Defined Contribution Plan, Employer Discretionary Contribution Amount, Percentage

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- Definition

Defined Contribution Plan, Employers Matching Contribution, Eligibility Period

+ References

No definition available.

+ Details

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- Definition

Defined Contribution Plan, Employers Matching Contribution, Vesting Period

+ References

No definition available.

+ Details

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480794/715-70-50-1

+ 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

+ Details

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Employee Retirement Plans (Details) - USD ($) $ in Millions	12 Months Ended
Employee Retirement Plans (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Defined Contribution Plan Disclosure [Line Items]
Expense related to matching contributions	$ 71	$ 69	$ 65
Eligibility period	60 days
Frontier 401(k) Plan
Defined Contribution Plan Disclosure [Line Items]
Percent of match	50.00%
Annual vesting percentage	25.00%
Vesting period	4 years
Frontier 401(k) Plan \| Maintenance Employee
Defined Contribution Plan Disclosure [Line Items]
Employer contribution, percent of employees' gross pay, initial percentage	2.00%
Frontier 401(k) Plan \| All Employees Excluding Maintenance Employees
Defined Contribution Plan Disclosure [Line Items]
Employer contribution, percent of employees' gross pay, initial percentage	6.00%
Frontier 401(k) Plan \| Flight Attendant
Defined Contribution Plan Disclosure [Line Items]
Percent of match	100.00%
Employer contribution, percent of employees' gross pay, initial percentage	6.00%
Frontier 401(k) Plan \| Puerto Rico 401(k) Plan
Defined Contribution Plan Disclosure [Line Items]
Employer contribution, percent of employees' gross pay, initial percentage	6.00%
Frontier Airlines, Inc. Pilots Retirement Plan \| Minimum
Defined Contribution Plan Disclosure [Line Items]
Non-elective contribution amount	12.00%
Frontier Airlines, Inc. Pilots Retirement Plan \| Maximum
Defined Contribution Plan Disclosure [Line Items]
Non-elective contribution amount	15.00%