Defined Contribution Plan, Employer Discretionary Contribution Amount, Percentage

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- Definition

Defined Contribution Plan, Employer Discretionary Contribution Amount, Period Not In Force

+ References

No definition available.

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- Definition

Defined Contribution Plan, Employer Discretionary Contribution Amount, Service Period

+ References

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- Definition

Defined Contribution Plan, Employer Matching Contribution, Minimum Service Period

+ References

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- Definition

Defined Contribution Plan, Employers Matching Contribution, Vesting Period

+ References

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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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.

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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.

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Employee Retirement Plans - Frontier 401(k) and FAPA Plan (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended				28 Months Ended
	Apr. 30, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2018	Jan. 31, 2019
Defined Contribution Plan Disclosure [Line Items]
Expense related to matching contributions		$ 46	$ 37	$ 32
Frontier 401(k) Plan
Defined Contribution Plan Disclosure [Line Items]
Percent of match		50.00%
Minimum service period		1 year
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 Airlines, Inc. Pilots Retirement Plan
Defined Contribution Plan Disclosure [Line Items]
Percent of match		50.00%
Employer contribution, percent of employees' gross pay, initial percentage		10.00%
Annual vesting percentage		25.00%
Vesting period		4 years
Period following collective bargaining agreement							5 years
Frontier Airlines, Inc. Pilots Retirement Plan \| Three years of service
Defined Contribution Plan Disclosure [Line Items]
Nonelective contribution amount					0.00%
Nonelective contribution, service period					3 years
Frontier Airlines, Inc. Pilots Retirement Plan \| Seven years of service
Defined Contribution Plan Disclosure [Line Items]
Nonelective contribution amount					6.00%
Nonelective contribution, service period					7 years
Frontier Airlines, Inc. Pilots Retirement Plan \| Minimum
Defined Contribution Plan Disclosure [Line Items]
Nonelective contribution amount				12.00%
Frontier Airlines, Inc. Pilots Retirement Plan \| Maximum
Defined Contribution Plan Disclosure [Line Items]
Nonelective contribution amount				15.00%