Employee Benefit Plan - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum contribution percentage of eligible compensation by eligible employees toward 401(k) plan	60.00%
Maximum contribution amount that employee can contribute to 401(k) plan	$ 19,500
Eligible compensation limit	$ 285,000
Defined benefit plan percentage of employer matching contribution on 6% of employee compensation	50.00%	50.00%	50.00%
Defined benefit plan employer matching contribution	$ 1,700,000	$ 5,000,000.0	$ 4,100,000
Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of employees' eligible compensation for employer matching contribution	6.00%	6.00%	6.00%

Maximum amount of employee's compensation used to figure contribution.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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+ Details

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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

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

Percentage employer matches of the employee's percentage contribution matched.

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- Definition

Maximum amount the employee may contribute to a defined contribution plan.

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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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