401(k) Profit Sharing Plan (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
401(k) profit sharing plan
Duration to join 401k Plan	3 months
Employee contribution on compensation, maximum	100.00%
Percentage of employees' annual contribution, eligible for employers match	100.00%	100.00%	100.00%
Additional percentage of employees' annual contribution, eligible for employers match	50.00%	50.00%	50.00%
Percentage of employees' annual contribution matched	3.00%	3.00%	3.00%
Additional percentage of employees' annual contribution matched	2.00%	2.00%	2.00%
Employer contribution amount	$ 1,800,000	$ 1,900,000	$ 1,700,000
Deferred Profit Sharing
401(k) profit sharing plan
Employer contribution amount	$ 0	$ 0	$ 0

Defined contribution plan employer additional matching contribution percent.

No definition available.

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- Definition

Defined contribution plan employers additional matching contribution annual vesting percentage.

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No definition available.

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- Definition

Duration at which an employee can begin participating in 401k Plan.

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No definition available.

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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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No definition available.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

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No definition available.

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- Definition

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

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No definition available.

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- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

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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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No definition available.

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