XML 38 R24.htm IDEA: XBRL DOCUMENT
v3.25.3

Insider Trading Arrangements | 3 Months Ended
--- | ---
Sep. 28, 2025 shares
Trading Arrangements, by Individual |
Material Terms of Trading Arrangement | During the fiscal quarter ended September 28, 2025, Robert S. Wetherbee, the Company’s Executive Chairman, entered into a pre-arranged stock trading plan on August 15, 2025, which provides for the potential sale of up to 300,000 shares of the Company’s common stock between November 18, 2025 and August 14, 2026 for his personal tax and estate planning purposes. Additionally, Timothy J. Harris, the Company’s Senior Vice President and Chief Digital and Information Officer, entered into a pre-arranged stock trading plan on August 6, 2025, which provides for the potential sale of up to 42,170 shares of the Company’s common stock between November 4, 2025 and January 30, 2026 for his personal tax and estate planning purposes. These trading plans were entered into during an open insider trading window and are intended to satisfy the affirmative defense criteria articulated by Rule 10b5-1(c) under the Securities Exchange Act of 1934, as amended, as well as the Company’s policies and procedures pertaining to transactions in Company securities.
Non-Rule 10b5-1 Arrangement Adopted | false
Rule 10b5-1 Arrangement Terminated | false
Non-Rule 10b5-1 Arrangement Terminated | false
Robert S. Wetherbee [Member] |
Trading Arrangements, by Individual |
Name | Robert S. Wetherbee
Title | Executive Chairman
Rule 10b5-1 Arrangement Adopted | true
Adoption Date | August 15, 2025
Expiration Date | August 14, 2026
Arrangement Duration | 269 days
Aggregate Available | 300,000
Timothy J. Harris [Member] |
Trading Arrangements, by Individual |
Name | Timothy J. Harris
Title | Senior Vice President and Chief Digital and Information Officer
Rule 10b5-1 Arrangement Adopted | true
Adoption Date | August 6, 2025
Expiration Date | January 30, 2026
Arrangement Duration | 87 days
Aggregate Available | 42,170

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 408 -Subsection a -Paragraph 1 + Details
Name: | ecd_MtrlTermsOfTrdArrTextBlock
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 408 -Subsection a -Paragraph 1 + Details
Name: | ecd_NonRule10b51ArrAdoptedFlag
Namespace Prefix: | ecd_
Data Type: | xbrli:booleanItemType
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 408 -Subsection a -Paragraph 1 + Details
Name: | ecd_NonRule10b51ArrTrmntdFlag
Namespace Prefix: | ecd_
Data Type: | xbrli:booleanItemType
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 408 -Subsection a -Paragraph 1 + Details
Name: | ecd_Rule10b51ArrAdoptedFlag
Namespace Prefix: | ecd_
Data Type: | xbrli:booleanItemType
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 408 -Subsection a -Paragraph 1 + Details
Name: | ecd_Rule10b51ArrTrmntdFlag
Namespace Prefix: | ecd_
Data Type: | xbrli:booleanItemType
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 408 -Subsection a -Paragraph 2 -Subparagraph A + Details
Name: | ecd_TradingArrByIndTable
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 408 -Subsection a -Paragraph 2 -Subparagraph B + Details
Name: | ecd_TrdArrAdoptionDate
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 408 -Subsection a -Paragraph 2 -Subparagraph C + Details
Name: | ecd_TrdArrDuration
Namespace Prefix: | ecd_
Data Type: | xbrli:durationItemType
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 408 -Subsection a -Paragraph 2 -Subparagraph C + Details
Name: | ecd_TrdArrExpirationDate
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 408 -Subsection a -Paragraph 2 -Subparagraph A + Details
Name: | ecd_TrdArrIndName
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 408 -Subsection a -Paragraph 2 -Subparagraph A + Details
Name: | ecd_TrdArrIndTitle
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 408 -Subsection a -Paragraph 2 -Subparagraph D + Details
Name: | ecd_TrdArrSecuritiesAggAvailAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | ecd_IndividualAxis=ati_RobertS.WetherbeeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_IndividualAxis=ati_TimothyJ.HarrisMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |