Represents the continuous service period required for eligibility of employees to participate under the plan.

No definition available.

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- Definition

Represents the vesting period for employer matching contribution under the plan.

+ References

No definition available.

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- Definition

Represents the minimum age for employees to contribute catch up contributions under IRS limits.

+ References

No definition available.

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- Definition

Multiemployer Plan, Pension, Significant, Funded Status, Percentage

+ References

No definition available.

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
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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.

+ References

No definition available.

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- Definition

Amount of cost for employer contribution to multiemployer pension plan determined to be individually significant.

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-Name Accounting Standards Codification
-Topic 715
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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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Employee Benefit Plans (Details)	12 Months Ended
Employee Benefit Plans (Details)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Multiemployer Plans [Line Items]
Minimum age for employees to contribute catch up contributions under IRS limits	50 years
Continuous service period required for eligibility of employees to participate under the plan	3 months
Maximum Company match amount of employee contributions matched up to 6% of annual compensation (as a percent)	50.00%
Maximum percentage of employee's annual compensation for which the company contributes a matching contribution (as a percent)	6.00%
Vesting period for employer matching contribution	5 years
Contribution under 401(k) savings plan	$ 1,100,000	$ 4,100,000	$ 3,900,000
Multiemployer Plans, Pension \| Boilermakers and Pipefitters Plans
Multiemployer Plans [Line Items]
Contributions to multi-employer defined benefit plan	$ 0	$ 0	$ 600,000
Multiemployer Plans, Pension \| Boilermakers and Pipefitters Plans \| Minimum
Multiemployer Plans [Line Items]
Multiemployer plan funded status percentage	0.66
Multiemployer Plans, Pension \| Boilermakers and Pipefitters Plans \| Maximum
Multiemployer Plans [Line Items]
Multiemployer plan funded status percentage	0.75