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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No definition available.

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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

+ References

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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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-Section S99
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- Definition

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

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-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

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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-Name Accounting Standards Codification
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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 weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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, 2019	Dec. 31, 2018	Dec. 31, 2017
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
Restricted stock granted	843,000	681,000	866,000
Stock-based compensation expense	$ 116,190,000	$ 83,346,000	$ 53,154,000
Employee Stock Option
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total unrecognized estimated unvested stock option compensation cost	$ 1,000,000.0
Weighted-average period of recognition of unrecognized compensation cost (years)	1 year
Performance Shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock unit vesting period	3 years
RSU grant date fair value	$ 238.99	$ 191.76	$ 120.94
Restricted Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense	$ 109,900,000	$ 77,400,000	$ 46,300,000
Director Restricted Stock Units
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock granted	11,259	13,632	18,018
RSU grant date fair value	$ 187.53	$ 165.71	$ 123.38
Stock-based compensation expense	$ 2,500,000	$ 2,300,000	$ 2,600,000
Market and Service Condition Stock Units
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock unit vesting period	3 years
Minimum \| Restricted Stock Units (RSUs)
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
Maximum \| Restricted Stock Units (RSUs)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Restricted stock unit vesting period	4 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
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	1,600,000
Stock-based compensation expense	$ 2,000,000.0	$ 1,800,000	$ 1,200,000
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%