Percentage points added to the federal funds rate to compute the base rate

No definition available.

Name:	anss_DebtInstrumentBasisSpeadonFederalFundsRate
Namespace Prefix:	anss_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the Eurodollar rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	anss_DebtInstrumentBasisSpreadonEurodollarRate
Namespace Prefix:	anss_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Consolidated Leverage Ratio to remain compliant with credit agreement.

+ References

No definition available.

+ Details

Name:	anss_DebtInstrumentCovenantConsolidatedLeverageRatio
Namespace Prefix:	anss_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Temporarily increased consolidated leverage ratio upon completion of an acquisition.

+ References

No definition available.

+ Details

Name:	anss_DebtInstrumentCovenantConsolidatedLeverageRatioIncreased
Namespace Prefix:	anss_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Dollar amount threshold to qualify as an acquisition to trigger a temporary increase in the consolidated leverage ratio.

+ References

No definition available.

+ Details

Name:	anss_DebtInstrumentCovenantQualifiedAcquisitionAmount
Namespace Prefix:	anss_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Early repayment of debt due in 2022

+ References

No definition available.

+ Details

Name:	anss_EarlyRepaymentOfDebtDueIn2022
Namespace Prefix:	anss_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Early repayment of debt due in 2023

+ References

No definition available.

+ Details

Name:	anss_EarlyRepaymentOfDebtDueIn2023
Namespace Prefix:	anss_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Term loan principal repayment rate, increased

+ References

No definition available.

+ Details

Name:	anss_Termloanprincipalrepaymentrateincreased
Namespace Prefix:	anss_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Term loan principal repayment rate, initial

+ References

No definition available.

+ Details

Name:	anss_Termloanprincipalrepaymentrateinitial
Namespace Prefix:	anss_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69C
-URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69B
-URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

+ Details

Name:	us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
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

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityLineItems
Namespace Prefix:	us-gaap_
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

+ Details

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

- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

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

- Definition

Weighted average interest rate of long-term debt outstanding calculated over time.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtWeightedAverageInterestRateOverTime
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

+ Details

Name:	us-gaap_LongtermDebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

+ Details

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

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=anss_LivermoreSoftwareTechnologyCorporationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=anss_AnalyticalGraphicsIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_EurodollarMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Debt (Details) - USD ($)			12 Months Ended
Debt (Details) - USD ($)	Jun. 30, 2021	Jan. 06, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 01, 2020	Nov. 01, 2019
Debt Disclosure [Line Items]
Term loan principal repayment rate, initial			1.25%
Term loan principal repayment rate, increased			2.50%
Weighted-average interest rate over time			1.37%	2.09%
Weighted-average interest rate at a point in time			1.35%
Consolidated leverage ratio			3.50
Consolidated leverage ratio increased			4.00
Qualified acquisition amount			$ 250,000,000
Long-term debt			753,576,000	$ 798,118,000
Unamortized debt issuance cost			1,400,000	$ 1,900,000
Livermore Software Technology Corporation
Debt Disclosure [Line Items]
Unsecured debt						$ 500,000,000
Early debt repayment	$ 26,000,000	$ 75,000,000
Early repayment of debt due in 2022		25,000,000
Early repayment of debt due in 2023		$ 50,000,000
Analytical Graphics, Inc.
Debt Disclosure [Line Items]
Unsecured debt					$ 375,000,000
Early debt repayment	19,000,000
Early repayment of debt due in 2022	18,800,000
Early repayment of debt due in 2023	$ 200,000
Revolving Credit Facility
Debt Disclosure [Line Items]
Line of credit facility, maximum borrowing capacity			500,000,000
Outstanding borrowings under the credit agreement			0
Letter of Credit
Debt Disclosure [Line Items]
Line of credit facility, maximum borrowing capacity			$ 50,000,000
Base Rate
Debt Disclosure [Line Items]
Debt instrument, basis spread on federal funds rate			0.50%
Debt instrument, basis spread on Eurodollar rate			1.00%
Base Rate \| Minimum
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate			0.125%
Base Rate \| Maximum
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate			0.75%
Eurodollar \| Minimum
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate			1.125%
Eurodollar \| Maximum
Debt Disclosure [Line Items]
Debt instrument, basis spread on variable rate			1.75%