Statement of Changes in Net Assets Available for Benefits - EBP 022	12 Months Ended
Dec. 31, 2025 USD ($)
EBP, Statement of Change in Net Asset Available for Benefit [Line Items]
Employee	$ 37,659,136
Employer	35,344,372
Rollovers	3,479,020
Total contributions	76,482,528
Interest income on notes receivable from participants	1,538,147
Net investment income from Plan interest in Allegheny Technologies Incorporated Master Trust	179,424,456
Net income from interest in registered investment companies	1,437,587
Total investment income	180,862,043
Total additions to net assets	258,882,718
Benefits paid to participants	(138,059,794)
Fees	(525,516)
Total deductions	(138,585,310)
Net increase in net assets available for benefits prior to net assets transferred in	120,297,408
Net assets transferred into plan, net	372,853
Net increase in net assets available for benefits	120,670,261
Net assets available for benefits at beginning of year	994,947,256
Net assets available for benefits at end of year	$ 1,115,617,517

EBP, Change In Net Asset Available For Benefit, Increase (Decrease), After Transfers

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Amount of decrease in net asset available for benefit to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Amount of decrease in net asset available for benefit from payment of benefit to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), including, but not limited to, withdrawal.

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Amount of increase in net asset available for benefit from contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Amount of increase in net asset available for benefit from cash contribution from employer of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Amount of increase in net asset available for benefit from interest income on investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Excludes interest income on note receivable from participant.

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Amount of increase in net asset available for benefit from contribution transferred from another qualified plan or from individual retirement account of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Excludes contribution for participant transmitted by employer of participant in EBP.

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Amount of net asset available for benefit transferred to (from) employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from (to) external plan.

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Amount of asset less liability available to pay benefit of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), including, but not limited to, aggregation of participants' individual account balances.

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