Debt Instrument, Basis Spread on Variable Rate Term

No definition available.

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- Definition

Debt Instrument, Liquidation Requirement, Interest Percentage

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Debt Instrument, Number Of Tranches

+ References

No definition available.

+ Details

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Namespace Prefix:	algt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number Of Aircraft, Finance Lease Obligation

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of excess of preference in liquidation over convertible debt instrument's if-converted par or stated value of share.

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Balance Type:	credit
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- Definition

Face (par) amount of debt instrument at time of issuance.

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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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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+ Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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The net cash inflow or outflow in aggregate debt due to repayments and proceeds from additional borrowings.

+ References

No definition available.

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- Definition

Amount of cash outflow for short-term and long-term debt. Excludes payment of lease obligation.

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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Long-Term Debt - Narrative (Detail) $ in Millions	1 Months Ended				3 Months Ended	4 Months Ended	6 Months Ended	12 Months Ended
Long-Term Debt - Narrative (Detail) $ in Millions	Dec. 31, 2025 USD ($) Aircraft	Dec. 31, 2024 USD ($)	Mar. 31, 2024 USD ($)	Aug. 31, 2022 USD ($)	Dec. 31, 2025 USD ($) Aircraft	Feb. 29, 2024 USD ($)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($) Aircraft	Apr. 30, 2025 USD ($)	Feb. 28, 2025 USD ($)	Nov. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Feb. 28, 2023 USD ($)	Oct. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity											$ 158.0
Repayments of Lines of Credit								$ 204.7
Number Of Aircraft, Finance Lease Obligation \| Aircraft	23				23			23
Proceeds from Issuance of Unsecured Debt		$ 130.5
Minimum
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.44%				4.44%			4.44%
Maximum
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.02%				7.02%			7.02%
Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 150.0		$ 218.5		$ 150.0			$ 150.0				$ 412.1
Long-Term Line of Credit	218.5				218.5			218.5
Repayments of Debt	50.8
Debt Instrument, Term			12 years
Revolving Credit Facility \| Credit Agricole Corporate and Investment Bank
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity													$ 100.0		$ 50.0
Senior Secured Revolving Loan Facility \| Barclays Bank PLC
Debt Instrument [Line Items]
Long-Term Line of Credit				$ 75.0
Line of credit facility, expiration period				57 months
Secured Debt
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity									$ 221.3
Long-Term Line of Credit	$ 221.3				$ 221.3			$ 221.3
Debt Instrument, Basis Spread on Variable Rate Term	3 months				3 months			3 months
Debt Instrument, Number Of Tranches \| Aircraft	2				2			2
Secured Debt \| Minimum
Debt Instrument [Line Items]
Debt Instrument, Term								7 years
Secured Debt \| Maximum
Debt Instrument [Line Items]
Debt Instrument, Term								12 years
Unsecured Credit Facility
Debt Instrument [Line Items]
Repayments of Lines of Credit					$ 130.5
Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Convertible, Liquidation Preference, Value				$ 300.0
Debt Instrument, Liquidation Requirement, Interest Percentage				0.020
Delayed-Draw Construction Loan \| Sunseeker Resort (1)
Debt Instrument [Line Items]
Debt Instrument, Face Amount														$ 350.0
Repayments of Lines of Credit							$ 250.0
Line of Credit, Current										$ 100.0
Senior Secured Notes Due 2027 \| Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 403.0			$ 550.0	$ 403.0			$ 403.0
Debt Instrument, Interest Rate, Stated Percentage				7.25%
Proceeds from (Repayments of) Debt								$ 147.0
Senior Secured Notes Due 2027 \| Senior Notes \| Maximum
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.25%				7.25%			7.25%
Financing Agreement
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 149.2				$ 149.2			$ 149.2
Debt Instrument, Basis Spread on Variable Rate Term	3 months				3 months			3 months
Debt Instrument, Term								12 years
Other Secured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Repayments of Lines of Credit								$ 132.6
Proceeds from Lines of Credit						$ 132.6
Debt Instrument, Unused Borrowing Capacity, Amount	$ 25.1				$ 25.1			$ 25.1