Number of persons employed by the Entity

No definition available.

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- Definition

Represents the full-time equivalent number of the entity's employees as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Represents the approximate number of active employees in employee groups.

+ References

No definition available.

+ Details

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
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- Details

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- Details

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Commitments and Contingencies - Concentration Risks and Employees Under Collective Bargaining Agreements (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) employee	Dec. 31, 2017 USD ($)	Dec. 31, 2016
Concentration Risk and Significant Customers
Allowance for doubtful accounts \| $	$ 158,000	$ 157,000
Revenue from rights, concentration risk \| Customer concentration risk \| Delta, United, and Continental Combined
Concentration Risk and Significant Customers
Concentration risk (as a percent)	81.40%	82.90%	88.70%
Full-time equivalent number of employees \| Labor force concentration risk
Concentration Risk and Significant Customers
Number of employees	15,900
Full-time equivalent number of employees \| ExpressJet \| Unionized employees
Concentration Risk and Significant Customers
Number of full-time equivalent employees	2,932
Approximate number of active employees	2,320
SkyWest Airlines \| Full-time equivalent number of employees \| Unionized employees
Concentration Risk and Significant Customers
Approximate number of active employees	0