Exercise Price Minimum Percent of Fair Market Value Threshold for Issuance of I S O to 10% shareholder

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- Definition

Maximum Term After Sale Event Where Awards Fully Vest When Service Relationship Terminated Without Cause

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No definition available.

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- Definition

Maximum Term That May Be Granted To Terminated Employee To Exercise Awards Prior To Termination

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- Definition

Share based compensation arrangement by share based payment award, award expiration dating conditional.

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- Definition

Eligibility criteria for participation in the Employee Stock Purchase Plan expressed as a percentage of the combined voting power of all classes of stock of the Company owned by any individual employee.

+ References

No definition available.

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- Definition

Maximum dollar amount of common stock purchasable through the employee stock purchase plan in a calendar year under applicable tax rules.

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued as of Date

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No definition available.

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- Definition

Threshold of total combined voting interest of all class of stock for ISO.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- 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.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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Stock-Based Compensation - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares authorized for grant under the plan	39,800,000
Percentage of voting interest to be held by optionee	10.00%
Exercise price as a percentage of fair value at the time of grant	110.00%
Maximum months after sale event where awards fully vest when service relationship terminated without cause	18 months
Minimum number of days that may be granted to terminated employee to exercise awards prior to termination	15 days
Total unrecognized estimated unvested stock awards	$ 160,700,000
Weighted-average period of recognition of unrecognized compensation cost (years)	1 year 4 months 24 days
Stock-based compensation expense	$ 145,615,000	$ 116,190,000	$ 83,346,000
Performance Shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock unit vesting period	3 years
Restricted Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense	$ 138,300,000	109,900,000	77,400,000
Restricted Stock Units (RSUs)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock unit vesting period	3 years
Director Restricted Stock Units
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense	$ 2,200,000	2,500,000	2,300,000
Market and Service Condition Stock Units
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock unit vesting period	3 years
Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expiration period of options from the date of grant	10 years
Expiration period for optionee who meets the 10% criteria	5 years
ANSYS 1996 Employee Stock Purchase Plan \| Employee Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares authorized for grant under the plan	1,800,000
Expiration period of options from the date of grant	6 months
Stock-based compensation expense	$ 4,100,000	$ 2,000,000.0	$ 1,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	100,000
Share-based compensation arrangement by share-based payment award, maximum employee subscription rate	10.00%
Share-based compensation arrangement by share-based payment award, maximum number of shares per employee	3,840
Share-based compensation arrangement by share-based payment award, purchase price of common stock, percent	90.00%
Share-based compensation arrangement by share-based payment award, maximum dollar amount of common stock purchasable in a calendar year	$ 25,000
Share-based compensation arrangement by share-based payment award, shares issued as of date	1,700,000
ANSYS 1996 Employee Stock Purchase Plan \| Maximum \| Employee Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, eligibility, ownership percentage	5.00%