Defined Contribution Plan, Employee Contributions, Percentage of Eligible Compensation

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Number of shares available to issuance under the employee stock purchase plan.

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Share based compensation employee stock purchase plan contribution percentage.

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The number of share available for issuance.

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- Definition

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

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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- Definition

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

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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.

+ References

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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.

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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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- Definition

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

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Share-Based Compensation and Employee Benefit Plans - Textual (Details) - USD ($) shares in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of stock options exercised		$ 51,000	$ 384,000	$ 853,000
Unrecognized compensation cost - option		0
Stock based compensation expense		$ 10,585,000	$ 6,062,000	$ 5,670,000
Shares purchased under ESPP		72	13	11
Employee stock purchase plan available		236		1,206
Percentage of contribution for annual compensation		100.00%
Percentage of match of all employee contribution		50.00%
Total matching contribution to plan		$ 1,317,000	$ 1,118,000	$ 1,047,000
Rudolph 2018 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price of common stock as percentage of fair market value	95.00%
Stock based compensation expense		$ 0	$ 0	$ 0
Nanometrics 2003 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price of common stock as percentage of fair market value		85.00%
Stock based compensation expense		$ 165,000
Maximum percentage of salary withholdings		10.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of match on employee salary		6.00%
Maximum [Member] \| Rudolph 2018 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Eligible compensation deduction percentage on pay for purchase of common stock	15.00%
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to restricted stock units granted		$ 22,230,000
Unrecognized compensation cost related to restricted stock units, weighted average period		1 year 10 months 24 days
Rudolph 2018 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share authorized available for grants		2,709
Shares of common stock available for issuance pursuant to future grants		2,478	2,680
Rudolph 2018 Stock Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Employees [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		3 years
Rudolph 2018 Stock Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Employees [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		5 years
Rudolph 2018 Stock Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		1 year
Rudolph 2018 Stock Plan [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		5 years
Options expiration period		10 years
Rudolph 2009 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share authorized available for grants		4,711
Shares of common stock available for issuance pursuant to future grants		0	0
Rudolph 2009 Stock Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Employees [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		3 years
Rudolph 2009 Stock Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Employees [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		5 years
Rudolph 2009 Stock Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		1 year
Rudolph 2009 Stock Plan [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		5 years
Options expiration period		10 years
Nanometrics 2005 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share authorized available for grants		4,714
Shares of common stock available for issuance pursuant to future grants		1,253
Nanometrics 2005 Equity Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		3 years
Nanometrics 2005 Equity Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member] \| Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		1 year
Nanometrics 2005 Equity Incentive Plan [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting		3 years
Options expiration period		10 years