Number of persons employed by the Entity

No definition available.

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- Definition

Represents the approximate number of active employees in employee groups.

+ References

No definition available.

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- Definition

Amount of allowance for credit loss on accounts receivable.

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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.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Carrying value as of the balance sheet date of obligations and payables pertaining to claims incurred of a workers compensation nature. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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Commitments and Contingencies (Details)	12 Months Ended
Commitments and Contingencies (Details)	Dec. 31, 2019 USD ($) employee	Dec. 31, 2018 USD ($)	Dec. 31, 2017
Concentration Risk and Significant Customers
Accrued workers' compensation liability \| $	$ 23,900,000	$ 42,000,000.0
Allowance for doubtful accounts \| $	$ 18,000	$ 158,000
Revenue from rights, concentration risk \| Customer concentration risk \| Delta, United, and Continental Combined
Concentration Risk and Significant Customers
Concentration risk (as a percent)	77.60%	81.40%	82.90%
Full-time equivalent number of employees \| Labor force concentration risk
Concentration Risk and Significant Customers
Number of employees \| employee	13,700
SkyWest Airlines \| Full-time equivalent number of employees \| Unionized employees
Concentration Risk and Significant Customers
Approximate number of active employees \| employee	0