Special Charges and Credits	12 Months Ended
Dec. 31, 2012
Restructuring and Related Activities [Abstract]
Special Charges and Credits	Special Charges and Credits Slot Transaction In June 2012, the Company transferred four permanent air carrier slots at Ronald Reagan National Airport (“DCA”) to another airline ("buyer") for $9.1 million in cash, which the Company received in June. Due to FAA regulations, the buyer could not operate the slots until written confirmation of the slot transfer had been received from the FAA. In accordance with FAA's 80% “use or lose” requirements, the Company continued to operate all four slots through September 6, 2012. Due to the restriction preventing operating use of the slots by buyer, the gain of $9.1 million was fully deferred at the time of the sale. The Company recognized the $9.1 million gain within special charges (credits) in the third quarter of 2012, the period in which the FAA operating restriction lapsed and written confirmation of the slot transfer was received by the buyer from the FAA. Secondary Offering Costs On July 31, 2012, certain existing stockholders affiliated with Oaktree Capital Management ("Oaktree") sold an aggregate of 9,394,927 shares of common stock in an underwritten public offering. The Company incurred a total of $0.7 million in costs during the year ended December 31, 2012, related to this offering. Upon completion of this offering, investment funds affiliated with Oaktree owned no shares of common stock of Spirit Airlines. The Company did not receive any proceeds from this offering. Previously, on January 25, 2012, certain stockholders of the Company, including affiliates of Oaktree and Indigo Partners, LLC ("Indigo") and certain members of the Company's executive team, sold an aggregate of 12,650,000 shares of common stock in an underwritten public offering. The Company incurred a total of $1.3 million in costs between 2011 and 2012 related to this offering, of which $0.5 million were incurred during the year ended December 31, 2012, offset by reimbursements from certain selling shareholders of $0.6 million in accordance with the Fourth Amendment to the Second Amended and Restated Investor Rights Agreement. The Company did not receive any proceeds from this offering. Initial Public Offering Costs In June 2011, the Company issued and sold 15,600,000 shares of common stock in its initial public offering (IPO). The Company incurred contract termination costs and fees of $2.25 million in connection with the IPO during the year ended December 31, 2011, which included $1.8 million paid to Indigo to terminate its professional services agreement with the Company and $0.5 million paid to three individual, unaffiliated holders of the Company’s subordinated notes.

Special Charges and Credits

Slot Transaction

In June 2012, the Company transferred four permanent air carrier slots at Ronald Reagan National Airport (“DCA”) to another airline ("buyer") for $9.1 million in cash, which the Company received in June. Due to FAA regulations, the buyer could not operate the slots until written confirmation of the slot transfer had been received from the FAA. In accordance with FAA's 80% “use or lose” requirements, the Company continued to operate all four slots through September 6, 2012. Due to the restriction preventing operating use of the slots by buyer, the gain of $9.1 million was fully deferred at the time of the sale. The Company recognized the $9.1 million gain within special charges (credits) in the third quarter of 2012, the period in which the FAA operating restriction lapsed and written confirmation of the slot transfer was received by the buyer from the FAA.

Secondary Offering Costs

On July 31, 2012, certain existing stockholders affiliated with Oaktree Capital Management ("Oaktree") sold an aggregate of 9,394,927 shares of common stock in an underwritten public offering. The Company incurred a total of $0.7 million in costs during the year ended December 31, 2012, related to this offering. Upon completion of this offering, investment funds affiliated with Oaktree owned no shares of common stock of Spirit Airlines. The Company did not receive any proceeds from this offering.

Previously, on January 25, 2012, certain stockholders of the Company, including affiliates of Oaktree and Indigo Partners, LLC ("Indigo") and certain members of the Company's executive team, sold an aggregate of 12,650,000 shares of common stock in an underwritten public offering. The Company incurred a total of $1.3 million in costs between 2011 and 2012 related to this offering, of which $0.5 million were incurred during the year ended December 31, 2012, offset by reimbursements from certain selling shareholders of $0.6 million in accordance with the Fourth Amendment to the Second Amended and Restated Investor Rights Agreement. The Company did not receive any proceeds from this offering.

Initial Public Offering Costs

In June 2011, the Company issued and sold 15,600,000 shares of common stock in its initial public offering (IPO). The Company incurred contract termination costs and fees of $2.25 million in connection with the IPO during the year ended December 31, 2011, which included $1.8 million paid to Indigo to terminate its professional services agreement with the Company and $0.5 million paid to three individual, unaffiliated holders of the Company’s subordinated notes.