Accrued Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Federal excise and other passenger taxes and fees payable	$ 47,730	$ 42,628
Federal and state income tax payable	31,511us-gaap_AccruedIncomeTaxesCurrent	3,286us-gaap_AccruedIncomeTaxesCurrent
Salaries and wages	30,078	34,209
Airport expenses	24,162save_AccruedAirportExpensesCurrent	21,726save_AccruedAirportExpensesCurrent
Aircraft maintenance	17,508	16,127
Aircraft and facility rent	10,651us-gaap_AccruedRentCurrent	10,089us-gaap_AccruedRentCurrent
Fuel	8,937save_AccruedFuelCostsCurrent	9,508save_AccruedFuelCostsCurrent
Other	20,297us-gaap_OtherAccruedLiabilitiesCurrent	15,348us-gaap_OtherAccruedLiabilitiesCurrent
Other current liabilities	$ 190,874us-gaap_OtherLiabilitiesCurrent	$ 152,921us-gaap_OtherLiabilitiesCurrent

Accrued Aircraft Maintenance Expenses, Current

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- Definition

Accrued Airport Expenses, Current

+ References

No definition available.

+ Details

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- Definition

Accrued Fuel Costs, Current

+ References

No definition available.

+ Details

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- Definition

Federal Excise and Other Passenger Taxes and Fees Payable, Current

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

+ References

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for contractual rent under lease arrangements. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Current Liabilities

-URI http://asc.fasb.org/extlink&oid=6509677

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6935-107765

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6911-107765

+ Details

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- Definition

Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

+ Details

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- Definition

Aggregate carrying amount of current liabilities (due within one year or within the normal operating cycle if longer) not separately disclosed in the balance sheet. Includes costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered and of liabilities not separately disclosed.

+ References

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