Revenue from Contracts with Customers - Changes in Deferred Revenue (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023
Movement in Deferred Revenue [Roll Forward]
Beginning balance	$ 479,754	$ 435,758
Acquired deferred revenue	0	7,910
Deferral of revenue	1,038,334	961,520
Recognition of revenue	(1,060,743)	(1,006,046)
Currency translation	(11,425)	(2,636)
Ending balance	$ 445,920	$ 396,506

Contract With Customer, Liability, Additions

No definition available.

Name:	anss_ContractWithCustomerLiabilityAdditions
Namespace Prefix:	anss_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Contract With Customer, Liability, Revenue Recognized, Including Amounts Not Previously Included

+ References

No definition available.

+ Details

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

- Definition

Contract With Customer, Liability, Translation Gain (Loss)

+ References

No definition available.

+ Details

Name:	anss_ContractWithCustomerLiabilityTranslationGainLoss
Namespace Prefix:	anss_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479837/606-10-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-8

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479837/606-10-45-2

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration from customer has been received or is due, from business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-10

+ Details

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

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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Period Type:	duration