Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

Name:	us-gaap_DebtInstrumentAxis=atmu_AtmusCreditAgreementMember
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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
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- Details

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- Details

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- Details

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DEBT AND BORROWING ARRANGEMENTS - Narrative (Details) - USD ($)			3 Months Ended
	May 30, 2024	May 30, 2023	Mar. 31, 2025	Dec. 31, 2024	Feb. 15, 2023
Line of Credit Facility [Line Items]
Long-term debt fair value			$ 588,800,000
Revolving Credit Facility \| Atmus Credit Agreement \| Line of Credit
Line of Credit Facility [Line Items]
Long-term debt proceeds	$ 650,000,000
Interest rate			0.10%
Borrowed amount		$ 650,000,000
Facility amount					$ 1,000,000,000.0
Revolving Credit Facility \| Atmus Credit Agreement \| Line of Credit \| Minimum
Line of Credit Facility [Line Items]
Interest rate			1.125%
Revolving Credit Facility \| Atmus Credit Agreement \| Line of Credit \| Maximum
Line of Credit Facility [Line Items]
Interest rate			1.75%
Revolving Credit Facility \| Atmus Term Loan Facility \| Line of Credit
Line of Credit Facility [Line Items]
Borrowed amount			$ 588,800,000
Facility amount			600,000,000.0	$ 600,000,000.0	600,000,000
Revolving Credit Facility \| Atmus Revolving Credit Facility \| Line of Credit
Line of Credit Facility [Line Items]
Borrowed amount			0
Facility amount			400,000,000.0	$ 400,000,000.0	$ 400,000,000
Letters of credit outstanding, amount			0
Revolving Credit Facility \| Atmus Revolving Credit Facility \| Letter of Credit
Line of Credit Facility [Line Items]
Facility amount			$ 50,000,000.0