Leases - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Lease cost
Total operating lease cost	$ 2,486	$ 2,941	$ 7,767	$ 7,798
Depreciation of leased assets	321	324	964	961
Interest on lease liabilities	1,177	1,214	3,561	3,668
Total finance lease cost	1,498	1,538	4,525	4,629
Total lease cost	3,984	4,479	12,292	12,427
Short-term lease and variable lease costs	300	600	1,600	1,600
Product / services*
Lease cost
Total operating lease cost	1,664	2,041	5,186	5,328
Research and development
Lease cost
Total operating lease cost	127	183	453	426
Sales and marketing*
Lease cost
Total operating lease cost	463	419	1,365	1,231
General and administrative*
Lease cost
Total operating lease cost	$ 232	$ 298	$ 763	$ 813

Amount of finance lease cost recognized by lessee for lease contract.

No definition available.

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Namespace Prefix:	acls_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of short-term and variable lease cost.

+ References

No definition available.

+ Details

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Namespace Prefix:	acls_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest expense on finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 53
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479589/842-20-55-53

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-4

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

+ Details

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Balance Type:	debit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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