Compensation Amount | $ 1,282,972 | 1,129,974 | 1,069,940 | 934,489
Non-PEO NEO Average Compensation Actually Paid Amount | $ 2,783,035 | 711,974 | 2,149,621 | 1,463,581
Adjustment to Non-PEO NEO Compensation Footnote | The average “Compensation Actually Paid” to the NEOs reflects the following adjustments from Total Compensation reported in the Summary Compensation Table:
NEO Average | 2023 | 2022 | 2021 | 2020
Total Reported in Summary Compensation Table (SCT) | $1,282,972 | $1,129,974 | $1,069,940 | $934,489
Less, Value of Stock & Option Awards Reported in SCT | ($721,165) | ($577,372) | ($533,902) | ($435,715)
Less, Change in Pension Value and Non-Qualified Deferred Compensation Earnings in SCT | — | — | — | —
Plus, Pension Service Cost and impact of Pension Plan Amendments | — | — | — | —
Plus, Year-End value of Awards Granted in Fiscal Year that are Unvested and Outstanding | $1,508,382 | $436,885 | $879,706 | $479,458
Plus, Change in Fair Value of Prior Year awards that are Outstanding and Unvested | $613,125 | ($143,057) | $665,069 | $487,384
Plus, FMV of Awards Granted this Year and that Vested this Year | — | — | — | —
Plus, Change in Fair Value (from Prior Year-End) of Prior Year awards that Vested this year | $99,722 | ($134,457) | $68,807 | ($2,036)
Less, Prior Year Fair Value of Prior Year awards that failed to vest this year | — | — | — | —
Total Adjustments | $1,500,064 | ($418,000) | $1,079,680 | $529,092
"Compensation Actually Paid" | $2,783,035 | $711,974 | $2,149,621 | $1,463,581
Equity Valuation Assumption Difference, Footnote | (5) Fair value or change in fair value, as applicable, of equity awards in the “Compensation Actually Paid” columns was determined by reference to (1) for RSU awards, closing price on applicable year-end dates or, in the case of vesting dates, the actual vesting price, (2) for TSR-based PSU awards, the fair value calculated by a Monte Carlo simulation model as of the applicable year-end date(s) or, in the case of vesting date, the actual vesting price and probability of achievement. For the portion of “Compensation Actually Paid” that is based on year-end stock prices, the following prices were used: for 2023 : $152.90 (124.6% increase from prior year) for 2022: $68.09 (32.7% reduction from prior year), for 2021: $101.23 (110.8% increase from prior year), and for 2020: $48.02 (1.0% increase from prior year). |  |  |
Tabular List, Table | The table below lists our most important performance measures used to link “Compensation Actually Paid” for our NEOs to Company performance, over the fiscal year ending December 30, 2023. Both Total Revenue and non-GAAP operating income factor into the annual cash incentive compensation paid to NEOs and Company TSR over two- and three-year measurement periods determine the ultimate value of PSUs awarded to NEOs. For a further discussion of how each of these financial measures relates to NEO compensation and for a reconciliation of the non-GAAP measure as compared to the GAAP measure reflected in our audited financial statements, see our “Compensation Discussion and Analysis” beginning on page 28 of this proxy statement. The performance measures included in this table are not ranked by relative importance.
Most Important Financial Measures
Total Revenue
Non-GAAP Operating Income (1)
Total Shareholder Return
(1) Refer to footnote (1) on page 40 of this proxy statement for a reconciliation of non-GAAP operating income to the most comparable GAAP measure. |  |  |
Total Shareholder Return Amount | $ 318.23 | 86.27 | 176.97 | 30.11
Peer Group Total Shareholder Return Amount | 165.64 | 42.98 | 125.09 | 56.09
Net Income (Loss) | $ 121,159 | 223,334 | 142,349 | 31,025
Additional 402(v) Disclosure | Our TSR lagged the TSR for our peer group in 2020 but increased significantly in 2021 both in terms of real dollars and in relation to our peer group TSR, which our TSR exceeded by approximately 40%. In 2022, the dollar value of our TSR dropped but was nonetheless over 100% greater than our peer group TSR. From 2022 to 2023 our TSR increased by over 250% and was almost twice that of our peer group TSR. There is a positive relationship between TSR and “Compensation Actually Paid” to our CEO and the other NEOs between 2020 and 2021, when both metrics increased, between 2021 and 2022, when both metrics dropped, despite our TSR equaling approximately twice our peer group TSR, and between 2022 and 2023, when both metrics increased again. The following chart illustrates the relationship between our Compensation Actually Paid and TSR: Compensation Actually Paid and Net Income There is a positive relationship between Net Income and “Compensation Actually Paid” to our CEO and the other NEOs between 2020 and 2021, when both metrics increased. There is an inverse relationship between Net Income and “Compensation Actually Paid” to our CEO and the other NEOs between 2021 and 2022 when Net Income increased, but “Compensation Actually Paid” decreased. There is, again, an inverse relationship between Net Income and “Compensation Actually Paid” to our CEO and other NEOs between 2022 and 2023 when Net Income decreased but “Compensation Actually Paid” increased. The following chart illustrates the relationship between our Compensation Actually Paid and Net Income: Compensation Actually Paid and Total Revenue We chose Total Revenue as our Company Selected Measure for evaluating Pay versus Performance because it is a key metric, along with non-GAAP operating income, in determining the annual cash incentive compensation paid to the CEO and other NEOs. From 2020 to 2021 there is a positive relationship between Total Revenue and “Compensation Actually Paid,” when both metrics increased, an inverse relationship between 2021 and 2022 when Total Revenue increased, but “Compensation Actually Paid” to our CEO and the other NEOs decreased, and an inverse relationship between 2022 and 2023 when Total Revenue decreased, but “Compensation Actually Paid” to our CEO and the other NEOs increased. Much of the increase in CEO and NEO “Compensation Actually Paid” from 2022 to 2023 is attributable to the significant increase in the Company’s stock price during 2023. The following chart illustrates the relationship between our Compensation Actually Paid and Total Revenue: |  |  |
TSR-based PSU Vested Footnote | (2) In 2023, tranches of the TSR-based PSU awards from 2021 and 2020 vested. None of the NEOs, except for the CEO, was in his or her current role in 2020 or 2021 at the time the PSU awards were granted. Therefore no NEO, except for the CEO, received Common Stock from the vesting of PSU awards in 2023. |  |  |
Net Income Total Revenue Footnote | (4) The dollar amounts reported represent the amount of net income and total revenue reflected in our audited financial statements for each covered fiscal year. |  |  |
Total Revenue | $ 815,868 | $ 1,005,183 | $ 788,899 | $ 556,496
Year End Stock Price | shares | 152.9 | 68.09 | 101.23 | 48.02
Stock Price Performance | 1.24 | 0.327 | 1.108 | 0.01
Measure:: 1 |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Name | Total Revenue |  |  |
Measure:: 2 |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Name | Non-GAAP Operating Income (1) |  |  |
Measure:: 3 |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Name | Total Shareholder Return |  |  |
PEO |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | $ 15,574,155 | $ (3,226,376) | $ 8,851,364 | $ 689,499
PEO | Value Of Stock And Option Awards In Summary Compensation Table Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (4,327,136) | (3,977,905) | (3,487,747) | (2,672,777)
PEO | Change In Pension Value And Non Qualified Deferred Compensation Earnings Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
PEO | Pension Service Cost And Impact Of Pension Plan Adjustments Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
PEO | Year End Value Of Awards Granted In Fiscal Year That Are Unvested And Outstanding Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 10,231,429 | 2,764,863 | 6,761,134 | 2,941,125
PEO | Change In Fair Value Of Prior Year Awards That Are Outstanding And Unvested Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 8,298,325 | (2,584,704) | 5,241,435 | 318,972
PEO | F M V Of Awards Granted This Year And That Vested This Year Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
PEO | Change In Fair Value From Prior Year End Of Prior Year Awards That Vested This Year Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 1,371,538 | 571,370 | 336,542 | 102,179
PEO | Prior Year Fair Value Of Prior Year Awards That Failed To Vest This Year Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
Non-PEO NEO |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 1,500,064 | (418,000) | 1,079,680 | 529,092
Non-PEO NEO | Value Of Stock And Option Awards In Summary Compensation Table Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (721,165) | (577,372) | (533,902) | (435,715)
Non-PEO NEO | Change In Pension Value And Non Qualified Deferred Compensation Earnings Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
Non-PEO NEO | Pension Service Cost And Impact Of Pension Plan Adjustments Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
Non-PEO NEO | Year End Value Of Awards Granted In Fiscal Year That Are Unvested And Outstanding Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 1,508,382 | 436,885 | 879,706 | 479,458
Non-PEO NEO | Change In Fair Value Of Prior Year Awards That Are Outstanding And Unvested Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 613,125 | (143,057) | 665,069 | 487,384
Non-PEO NEO | F M V Of Awards Granted This Year And That Vested This Year Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |
Non-PEO NEO | Change In Fair Value From Prior Year End Of Prior Year Awards That Vested This Year Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 99,722 | (134,457) | 68,807 | 2,036
Non-PEO NEO | Prior Year Fair Value Of Prior Year Awards That Failed To Vest This Year Member |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount |  |  |  |

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v + Details
Name: | ecd_Additional402vDisclosureTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 3 + Details
Name: | ecd_AdjToCompAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 3 + Details
Name: | ecd_AdjToNonPeoNeoCompFnTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 3 + Details
Name: | ecd_AdjToPeoCompFnTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 4 + Details
Name: | ecd_EquityValuationAssumptionDifferenceFnTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph vi + Details
Name: | ecd_MeasureName
Namespace Prefix: | ecd_
Data Type: | xbrli:normalizedStringItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 3 + Details
Name: | ecd_NamedExecutiveOfficersFnTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph iii + Details
Name: | ecd_NonPeoNeoAvgCompActuallyPaidAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph ii + Details
Name: | ecd_NonPeoNeoAvgTotalCompAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph iv + Details
Name: | ecd_PeerGroupIssuersFnTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph iv + Details
Name: | ecd_PeerGroupTotalShareholderRtnAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph iii + Details
Name: | ecd_PeoActuallyPaidCompAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph ii + Details
Name: | ecd_PeoTotalCompAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 1 + Details
Name: | ecd_PvpTable
Namespace Prefix: | ecd_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 1 + Details
Name: | ecd_PvpTableTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 6 + Details
Name: | ecd_TabularListTableTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph iv + Details
Name: | ecd_TotalShareholderRtnAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Net Income Total Revenue Footnote + References No definition available. + Details
Name: | onto_NetIncomeTotalRevenueFootnote
Namespace Prefix: | onto_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock Price Performance + References No definition available. + Details
Name: | onto_StockPricePerformance
Namespace Prefix: | onto_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total Revenue + References No definition available. + Details
Name: | onto_TotalRevenue
Namespace Prefix: | onto_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition TSR-based PSU Vested Footnote + References No definition available. + Details
Name: | onto_TsrBasedPsuVestedFootnote
Namespace Prefix: | onto_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Year End Stock Price + References No definition available. + Details
Name: | onto_YearEndStockPrice
Namespace Prefix: | onto_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(g)(1)(ii)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 323 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481687/323-10-50-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482907/825-10-50-28 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482765/220-10-50-6 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 250 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483443/250-10-50-3 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 250 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483443/250-10-50-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 65 -Paragraph 1 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480175/815-40-65-1 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 250 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483443/250-10-50-8 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 250 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483443/250-10-50-9 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 250 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483443/250-10-50-11 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Topic 250 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483443/250-10-50-11 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Topic 250 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483443/250-10-50-4 Reference 13: http://www.xbrl.org/2003/role/exampleRef -Topic 946 -SubTopic 830 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480167/946-830-55-10 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section 45 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483581/946-220-45-7 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(18)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482810/280-10-50-22 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07(9)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-09(1)(d)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483575/946-220-S99-3 Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(i)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A Reference 20: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(ii)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(iii)(A)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A Reference 22: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(iv)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A Reference 23: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(5)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1A Reference 24: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(i)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B Reference 25: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(iii)(A)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B Reference 26: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(iii)(B)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B Reference 27: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(iv)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B Reference 28: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(5)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480097/470-10-S99-1B Reference 29: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 30 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482810/280-10-50-30 Reference 30: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 32 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482810/280-10-50-32 Reference 31: http://www.xbrl.org/2003/role/disclosureRef -Topic 260 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 60B -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482689/260-10-45-60B Reference 32: http://www.xbrl.org/2003/role/exampleRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 31 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482810/280-10-50-31 Reference 33: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 32 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482810/280-10-50-32 Reference 34: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483499/205-20-50-7 Reference 35: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-28 Reference 36: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-1A Reference 37: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1B -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482790/220-10-45-1B Reference 38: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(20)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2 Reference 39: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(22)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1 + Details
Name: | us-gaap_NetIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | ecd_MeasureAxis=1
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_MeasureAxis=2
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_MeasureAxis=3
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_ExecutiveCategoryAxis=ecd_PeoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=onto_ValueOfStockAndOptionAwardsInSummaryCompensationTableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=onto_ChangeInPensionValueAndNonQualifiedDeferredCompensationEarningsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=onto_PensionServiceCostAndImpactOfPensionPlanAdjustmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=onto_YearEndValueOfAwardsGrantedInFiscalYearThatAreUnvestedAndOutstandingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=onto_ChangeInFairValueOfPriorYearAwardsThatAreOutstandingAndUnvestedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=onto_FMVOfAwardsGrantedThisYearAndThatVestedThisYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=onto_ChangeInFairValueFromPriorYearEndOfPriorYearAwardsThatVestedThisYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=onto_PriorYearFairValueOfPriorYearAwardsThatFailedToVestThisYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_ExecutiveCategoryAxis=ecd_NonPeoNeoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |