Spirit Airlines (SAVEQ) 10-Q 22 Jul 20 2020 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Jun. 30, 2020	Jul. 15, 2020
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2020
Document Transition Report	false
Entity File Number	001-35186
Entity Registrant Name	SPIRIT AIRLINES, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	38-1747023
Entity Address, Address Line One	2800 Executive Way
Entity Address, City or Town	Miramar
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	33025
City Area Code	954
Local Phone Number	447-7920
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		88,671,536
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001498710
Current Fiscal Year End Date	--12-31
Common Stock, $0.0001 par value
Document Information [Line Items]
Title of 12(b) Security	Common Stock, $0.0001 par value
Security Exchange Name	NYSE
Trading Symbol	SAVE
Series A Preferred Stock Purchase Rights
Document Information [Line Items]
Title of 12(b) Security	Series A Preferred Stock Purchase Rights
Security Exchange Name	NYSE
Trading Symbol	SAVE

Condensed Statements of Operati

Condensed Statements of Operations (unaudited) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating revenues:
Revenues	$ 138,529,000	$ 1,012,956,000	$ 909,610,000	$ 1,868,752,000
Operating expenses:
Aircraft fuel	19,910,000	265,006,000	233,118,000	494,642,000
Salaries, wages and benefits	213,579,000	216,375,000	454,059,000	420,276,000
Landing fees and other rents	40,348,000	64,711,000	107,469,000	124,360,000
Depreciation and amortization	69,113,000	54,913,000	135,104,000	105,639,000
Aircraft rent	49,256,000	46,522,000	94,402,000	92,304,000
Distribution	11,352,000	40,602,000	45,095,000	76,321,000
Maintenance, materials and repairs	19,227,000	34,688,000	53,303,000	66,292,000
Loss on disposal of assets	0	1,550,000	0	3,463,000
Special credits	(151,911,000)	0	(151,911,000)	0
Other operating	58,039,000	124,651,000	187,347,000	233,713,000
Total operating expenses	328,913,000	849,018,000	1,157,986,000	1,617,010,000
Operating income (loss)	(190,384,000)	163,938,000	(248,376,000)	251,742,000
Other (income) expense:
Interest expense	27,792,000	25,266,000	51,670,000	50,237,000
Capitalized interest	(3,757,000)	(2,975,000)	(7,421,000)	(5,532,000)
Interest income	(1,949,000)	(7,066,000)	(5,542,000)	(13,990,000)
Other (income) expense	66,000	144,000	47,000	377,000
Total other (income) expense	22,152,000	15,369,000	38,754,000	31,092,000
Income (loss) before income taxes	(212,536,000)	148,569,000	(287,130,000)	220,650,000
Provision (benefit) for income taxes	(68,108,000)	34,068,000	(114,874,000)	50,073,000
Net income (loss)	$ (144,428,000)	$ 114,501,000	$ (172,256,000)	$ 170,577,000
Basic earnings (loss) per share (in dollars per share)	$ (1.81)	$ 1.67	$ (2.33)	$ 2.49
Diluted earnings (loss) per share (in dollars per share)	$ (1.81)	$ 1.67	$ (2.33)	$ 2.49
Passenger
Operating revenues:
Revenues	$ 130,817,000	$ 994,430,000	$ 884,367,000	$ 1,832,495,000
Other
Operating revenues:
Revenues	$ 7,712,000	$ 18,526,000	$ 25,243,000	$ 36,257,000

Condensed Statements of Compreh

Condensed Statements of Comprehensive Income (Loss) (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (144,428)	$ 114,501	$ (172,256)	$ 170,577
Unrealized gain on short-term investment securities and cash and cash equivalents, net of deferred taxes of $5, $29, $59 and $67	18	98	203	228
Interest rate derivative loss reclassified into earnings, net of taxes of $15, $19, $39 and $46	48	54	89	101
Other comprehensive income	66	152	292	329
Comprehensive income (loss)	$ (144,362)	$ 114,653	$ (171,964)	$ 170,906

Condensed Statements of Compr_2

Condensed Statements of Comprehensive Income (Parenthetical) (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Tax effect of the unrealized gain on short-term investment securities and cash and cash equivalents	$ 5	$ 29	$ 59	$ 67
Interest rate derivative loss reclassified into earnings, tax	$ 15	$ 19	$ 39	$ 46

Condensed Balance Sheets (unaud

Condensed Balance Sheets (unaudited) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 1,127,460	$ 978,957
Restricted cash	30,000	0
Short-term investment securities	106,298	105,321
Accounts receivable, net	56,043	73,807
Aircraft maintenance deposits, net	75,147	102,906
Income tax receivable	146,961	21,013
Prepaid expenses and other current assets	126,051	103,439
Total current assets	1,667,960	1,385,443
Property and equipment:
Flight equipment	4,071,980	3,730,751
Ground property and equipment	320,526	291,998
Less accumulated depreciation	(582,098)	(492,447)
Total property and equipment, net	3,810,408	3,530,302
Operating lease right-of-use assets	1,430,897	1,369,555
Pre-delivery deposits on flight equipment	382,652	291,930
Long-term aircraft maintenance deposits	63,623	67,682
Deferred heavy maintenance, net	376,745	361,603
Other long-term assets	35,659	36,897
Total assets	7,767,944	7,043,412
Current liabilities:
Accounts payable	41,060	43,601
Air traffic liability	452,023	315,408
Current maturities of long-term debt and finance leases	288,498	258,852
Current maturities of operating leases	128,536	120,662
Deferred salaries, wages and benefits	114,052	0
Other current liabilities	247,013	373,521
Total current liabilities	1,271,182	1,112,044
Long-term debt and finance leases, less current maturities	2,333,600	1,960,453
Operating leases, less current maturities	1,269,670	1,218,014
Deferred income taxes	517,537	469,292
Deferred gains and other long-term liabilities	32,793	22,277
Shareholders’ equity:
Common stock	27	7
Additional paid-in-capital	636,317	379,380
Treasury stock, at cost	(74,009)	(72,455)
Retained earnings	1,781,322	1,955,187
Accumulated other comprehensive income (loss)	(495)	(787)
Total shareholders’ equity	2,343,162	2,261,332
Total liabilities and shareholders’ equity	$ 7,767,944	$ 7,043,412

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows (unaudited) - USD ($)		3 Months Ended				6 Months Ended		9 Months Ended
		Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2019
Operating activities:
Net income (loss)		$ (144,428,000)	$ (27,828,000)	$ 114,501,000	$ 56,076,000	$ (172,256,000)	$ 170,577,000
Adjustments to reconcile net income (loss) to net cash provided by operations:
Losses reclassified from other comprehensive income						128,000	148,000
Share-based compensation						6,442,000	6,413,000
Allowance for doubtful accounts (recoveries)						(226,000)	0
Amortization of deferred gains, losses and debt issuance costs						4,633,000	4,365,000
Depreciation and amortization		69,113,000		54,913,000		135,104,000	105,639,000	$ 105,639,000
Accretion of convertible debt						2,029,000	0
Deferred income tax expense						31,518,000	44,511,000
Loss on disposal of assets		0		1,550,000		0	3,463,000
Changes in operating assets and liabilities:
Accounts receivable, net						17,360,000	(30,465,000)
Aircraft maintenance deposits, net						11,254,000	(6,214,000)
Prepaid income taxes						0	1,962,000
Long-term deposits and other assets						(16,717,000)	10,212,000
Deferred heavy maintenance						(57,306,000)	(88,350,000)
Income tax receivable						(125,948,000)	0
Accounts payable						(6,477,000)	2,024,000
Air traffic liability						136,615,000	111,009,000
Deferred salaries, wages and benefits, net						114,052,000	0
Other liabilities						(127,204,000)	6,154,000
Other						40,000	(424,000)
Net cash provided (used) by operating activities						(46,959,000)	341,024,000
Investing activities:
Purchase of available-for-sale investment securities						(54,992,000)	(57,355,000)
Proceeds from the maturity and sale of available-for-sale investment securities						54,195,000	56,595,000
Pre-delivery deposits on flight equipment, net of refunds						(153,353,000)	(75,826,000)
Capitalized interest						(6,289,000)	(4,936,000)
Assets under construction for others						(2,282,000)	(2,235,000)
Purchase of property and equipment						(294,633,000)	(154,702,000)
Net cash used in investing activities						(457,354,000)	(238,459,000)
Financing activities:
Proceeds from issuance of long-term debt						674,146,000	94,706,000
Proceeds from issuance of common stock and warrants						203,723,000	0
Proceeds from stock options exercised						39,000	1,000
Payments on debt obligations						(149,429,000)	(85,785,000)
Payments on finance lease obligations						(25,020,000)	(1,796,000)
Reimbursement for assets under construction for others						2,322,000	2,235,000
Repurchase of common stock						(1,554,000)	(5,248,000)
Long-term debt and equity issuance costs						(21,411,000)	(614,000)
Net cash provided by financing activities						682,816,000	3,499,000
Net increase (decrease) in cash, cash equivalents, and restricted cash						178,503,000	106,064,000
Cash and cash equivalents at beginning of period			$ 978,957,000		$ 1,004,733,000	978,957,000	1,004,733,000	$ 1,004,733,000
Cash, cash equivalents, and restricted cash at end of period (1)	[1]	$ 1,157,460,000		$ 1,110,797,000		1,157,460,000	1,110,797,000
Cash payments for:
Interest, net of capitalized interest						37,636,000	41,279,000
Income taxes paid (received), net						(19,631,000)	7,394,000
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows for operating leases						103,127,000	95,643,000
Financing cash flows for finance leases						139,000	339,000
Non-cash transactions:
Capital expenditures funded by finance lease borrowings						565,000	96,371,000
Capital expenditures funded by operating lease borrowings						$ 120,961,000	$ 159,548,000
[1]	(1) The sum of cash and cash equivalents and restricted cash on our condensed balance sheets equals cash, cash equivalents, and restricted cash in our statement of cash flows.

Condensed Statements of Shareho

Condensed Statements of Shareholders' Equity Statement - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid-In-Capital	Treasury Stock	Retained Earnings	Retained EarningsCumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2018	$ 1,928,504	$ (5,549)	$ 7	$ 371,225	$ (67,016)	$ 1,625,481	$ (5,549)	$ (1,193)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation	3,671			3,671
Repurchase of common stock	(5,223)				(5,223)
Proceeds from options exercised	0
Changes in comprehensive income	177							177
Net income (loss)	56,076					56,076
Ending balance at Mar. 31, 2019	1,977,656		7	374,896	(72,239)	1,676,008		(1,016)
Beginning balance at Dec. 31, 2018	1,928,504	(5,549)	7	371,225	(67,016)	1,625,481	(5,549)	(1,193)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Changes in comprehensive income	329
Net income (loss)	170,577
Ending balance at Jun. 30, 2019	$ 2,095,027		7	377,639	(72,264)	1,790,509		(864)
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Beginning balance at Dec. 31, 2018	$ 1,928,504	(5,549)	7	371,225	(67,016)	1,625,481	(5,549)	(1,193)
Ending balance at Dec. 31, 2019	2,261,332	(1,609)	7	379,380	(72,455)	1,955,187	(1,609)	(787)
Beginning balance at Mar. 31, 2019	1,977,656		7	374,896	(72,239)	1,676,008		(1,016)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation	2,742			2,742
Repurchase of common stock	(25)				(25)
Proceeds from options exercised	1			1
Changes in comprehensive income	152							152
Net income (loss)	114,501					114,501
Ending balance at Jun. 30, 2019	2,095,027		7	377,639	(72,264)	1,790,509		(864)
Beginning balance at Dec. 31, 2019	2,261,332	(1,609)	7	379,380	(72,455)	1,955,187	(1,609)	(787)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation	3,790			3,790
Repurchase of common stock	(1,536)				(1,536)
Proceeds from options exercised	16			16
Changes in comprehensive income	226							226
Net income (loss)	(27,828)					(27,828)
Ending balance at Mar. 31, 2020	$ 2,234,391		7	383,186	(73,991)	1,925,750		(561)
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Beginning balance at Dec. 31, 2019	$ 2,261,332	$ (1,609)	7	379,380	(72,455)	1,955,187	$ (1,609)	(787)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Changes in comprehensive income	292
Net income (loss)	(172,256)
Ending balance at Jun. 30, 2020	2,343,162		27	636,317	(74,009)	1,781,322		(495)
Beginning balance at Mar. 31, 2020	2,234,391		7	383,186	(73,991)	1,925,750		(561)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock and warrants, net	194,886		20	194,866
Equity component value of convertible debt issuance, net	55,590			55,590
Share-based compensation	2,652			2,652
Repurchase of common stock	(18)				(18)
Proceeds from options exercised	23			23
Changes in comprehensive income	66							66
Net income (loss)	(144,428)					(144,428)
Ending balance at Jun. 30, 2020	$ 2,343,162		$ 27	$ 636,317	$ (74,009)	$ 1,781,322		$ (495)

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed financial statements include the accounts of Spirit Airlines, Inc. (the "Company"). These unaudited condensed financial statements reflect all normal recurring adjustments which management believes are necessary to fairly present the financial position, results of operations and cash flows of the Company for the respective periods presented. Certain information and footnote disclosures normally included in the audited annual financial statements prepared in accordance with U.S. generally accepted accounting principles ("GAAP") have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission for Form 10-Q. These unaudited interim condensed financial statements should be read in conjunction with the audited financial statements of the Company and notes thereto included in the Company's Annual Report on Form 10-K/A for the year ended December 31, 2019 filed with the Securities and Exchange Commission on April 16, 2020. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect both the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from these estimates. The interim results reflected in the unaudited condensed financial statements are not necessarily indicative of the results that may be expected for other interim periods or for the full year. The air transportation business is subject to significant seasonal fluctuations as demand is generally greater in the second and third quarters of each year. The air transportation business is also volatile and highly affected by economic cycles and trends. In addition, the Company experienced significant impacts from the global coronavirus ("COVID-19") pandemic during the three and six months ended June 30, 2020.

Impact of COVID-19

Impact of COVID-19	6 Months Ended
	Jun. 30, 2020
Unusual or Infrequent Items, or Both [Abstract]
Impact of COVID-19	Impact of COVID-19 As the COVID-19 pandemic continues to evolve, the Company's financial and operational outlook remains subject to change. The Company continues to monitor the impacts of the pandemic on its operations and financial condition, and to implement mitigation strategies while working to preserve cash and protect the long-term sustainability of the Company. The Company has implemented measures for the safety of its Guests and Team Members as well as to mitigate the impact of COVID-19 on its financial position and operations. Caring for Guests and Team Members The Company’s Operations and Task Force teams remain in constant contact with authorities, continuing to evolve its response to ensure the safety of Guests and Team Members. In addition to previously existing procedures including utilization of hospital-grade disinfectants and state-of-the-art HEPA filters that capture 99.97% of airborne particles on board the aircraft, the Company has implemented the following steps to protect its Guests and Team Members: • Secured and distributed additional supplies of gloves and sanitizer across the Company's network and augmented the contents of onboard supply kits to contain additional cleaning and sanitizing materials; • Secured and provided face coverings for all crew and Guest facing team members; • Expanded cleaning protocols at airports and other facilities, including the use of EPA-registered disinfectants in all check-in and gate areas and the use of electrostatic sprayers at high-traffic airports; • Expanded aircraft turn and overnight cleaning protocols focusing on high frequency touch points as well as enhanced cockpit cleaning and the use of ultra-low volume ("ULV") fogging process to apply a safe, high grade- EPA-registered airborne disinfectant that is effective against coronaviruses; • Launched a new antimicrobial fogging tool in our facilities and aircraft that uses a product that forms an invisible barrier on all surfaces killing bacteria and viruses on contact for 30 days; • Split the Company's Operational Control Center ("OCC") into multiple units to enable social distancing and prepared the OCC to work remotely to minimize potential operational disruption; • Implemented a remote work policy for the Support Center teams to maintain support of the Company's operations; • Required all Guests and Guest-facing Team Members to wear an appropriate face covering when traveling through the airport or onboard aircraft; • Offered future flight credits with extended expiration dates to Guests with impacted travel plans and waived change and cancellation fees for Guests who booked travel by July 31, 2020. Supporting Communities During this unprecedented time, many travelers became stranded abroad when bans and other restrictions on travel were implemented globally and domestically with little notice. The Company has worked with embassies and local governments in Aruba, Colombia, Dominican Republic, Ecuador, Haiti, Honduras, Panama and the U.S. to operate special flights for stranded travelers in such countries. Thus far, the Company has provided over 140 flights to more than 18,000 stranded travelers and preparations continue to transport many more. In addition, the Company has pledged $250 thousand in vouchers for flights to minority organizations. The Company has also made efforts to address the growing needs of its communities through The Spirit Airlines Charitable Foundation (the “Foundation”). As part of the its focus on supporting families, the Foundation partnered with other non-profit organizations including the YMCA and Jack and Jill Children’s Center to provide food to seniors and families struggling during this time and supported organizations creating face coverings for healthcare workers. In addition, the Company has partnered to offer Guests face coverings for a small contribution to the Red Cross. Capacity Reductions In March 2020, in response to government restrictions on travel and drastically reduced consumer demand, the Company began to reduce capacity. The Company reduced capacity for April 2020 by 76.2%, year over year and May 2020 capacity was reduced by 93.9%, year over year. The Company had initially expected to reduce June 2020 capacity by approximately 95%, year over year. However, due to an increase in demand for air travel, the Company added some flights back to the June schedule, building throughout the month, resulting in an average capacity reduction of 79.0%, year over year. Capacity in July, August and September of 2020 has been reduced by approximately 18%, 35% and 45% respectively, year over year. The Company continues to closely monitor demand and will make adjustments to the flight schedule as appropriate. The Company currently estimates that air travel demand recovery will be volatile and will fluctuate in the upcoming months as the lingering effects of COVID-19 continue to emerge. The Company expects that air travel demand will continue to gradually recover in the second half of 2020 through 2021. However, the situation continues to be fluid and actual capacity adjustments may be different than what the Company currently expects. Refer to Note 4, Revenue, for discussion of the impact of COVID-19 on the Company's air traffic liability, credit shells and refunds. CARES Act On March 27, 2020, President Donald Trump signed the Coronavirus Aid, Relief, and Economic Security Act ("CARES Act") into law. The CARES Act is a relief package intended to assist many aspects of the American economy, including providing the airline industry with up to $25 billion in grants to be used for employee salaries, wages and benefits and up to$25.0 billion in secured loans. On April 20, 2020, the Company entered into a Payroll Support Program Agreement ("PSP") with the United States Department of the Treasury ("Treasury"), pursuant to which the Company expects to receive a total of $334.7 million, to be used exclusively to pay for salaries, wages and benefits for the Company’s Team Members through September 30, 2020. Of that amount, $70.4 million is in the form of a low-interest 10-year loan. In addition, in connection with its participation in the PSP, the Company is obligated to issue to Treasury warrants pursuant to a warrant agreement to purchase up to 500,150 shares of the Company’s common stock at a strike price of $14.08 per share (the closing price for the shares of the Company's common stock on April 9, 2020). As of June 30, 2020, the Company received total proceeds of $301.3 million, representing 3 of the 4 installments of funding under the PSP, in exchange for which the Company issued to Treasury $60.4 million in 10-year notes and warrants to purchase 428,829 shares of common stock valued and recorded at $2.5 million in additional paid-in-capital ("APIC") and $238.4 million in deferred salaries, wages and benefits within the Company's condensed balance sheets. Refer to Note 13, Debt and Other Obligations, for additional information on the notes issued and Note 14, Equity, for additional information on the warrants. The Company expects to receive the remaining proceeds of $33.4 million with the fourth and final installment of the PSP on or around July 31, 2020, in exchange for an additional $10.0 million in 10-year notes and warrants to purchase an additional 71,321 shares of common stock to be issued to the Treasury. The warrants issued represent less than 1% of the outstanding shares of the Company's common stock as of July 15, 2020. During the three and six months ended June 30, 2020, the Company recognized $123.9 million of deferred salaries, wages and benefits within special credits on the Company’s condensed statements of operations. Refer to Note 6, Special Credits, for additional information. In connection with the Company’s receipt of funds under the PSP, the Company is subject to certain restrictions, including, but not limited to: • Restrictions on payment of dividends and stock buybacks through September 30, 2021; • Requirements to maintain certain levels of scheduled service through September 30, 2020; • A prohibition on involuntary terminations or furloughs of the Company's employees (except for health, disability, cause, or certain disciplinary reasons) through September 30, 2020; • A prohibition on reducing the salary, wages, or benefits of the Company's employees (other than the Company's executive officers or independent contractors, or as otherwise permitted under the terms of the PSP) through September 30, 2020; • Limits on certain executive compensation, including limiting pay increases and severance pay or other benefits upon terminations, through March 24, 2022; • Use of the grant funds exclusively for the continuation of payment of employee wages, salaries and benefits and; • The Company is subject to additional reporting and recordkeeping requirements relating to the CARES Act funds. On April 29, 2020, the Company applied for additional funds under the Treasury's loan program under the CARES Act (“Loan Program”). The expected maximum availability to the Company under the Loan Program is approximately $741 million in the form of a secured loan. However, the loan amount is dependent on the amount and types of collateral accepted, which may result in an actual loan less than $741 million, if the Company accepts the loan. Any loan received pursuant to the Loan Program would be subject to the restrictions and relevant provisions of the CARES Act, including many of those noted above for the PSP. The Company’s participation in the Loan Program could materially increase the funds available to the Company as it works through the operational and business issues related to the COVID-19 pandemic and provide a base of available funding that could encourage private market transactions. On July 1, 2020, the Company executed a non-binding letter of intent with the Treasury which summarizes the principal terms of the financing request submitted by the Company to the Treasury. The Company continues to negotiate the terms of a definitive financing agreement under the Loan Program with the Treasury. In addition, subject to such negotiations, the Company will continue to evaluate its future cash flow needs and will determine whether or not to accept any or all of the funds available from the Loan Program. The deadline to make the election under the Loan Program is September 30, 2020. The CARES Act also provides an employee retention credit (“CARES Employee Retention credit”) which is a refundable tax credit against certain employment taxes of up to $5,000 per employee for eligible employers. The credit is equal to 50% of qualified wages paid to employees during a quarter, capped at $10,000 of qualified wages through year end. The Company qualified for the credit beginning on April 1, 2020 and expects to continue to receive additional credits for qualified wages through December 31, 2020. During the three and six months ended June 30, 2020, the Company recorded $28.0 million related to the CARES Employee Retention credit within special credits on the Company’s condensed statements of operations and within accounts receivable, net on the Company's condensed balance sheet. The Company expects to record an additional approximately $10 million in CARES Employee Retention credits in the remainder of 2020. Refer to Note 6, Special Credits, for additional information. The CARES Act also provides for certain tax loss carrybacks and a waiver on federal fuel taxes through December 31, 2020. As of June 30, 2020 , the Company had recognized $140.8 million in related tax loss carrybacks and $0.8 million in federal fuel tax savings reflected within fuel in the Company’s statements of operations. The Company expects to recognize an additional $5 million in savings related to the waiver on federal fuel taxes in the remainder of 2020. Finally, the CARES Act also provides for deferred payment of the employer portion of social security taxes through the end of 2020, with 50% of the deferred amount due December 31, 2021 and the remaining 50% due December 31, 2022. This is expected to provide the Company with approximately $24 million of additional liquidity during the current year. As of June 30, 2020, the Company has deferred $10.0 million in social security tax payments. The deferred amounts are recorded as a liability within other current liabilities on the Company’s condensed balance sheet. Income Taxes The Company's effective tax rate for the six months ended June 30, 2020 was 40.0% compared to 22.7% for the six months ended June 30, 2019. The increase in tax rate, as compared to the prior year period, is primarily due to a $54.9 million discrete federal tax benefit recorded during the six months ended June 30, 2020 related to the passage of the CARES Act. The CARES Act allows for carryback of net operating losses generated at a 21% tax rate to recover taxes paid at a 35% tax rate. Excluding this discrete tax benefit, the Company's effective tax rate for the six months ended June 30, 2020 would have been 20.9%. While the Company expects its tax rate to be fairly consistent in the near term, it will tend to vary depending on recurring items such as the amount of income we earn in each state and the state tax rate applicable to such income. Discrete items particular to a given year may also affect our effective tax rates. Balance Sheet, Cash Flow and Liquidity Since the onset of the spread of COVID-19 in the U.S. in the first quarter of 2020, the Company has taken several actions to increase liquidity and strengthen its financial position. As a result of these actions, as of June 30, 2020, the Company had unrestricted cash and cash equivalents and short-term investment securities of $1,233.8 million. In March 2020, the Company entered into a senior secured revolving credit facility (the "2022 revolving credit facility") for an initial commitment amount of $110.0 million, and subsequently, in the second quarter of 2020, increased its commitment amount to $180.0 million. As of June 30, 2020, the Company had fully drawn the available amount of $180.0 million under the 2022 revolving credit facility. The 2022 revolving credit facility matures on March 30, 2022. The Company continues to pursue additional financing secured by its unencumbered assets. Refer to Note 13, Debt and Other Obligations, for additional information about the 2022 revolving credit facility. On May 12, 2020, the Company completed the public offering of $175.0 million aggregate principal amount of 4.75% convertible senior notes due 2025 (the “convertible notes”). The convertible notes will bear interest at the rate of 4.75% per year and will mature on May 15, 2025. Interest on the convertible notes is payable semi-annually in arrears on May 15 and November 15 of each year, beginning on Nove mber 15, 2020. The Company received proceeds of $168.3 million, net of total issuance costs of $6.7 million and recorded $95.6 million in long-term debt, net of debt issuance costs of $3.8 million on its condensed balance sheets, related to the debt component of the convertible notes, and $72.7 million in APIC, net of issuance costs of $2.9 million on its condensed balance sheets, related to the equity component of the convertible notes. Refer to Note 13, Debt and Other Obligations for additional information about the Company’s convertible debt. Also on May 12, 2020, the Company completed the public offering of 20,125,000 shares of its voting common stock, which includes full exercise of the underwriters’ option to purchase an additional 2,625,000 shares of common stock, at a public offering price of $10.00 per share (the “common stock offering”). The Company received proceeds of $192.4 million , net of issuance costs of $8.9 million . Refer to Note 14, Equity, for further information about the Company’s common stock offering. In June 2020, the Company entered into an agreement to amend its revolving credit facility entered into in 2018 to finance aircraft pre-delivery payments. The agreement amends the revolving credit facility to extend the final maturity date from December 30, 2020 to March 31, 2021. Upon execution of the amended agreement, the maximum borrowing capacity decreased from $160.0 million to $111.2 million and during the six months ended June 30, 2020 we made net principal payments of $48.8 million. This facility is secured by the collateral assignment of certain of the Company’s rights under the purchase agreement with Airbus, related to 20 Airbus A320neo aircraft scheduled to be delivered between August 2020 and October 2022. The initial maximum borrowing capacity of $111.2 million will continue to decrease as the Company takes delivery of the related aircraft. The amendment will provide an additional approximately $54 million in liquidity through March 2021. Refer to Note 13, Debt and Other Obligations, for further information. Also, in June 2020, the Company entered into an agreement to defer certain aircraft deliveries originally scheduled in 2020 and 2021, as well as the related pre-delivery deposit payments. During the six months ended June 30, 2020, the Company took delivery of 9 aircraft and with this agreement, the Company has 3 remaining aircraft scheduled for delivery during the remainder of 2020 and 16 aircraft scheduled for delivery in 2021. Refer to Note 11, Commitments and Contingencies, for further information about the Company’s future aircraft deliveries. In addition, since the onset of the COVID-19 pandemic, the Company has taken additional action, including: • Reduced planned discretionary non-aircraft capital spend in 2020 by approximately $50 million; • Deferred $20 million in heavy maintenance events from 2020 to 2021; • Reduced planned non-fuel operating costs for 2020 by $20 million to $30 million, excluding savings related to reduced capacity; • Suspended hiring across the Company except to fill essential roles; • Entered into agreements to defer payments in 2020 related to facility rents and other airport services contracts at certain locations; • Continued to work with lessors and service providers to temporarily defer aircraft rent and other maintenance and service contract payments; • Continued to work with unionized and non-unionized employees to create voluntary leave programs; • Continued to pursue additional financing secured by its unencumbered assets. The Company continues to engage in discussions with the Company's significant stakeholders and vendors regarding financial support or contract adjustments, including extensions of payment terms, during this transition period. For purposes of assessing its liquidity needs, the Company estimates that demand will continue to improve slightly in the second half of 2020, but remain well below 2019 levels, and continue to recover into 2021. The Company believes the actions described above address its future liquidity needs, yet anticipates it may implement further discretionary changes and other cost reduction and liquidity preservation measures, as needed, to address the volatility and quickly changing dynamics of passenger demand and the impact of revenue changes, regulatory and public health directives and prevailing government policy and financial market conditions.

Recent Accounting Developments

Recent Accounting Developments	6 Months Ended
	Jun. 30, 2020
Accounting Standards Update and Change in Accounting Principle [Abstract]
Recent Accounting Developments	Recent Accounting Developments Recently Adopted Accounting Pronouncements Accounting for Credit Losses In June 2016, the FASB issued ASU No. 2016-13 Cloud Computing Arrangements

Revenue

Revenue	6 Months Ended
	Jun. 30, 2020
Revenue from Contract with Customer [Abstract]
Revenue	Revenue Operating revenues is comprised of passenger revenues, which includes fare and non-fare revenues, and other revenues. The following table shows disaggregated operating revenues for the three and six months ended June 30, 2020 and June 30, 2019. Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands) Operating revenues: Fare $ 63,769 $ 515,696 $ 385,216 $ 932,041 Non-fare 67,048 478,734 499,151 900,454 Total passenger revenues 130,817 994,430 884,367 1,832,495 Other 7,712 18,526 25,243 36,257 Total operating revenues $ 138,529 $ 1,012,956 $ 909,610 $ 1,868,752 The Company is managed as a single business unit that provides air transportation for passengers. Operating revenues by geographic region as defined by the Department of Transportation ("DOT") are summarized below: Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands) DOT—Domestic $ 134,373 $ 890,388 $ 832,293 $ 1,644,502 DOT—Latin America 4,156 122,568 77,317 224,250 Total $ 138,529 $ 1,012,956 $ 909,610 $ 1,868,752 The Company defers the amount for award travel obligation as part of loyalty deferred revenue within air traffic liability ("ATL") on the Company's condensed balance sheets and recognizes loyalty travel awards in passenger revenues as the mileage credits are used for travel or expire unused. As a result of the COVID-19 pandemic, the Company experienced significantly increased customer requests for credit shells, or customer travel funds held by the Company that can be redeemed for future travel, and refunds beginning in the second half of March 2020 and continuing through the second quarter of 2020 primarily due to flight cancellations. The total value of refunds issued during the three and six months ended June 30, 2020 were $77.4 million and $121.0 million, respectively. The Company expects that the level of requests for credit shells and refunds in the upcoming months will continue to fluctuate and vary as the effects of COVID-19 continue to emerge. In addition, in response to COVID-19, the Company increased the expiration period on some of its credit shells from 60 days to 12 months and waived change and cancellation fees for the Guests who booked travel by July 31, 2020. As a result, the outstanding balance of the unused credit shells (which is recorded within ATL on the Company's condensed balance sheets), as of June 30, 2020, significantly exceeds the balance in the prior year period. As of June 30, 2020 and December 31, 2019, the Company had ATL balances of $452.0 million and $315.4 million, respectively. The balance of the Company's ATL, including the balance of credit shells, is expected to be recognized within 12 months of the respective balance sheet date. Refer to Note 2, Impact of COVID-19, for further information on COVID-19's impact to the Company.

Loss on Disposal of Assets

Loss on Disposal of Assets	6 Months Ended
	Jun. 30, 2020
Discontinued Operations and Disposal Groups [Abstract]
Loss on Disposal of Assets	Loss on Disposal of AssetsDuring the three and six months ended June 30, 2020, the Company had no loss on disposal of assets in the condensed statement of operations. During the three and six months ended June 30, 2019, the Company recorded $1.6 million and $3.5 million in loss on disposal of assets in the condensed statement of operations. These amounts primarily related to the disposal of excess and obsolete inventory.

Special Credits

Special Credits	6 Months Ended
	Jun. 30, 2020
Special Credits [Abstract]
Special Credits	Special Credits During the second quarter of 2020, the Company recorded $237.9 million , net of issuance costs of $0.5 million , related to the grant component of the PSP with the Treasury within deferred salaries, wages and benefits on the Company's condensed balance sheets. The funds are to be used exclusively to pay for salaries, wages and benefits for the Company's Team Members through September 30, 2020. During the three and six months ended June 30, 2020, the Company recognized $123.9 million of the deferred salaries, wages and benefits within special credits on the Company’s condensed statements of operations. In addition, during the three and six months ended June 30, 2020, the Company recorded $28.0 million related to the CARES Act Employee Retention credit within special credits on the Company’s condensed statements of operation. Refer to Note 2, Impact of COVID-19, for further information on the CARES Act. During the three and six months ended June 30, 2019, the Company had no special credits in the condensed statement of operations.

Earnings (Loss) per Share

Earnings (Loss) per Share	6 Months Ended
	Jun. 30, 2020
Earnings Per Share [Abstract]
Earnings (Loss) per Share	Earnings (Loss) per Share The following table sets forth the computation of basic and diluted earnings (loss) per common share: Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands, except per share amounts) Numerator Net income (loss) $ (144,428) $ 114,501 $ (172,256) $ 170,577 Denominator Weighted-average shares outstanding, basic 79,601 68,439 74,061 68,410 Effect of dilutive stock awards — 181 — 158 Adjusted weighted-average shares outstanding, diluted 79,601 68,620 74,061 68,568 Earnings (loss) per share Basic earnings (loss) per common share $ (1.81) $ 1.67 $ (2.33) $ 2.49 Diluted earnings (loss) per common share $ (1.81) $ 1.67 $ (2.33) $ 2.49 Anti-dilutive weighted-average shares 565 127 524 143

Short-term Investment Securitie

Short-term Investment Securities	6 Months Ended
	Jun. 30, 2020
Investments, Debt and Equity Securities [Abstract]
Short-term Investment Securities	Short-term Investment SecuritiesThe Company's short-term investment securities are classified as available-for-sale and generally consist of U.S. Treasury and U.S. government agency securities with contractual maturities of 12 months or less. These securities are stated at fair value within current assets on the Company's condensed balance sheets. Realized gains and losses on sales of investments, if any, are reflected in non-operating income (expense) in the condensed statements of operations. As of June 30, 2020 and December 31, 2019, the Company had $106.3 million and $105.3 million in short-term available-for-sale investment securities, respectively. During the six months ended June 30, 2020, these investments earned interest income at a weighted-average fixed rate of approximately 1.5%. For the three and six months ended June 30, 2020, an unrealized loss and an unrealized gain of $199 thousand and $123 thousand, respectively, net of deferred taxes of $59 thousand and $36 thousand, respectively, was recorded within accumulated other comprehensive income ("AOCI") related to these investment securities. For the three and six months ended June 30, 2019, an unrealized gain of $98 thousand and $228 thousand, respectively, net of deferred taxes of $29 thousand and $67 thousand, respectively, was recorded within AOCI related to these investment securities. For the three and six months ended June 30, 2020, the Company had substantially no realized gains or losses related to these securities. For the three and six months ended June 30, 2019, the Company had no realized gains or losses as the Company did not sell any of these securities during these periods. As of June 30, 2020 and December 31, 2019, $227 thousand and $104 thousand, net of tax, respectively, remained in AOCI, related to these instruments.

Accrued Liabilities

Accrued Liabilities	6 Months Ended
	Jun. 30, 2020
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued Liabilities Other current liabilities as of June 30, 2020 and December 31, 2019 consist of the following: June 30, 2020 December 31, 2019 (in thousands) Salaries, wages and benefits $ 92,056 $ 89,163 Airport obligations 37,309 80,134 Federal excise and other passenger taxes and fees payable 22,947 65,312 Aircraft maintenance 21,615 38,099 Aircraft and facility lease obligations 21,163 20,656 Interest payable 17,871 16,941 Fuel 5,259 28,510 Other 28,793 34,706 Other current liabilities $ 247,013 $ 373,521

Leases

Leases	6 Months Ended
	Jun. 30, 2020
Leases [Abstract]
Leases	Leases The Company leases aircraft, engines, airport terminals, maintenance and training facilities, aircraft hangars, commercial real estate, and office and computer equipment, among other items. Certain of these leases include provisions for variable lease payments which are based on several factors, including, but not limited to, relative leased square footage, enplaned passengers, and airports’ annual operating budgets. Due to the variable nature of the rates, these leases are not recorded on the Company's condensed balance sheets as a right-of-use asset and lease liability. Lease terms are generally 8 years to 18 years for aircraft and up to 99 years for other leased equipment and property. As of June 30, 2020, the Company had a fleet consisting of 154 A320 family aircraft. As of June 30, 2020, the Company had 55 aircraft financed under operating leases with lease term expirations between 2022 and 2038. In addition, the Company owned 99 aircraft of which 29 were purchased off lease and were unencumbered as of June 30, 2020. As of June 30, 2020, the Company also had 8 spare engines financed under operating leases with lease term expiration dates ranging from 2023 to 2027 and owned 16 spare engines, all of which, as of June 30, 2020, were pledged as partial collateral under the Company's 2022 revolving credit facility. In accordance with Topic 842, the Company has elected not to apply the recognition requirements to short-term leases (i.e., leases of 12 months or less). Instead, lease payments are recognized in profit or loss on a straight-line basis over the lease term. In addition, variable lease payments in the period in which the obligation for those payments is incurred are not included in the recognition of a lease liability or right-of-use asset. Right-of-use assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent the Company's obligation to make lease payments arising from the lease. Right-of-use assets and liabilities are recognized at the lease commencement date based on the estimated present value of lease payments over the lease term. When available, the Company uses the rate implicit in the lease to discount lease payments to present value. However, the Company's leases generally do not provide a readily determinable implicit rate. Therefore, the Company estimates the incremental borrowing rate to discount lease payments based on information available at lease commencement. The Company uses publicly available data for instruments with similar characteristics when calculating its incremental borrowing rates. The Company has options to extend certain of its operating leases for an additional period of time and options to early terminate several of its operating leases. The lease term consists of the noncancellable period of the lease, periods covered by options to extend the lease if the Company is reasonably certain to exercise the option, periods covered by an option to terminate the lease if the Company is reasonably certain not to exercise the option and periods covered by an option to extend or not terminate the lease in which the exercise of the option is controlled by the lessor. The Company's lease agreements do not contain any residual value guarantees. The Company has elected to not separate non-lease components from the associated lease component for all underlying classes of assets with lease and non-lease components. Some of the Company’s aircraft and engine master lease agreements provide that the Company pays maintenance reserves to aircraft lessors to be held as collateral in advance of the Company’s required performance of major maintenance activities. A majority of these maintenance reserve payments are calculated based on a utilization measure, such as flight hours or cycles, while some maintenance reserve payments are fixed, time-based contractual amounts. Maintenance reserve payments that are probable of being recovered when the Company performs qualifying maintenance are recorded in aircraft maintenance deposits on the Company's condensed balance sheets. Fixed maintenance reserve payments that are not probable of being recovered are considered lease payments and are included in the right-of-use asset and lease liability. Maintenance reserve payments that are based on a utilization measure and are not probable of being recovered are considered variable lease payments that are recognized when they are probable of being incurred and are not included in the right-of-use asset and lease liability. Some of the master lease agreements do not require that the Company pay maintenance reserves so long as the Company's cash balance does not fall below a certain level. As of June 30, 2020, the Company is in full compliance with those requirements and does not anticipate having to pay reserves related to these master leases in the future. Aircraft rent expense consists of monthly lease rents for aircraft and spare engines under the terms of the Company's aircraft and spare engine lease agreements recognized on a straight-line basis. Aircraft rent expense also includes maintenance reserves paid to aircraft lessors in advance of the performance of major maintenance activities that are not probable of being reimbursed and probable lease return condition obligations. Under the terms of the lease agreements, the Company will continue to operate and maintain the aircraft. Payments under the majority of the lease agreements are fixed for the term of the lease. The lease agreements contain standard termination events, including termination upon a breach of the Company's obligations to make rental payments and upon any other material breach of the Company's obligations under the leases, and standard maintenance and return condition provisions. These return provisions are evaluated at inception of the lease and throughout the lease terms and are accounted for as either fixed or variable lease payments (depending on the nature of the lease return condition) when it is probable that such amounts will be incurred. When determining probability and estimated cost of lease return obligations, there are various other factors that need to be considered such as the contractual terms of the lease, the ability to swap engines or other aircraft components, current condition of the aircraft, the age of the aircraft at lease expiration, utilization of engines and other components, the extent of repairs needed at return, return locations, current configuration of the aircraft and cost of repairs and materials at the time of return. Management assesses the factors listed above and the need to accrue lease return costs throughout the lease as facts and circumstances warrant an assessment. As a result of COVID-19, the Company is currently operating its aircraft at lower utilization levels. If the Company continues flying its aircraft at lower utilization levels beyond its current projections, the timing of future maintenance events may change such that the Company will be required to accrue lease return costs and/or record reserves against its maintenance deposits earlier than it would have expected and such amounts could be significant. The Company expects lease return costs and unrecoverable maintenance deposits will increase as individual aircraft lease agreements approach their respective termination dates and the Company begins to accrue the estimated cost of return conditions for the corresponding aircraft. Upon a termination of the lease due to a breach by the Company, the Company would be liable for standard contractual damages, possibly including damages suffered by the lessor in connection with remarketing the aircraft or while the aircraft is not leased to another party. During the six months ended June 30, 2020, the Company took delivery of six aircraft under secured debt arrangements, purchased two previously leased aircraft, and took delivery of three aircraft under operating leases. In addition, the Company also purchased two engines and returned one previously leased engine. On December 31, 2019, the Company entered into an aircraft sale agreement to acquire two A319 aircraft previously operated by the Company under operating leases. The contract was deemed a lease modification, which resulted in a change of classification from operating leases to finance leases for the two aircraft. In January 2020, the purchase of the two aircraft was completed. These aircraft were recorded within flight equipment on the Company's condensed balance sheets as of June 30, 2020. As of June 30, 2020, the Company's finance lease obligations primarily relate to the lease of computer equipment used by the Company's flight crew and office equipment. Payments under these finance lease agreements are fixed for terms ranging from 4 to 5 years. Finance lease assets are recorded within property and equipment and the related liabilities are recorded within current maturities of long-term debt and finance leases and long-term debt and finance leases, less current maturities in the Company's condensed balance sheets. During the fourth quarter of 2019, the Company purchased an 8.5-acre parcel of land for $41.0 million and entered into a 99-year lease agreement for the lease of a 2.6-acre parcel of land, in Dania Beach, Florida, where the Company intends to build a new headquarters campus. In connection with the lease agreement, the Company is expected to build a 200-unit residential building. The 8.5-acre parcel of land is capitalized within ground property and equipment on the Company's condensed balance sheets. The 99-year lease was determined to be an operating lease and is recorded within operating lease right-of-use asset and operating lease liability on the Company's condensed balance sheets. Operating lease commitments related to this lease are included in the table below within property facility leases. The following table provides details of the Company's future minimum lease payments under finance lease liabilities and operating lease liabilities recorded on the Company's condensed balance sheets as of June 30, 2020. The table does not include commitments that are contingent on events or other factors that are currently uncertain or unknown. Finance Leases Operating Leases Aircraft and Spare Engine Leases Property Facility Leases Other Total (in thousands) remainder of 2020 $ 381 $ 102,077 $ 2,237 $ 228 $ 104,923 2021 753 204,153 4,552 — 209,458 2022 725 205,231 4,262 — 210,218 2023 349 192,586 3,260 — 196,195 2024 98 170,524 2,722 — 173,344 2025 and thereafter — 1,065,928 144,127 — 1,210,055 Total minimum lease payments $ 2,306 $ 1,940,499 $ 161,160 $ 228 $ 2,104,193 Less amount representing interest 192 568,343 135,335 3 703,873 Present value of minimum lease payments $ 2,114 $ 1,372,156 $ 25,825 $ 225 $ 1,400,320 Less current portion 658 125,219 3,092 225 129,194 Long-term portion $ 1,456 $ 1,246,937 $ 22,733 $ — $ 1,271,126 Commitments related to the Company's noncancellable short-term operating leases not recorded on the Company's condensed balance sheets are expected to be $2.6 million for the remainder of 2020 and none for 2021 and beyond . During the six months ended 2020, the Company e ntered into agreements to defer payments in 2020 related to facility rents and other airport services contracts at certain locations. The table below presents information for lease costs related to the Company's finance and operating leases: Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands) Finance lease cost Amortization of leased assets $ 135 $ 519 $ 270 $ 728 Interest of lease liabilities 26 309 139 339 Operating lease cost Operating lease cost (1) 51,006 48,639 98,223 98,353 Short-term lease cost (1) 6,884 3,509 13,598 6,958 Variable lease cost (1) 25,568 31,653 55,383 59,770 Total lease cost $ 83,619 $ 84,629 $ 167,613 $ 166,148 (1) Expenses are classified within aircraft rent and landing fees and other rents on the Company's condensed statements of operations. The table below presents lease terms and discount rates related to the Company's finance and operating leases: June 30, 2020 June 30, 2019 Weighted-average remaining lease term Operating leases 13.1 years 9.8 years Finance leases 3.1 years 0.8 years Weighted-average discount rate Operating leases 6.07 % 6.52 % Finance leases 5.56 % 3.93 %
Leases	Leases The Company leases aircraft, engines, airport terminals, maintenance and training facilities, aircraft hangars, commercial real estate, and office and computer equipment, among other items. Certain of these leases include provisions for variable lease payments which are based on several factors, including, but not limited to, relative leased square footage, enplaned passengers, and airports’ annual operating budgets. Due to the variable nature of the rates, these leases are not recorded on the Company's condensed balance sheets as a right-of-use asset and lease liability. Lease terms are generally 8 years to 18 years for aircraft and up to 99 years for other leased equipment and property. As of June 30, 2020, the Company had a fleet consisting of 154 A320 family aircraft. As of June 30, 2020, the Company had 55 aircraft financed under operating leases with lease term expirations between 2022 and 2038. In addition, the Company owned 99 aircraft of which 29 were purchased off lease and were unencumbered as of June 30, 2020. As of June 30, 2020, the Company also had 8 spare engines financed under operating leases with lease term expiration dates ranging from 2023 to 2027 and owned 16 spare engines, all of which, as of June 30, 2020, were pledged as partial collateral under the Company's 2022 revolving credit facility. In accordance with Topic 842, the Company has elected not to apply the recognition requirements to short-term leases (i.e., leases of 12 months or less). Instead, lease payments are recognized in profit or loss on a straight-line basis over the lease term. In addition, variable lease payments in the period in which the obligation for those payments is incurred are not included in the recognition of a lease liability or right-of-use asset. Right-of-use assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent the Company's obligation to make lease payments arising from the lease. Right-of-use assets and liabilities are recognized at the lease commencement date based on the estimated present value of lease payments over the lease term. When available, the Company uses the rate implicit in the lease to discount lease payments to present value. However, the Company's leases generally do not provide a readily determinable implicit rate. Therefore, the Company estimates the incremental borrowing rate to discount lease payments based on information available at lease commencement. The Company uses publicly available data for instruments with similar characteristics when calculating its incremental borrowing rates. The Company has options to extend certain of its operating leases for an additional period of time and options to early terminate several of its operating leases. The lease term consists of the noncancellable period of the lease, periods covered by options to extend the lease if the Company is reasonably certain to exercise the option, periods covered by an option to terminate the lease if the Company is reasonably certain not to exercise the option and periods covered by an option to extend or not terminate the lease in which the exercise of the option is controlled by the lessor. The Company's lease agreements do not contain any residual value guarantees. The Company has elected to not separate non-lease components from the associated lease component for all underlying classes of assets with lease and non-lease components. Some of the Company’s aircraft and engine master lease agreements provide that the Company pays maintenance reserves to aircraft lessors to be held as collateral in advance of the Company’s required performance of major maintenance activities. A majority of these maintenance reserve payments are calculated based on a utilization measure, such as flight hours or cycles, while some maintenance reserve payments are fixed, time-based contractual amounts. Maintenance reserve payments that are probable of being recovered when the Company performs qualifying maintenance are recorded in aircraft maintenance deposits on the Company's condensed balance sheets. Fixed maintenance reserve payments that are not probable of being recovered are considered lease payments and are included in the right-of-use asset and lease liability. Maintenance reserve payments that are based on a utilization measure and are not probable of being recovered are considered variable lease payments that are recognized when they are probable of being incurred and are not included in the right-of-use asset and lease liability. Some of the master lease agreements do not require that the Company pay maintenance reserves so long as the Company's cash balance does not fall below a certain level. As of June 30, 2020, the Company is in full compliance with those requirements and does not anticipate having to pay reserves related to these master leases in the future. Aircraft rent expense consists of monthly lease rents for aircraft and spare engines under the terms of the Company's aircraft and spare engine lease agreements recognized on a straight-line basis. Aircraft rent expense also includes maintenance reserves paid to aircraft lessors in advance of the performance of major maintenance activities that are not probable of being reimbursed and probable lease return condition obligations. Under the terms of the lease agreements, the Company will continue to operate and maintain the aircraft. Payments under the majority of the lease agreements are fixed for the term of the lease. The lease agreements contain standard termination events, including termination upon a breach of the Company's obligations to make rental payments and upon any other material breach of the Company's obligations under the leases, and standard maintenance and return condition provisions. These return provisions are evaluated at inception of the lease and throughout the lease terms and are accounted for as either fixed or variable lease payments (depending on the nature of the lease return condition) when it is probable that such amounts will be incurred. When determining probability and estimated cost of lease return obligations, there are various other factors that need to be considered such as the contractual terms of the lease, the ability to swap engines or other aircraft components, current condition of the aircraft, the age of the aircraft at lease expiration, utilization of engines and other components, the extent of repairs needed at return, return locations, current configuration of the aircraft and cost of repairs and materials at the time of return. Management assesses the factors listed above and the need to accrue lease return costs throughout the lease as facts and circumstances warrant an assessment. As a result of COVID-19, the Company is currently operating its aircraft at lower utilization levels. If the Company continues flying its aircraft at lower utilization levels beyond its current projections, the timing of future maintenance events may change such that the Company will be required to accrue lease return costs and/or record reserves against its maintenance deposits earlier than it would have expected and such amounts could be significant. The Company expects lease return costs and unrecoverable maintenance deposits will increase as individual aircraft lease agreements approach their respective termination dates and the Company begins to accrue the estimated cost of return conditions for the corresponding aircraft. Upon a termination of the lease due to a breach by the Company, the Company would be liable for standard contractual damages, possibly including damages suffered by the lessor in connection with remarketing the aircraft or while the aircraft is not leased to another party. During the six months ended June 30, 2020, the Company took delivery of six aircraft under secured debt arrangements, purchased two previously leased aircraft, and took delivery of three aircraft under operating leases. In addition, the Company also purchased two engines and returned one previously leased engine. On December 31, 2019, the Company entered into an aircraft sale agreement to acquire two A319 aircraft previously operated by the Company under operating leases. The contract was deemed a lease modification, which resulted in a change of classification from operating leases to finance leases for the two aircraft. In January 2020, the purchase of the two aircraft was completed. These aircraft were recorded within flight equipment on the Company's condensed balance sheets as of June 30, 2020. As of June 30, 2020, the Company's finance lease obligations primarily relate to the lease of computer equipment used by the Company's flight crew and office equipment. Payments under these finance lease agreements are fixed for terms ranging from 4 to 5 years. Finance lease assets are recorded within property and equipment and the related liabilities are recorded within current maturities of long-term debt and finance leases and long-term debt and finance leases, less current maturities in the Company's condensed balance sheets. During the fourth quarter of 2019, the Company purchased an 8.5-acre parcel of land for $41.0 million and entered into a 99-year lease agreement for the lease of a 2.6-acre parcel of land, in Dania Beach, Florida, where the Company intends to build a new headquarters campus. In connection with the lease agreement, the Company is expected to build a 200-unit residential building. The 8.5-acre parcel of land is capitalized within ground property and equipment on the Company's condensed balance sheets. The 99-year lease was determined to be an operating lease and is recorded within operating lease right-of-use asset and operating lease liability on the Company's condensed balance sheets. Operating lease commitments related to this lease are included in the table below within property facility leases. The following table provides details of the Company's future minimum lease payments under finance lease liabilities and operating lease liabilities recorded on the Company's condensed balance sheets as of June 30, 2020. The table does not include commitments that are contingent on events or other factors that are currently uncertain or unknown. Finance Leases Operating Leases Aircraft and Spare Engine Leases Property Facility Leases Other Total (in thousands) remainder of 2020 $ 381 $ 102,077 $ 2,237 $ 228 $ 104,923 2021 753 204,153 4,552 — 209,458 2022 725 205,231 4,262 — 210,218 2023 349 192,586 3,260 — 196,195 2024 98 170,524 2,722 — 173,344 2025 and thereafter — 1,065,928 144,127 — 1,210,055 Total minimum lease payments $ 2,306 $ 1,940,499 $ 161,160 $ 228 $ 2,104,193 Less amount representing interest 192 568,343 135,335 3 703,873 Present value of minimum lease payments $ 2,114 $ 1,372,156 $ 25,825 $ 225 $ 1,400,320 Less current portion 658 125,219 3,092 225 129,194 Long-term portion $ 1,456 $ 1,246,937 $ 22,733 $ — $ 1,271,126 Commitments related to the Company's noncancellable short-term operating leases not recorded on the Company's condensed balance sheets are expected to be $2.6 million for the remainder of 2020 and none for 2021 and beyond . During the six months ended 2020, the Company e ntered into agreements to defer payments in 2020 related to facility rents and other airport services contracts at certain locations. The table below presents information for lease costs related to the Company's finance and operating leases: Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands) Finance lease cost Amortization of leased assets $ 135 $ 519 $ 270 $ 728 Interest of lease liabilities 26 309 139 339 Operating lease cost Operating lease cost (1) 51,006 48,639 98,223 98,353 Short-term lease cost (1) 6,884 3,509 13,598 6,958 Variable lease cost (1) 25,568 31,653 55,383 59,770 Total lease cost $ 83,619 $ 84,629 $ 167,613 $ 166,148 (1) Expenses are classified within aircraft rent and landing fees and other rents on the Company's condensed statements of operations. The table below presents lease terms and discount rates related to the Company's finance and operating leases: June 30, 2020 June 30, 2019 Weighted-average remaining lease term Operating leases 13.1 years 9.8 years Finance leases 3.1 years 0.8 years Weighted-average discount rate Operating leases 6.07 % 6.52 % Finance leases 5.56 % 3.93 %

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Aircraft-Related Commitments and Financing Arrangements The Company’s contractual purchase commitments consist primarily of aircraft and engine acquisitions through manufacturers and aircraft leasing companies. During the fourth quarter of 2019, the Company entered into an A320 NEO Family Purchase Agreement with Airbus for the purchase of 100 new Airbus A320neo family aircraft, with options to purchase up to 50 additional aircraft. In June 2020, the Company entered into an agreement to defer certain aircraft deliveries scheduled in 2020 and 2021, as well as the related pre-delivery deposit payments. During the six months ended June 30, 2020, the Company took delivery of 9 aircraft and with this agreement, the Company has 3 remaining aircraft scheduled for delivery during the remainder of 2020 and 16 aircraft scheduled for delivery in 2021. For additional information, please refer to Note 2, Impact of COVID-19. As of June 30, 2020, the Company's total firm aircraft orders consisted of 129 A320 family aircraft with Airbus, including A319neos, A320neos and A321neos, with deliveries expected through 2027. In addition, the Company has financing agreements in place for 10 direct operating leases for A320neos with third-party lessors with deliveries scheduled in 2021. The Company also has one spare engine order for a V2500 SelectTwo engine with International Aero Engines ("IAE") and two spare engine orders for PurePower PW1100G-JM engines with Pratt & Whitney. Spare engines are scheduled for delivery from 2021 through 2023. As of June 30, 2020, purchase commitments for these aircraft and engines, including estimated amounts for contractual price escalations and pre-delivery payments, are expected to be $119.0 million for the remainder of 2020, $356.4 million in 2021, $606.1 million in 2022, $707.6 million in 2023, $1,073.0 million in 2024, and $3,763.4 million in 2025 and beyond. During the third quarter of 2019, the United States announced its decision to levy tariffs on certain imports from the European Union, including commercial aircraft and related parts. These tariffs include aircraft and other parts that the Company is already contractually obligated to purchase including those reflected above. In February 2020, the rate of this tariff was increased from 10% to 15%. The imposition of these tariffs may substantially increase the cost of new Airbus aircraft and parts required to service the Company's Airbus fleet. As of June 30, 2020, the Company has secured debt financing commitments for two aircraft scheduled for delivery from Airbus in 2020. As of June 30, 2020, the Company did not have financing commitments in place for the remaining 127 Airbus aircraft on firm order through 2027. However, the Company has a financing letter of agreement with Airbus which provides backstop financing for a majority of the aircraft included in the A320 NEO Family Purchase Agreement signed in the fourth quarter of 2019. The agreement provides a standby credit facility in the form of senior secured mortgage debt financing. In addition, as of June 30, 2020, the Company has secured 10 direct operating leases for A320neos with third-party lessors, with deliveries expected in 2021. As of June 30, 2020, principal and interest commitments related to the Company's future secured debt financing of the two undelivered aircraft are approximately $0.9 million for the remainder of 2020, $8.5 million in 2021, $6.5 million in 2022, $7.0 million in 2023, $7.1 million in 2024, and $64.7 million in 2025 and beyond. Aircraft rent commitments for future aircraft deliveries to be financed under direct leases from third-party lessors are expected to be approximately zero for the remainder of 2020, $18.2 million in 2021, $33.4 million in 2022, $33.4 million in 2023, $33.4 million in 2024, and $282.5 million in 2025 and beyond. Interest commitments related to the secured debt financing of 70 delivered aircraft as of June 30, 2020 are $40.7 million for the remainder of 2020, $76.2 million in 2021, $69.5 million in 2022, $58.9 million in 2023, $47.9 million in 2024, and $131.2 million in 2025 and beyond. As of June 30, 2020, interest commitments related to the Company's unsecured term loans and convertible debt financing are $4.4 million for the remainder of 2020, $8.9 million in 2021, $8.9 million in 2022, $8.9 million in 2023, $8.9 million in 2024, and $10.7 million in 2025 and beyond. For principal commitments related to the Company's debt financing, refer to Note 13, Debt and Other Obligations. The Company is contractually obligated to pay the following minimum guaranteed payments for its reservation system and other miscellaneous subscriptions and services as of June 30, 2020: $10.7 million for the remainder of 2020, $17.1 million in 2021, $16.2 million in 2022, $14.4 million in 2023, $14.5 million in 2024, and $50.3 million in 2025 and thereafter. During the first quarter of 2018, the Company entered into a contract renewal with its reservation system provider which expires in 2028. Litigation The Company is subject to commercial litigation claims and to administrative and regulatory proceedings and reviews that may be asserted or maintained from time to time. The Company believes the ultimate outcome of such lawsuits, proceedings and reviews will not, individually or in the aggregate, have a material adverse effect on its financial position, liquidity or results of operations. Credit Card Processing Arrangements The Company has agreements with organizations that process credit card transactions arising from the purchase of air travel, baggage charges, and other ancillary services by customers. As is standard in the airline industry, the Company's contractual arrangements with credit card processors permit them, under certain circumstances, to retain a holdback or other collateral, which the Company records as restricted cash, when future air travel and other future services are purchased via credit card transactions. The required holdback is the percentage of the Company's overall credit card sales that its credit card processors hold to cover refunds to customers if the Company fails to fulfill its flight obligations. The Company's credit card processors do not require the Company to maintain cash collateral provided that the Company satisfies certain liquidity and other financial covenants. Failure to meet these covenants would provide the processors the right to place a holdback resulting in a commensurate reduction of unrestricted cash. As of June 30, 2020 and December 31, 2019, the Company's credit card processors were holding back no remittances. The maximum potential exposure to cash holdbacks by the Company's credit card processors, based upon advance ticket sales and $9 Fare Club memberships as of June 30, 2020 and December 31, 2019, was $417.3 million and $342.3 million, respectively. Employees The Company has 5 union-represented employee groups that together represented approximately 81% of all employees as of June 30, 2020. The table below sets forth the Company's employee groups and status of the collective bargaining agreements as of June 30, 2020. Employee Groups Representative Amendable Date Percentage of Workforce Pilots Air Line Pilots Association, International ("ALPA") February 2023 28% Flight Attendants Association of Flight Attendants ("AFA-CWA") May 2021 46% Dispatchers Professional Airline Flight Control Association ("PAFCA") October 2023 1% Ramp Service Agents International Association of Machinists and Aerospace Workers ("IAMAW") June 2020 3% Passenger Service Agents Transport Workers Union of America ("TWU") NA 3% In February 2020, the IAMAW notified the Company, as required by the Railway Labor Act, that it intends to submit proposed changes to the collective bargaining agreement covering the Company's ramp service agents which became amendable in June 2020. The parties expect to schedule meeting dates for negotiations soon. The Company's passenger service agents are represented by the TWU, but the representation applies only to the Company's Fort Lauderdale station where the Company has direct employees in the passenger service classification. The Company and the TWU began meeting in late October 2018 to negotiate an initial collective bargaining agreement. As of June 30, 2020, the Company continued to negotiate with the TWU. The Company is self-insured for healthcare claims, up to a stop-loss amount for eligible participating employees and qualified dependent medical claims, subject to deductibles and limitations. The Company’s liabilities for claims incurred but not reported are determined based on an estimate of the ultimate aggregate liability for claims incurred. The estimate is calculated from actual claim rates and adjusted periodically as necessary. The Company has accrued $5.2 million and $5.2 million in health care claims as of June 30, 2020 and December 31, 2019, respectively.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Under ASC 820, "Fair Value Measurements and Disclosures," disclosures relating to how fair value is determined for assets and liabilities are required, and a hierarchy for which these assets and liabilities must be grouped is established, based on significant levels of inputs, as follows: Level 1 —Quoted prices in active markets for identical assets or liabilities. Level 2 —Observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 —Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The Company utilizes several valuation techniques in order to assess the fair value of the Company’s financial assets and liabilities. The Company records impairment charges on long-lived assets used in operations when events and circumstances indicate that the assets may be impaired, the undiscounted cash flows estimated to be generated by those assets are less than the carrying amount of those assets, and the net book value of the assets exceeds their estimated fair value. The Company has assessed whether any impairment of its long-lived assets existed and has determined that no charges were deemed necessary under applicable accounting standards as of June 30, 2020. The Company’s assumptions about future conditions important to its assessment of potential impairment of its long-lived assets, including the impact of the COVID-19 pandemic to its business, are subject to uncertainty, and the Company will continue to monitor these conditions in future periods as new information becomes available, and will update its analyses accordingly. Long-Term Debt The estimated fair value of the Company's term loan debt agreements and revolving credit facilities have been determined to be Level 3 as certain inputs used to determine the fair value of these agreements are unobservable. The Company utilizes a discounted cash flow method to estimate the fair value of the Level 3 long-term debt. The estimated fair value of the Company's publicly and non-publicly held EETC debt agreements and the Company's convertible notes has been determined to be Level 2 as the Company utilizes quoted market prices in markets with low trading volumes to estimate the fair value of its Level 2 long-term debt. The carrying amounts and estimated fair values of the Company's long-term debt at June 30, 2020 and December 31, 2019 were as follows: June 30, 2020 December 31, 2019 Fair Value Level Hierarchy Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value (in millions) Fixed-rate senior term loans $ 279.4 $ 262.8 $ 296.1 $ 296.4 Level 3 Fixed-rate term loans 992.2 976.8 778.2 823.6 Level 3 Unsecured term loans 60.4 60.4 — — Level 3 2015-1 EETC Class A 333.5 321.9 348.6 372.2 Level 2 2015-1 EETC Class B 68.0 59.3 72.0 74.5 Level 2 2015-1 EETC Class C 92.4 65.8 98.1 100.5 Level 2 2017-1 EETC Class AA 221.4 208.1 228.4 237.0 Level 2 2017-1 EETC Class A 73.8 61.8 76.1 78.8 Level 2 2017-1 EETC Class B 65.6 51.8 70.6 72.0 Level 2 2017-1 EETC Class C 85.5 60.5 85.5 88.0 Level 2 Convertible debt 101.4 264.1 — — Level 2 Revolving credit facilities 291.2 291.2 160.0 160.0 Level 3 Total long-term debt $ 2,664.8 $ 2,684.5 $ 2,213.6 $ 2,303.0 Cash and Cash Equivalents Cash and cash equivalents at June 30, 2020 and December 31, 2019 are comprised of liquid money market funds and cash, and are categorized as Level 1 instruments. The Company maintains cash with various high-quality financial institutions. Restricted Cash Restricted cash is comprised of cash held in account subject to account control agreements or otherwise pledged as collateral against the Company's letters of credit and is categorized as a Level 1 instrument. As of June 30, 2020, the Company had a $30.0 million standby letter of credit secured by cash, of which $23.1 million had been drawn upon for issued letters of credit. Short-term Investment Securities Short-term investment securities at June 30, 2020 and December 31, 2019 are classified as available-for-sale and generally consist of U.S. Treasury and U.S. government agency securities with contractual maturities of 12 months or less. The Company's short-term investment securities are categorized as Level 1 instruments, as the Company uses quoted market prices in active markets when determining the fair value of these securities. For additional information, refer to Note 8, Short-term Investment Securities. Assets Held for Sale The Company's assets held for sale consist of rotable aircraft parts. When long-lived assets are identified as held for sale and the required criteria are met, the Company reclassifies the assets from property and equipment to prepaid expenses and other current assets on the Company's condensed balance sheets and discontinues depreciation. The assets are measured at the lower of the carrying amount or fair value less cost to sell and a loss is recognized for any initial adjustment of the asset’s carrying amount to fair value less cost to sell. Such valuations include estimations of fair values and incremental direct costs to transact a sale. The fair value measurements for the Company's held-for-sale assets were based on Level 3 inputs, which include information obtained from third-party valuation sources. As of June 30, 2020 and December 31, 2019, the Company had $2.3 million in assets held for sale recorded within prepaid expenses and other current assets in the Company's condensed balance sheets. Assets and liabilities measured at gross fair value on a recurring basis are summarized below: Fair Value Measurements as of June 30, ,2020 Total Level Level Level (in millions) Cash and cash equivalents $ 1,127.5 $ 1,127.5 $ — $ — Restricted cash 30.0 30.0 — — Short-term investment securities 106.3 106.3 — — Assets held for sale 2.3 — — 2.3 Total assets $ 1,266.1 $ 1,263.8 $ — $ 2.3 Total liabilities $ — $ — $ — $ — Fair Value Measurements as of December 31, 2019 Total Level Level Level (in millions) Cash and cash equivalents $ 979.0 $ 979.0 $ — $ — Short-term investment securities 105.3 105.3 — — Assets held for sale 2.3 2.3 Total assets $ 1,086.6 $ 1,084.3 $ — $ 2.3 Total liabilities $ — $ — $ — $ — The Company had no transfers of assets or liabilities between any of the above levels during the three months ended June 30, 2020 and the year ended December 31, 2019. Assets Held for Sale Activity for the Six Months Ended June 30, 2020 (in millions) Balance at December 31, 2019 $ 2.3 Purchases — Sales — Total realized or unrealized gains (losses) included in earnings, net $ — Balance at March 31, 2020 $ 2.3 Purchases — Sales — Total realized or unrealized gains (losses) included in earnings, net — Balance at June 30, 2020 $ 2.3

Debt and Other Obligations

Debt and Other Obligations	6 Months Ended
	Jun. 30, 2020
Debt Disclosure [Abstract]
Debt and Other Obligations	Debt and Other Obligations As of June 30, 2020, the Company had outstanding non-public and public debt instruments. During the six months ended June 30, 2020, the Company incurred debt through fixed-rate secured and unsecured term loans, secured a new revolving credit facility and issued convertible notes described below. Fixed-rate secured term loans The Company entered into facility agreements which as of June 30, 2020, provided $249.0 million for six Airbus A320 aircraft delivered during the six months ended June 30, 2020. The loans extended under these facility agreements are secured by a first-priority security interest on the individual aircraft. These loans have a term life of 11 to 12 years and amortize on a mortgage-style basis, which requires quarterly principal and interest payments. Fixed-rate unsecured term loans On April 20, 2020, the Company entered into the PSP agreement with the Treasury, pursuant to which the Company has received $301.3 million as of June 30, 2020 and expects to receive an additional $33.4 million on or about July 31, 2020 for a total of $334.7 million under the PSP. These funds are to be used exclusively to pay for salaries, wages and benefits for the Company’s Team Members through September 30, 2020. Of the total amount received as of June 30, 2020, $60.4 million is in the form of a low-interest 10-year unsecured term loan. Of the $33.4 million expected in July 2020, $10.0 million will be in the form of an unsecured term loan under the PSP agreement, resulting in an expected maximum principal amount of $70.4 million. Interest on the loan is payable semi-annually at a rate of 1.0% in years 1 through 5 and a rate of the Secured Overnight Financing Rate plus 2.0% in years 6 through 10. The notes are prepayable at any time, without penalty, at the Company’s option and have principal due at maturity in 2030. The Company has concluded that no terms exist within the contract that would require a short-term classification of the debt instrument within the Company’s condensed balance sheet at the inception of the loan. Therefore, the debt has been recorded at face value and classified within long-term debt in the Company’s condensed balance sheets. As of June 30, 2020, the Company had recorded $60.4 million in long-term debt on its condensed balance sheets, related to the PSP. Revolving credit facility due in 2022 On March 30, 2020, the Company entered into the 2022 revolving credit facility for $110.0 million, with an option to increase the overall commitment amount up to $350 million with the consent of any participating lenders and subject to borrowing base availability. In the second quarter of 2020, the commitment was increased to $180.0 million. As of June 30, 2020, the Company had fully drawn the $180.0 million available. Any amounts drawn on this facility are included in long-term debt and finance leases, less current maturities on the Company's condensed balance sheets. The final maturity of the facility is March 30, 2022. The Company may pledge the following types of assets as collateral to secure its obligations under the revolving credit facility: (i) certain take-off and landing rights of the Company at LaGuardia Airport, (ii) certain eligible aircraft spare parts and ground support equipment, (iii) aircraft, spare engines and flight simulators, (v) real property assets and (vi) cash and cash equivalents. The revolving credit facility bears variable interest based on LIBOR, plus a 2.00% margin per annum, or another rate, at the Company's election, based on certain market interest rates, plus a 1.00% margin per annum, in each case with a floor of 0%. The 2022 revolving credit facility requires the Company to maintain (i) so long as any loans or letters of credit are outstanding under the 2022 revolving credit facility, unrestricted cash and cash equivalents and unused commitments available under all revolving credit facilities (including the 2022 revolving credit facility) aggregating not less than $400 million, of which no more than $200 million may be derived from unused commitments under the 2022 revolving credit facility, (ii) a minimum ratio of the borrowing base of the collateral described above (determined as the sum of a specified percentage of the appraised value of each type of such collateral) to outstanding obligations under the 2022 revolving credit facility of not less than 1.0 to 1.0 (if the Company does not meet the minimum collateral coverage ratio, it must either provide additional collateral to secure its obligations under the 2022 revolving credit facility or repay the loans under the 2022 revolving credit facility by an amount necessary to maintain compliance with the collateral coverage ratio), and (iii) at any time following the date that is one month after the effective date of the 2022 revolving credit facility, the pledged take-off and landing rights of the Company at LaGuardia Airport and a specified number of spare engines in the collateral described above so long as any loans or letters of credit are outstanding under the 2022 revolving credit facility. Revolving credit facility due in 2021 During the fourth quarter of 2018, the Company entered into a revolving credit facility for up to $160.0 million secured by the collateral assignment of certain of the Company's rights under the purchase agreement with Airbus, related to 43 Airbus A320neo aircraft scheduled to be delivered between August 2019 and December 2021. In June 2020, the Company entered into an agreement to amend the revolving credit facility originally maturing in December 2020. The agreement amends the revolving credit facility to extend the final maturity date from December 30, 2020 to March 31, 2021. Upon execution of the amended agreement, the maximum borrowing capacity decreased from $160.0 million to $111.2 million. This facility is secured by the collateral assignment of certain of the Company’s rights under the purchase agreement with Airbus, related to 20 Airbus A320neo aircraft scheduled to be delivered between August 2020 and September 2022. The initial maximum borrowing capacity of $111.2 million will decrease as the Company takes delivery of the related aircraft. As of June 30, 2020 and December 31, 2019, the Company had drawn $111.2 million and $160.0 million , respectively, on the facility, which is included in current maturities of long-term debt and capital leases on the Company's condensed balance sheets. The revolving credit facility bears variable interest based on LIBOR. Convertible debt On May 12, 2020, the Company completed the public offering of $175.0 million aggregate principal amount of 4.75% convertible senior notes due 2025. The convertible notes bear interest at the rate of 4.75% per year and will mature on May 15, 2025. Interest on the notes is payable semi-annually in arrears on May 15 and November 15 of each year, beginning on November 15, 2020. To allocate the proceeds of the convertible notes, the Company first determined the fair value of the debt component of the convertible notes based on a similar liability with no conversion feature and utilized a discounted cash flow method whereby the contractual cash flows have been discounted at a risk-adjusted yield reflective of both the time value of money and the credit risk inherent in the convertible notes, as well as certain observable inputs. The Company allocated the remaining proceeds of the convertible notes to the equity component within APIC. The Company will accrete the resulting discount on the debt component through interest expense, using the effective interest method, over the 5-year life of the instrument. The Company received proceeds of $168.3 million as a result of the offering, net of total issuance costs of $6.7 million . The Company recorded $95.6 million in long-term debt, net of debt issuance costs of $3.8 million on its condensed balance sheets, related to the debt component of the convertible notes, and $72.7 million in APIC, net of issuance costs of $2.9 million on its condensed balance sheets, related to the equity component of the convertible notes. As of June 30, 2020, the if-converted value exceeds the principal amount of the convertible notes by $38 million using an average stock price in the period. Noteholders may convert their notes at their option only in the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on June 30, 2020 (and only during such calendar quarter), if the last reported sale price per share of the Company’s common stock exceeds 130% of the conversion price for each of at least 20 trading days (whether or not consecutive) during the 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter; (2) during the five five five consecutive trading day period, the “measurement period”) in which the trading price per $1,000 principal amount of notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price per share of the Company’s common stock on such trading day and the conversion rate on such trading day; (3) upon the occurrence of certain corporate events or distributions on the Company’s common stock; and (4) at any time from, and including, February 18, 2025 until the close of business on the second scheduled trading day immediately before the maturity date. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of the Company’s common stock or a combination of cash and shares of common stock, at the Company’s election. The initial conversion rate is 78.4314 shares of voting common stock per $1,000 principal amount of convertible notes (equivalent to an initial conversion price of approximately $12.75 per share of common stock). The conversion rate will be subject to adjustment in some events but will not be adjusted for any accrued and unpaid interest. In addition, following certain corporate events that occur prior to the maturity date, the Company will increase the conversion rate for a holder who elects to convert its convertible notes in connection with such a corporate event in certain circumstances. In the event of a “Fundamental Change,” as defined in the indenture governing the convertible notes, the holders may require the Company to purchase for cash all or a portion of their notes at a purchase price equal to the principal amount of the notes, plus accrued and unpaid interest, if any. The Company may not redeem the notes at its option prior to the maturity date. Long-term debt is comprised of the following: As of As of June 30, 2020 December 31, 2019 June 30, 2020 December 31, 2019 (in millions) (weighted-average interest rates) Fixed-rate senior term loans due through 2027 $ 279.4 $ 296.1 3.55 % 4.02 % Fixed-rate loans due through 2031 992.2 778.2 3.34 % 3.70 % Unsecured term loans due in 2030 60.4 — 1.00 % N/A Fixed-rate class A 2015-1 EETC due through 2028 333.5 348.6 4.10 % 4.10 % Fixed-rate class B 2015-1 EETC due through 2024 68.0 72.0 4.45 % 4.45 % Fixed-rate class C 2015-1 EETC due through 2023 92.4 98.1 4.93 % 4.93 % Fixed-rate class AA 2017-1 EETC due through 2030 221.4 228.4 3.38 % 3.38 % Fixed-rate class A 2017-1 EETC due through 2030 73.8 76.1 3.65 % 3.65 % Fixed-rate class B 2017-1 EETC due through 2026 65.6 70.6 3.80 % 3.80 % Fixed-rate class C 2017-1 EETC due through 2023 85.5 85.5 5.11 % 5.11 % Convertible debt due in 2025 101.4 — 4.75 % N/A Revolving credit facility due in 2021 111.2 160.0 1.58 % 3.12 % Revolving credit facility due in 2022 180.0 — 2.19 % N/A Long-term debt 2,664.8 2,213.6 Less current maturities 287.8 214.0 Less unamortized discounts, net 44.8 40.4 Total $ 2,332.2 $ 1,959.2 During the three and six months ended June 30, 2020 the Company made scheduled principal payments of $106.9 million and $149.4 million, respectively, on its outstanding debt obligations. During the three and six months ended and June 30, 2019, the Company made scheduled principal payments of $47.9 million and $85.8 million, respectively, on its outstanding debt obligations. At June 30, 2020, long-term debt principal payments for the next five years and thereafter are as follows: June 30, 2020 (in millions) remainder of 2020 $ 110.2 2021 278.3 2022 365.6 2023 329.8 2024 215.1 2025 and beyond 1,365.8 Total debt principal payments $ 2,664.8 Interest Expense Interest expense related to long-term debt and finance leases consists of the following: Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands) Fixed-rate senior term loans $ 2,601 $ 3,878 $ 5,414 $ 7,823 Fixed-rate junior term loans — 489 — 1,012 Fixed-rate term loans 8,210 6,432 15,823 12,634 Unsecured term loans 57 — 57 — Class A 2015-1 EETC 3,403 3,709 6,952 7,547 Class B 2015-1 EETC 752 841 1,548 1,721 Class C 2015-1 EETC 1,138 1,280 2,347 2,615 Class AA 2017-1 EETC 1,868 1,997 3,755 3,986 Class A 2017-1 EETC 673 720 1,354 1,437 Class B 2017-1 EETC 623 737 1,267 1,491 Class C 2017-1 EETC 1,092 1,092 2,184 2,171 Convertible debt (1) 3,138 — 3,138 — Revolving credit facilities 1,456 1,559 2,614 2,973 Amortization of deferred financing costs 2,526 2,177 4,632 4,369 Commitment and other fees 228 46 445 119 Finance leases 27 309 140 339 Total $ 27,792 $ 25,266 $ 51,670 $ 50,237 (1) Includes $2.0 million of accretion and $1.1 million of interest expense for the three and six months ended June 30, 2020.

Equity

Equity	6 Months Ended
	Jun. 30, 2020
Equity [Abstract]
Equity	Equity Common Stock Offering On May 12, 2020, Spirit Airlines, Inc. (the “Company”) completed the public offering of 20,125,000 shares of voting common stock of the Company, which includes full exercise of the underwriters’ option to purchase an additional 2,625,000 shares of common stock, at a public offering price of $10.00 per share (the “Common Stock Offering”). In connection with the common stock offering, the Company received proceeds of $192.4 million , net of $8.9 million in related issuance costs. The Company recorded common stock a t par of $20.2 thousand a nd the excess proceeds within APIC. Preferred Stock and Material Modifications to Rights of Security Holders On March 29, 2020, the Board of Directors of the Company declared a dividend of one preferred stock purchase right (a “Right”) for each outstanding share of common stock of the Company. The dividend was paid on April 9, 2020 (the “Record Date”) to holders of record as of the close of business on that date. Pursuant to a Rights Agreement (the "Rights Agreement") between the Company and Equiniti Trust Company, as Rights Agent. The Rights will initially trade with, and will be inseparable from, the Company's common stock, and the registered holders of the Company's common stock will be deemed to be the registered holders of the Rights. In addition, each share issued upon conversion of the convertible notes and the common stock issued on May 12, 2020 pursuant to our offering of common stock will have such Right. The Board of Directors has adopted the Rights Agreement to reduce the likelihood that a potential acquirer would gain (or seek to influence or change) control of the Company by open market accumulation or other tactics without paying an appropriate premium for the Company’s shares. In general terms and subject to certain exceptions, it works by imposing a significant penalty upon any person or group (including a group of persons that are acting in concert with each other) that acquires 10% or more of the outstanding common stock of the Company without the approval of the Board of Directors. The Rights will not be exercisable until after the Distribution Date (as defined below). After the Distribution Date, each Right will be exercisable to purchase, for $60.00 (the “Purchase Price”), one one-thousandth of a share of Series A Participating Cumulative Preferred Stock, par value $0.0001 per share (the “Preferred Stock”). This portion of a share of Preferred Stock will give the stockholder approximately the same dividend, voting or liquidation rights as would one share of the Company’s common stock. Prior to exercise, Rights holders in their capacity as such have no rights as a stockholder of the Company, including the right to vote and to receive dividends. The Rights will expire on March 29, 2021, unless earlier exercised, exchanged, amended or redeemed. The Board of Directors may redeem all of the Rights at a pri ce of $0.001 p er Right at any time before any person has become an Acquiring Person. If the Board of Directors redeems any Rights, it must redeem all of the Rights. Once the Rights are redeemed, the only right of the holders of Rights will be to receive the redemption price per Right. The redemption price will be subject to adjustment. The “Distribution Date” generally means the earlier of: • the close of business on the 10 th business day after the date of the first public announcement that a person or any of its affiliates and associates has become an “Acquiring Person,” as defined below, and • the close of business on the 10 th business day (or such later day as may be designated by the Board of Directors before any person has become an Acquiring Person) after the date of the commencement of a tender or exchange offer by any person which would, if consummated, result in such person becoming an Acquiring Person. An “Acquiring Person” generally means any person who or which, together with all affiliates and associates of such person obtains beneficial ownership of 10% or more of shares of the Company’s common stock, with certain exceptions, including that an Acquiring Person does not include the Company, any subsidiary of the Company, any employee benefit plan of the Company or any subsidiary of the Company, any entity or trustee holding the Company’s common stock for or pursuant to the terms of any such plan or for the purpose of funding any such plan or other benefits for employees of the Company or of any subsidiary of the Company or any passive investor. A passive investor generally means any person beneficially owning shares of the Company’s common stock without a plan or an intent to seek control of or influence the Company. The Rights Agreement also provides that any person that would otherwise be deemed an Acquiring Person as of the date of the adoption of the Rights Agreement will be exempted but only for so long as it does not acquire, without the prior approval of the Board, beneficial ownership of any additional common stock of the Company following the adoption of the Rights Agreement. The value of one one-thousandth interest in a share of Preferred Stock should approximate the value of one share of Common Stock, subject to adjustment. Each one one-thousandth of a share of Preferred Stock, if issued: • will not be redeemable, • will entitle holders to quarterly dividend payments of $0.01 per share, or an amount equal to the dividend paid on one share of Common Stock, whichever is greater, • will entitle holders upon liquidation either to receive $1.00 per share or an amount equal to the payment made on one share of Common Stock, whichever is greater, • will have the same voting power as one share of Common Stock, • if shares of the Common Stock are exchanged via merger, consolidation, or a similar transaction, will entitle holders to a per share payment equal to the payment made on one share of Common Stock. Consequences of a Person or Group Becoming an Acquiring Person Flip in. Subject to the Company’s exchange rights, described below, at any time after any person has become an Acquiring Person, each holder of a Right (other than an Acquiring Person, its affiliates and associates) will be entitled to purchase for each Right held, at the Purchase Price, a number of shares of the Company’s common stock having a market value of twice the Purchase Price. Exchange. At any time on or after any person has become an Acquiring Person (but before any person becomes the beneficial owner of 50% or more of the outstanding shares of the Company's common stock or the occurrence of any of the events described in the next paragraph), the Board of Directors may exchange all or part of the Rights (other than Rights beneficially owned by an Acquiring Person, its affiliates and associates) for shares of the Company’s common stock at an exchange ratio of one share of the Company’s common stock per Right. Flip over. If, after any person has become an Acquiring Person, (1) the Company is involved in a merger or other business combination in which the Company is not the surviving corporation or its common stock is exchanged for other securities or assets or (2) the Company and/or one or more of its subsidiaries sell or otherwise transfer assets or earning power aggregating more than 50% of the assets or earning power of the Company and its subsidiaries, taken as a whole, then each Right (other than Rights beneficially owned by an Acquiring Person, its affiliates and associates) will entitle the holder to purchase for each Right held, for the Purchase Price, a number of shares of common stock of the other party to such business combination or sale (or in certain circumstances, an affiliate) having a market value of twice the Purchase Price. Warrants In connection with its participation in the PSP agreement with the Treasury, the Company is obligated to issue to Treasury warrants pursuant to a warrant agreement to purchase up to 500,150 shares of the Company’s common stock at a strike price of $14.08 pe r share (the closing price for the shares of the Company's common stock on April 9, 2020). The warrant agreement sets out the Company’s obligations to issue warrants in connection with disbursements under the PSP and to file a resale shelf registration statement for the warrants and the underlying shares of common stock. The Company has also granted the Treasury certain demand and piggyback registration rights with respect to the warrants and the underlying common stock. The warrants will include adjustments for below market issuances, payment of dividends and other customary anti-dilution provisions. The warrants will be transferable and have no voting rights. The warrants will expire in five years from the date of issuance and, at the Company’s option, may be settled on a “net cash” or “net shares” basis. Refer to Note 2, Impact of COVID-19, for further information on the PSP agreement with Treasury. As of June 30, 2020, the Company received total proceeds of $301.3 million , representing 3 of the 4 installments of funding under the PSP, in exchange for which the Company issued to Treasury $60.4 million in 10-year notes and warrants to purchase 428,829 sha res of the Company's common stock, representing less than 1% of the outstanding shares of the Company's common stock as of July 15, 2020.

Basis of Presentation (Policies

Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of accounting	The accompanying unaudited condensed financial statements include the accounts of Spirit Airlines, Inc. (the "Company"). These unaudited condensed financial statements reflect all normal recurring adjustments which management believes are necessary to fairly present the financial position, results of operations and cash flows of the Company for the respective periods presented. Certain information and footnote disclosures normally included in the audited annual financial statements prepared in accordance with U.S. generally accepted accounting principles ("GAAP") have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission for Form 10-Q. These unaudited interim condensed financial statements should be read in conjunction with the audited financial statements of the Company and notes thereto included in the Company's Annual Report on Form 10-K/A for the year ended December 31, 2019 filed with the Securities and Exchange Commission on April 16, 2020.
Use of estimates	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect both the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from these estimates.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements Accounting for Credit Losses In June 2016, the FASB issued ASU No. 2016-13 Cloud Computing Arrangements

Revenue (Tables)

Revenue (Tables)	6 Months Ended
	Jun. 30, 2020
Revenue from Contract with Customer [Abstract]
Schedule of Revenue Disaggregation	The following table shows disaggregated operating revenues for the three and six months ended June 30, 2020 and June 30, 2019. Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands) Operating revenues: Fare $ 63,769 $ 515,696 $ 385,216 $ 932,041 Non-fare 67,048 478,734 499,151 900,454 Total passenger revenues 130,817 994,430 884,367 1,832,495 Other 7,712 18,526 25,243 36,257 Total operating revenues $ 138,529 $ 1,012,956 $ 909,610 $ 1,868,752 Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands) DOT—Domestic $ 134,373 $ 890,388 $ 832,293 $ 1,644,502 DOT—Latin America 4,156 122,568 77,317 224,250 Total $ 138,529 $ 1,012,956 $ 909,610 $ 1,868,752

Earnings per Share (Tables)

Earnings per Share (Tables)	6 Months Ended
	Jun. 30, 2020
Earnings Per Share [Abstract]
Computation of basic and diluted earnings per common share	The following table sets forth the computation of basic and diluted earnings (loss) per common share: Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands, except per share amounts) Numerator Net income (loss) $ (144,428) $ 114,501 $ (172,256) $ 170,577 Denominator Weighted-average shares outstanding, basic 79,601 68,439 74,061 68,410 Effect of dilutive stock awards — 181 — 158 Adjusted weighted-average shares outstanding, diluted 79,601 68,620 74,061 68,568 Earnings (loss) per share Basic earnings (loss) per common share $ (1.81) $ 1.67 $ (2.33) $ 2.49 Diluted earnings (loss) per common share $ (1.81) $ 1.67 $ (2.33) $ 2.49 Anti-dilutive weighted-average shares 565 127 524 143

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	6 Months Ended
	Jun. 30, 2020
Payables and Accruals [Abstract]
Accrued liabilities included in other current liabilities	Other current liabilities as of June 30, 2020 and December 31, 2019 consist of the following: June 30, 2020 December 31, 2019 (in thousands) Salaries, wages and benefits $ 92,056 $ 89,163 Airport obligations 37,309 80,134 Federal excise and other passenger taxes and fees payable 22,947 65,312 Aircraft maintenance 21,615 38,099 Aircraft and facility lease obligations 21,163 20,656 Interest payable 17,871 16,941 Fuel 5,259 28,510 Other 28,793 34,706 Other current liabilities $ 247,013 $ 373,521

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2020
Leases [Abstract]
Schedule of Operating Lease Maturities	The following table provides details of the Company's future minimum lease payments under finance lease liabilities and operating lease liabilities recorded on the Company's condensed balance sheets as of June 30, 2020. The table does not include commitments that are contingent on events or other factors that are currently uncertain or unknown. Finance Leases Operating Leases Aircraft and Spare Engine Leases Property Facility Leases Other Total (in thousands) remainder of 2020 $ 381 $ 102,077 $ 2,237 $ 228 $ 104,923 2021 753 204,153 4,552 — 209,458 2022 725 205,231 4,262 — 210,218 2023 349 192,586 3,260 — 196,195 2024 98 170,524 2,722 — 173,344 2025 and thereafter — 1,065,928 144,127 — 1,210,055 Total minimum lease payments $ 2,306 $ 1,940,499 $ 161,160 $ 228 $ 2,104,193 Less amount representing interest 192 568,343 135,335 3 703,873 Present value of minimum lease payments $ 2,114 $ 1,372,156 $ 25,825 $ 225 $ 1,400,320 Less current portion 658 125,219 3,092 225 129,194 Long-term portion $ 1,456 $ 1,246,937 $ 22,733 $ — $ 1,271,126
Schedule of Finance Lease Maturities	The following table provides details of the Company's future minimum lease payments under finance lease liabilities and operating lease liabilities recorded on the Company's condensed balance sheets as of June 30, 2020. The table does not include commitments that are contingent on events or other factors that are currently uncertain or unknown. Finance Leases Operating Leases Aircraft and Spare Engine Leases Property Facility Leases Other Total (in thousands) remainder of 2020 $ 381 $ 102,077 $ 2,237 $ 228 $ 104,923 2021 753 204,153 4,552 — 209,458 2022 725 205,231 4,262 — 210,218 2023 349 192,586 3,260 — 196,195 2024 98 170,524 2,722 — 173,344 2025 and thereafter — 1,065,928 144,127 — 1,210,055 Total minimum lease payments $ 2,306 $ 1,940,499 $ 161,160 $ 228 $ 2,104,193 Less amount representing interest 192 568,343 135,335 3 703,873 Present value of minimum lease payments $ 2,114 $ 1,372,156 $ 25,825 $ 225 $ 1,400,320 Less current portion 658 125,219 3,092 225 129,194 Long-term portion $ 1,456 $ 1,246,937 $ 22,733 $ — $ 1,271,126
Schedule of Lease Cost	The table below presents information for lease costs related to the Company's finance and operating leases: Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands) Finance lease cost Amortization of leased assets $ 135 $ 519 $ 270 $ 728 Interest of lease liabilities 26 309 139 339 Operating lease cost Operating lease cost (1) 51,006 48,639 98,223 98,353 Short-term lease cost (1) 6,884 3,509 13,598 6,958 Variable lease cost (1) 25,568 31,653 55,383 59,770 Total lease cost $ 83,619 $ 84,629 $ 167,613 $ 166,148 (1) Expenses are classified within aircraft rent and landing fees and other rents on the Company's condensed statements of operations. The table below presents lease terms and discount rates related to the Company's finance and operating leases: June 30, 2020 June 30, 2019 Weighted-average remaining lease term Operating leases 13.1 years 9.8 years Finance leases 3.1 years 0.8 years Weighted-average discount rate Operating leases 6.07 % 6.52 % Finance leases 5.56 % 3.93 %

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Employee groups and status of the collective bargaining agreements	The table below sets forth the Company's employee groups and status of the collective bargaining agreements as of June 30, 2020. Employee Groups Representative Amendable Date Percentage of Workforce Pilots Air Line Pilots Association, International ("ALPA") February 2023 28% Flight Attendants Association of Flight Attendants ("AFA-CWA") May 2021 46% Dispatchers Professional Airline Flight Control Association ("PAFCA") October 2023 1% Ramp Service Agents International Association of Machinists and Aerospace Workers ("IAMAW") June 2020 3% Passenger Service Agents Transport Workers Union of America ("TWU") NA 3%

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2020
Fair Value Disclosures [Abstract]
Carrying amount and estimated fair value, long-term debt	The carrying amounts and estimated fair values of the Company's long-term debt at June 30, 2020 and December 31, 2019 were as follows: June 30, 2020 December 31, 2019 Fair Value Level Hierarchy Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value (in millions) Fixed-rate senior term loans $ 279.4 $ 262.8 $ 296.1 $ 296.4 Level 3 Fixed-rate term loans 992.2 976.8 778.2 823.6 Level 3 Unsecured term loans 60.4 60.4 — — Level 3 2015-1 EETC Class A 333.5 321.9 348.6 372.2 Level 2 2015-1 EETC Class B 68.0 59.3 72.0 74.5 Level 2 2015-1 EETC Class C 92.4 65.8 98.1 100.5 Level 2 2017-1 EETC Class AA 221.4 208.1 228.4 237.0 Level 2 2017-1 EETC Class A 73.8 61.8 76.1 78.8 Level 2 2017-1 EETC Class B 65.6 51.8 70.6 72.0 Level 2 2017-1 EETC Class C 85.5 60.5 85.5 88.0 Level 2 Convertible debt 101.4 264.1 — — Level 2 Revolving credit facilities 291.2 291.2 160.0 160.0 Level 3 Total long-term debt $ 2,664.8 $ 2,684.5 $ 2,213.6 $ 2,303.0
Schedule of assets and liabilities measured at fair value on a recurring basis	Assets and liabilities measured at gross fair value on a recurring basis are summarized below: Fair Value Measurements as of June 30, ,2020 Total Level Level Level (in millions) Cash and cash equivalents $ 1,127.5 $ 1,127.5 $ — $ — Restricted cash 30.0 30.0 — — Short-term investment securities 106.3 106.3 — — Assets held for sale 2.3 — — 2.3 Total assets $ 1,266.1 $ 1,263.8 $ — $ 2.3 Total liabilities $ — $ — $ — $ — Fair Value Measurements as of December 31, 2019 Total Level Level Level (in millions) Cash and cash equivalents $ 979.0 $ 979.0 $ — $ — Short-term investment securities 105.3 105.3 — — Assets held for sale 2.3 2.3 Total assets $ 1,086.6 $ 1,084.3 $ — $ 2.3 Total liabilities $ — $ — $ — $ —
Schedule of assets held for sale activity	Assets Held for Sale Activity for the Six Months Ended June 30, 2020 (in millions) Balance at December 31, 2019 $ 2.3 Purchases — Sales — Total realized or unrealized gains (losses) included in earnings, net $ — Balance at March 31, 2020 $ 2.3 Purchases — Sales — Total realized or unrealized gains (losses) included in earnings, net — Balance at June 30, 2020 $ 2.3

Debt and Other Obligations (Tab

Debt and Other Obligations (Tables)	6 Months Ended
	Jun. 30, 2020
Debt Disclosure [Abstract]
Schedule of long-term debt	Long-term debt is comprised of the following: As of As of June 30, 2020 December 31, 2019 June 30, 2020 December 31, 2019 (in millions) (weighted-average interest rates) Fixed-rate senior term loans due through 2027 $ 279.4 $ 296.1 3.55 % 4.02 % Fixed-rate loans due through 2031 992.2 778.2 3.34 % 3.70 % Unsecured term loans due in 2030 60.4 — 1.00 % N/A Fixed-rate class A 2015-1 EETC due through 2028 333.5 348.6 4.10 % 4.10 % Fixed-rate class B 2015-1 EETC due through 2024 68.0 72.0 4.45 % 4.45 % Fixed-rate class C 2015-1 EETC due through 2023 92.4 98.1 4.93 % 4.93 % Fixed-rate class AA 2017-1 EETC due through 2030 221.4 228.4 3.38 % 3.38 % Fixed-rate class A 2017-1 EETC due through 2030 73.8 76.1 3.65 % 3.65 % Fixed-rate class B 2017-1 EETC due through 2026 65.6 70.6 3.80 % 3.80 % Fixed-rate class C 2017-1 EETC due through 2023 85.5 85.5 5.11 % 5.11 % Convertible debt due in 2025 101.4 — 4.75 % N/A Revolving credit facility due in 2021 111.2 160.0 1.58 % 3.12 % Revolving credit facility due in 2022 180.0 — 2.19 % N/A Long-term debt 2,664.8 2,213.6 Less current maturities 287.8 214.0 Less unamortized discounts, net 44.8 40.4 Total $ 2,332.2 $ 1,959.2
Schedule of maturities of long-term debt	At June 30, 2020, long-term debt principal payments for the next five years and thereafter are as follows: June 30, 2020 (in millions) remainder of 2020 $ 110.2 2021 278.3 2022 365.6 2023 329.8 2024 215.1 2025 and beyond 1,365.8 Total debt principal payments $ 2,664.8
Schedule of interest expense, long-term debt	Interest expense related to long-term debt and finance leases consists of the following: Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 (in thousands) Fixed-rate senior term loans $ 2,601 $ 3,878 $ 5,414 $ 7,823 Fixed-rate junior term loans — 489 — 1,012 Fixed-rate term loans 8,210 6,432 15,823 12,634 Unsecured term loans 57 — 57 — Class A 2015-1 EETC 3,403 3,709 6,952 7,547 Class B 2015-1 EETC 752 841 1,548 1,721 Class C 2015-1 EETC 1,138 1,280 2,347 2,615 Class AA 2017-1 EETC 1,868 1,997 3,755 3,986 Class A 2017-1 EETC 673 720 1,354 1,437 Class B 2017-1 EETC 623 737 1,267 1,491 Class C 2017-1 EETC 1,092 1,092 2,184 2,171 Convertible debt (1) 3,138 — 3,138 — Revolving credit facilities 1,456 1,559 2,614 2,973 Amortization of deferred financing costs 2,526 2,177 4,632 4,369 Commitment and other fees 228 46 445 119 Finance leases 27 309 140 339 Total $ 27,792 $ 25,266 $ 51,670 $ 50,237 (1) Includes $2.0 million of accretion and $1.1 million of interest expense for the three and six months ended June 30, 2020.

Impact of COVID-19 - Supporting

Impact of COVID-19 - Supporting Communities Narrative (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2020USD ($)flights
Unusual or Infrequent Items, or Both [Abstract]
Number of stranded travelers provided flights due to COVID-19	18
Number of flights provided to stranded travelers due to COVID-19 | flights	140
Flight vouchers pledged to minority organizations due to COVID-19	$ 250

Impact of COVID-19 - Capacity R

Impact of COVID-19 - Capacity Reductions Narrative (Details)	1 Months Ended
	Sep. 30, 2020	Aug. 31, 2020	Jul. 31, 2020	Jun. 30, 2020	May 31, 2020	Apr. 30, 2020
Unusual or Infrequent Item, or Both [Line Items]
Initial capacity reduction from original plan due to COVID-19				95.00%
Capacity reduction in current year compared to prior year				79.00%	93.90%	76.20%
Forecast
Unusual or Infrequent Item, or Both [Line Items]
Capacity reduction in current year compared to prior year	45.00%	35.00%	18.00%

Impact of COVID-19 - CARES Act

Impact of COVID-19 - CARES Act Narrative (Details)	Jul. 31, 2020USD ($)shares	Apr. 29, 2020USD ($)	Apr. 20, 2020USD ($)$ / sharesshares	Jun. 30, 2020USD ($)installmentshares	Jun. 30, 2020USD ($)installmentshares	Jun. 30, 2019USD ($)	Dec. 31, 2020USD ($)	Jun. 30, 2020USD ($)installmentshares	Jun. 30, 2019USD ($)
Unusual or Infrequent Item, or Both [Line Items]
Maximum expected proceeds to be received from Payroll Support Program			$ 334,700,000
Shares of common stock subject to warrants issued to the United States Treasury (in shares) | shares			500,150	428,829	428,829			428,829
Strike price (USD per share) | $ / shares			$ 14.08
Proceeds from Payroll Support Program				$ 301,300,000
Special credits					$ (151,911,000)	$ 0		$ (151,911,000)	$ 0
Expected maximum availability from CARES Act Loan Program		$ 741,000,000
Employee tax credits due to COVID-19								28,000,000
Tax loss carrybacks due to COVID-19								140,800,000
Federal fuel tax savings due to COVID-19								800,000
Additional liquidity expected due to deferred payment of employer portion of social security taxes from CARES Act								24,000,000
Deferred payment of employer portion of social security taxes from CARES Act				$ 10,000,000	$ 10,000,000			$ 10,000,000
Payroll Support Program
Unusual or Infrequent Item, or Both [Line Items]
Number of installments received for Payroll Support Program | installment				3	3			3
Total number of Payroll Support Program installments | installment				4	4			4
CARES Act
Unusual or Infrequent Item, or Both [Line Items]
Adjustments to additional paid in capital, warrant Issued					$ 2,500,000
Amount recorded to deferred payroll liability for unused PSP proceeds due to COVID-19					237,900,000			$ 238,400,000
Special credits					123,900,000			123,900,000
Payroll Support Program, Low-Interest Loan
Unusual or Infrequent Item, or Both [Line Items]
Number of warrants issued as a percent of outstanding common stock		1.00%
Notes Payable To United States Treasury
Unusual or Infrequent Item, or Both [Line Items]
Principal amount				$ 60,400,000	60,400,000			60,400,000
Term				10 years
Notes Payable To United States Treasury | Payroll Support Program, Low-Interest Loan
Unusual or Infrequent Item, or Both [Line Items]
Principal amount			$ 70,400,000	$ 60,400,000	$ 60,400,000			$ 60,400,000
Term			10 years
Forecast
Unusual or Infrequent Item, or Both [Line Items]
Shares of common stock subject to warrants issued to the United States Treasury (in shares) | shares	71,321
Proceeds from Payroll Support Program	$ 33,400,000
Employee tax credits due to COVID-19							$ 10,000,000
Federal fuel tax savings due to COVID-19							$ 5,000,000
Forecast | Payroll Support Program, Low-Interest Loan
Unusual or Infrequent Item, or Both [Line Items]
Term	10 years
Forecast | Notes Payable To United States Treasury
Unusual or Infrequent Item, or Both [Line Items]
Principal amount	$ 10,000,000

Impact of COVID-19 - Income Tax

Impact of COVID-19 - Income Taxes Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Unusual or Infrequent Item, or Both [Line Items]
Effective income tax rate	32.00%	22.90%	40.00%	22.70%
Effective income tax rate with discrete income tax benefit removed			20.90%
CARES Act
Unusual or Infrequent Item, or Both [Line Items]
Discrete income tax benefit due to CARES Act			$ 54,900

Impact of COVID-19 - Balance Sh

Impact of COVID-19 - Balance Sheet, Cash Flow and Liquidity Narrative (Details)	May 12, 2020USD ($)$ / sharesshares	Jun. 30, 2020USD ($)aircraft	Jun. 30, 2019USD ($)	Jun. 30, 2020USD ($)aircraft	Jun. 30, 2019USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Mar. 31, 2021USD ($)	Mar. 31, 2020USD ($)	Mar. 30, 2020USD ($)	Mar. 29, 2020$ / shares	Dec. 31, 2018USD ($)
Unusual or Infrequent Item, or Both [Line Items]
Cash, cash equivalents and short-term investments		$ 1,233,800,000		$ 1,233,800,000
Long-term debt		2,664,800,000		$ 2,664,800,000
Equity component value of convertible debt issuance, net		$ 55,590,000
Purchase price (USD per share) | $ / shares												$ 60
Payments of stock issuance costs	$ 8,900,000
Number of aircraft delivered | aircraft				9
Number of aircraft to be delivered, remainder of fiscal year | aircraft		3		3
Number of aircraft to be delivered, 2021 | aircraft		16		16
Maintenance, materials and repairs		$ 19,227,000	$ 34,688,000	$ 53,303,000	$ 66,292,000
A-320-Neo
Unusual or Infrequent Item, or Both [Line Items]
Number of aircraft with secured debt financing commitments scheduled for delivery | aircraft		20		20
Public Stock Offering
Unusual or Infrequent Item, or Both [Line Items]
Number of shares sold (in shares) | shares	20,125,000
Consideration received on sale of shares	$ 192,400,000
Purchase price (USD per share) | $ / shares	$ 10
Over-Allotment Option
Unusual or Infrequent Item, or Both [Line Items]
Number of shares sold (in shares) | shares	2,625,000
2022 Revolving Credit Facility | Line of Credit | Revolving Credit Facility
Unusual or Infrequent Item, or Both [Line Items]
Line of credit facility, maximum borrowing capacity		$ 180,000,000		$ 180,000,000						$ 110,000,000	$ 110,000,000
Proceeds from revolving credit facility				180,000,000
4.75% Convertible Senior Notes | Convertible debt
Unusual or Infrequent Item, or Both [Line Items]
Principal amount	$ 175,000,000
Stated interest rate	4.75%
Proceeds from issuance of convertible debt				168,300,000
Payments of financing costs				6,700,000
Long-term debt		95,600,000		95,600,000
Debt issuance costs		3,800,000		3,800,000
Equity component value of convertible debt issuance, net		72,700,000
Common stock and warrants issuance costs				2,900,000
2020 Revolving Credit Facility | Line of Credit | Revolving Credit Facility
Unusual or Infrequent Item, or Both [Line Items]
Line of credit facility, maximum borrowing capacity													$ 160,000,000
Proceeds from revolving credit facility								$ 160,000,000
Revolving credit facility due in 2021 | Line of Credit | Revolving Credit Facility
Unusual or Infrequent Item, or Both [Line Items]
Line of credit facility, maximum borrowing capacity		$ 111,200,000		111,200,000
Proceeds from revolving credit facility				111,200,000
Repayments of lines of credit				$ 48,800,000
Subsequent Event | 2020 Revolving Credit Facility | Line of Credit | Revolving Credit Facility
Unusual or Infrequent Item, or Both [Line Items]
Line of credit facility, maximum borrowing capacity									$ 54,000,000
Subsequent Event | Scenario, Plan
Unusual or Infrequent Item, or Both [Line Items]
Reduction in planned capital spending due to COVID-19						$ 50,000,000
Reduction in planned heavy maintenance events due to COVID-19						$ 20,000,000
Subsequent Event | Scenario, Plan | Minimum
Unusual or Infrequent Item, or Both [Line Items]
Reduction in planned non-fuel operating costs due to COVID-19							$ 20,000,000
Subsequent Event | Scenario, Plan | Maximum
Unusual or Infrequent Item, or Both [Line Items]
Reduction in planned non-fuel operating costs due to COVID-19							$ 30,000,000

Recent Accounting Developments

Recent Accounting Developments - Narrative (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member	us-gaap:AccountingStandardsUpdate201613Member	us-gaap:AccountingStandardsUpdate201602Member
Change in Accounting Principle, Accounting Standards Update, Transition Option Elected [Extensible List]	save:AccountingStandardsUpdate201613CumulativeEffectPeriodOfAdoption
Retained earnings	$ 1,781,322	$ 1,955,187
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts receivable, allowance for credit loss				$ 1,600
Retained earnings		$ (1,600)

Revenue (Details)

Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Total operating revenues	$ 138,529	$ 1,012,956	$ 909,610	$ 1,868,752
Refunds issued	77,400		121,000
Air traffic liability	452,023		$ 452,023		$ 315,408
Minimum
Disaggregation of Revenue [Line Items]
Credit shell term expiration			60 days
Maximum
Disaggregation of Revenue [Line Items]
Credit shell term expiration			12 months
DOT—Domestic
Disaggregation of Revenue [Line Items]
Total operating revenues	134,373	890,388	$ 832,293	1,644,502
DOT—Latin America
Disaggregation of Revenue [Line Items]
Total operating revenues	4,156	122,568	77,317	224,250
Passenger
Disaggregation of Revenue [Line Items]
Total operating revenues	130,817	994,430	884,367	1,832,495
Fare
Disaggregation of Revenue [Line Items]
Total operating revenues	63,769	515,696	385,216	932,041
Non-fare
Disaggregation of Revenue [Line Items]
Total operating revenues	67,048	478,734	499,151	900,454
Other
Disaggregation of Revenue [Line Items]
Total operating revenues	$ 7,712	$ 18,526	$ 25,243	$ 36,257

Loss on Disposal of Assets (Det

Loss on Disposal of Assets (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Discontinued Operations and Disposal Groups [Abstract]
Loss on disposal of assets	$ 0	$ 1,550,000	$ 0	$ 3,463,000

Special Credits - Narrative (De

Special Credits - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Unusual or Infrequent Item, or Both [Line Items]
Special credits	$ (151,911,000)	$ 0	$ (151,911,000)	$ 0
CARES Act
Unusual or Infrequent Item, or Both [Line Items]
Amount recorded to deferred payroll liability for unused PSP proceeds due to COVID-19	237,900,000		238,400,000
Payments of financing costs	500,000
Special credits	123,900,000		123,900,000
CARES Act Employee Retention Credit
Unusual or Infrequent Item, or Both [Line Items]
Special credits	$ 28,000,000		$ 28,000,000

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Numerator
Net income (loss)	$ (144,428)	$ (27,828)	$ 114,501	$ 56,076	$ (172,256)	$ 170,577
Denominator
Weighted-average shares outstanding, basic (in shares)	79,601		68,439		74,061	68,410
Effect of dilutive stock awards (in shares)	0		181		0	158
Adjusted weighted-average shares outstanding, diluted (in shares)	79,601		68,620		74,061	68,568
Earnings (loss) per share
Basic earnings (loss) per common share (in dollars per share)	$ (1.81)		$ 1.67		$ (2.33)	$ 2.49
Diluted earnings (loss) per common share (in dollars per share)	$ (1.81)		$ 1.67		$ (2.33)	$ 2.49
Anti-dilutive weighted average shares (in shares)	565		127		524	143

Short-term Investment Securit_2

Short-term Investment Securities (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Short-term investment securities	$ 106,298,000		$ 106,298,000		$ 105,321,000
Unrealized gain on short-term investment securities and cash and cash equivalents, net of deferred taxes of $5, $29, $59 and $67	(199,000)	$ 98,000	123,000	$ 228,000
Tax effect of the unrealized gain (loss) on short-term investment securities	(59,000)	29,000	36,000	67,000
Realized gain (loss) on available-for-sale securities	0	$ 0	0	$ 0
Accumulated other comprehensive income (loss)	(495,000)		$ (495,000)		(787,000)
Available-for-sale Securities
Debt Securities, Available-for-sale [Line Items]
Weighted-average fixed rate			1.50%
Accumulated other comprehensive income (loss)	$ 227,000		$ 227,000		$ 104,000

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Salaries, wages and benefits	$ 92,056	$ 89,163
Airport obligations	37,309	80,134
Federal excise and other passenger taxes and fees payable	22,947	65,312
Aircraft maintenance	21,615	38,099
Aircraft and facility lease obligations	21,163	20,656
Interest payable	17,871	16,941
Fuel	5,259	28,510
Other	28,793	34,706
Other current liabilities	$ 247,013	$ 373,521

Leases Narrative (Details)

Leases Narrative (Details)	3 Months Ended	6 Months Ended
	Mar. 31, 2020aircraft	Jun. 30, 2020USD ($)aircraftaircraft_engine	Dec. 31, 2019USD ($)aresidentialUnits
Lessee, Lease, Description [Line Items]
Number of aircraft held		154
Number of spare engines capitalized		16
Area of land | a			8.5
Land | $			$ 41,000,000
Number of residential units | residentialUnits			200
Operating lease not yet commenced, amount | $		$ 2,600,000
Operating lease not yet commenced, amount, year two | $		$ 0
Aircraft
Lessee, Lease, Description [Line Items]
Number of capitalized aircraft or engine purchased off lease		29
A320 Family | Aircraft
Lessee, Lease, Description [Line Items]
Number of aircraft capitalized		99
Airbus A319
Lessee, Lease, Description [Line Items]
Number of aircraft to be purchased from finance lease	2
Aircraft
Lessee, Lease, Description [Line Items]
Number of delivered aircraft financed with debt		6
Number of previously leased aircraft or engine purchased off lease		2
Aircraft | Minimum
Lessee, Lease, Description [Line Items]
Operating leases, term		8 years
Aircraft | Maximum
Lessee, Lease, Description [Line Items]
Operating leases, term		18 years
Aircraft | A320 Family
Lessee, Lease, Description [Line Items]
Number of leased assets financed under operating leases		55
Other Leased Equipment and Property
Lessee, Lease, Description [Line Items]
Operating leases, term			99 years
Area of land | a			2.6
Other Leased Equipment and Property | Maximum
Lessee, Lease, Description [Line Items]
Operating leases, term		99 years
Spare Engines
Lessee, Lease, Description [Line Items]
Number of leased assets financed under operating leases | aircraft_engine		8
Number of spare engines purchased | aircraft_engine		2
Number Of spare engines returned | aircraft_engine		1
Leased Computer And Office Equipment | Minimum
Lessee, Lease, Description [Line Items]
Finance leases, term		4 years
Leased Computer And Office Equipment | Maximum
Lessee, Lease, Description [Line Items]
Finance leases, term		5 years
Third Party Lessor
Lessee, Lease, Description [Line Items]
Number of delivered leased aircraft		3

Leases Finance and Operating Le

Leases Finance and Operating Lease Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Finance Leases
remainder of 2020	$ 381
2021	753
2022	725
2023	349
2024	98
2025 and thereafter	0
Total minimum lease payments	2,306
Less amount representing interest	192
Present value of minimum lease payments	2,114
Less current portion	658
Long-term portion	1,456
Operating Leases
Less current portion	128,536	$ 120,662
Long-term portion	1,269,670	$ 1,218,014
Total Operating and Finance Lease Obligations
remainder of 2020	104,923
2021	209,458
2022	210,218
2023	196,195
2024	173,344
2025 and thereafter	1,210,055
Total minimum lease payments	2,104,193
Less amount representing interest	703,873
Present value of minimum lease payments	1,400,320
Less current portion	129,194
Long-term portion	1,271,126
Aircraft and Spare Engine Leases
Operating Leases
remainder of 2020	102,077
2021	204,153
2022	205,231
2023	192,586
2024	170,524
2025 and thereafter	1,065,928
Total minimum lease payments	1,940,499
Less amount representing interest	568,343
Present value of minimum lease payments	1,372,156
Less current portion	125,219
Long-term portion	1,246,937
Property Facility Leases
Operating Leases
remainder of 2020	2,237
2021	4,552
2022	4,262
2023	3,260
2024	2,722
2025 and thereafter	144,127
Total minimum lease payments	161,160
Less amount representing interest	135,335
Present value of minimum lease payments	25,825
Less current portion	3,092
Long-term portion	22,733
Other
Operating Leases
remainder of 2020	228
2021	0
2022	0
2023	0
2024	0
2025 and thereafter	0
Total minimum lease payments	228
Less amount representing interest	3
Present value of minimum lease payments	225
Less current portion	225
Long-term portion	$ 0

Leases Lease Costs (Details)

Leases Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Finance lease cost
Amortization of leased assets	$ 135	$ 519	$ 270	$ 728
Interest of lease liabilities	26	309	139	339
Operating lease cost
Operating lease cost	51,006	48,639	98,223	98,353
Short-term lease cost	6,884	3,509	13,598	6,958
Variable lease cost	25,568	31,653	55,383	59,770
Total lease cost	$ 83,619	$ 84,629	$ 167,613	$ 166,148

Leases Weighted Average Lease T

Leases Weighted Average Lease Terms and Discount Rates (Details)	Jun. 30, 2020	Jun. 30, 2019
Weighted-average remaining lease term
Operating leases	13 years 1 month 6 days	9 years 9 months 18 days
Finance leases	3 years 1 month 6 days	9 months 18 days
Weighted-average discount rate
Operating leases	6.07%	6.52%
Finance leases	5.56%	3.93%

Commitments and Contingencies -

Commitments and Contingencies - Aircraft-Related Commitments and Financing Arrangements (Details)	6 Months Ended
	Jun. 30, 2020USD ($)aircraftaircraft_engine	Dec. 31, 2021aircraft	Dec. 31, 2019aircraft
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of aircraft delivered | aircraft	9
Number of aircraft to be delivered, remainder of fiscal year | aircraft	3
Number of aircraft to be delivered, 2021 | aircraft	16
Principal And Interest Commitments [Abstract]
Principal and interest commitments related to future secured debt, remainder of fiscal year	$ 900,000
Principal and interest commitments related to future secured debt, 2021	8,500,000
Principal and interest commitments related to future secured debt, 2022	6,500,000
Principal and interest commitments related to future secured debt, 2023	7,000,000
Principal and interest commitments related to future secured debt, 2024	7,100,000
Principal and interest commitments related to future secured debt, 2025 and thereafter	$ 64,700,000
Airbus
Unrecorded Unconditional Purchase Obligation [Line Items]
Future aircraft to be received | aircraft	129
Secured Debt
Interest Commitments
Interest commitments, remainder of 2020	$ 40,700,000
Interest commitments, 2021	76,200,000
Interest commitments, 2022	69,500,000
Interest commitments, 2023	58,900,000
Interest commitments, 2024	47,900,000
Interest commitments, 2025 and thereafter	131,200,000
Unsecured Debt And Convertible Debt
Interest Commitments
Interest commitments, remainder of 2020	4,400,000
Interest commitments, 2021	8,900,000
Interest commitments, 2022	8,900,000
Interest commitments, 2023	8,900,000
Interest commitments, 2024	8,900,000
Interest commitments, 2025 and thereafter	$ 10,700,000
2020 | Airbus
Committed Expenditures
Number of aircraft with secured debt financing commitments scheduled for delivery | aircraft	2
2020-2027 | Airbus
Committed Expenditures
Number of aircraft without secured financing commitments scheduled for delivery | aircraft	127
Aircraft and Related Flight Equipment
Committed Expenditures
Committed expenditures, remainder of 2020	$ 119,000,000
Committed expenditures, 2021	356,400,000
Committed expenditures, 2022	606,100,000
Committed expenditures, 2023	707,600,000
Committed expenditures, 2024	1,073,000,000
Committed expenditures, 2025 and thereafter	3,763,400,000
Non-aircraft Related Commitments
Committed Expenditures
Committed expenditures, remainder of 2020	10,700,000
Committed expenditures, 2021	17,100,000
Committed expenditures, 2022	16,200,000
Committed expenditures, 2023	14,400,000
Committed expenditures, 2024	14,500,000
Committed expenditures, 2025 and thereafter	$ 50,300,000
V2500 SelectTWO Engine | 2020-2023
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of spare aircraft engines ordered | aircraft_engine	1
PurePower PW1100G-JM Engine | 2020-2023
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of spare aircraft engines ordered | aircraft_engine	2
A-320-Neo
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of aircraft ordered | aircraft			100
Number of additional aircraft available for purchase | aircraft			50
Committed Expenditures
Number of aircraft with secured debt financing commitments scheduled for delivery | aircraft	20
A-320-Neo | Third Party Lessor
Unrecorded Unconditional Purchase Obligation [Line Items]
Future aircraft to be received | aircraft	10
A320 Family | Third Party Lessor
Aircraft Rent Commitments For Future Aircraft Deliveries [Abstract]
Operating lease payments expected for aircraft to be delivered, remainder of 2020	$ 0
Operating lease payments expected for aircraft to be delivered, 2021	18,200,000
Operating lease payments expected for aircraft to be delivered, 2022	33,400,000
Operating lease payments expected for aircraft to be delivered, 2023	33,400,000
Operating lease payments expected for aircraft to be delivered, 2024	33,400,000
Operating lease payments expected for aircraft to be delivered, 2025 and thereafter	$ 282,500,000
A320 and A321
Aircraft Rent Commitments For Future Aircraft Deliveries [Abstract]
Number of delivered aircraft with secured debt financing commitments | aircraft	70
Forecast | A-320-Neo
Committed Expenditures
Number of aircraft with secured debt financing commitments scheduled for delivery | aircraft		43

Commitments and Contingencies_2

Commitments and Contingencies - Credit Card Processing Arrangements (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Restricted cash holdbacks	$ 0	$ 0
Maximum Potential Exposure to Cash Holdbacks from Credit Card Processors	$ 417,300,000	$ 342,300,000

Commitments and Contingencies_3

Commitments and Contingencies - Employees (Details) $ in Millions	6 Months Ended
	Jun. 30, 2020USD ($)employee_group	Dec. 31, 2019USD ($)
Health Insurance
Liability for Claims and Claims Adjustment Expense [Line Items]
Accrued health care claims | $	$ 5.2	$ 5.2
Unionized Employees Concentration Risk | Number of Employees, Total
Concentration Risk [Line Items]
Number of union-represented employee groups | employee_group	5
Company's employees covered under collective bargaining agreements (as a percent)	81.00%
Unionized Employees Concentration Risk | Number of Employees, Total | Air Line Pilots Association, International ("ALPA")
Concentration Risk [Line Items]
Company's employees covered under collective bargaining agreements (as a percent)	28.00%
Unionized Employees Concentration Risk | Number of Employees, Total | Association of Flight Attendants ("AFA-CWA")
Concentration Risk [Line Items]
Company's employees covered under collective bargaining agreements (as a percent)	46.00%
Unionized Employees Concentration Risk | Number of Employees, Total | Professional Airline Flight Control Association ("PAFCA")
Concentration Risk [Line Items]
Company's employees covered under collective bargaining agreements (as a percent)	1.00%
Unionized Employees Concentration Risk | Number of Employees, Total | International Association of Machinists and Aerospace Workers ("IAMAW")
Concentration Risk [Line Items]
Company's employees covered under collective bargaining agreements (as a percent)	3.00%
Unionized Employees Concentration Risk | Number of Employees, Total | Transport Workers Union of America ("TWU")
Concentration Risk [Line Items]
Company's employees covered under collective bargaining agreements (as a percent)	3.00%

Fair Value Measurements - Long-

Fair Value Measurements - Long-term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Carrying Value	$ 2,664.8	$ 2,213.6
Fixed-rate senior term loans
Debt Instrument [Line Items]
Carrying Value	279.4	296.1
Fixed-rate term loans
Debt Instrument [Line Items]
Carrying Value	992.2	778.2
Unsecured term loans
Debt Instrument [Line Items]
Carrying Value	60.4	0
2015-1 EETC Class A
Debt Instrument [Line Items]
Carrying Value	333.5	348.6
2015-1 EETC Class B
Debt Instrument [Line Items]
Carrying Value	68	72
2015-1 EETC Class C
Debt Instrument [Line Items]
Carrying Value	92.4	98.1
2017-1 EETC Class AA
Debt Instrument [Line Items]
Carrying Value	221.4	228.4
2017-1 EETC Class A
Debt Instrument [Line Items]
Carrying Value	73.8	76.1
2017-1 EETC Class B
Debt Instrument [Line Items]
Carrying Value	65.6	70.6
2017-1 EETC Class C
Debt Instrument [Line Items]
Carrying Value	85.5	85.5
Convertible debt
Debt Instrument [Line Items]
Carrying Value	101.4	0
Revolving Credit Facility
Debt Instrument [Line Items]
Carrying Value	291.2
2020 Revolving Credit Facility
Debt Instrument [Line Items]
Carrying Value		160
Estimated Fair Value
Debt Instrument [Line Items]
Estimated Fair Value	2,684.5	2,303
Estimated Fair Value | Level 3 | Fixed-rate senior term loans
Debt Instrument [Line Items]
Estimated Fair Value	262.8	296.4
Estimated Fair Value | Level 3 | Fixed-rate term loans
Debt Instrument [Line Items]
Estimated Fair Value	976.8	823.6
Estimated Fair Value | Level 3 | Unsecured term loans
Debt Instrument [Line Items]
Estimated Fair Value	60.4	0
Estimated Fair Value | Level 3 | Revolving Credit Facility
Debt Instrument [Line Items]
Estimated Fair Value	291.2
Estimated Fair Value | Level 3 | 2020 Revolving Credit Facility
Debt Instrument [Line Items]
Estimated Fair Value		160
Estimated Fair Value | Level 2 | 2015-1 EETC Class A
Debt Instrument [Line Items]
Estimated Fair Value	321.9	372.2
Estimated Fair Value | Level 2 | 2015-1 EETC Class B
Debt Instrument [Line Items]
Estimated Fair Value	59.3	74.5
Estimated Fair Value | Level 2 | 2015-1 EETC Class C
Debt Instrument [Line Items]
Estimated Fair Value	65.8	100.5
Estimated Fair Value | Level 2 | 2017-1 EETC Class AA
Debt Instrument [Line Items]
Estimated Fair Value	208.1	237
Estimated Fair Value | Level 2 | 2017-1 EETC Class A
Debt Instrument [Line Items]
Estimated Fair Value	61.8	78.8
Estimated Fair Value | Level 2 | 2017-1 EETC Class B
Debt Instrument [Line Items]
Estimated Fair Value	51.8	72
Estimated Fair Value | Level 2 | 2017-1 EETC Class C
Debt Instrument [Line Items]
Estimated Fair Value	60.5	88
Estimated Fair Value | Level 2 | Convertible debt
Debt Instrument [Line Items]
Estimated Fair Value	$ 264.1	$ 0

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($)	6 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Standby Letters of Credit | Line of Credit
Long Lived Assets Held-for-sale [Line Items]
Line of credit facility, maximum borrowing capacity	$ 30,000,000
Proceeds from revolving credit facility	23,100,000
Fair Value, Recurring
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale	$ 2,300,000	$ 2,300,000

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 1,127,500	$ 979,000
Restricted cash	30,000
Short-term investment securities	106,300	105,300
Assets held for sale	2,300	2,300
Total assets	1,266,100	1,086,600
Total liabilities	0	0
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	1,127,500	979,000
Restricted cash	30,000
Short-term investment securities	106,300	105,300
Assets held for sale	0
Total assets	1,263,800	1,084,300
Total liabilities	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Restricted cash	0
Short-term investment securities	0	0
Assets held for sale	0
Total assets	0	0
Total liabilities	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Restricted cash	0
Short-term investment securities	0	0
Assets held for sale	2,300	2,300
Total assets	2,300	2,300
Total liabilities	$ 0	$ 0

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Assets Held For Sale Activity (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2020	Mar. 31, 2020
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	$ 2.3	$ 2.3
Purchases	0	0
Sales	0	0
Total realized or unrealized gains (losses) included in earnings, net	0	0
Ending balance	$ 2.3	$ 2.3

Debt and Other Obligations - Na

Debt and Other Obligations - Narrative (Details)	Jul. 31, 2020USD ($)	May 12, 2020USD ($)$ / sharesshares	Apr. 20, 2020USD ($)	Mar. 30, 2020USD ($)	Jun. 30, 2020USD ($)aircraft	Jun. 30, 2020USD ($)aircraft	Jun. 30, 2020USD ($)aircraft	Jun. 30, 2019USD ($)	Jun. 30, 2020USD ($)aircraft	Jun. 30, 2019USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2021aircraft	Mar. 31, 2020USD ($)	Dec. 31, 2018USD ($)
Debt Instrument [Line Items]
Proceeds from Payroll Support Program						$ 301,300,000
Maximum expected proceeds to be received from Payroll Support Program			$ 334,700,000
Long-term debt					$ 2,664,800,000	2,664,800,000	$ 2,664,800,000		$ 2,664,800,000		$ 2,213,600,000
Long-term debt					2,664,800,000	2,664,800,000	2,664,800,000		2,664,800,000
Equity component value of convertible debt issuance, net							55,590,000
Repayments of long-term debt							106,900,000	$ 47,900,000	149,400,000	$ 85,800,000
Accretion of convertible debt									2,029,000	$ 0
CARES Act
Debt Instrument [Line Items]
Payments of financing costs							500,000
Forecast
Debt Instrument [Line Items]
Proceeds from Payroll Support Program	$ 33,400,000
Payroll Support Program, Low-Interest Loan | Forecast
Debt Instrument [Line Items]
Term	10 years
Fixed-rate term loans
Debt Instrument [Line Items]
Principal amount					249,000,000	249,000,000	249,000,000		249,000,000
Long-term debt					992,200,000	992,200,000	992,200,000		992,200,000		778,200,000
Notes Payable To United States Treasury
Debt Instrument [Line Items]
Principal amount					60,400,000	$ 60,400,000	60,400,000		60,400,000
Term						10 years
Notes Payable To United States Treasury | Forecast
Debt Instrument [Line Items]
Principal amount	$ 10,000,000
Notes Payable To United States Treasury | Payroll Support Program, Low-Interest Loan
Debt Instrument [Line Items]
Principal amount			$ 70,400,000		60,400,000	$ 60,400,000	60,400,000		60,400,000
Term			10 years
Notes Payable To United States Treasury | Payroll Support Program Term Loan | Forecast
Debt Instrument [Line Items]
Principal amount	10,000,000
Notes Payable To United States Treasury | Payroll Support Program
Debt Instrument [Line Items]
Stated interest rate			1.00%
Notes Payable To United States Treasury | Payroll Support Program | Forecast
Debt Instrument [Line Items]
Principal amount	$ 70,400,000
Notes Payable To United States Treasury | Payroll Support Program | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Basis spread on variable rate			2.00%
Unsecured term loans
Debt Instrument [Line Items]
Long-term debt					60,400,000	60,400,000	60,400,000		60,400,000		0
Convertible debt
Debt Instrument [Line Items]
Long-term debt					101,400,000	101,400,000	101,400,000		101,400,000		0
Accretion of convertible debt									2,000,000
Interest expense							1,100,000
Convertible debt | 4.75% Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount		$ 175,000,000
Term		5 years
Stated interest rate		4.75%
Proceeds from issuance of convertible debt									168,300,000
Payments of financing costs									6,700,000
Long-term debt					95,600,000	95,600,000	95,600,000		95,600,000
Debt issuance costs					3,800,000	$ 3,800,000	3,800,000		3,800,000
Equity component value of convertible debt issuance, net							$ 72,700,000
Common stock and warrants issuance costs									$ 2,900,000
Debt instrument, convertible, if-converted value in excess of principal					$ 38,000,000
Convertible debt, conversion price threshold		130.00%
Number of trading days required for conversion price threshold		20 days
Number of consecutive days required for trading days for conversion price threshold		30 days
Number of consecutive business days for conversion price threshold		5 days
Number of consecutive trading days measurement period		5 days
Principal amount portion for trading price threshold		$ 1,000
Trading price threshold per principal amount portion		98.00%
Shares conversion rate per portion of principal amount (in shares) | shares		78.4314
Conversion price (in dollars per share) | $ / shares		$ 12.75
A-320-Neo
Debt Instrument [Line Items]
Number of aircraft with secured debt financing commitments scheduled for delivery | aircraft					20	20	20		20
A-320-Neo | Forecast
Debt Instrument [Line Items]
Number of aircraft with secured debt financing commitments scheduled for delivery | aircraft												43
Fixed-rate term loans | Minimum
Debt Instrument [Line Items]
Long-term debt, term					11 years	11 years	11 years		11 years
Fixed-rate term loans | Maximum
Debt Instrument [Line Items]
Long-term debt, term					12 years	12 years	12 years		12 years
Revolving Credit Facility | Line of Credit
Debt Instrument [Line Items]
Debt covenant, amount of unrestricted cash and cash equivalents and unused commitments on all revolving credit facilities				$ 400,000,000
Debt covenant, maximum amount of unused commitments from 2022 revolving credit facility				$ 200,000,000
Debt covenant, collateral coverage ratio				1
Revolving Credit Facility | Line of Credit | 2022 Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity				$ 110,000,000	$ 180,000,000	$ 180,000,000	$ 180,000,000		$ 180,000,000				$ 110,000,000
Line of credit facility, optional maximum borrowing capacity subject to consent of lenders				$ 350,000,000
Proceeds from revolving credit facility									180,000,000
Revolving Credit Facility | Line of Credit | Revolving credit facility due in 2021
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity					$ 111,200,000	$ 111,200,000	$ 111,200,000		111,200,000
Proceeds from revolving credit facility									$ 111,200,000
Revolving Credit Facility | Line of Credit | 2020 Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity														$ 160,000,000
Proceeds from revolving credit facility											$ 160,000,000
Revolving Credit Facility | Minimum | Line of Credit | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate				0.00%
Revolving Credit Facility | Minimum | Line of Credit | Certain Market Interest Rates
Debt Instrument [Line Items]
Basis spread on variable rate				0.00%
Revolving Credit Facility | Maximum | Line of Credit | London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate				2.00%
Revolving Credit Facility | Maximum | Line of Credit | Certain Market Interest Rates
Debt Instrument [Line Items]
Basis spread on variable rate				1.00%
Airbus | Airbus A320 | Fixed-rate term loans
Debt Instrument [Line Items]
Number of delivered aircraft financed with debt | aircraft									6

Debt and Other Obligations - Sc

Debt and Other Obligations - Schedule of Long-term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt	$ 2,664.8	$ 2,213.6
Current maturities of long-term debt	287.8	214
Less unamortized discounts, net	44.8	40.4
Long-term debt and capital leases, less current maturities	2,332.2	1,959.2
Fixed-rate senior term loans
Debt Instrument [Line Items]
Long-term debt	$ 279.4	$ 296.1
Weighted-average interest rate	3.55%	4.02%
Fixed-rate term loans
Debt Instrument [Line Items]
Long-term debt	$ 992.2	$ 778.2
Weighted-average interest rate	3.34%	3.70%
Unsecured term loans
Debt Instrument [Line Items]
Long-term debt	$ 60.4	$ 0
Weighted-average interest rate	1.00%
2015-1 EETC Class A
Debt Instrument [Line Items]
Long-term debt	$ 333.5	$ 348.6
Weighted-average interest rate	4.10%	4.10%
2015-1 EETC Class B
Debt Instrument [Line Items]
Long-term debt	$ 68	$ 72
Weighted-average interest rate	4.45%	4.45%
2015-1 EETC Class C
Debt Instrument [Line Items]
Long-term debt	$ 92.4	$ 98.1
Weighted-average interest rate	4.93%	4.93%
2017-1 EETC Class AA
Debt Instrument [Line Items]
Long-term debt	$ 221.4	$ 228.4
Weighted-average interest rate	3.38%	3.38%
2017-1 EETC Class A
Debt Instrument [Line Items]
Long-term debt	$ 73.8	$ 76.1
Weighted-average interest rate	3.65%	3.65%
2017-1 EETC Class B
Debt Instrument [Line Items]
Long-term debt	$ 65.6	$ 70.6
Weighted-average interest rate	3.80%	3.80%
2017-1 EETC Class C
Debt Instrument [Line Items]
Long-term debt	$ 85.5	$ 85.5
Weighted-average interest rate	5.11%	5.11%
Convertible debt
Debt Instrument [Line Items]
Long-term debt	$ 101.4	$ 0
Weighted-average interest rate	4.75%
Revolving credit facility due in 2021
Debt Instrument [Line Items]
Long-term debt	$ 111.2
Weighted-average interest rate	1.58%
2020 Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt		$ 160
Weighted-average interest rate		3.12%
Revolving credit facility due in 2022
Debt Instrument [Line Items]
Long-term debt	$ 180	$ 0
Weighted-average interest rate	2.19%

Debt and Other Obligations - Fu

Debt and Other Obligations - Future Maturities (Details) $ in Millions	Jun. 30, 2020USD ($)
Debt Disclosure [Abstract]
remainder of 2020	$ 110.2
2021	278.3
2022	365.6
2023	329.8
2024	215.1
2025 and beyond	1,365.8
Total debt principal payments	$ 2,664.8

Debt and Other Obligations - In

Debt and Other Obligations - Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Debt Instrument [Line Items]
Amortization of deferred financing costs	$ 2,526	$ 2,177	$ 4,632	$ 4,369
Commitment and other fees	228	46	445	119
Total	27,792	25,266	51,670	50,237
Fixed-rate senior term loans
Debt Instrument [Line Items]
Interest expense	2,601	3,878	5,414	7,823
Fixed-rate junior term loans
Debt Instrument [Line Items]
Interest expense	0	489	0	1,012
Fixed-rate term loans
Debt Instrument [Line Items]
Interest expense	8,210	6,432	15,823	12,634
Unsecured term loans
Debt Instrument [Line Items]
Interest expense	57	0	57	0
2015-1 EETC Class A
Debt Instrument [Line Items]
Interest expense	3,403	3,709	6,952	7,547
2015-1 EETC Class B
Debt Instrument [Line Items]
Interest expense	752	841	1,548	1,721
2015-1 EETC Class C
Debt Instrument [Line Items]
Interest expense	1,138	1,280	2,347	2,615
2017-1 EETC Class AA
Debt Instrument [Line Items]
Interest expense	1,868	1,997	3,755	3,986
2017-1 EETC Class A
Debt Instrument [Line Items]
Interest expense	673	720	1,354	1,437
2017-1 EETC Class B
Debt Instrument [Line Items]
Interest expense	623	737	1,267	1,491
2017-1 EETC Class C
Debt Instrument [Line Items]
Interest expense	1,092	1,092	2,184	2,171
Convertible debt
Debt Instrument [Line Items]
Interest expense	3,138	0	3,138	0
Revolving credit facilities
Debt Instrument [Line Items]
Interest expense	1,456	1,559	2,614	2,973
Finance leases
Debt Instrument [Line Items]
Interest expense	$ 27	$ 309	$ 140	$ 339

Equity - Common Stock Offering

Equity - Common Stock Offering Narrative (Details) - USD ($)	May 12, 2020	Jun. 30, 2020	Mar. 29, 2020
Class of Stock [Line Items]
Purchase price (USD per share)			$ 60
Payments of stock issuance costs	$ 8,900,000
Issuance of common stock and warrants, net		$ 194,886,000
Public Stock Offering
Class of Stock [Line Items]
Number of shares sold (in shares)	20,125,000
Purchase price (USD per share)	$ 10
Consideration received on sale of shares	$ 192,400,000
Over-Allotment Option
Class of Stock [Line Items]
Number of shares sold (in shares)	2,625,000
Common Stock
Class of Stock [Line Items]
Issuance of common stock and warrants, net	$ 20,200	$ 20,000

Equity - Preferred Stock and Ma

Equity - Preferred Stock and Material Modifications to Rights of Security Holders Narrative (Details)	Mar. 29, 2020$ / sharesshares
Equity [Abstract]
Dividends, preferred stock purchase right per common stock (in shares) | shares	1
Minimum threshold of outstanding common stock purchased without Board Of Director approval subject to penalty, percentage	10.00%
Purchase price (USD per share)	$ 60
Par value (USD per share)	0.0001
Preferred stock, redemption price per share (USD per share)	$ 0.001
Threshold of shares owned to qualify as Acquiring Person	10.00%
Quarterly dividend rate (USD per share)	$ 0.01
Amount per share received upon liquidation (USD per share)	$ 1
Threshold of shares to qualify as Beneficial Owner	50.00%
Percent of assets or earning power sold or transferred, allowed purchase for each right	50.00%
Preferred Stock, Common Stock Equivalent | shares	0.001

Equity - Warrants (Details)

Equity - Warrants (Details)	Apr. 20, 2020USD ($)$ / sharesshares	Jun. 30, 2020USD ($)installmentshares	Jun. 30, 2020USD ($)installmentshares	Apr. 29, 2020
Class of Warrant or Right [Line Items]
Shares of common stock subject to warrants issued to the United States Treasury (in shares) | shares	500,150	428,829	428,829
Strike price (USD per share) | $ / shares	$ 14.08
Term of warrants	5 years
Proceeds from Payroll Support Program		$ 301,300,000
Payroll Support Program, Low-Interest Loan
Class of Warrant or Right [Line Items]
Number of warrants issued as a percent of outstanding common stock				1.00%
CARES Act
Class of Warrant or Right [Line Items]
Adjustments to additional paid in capital, warrant Issued			$ 2,500,000
Payroll Support Program
Class of Warrant or Right [Line Items]
Number of installments received for Payroll Support Program | installment		3	3
Total number of Payroll Support Program installments | installment		4	4
Notes Payable To United States Treasury
Class of Warrant or Right [Line Items]
Principal amount		$ 60,400,000	$ 60,400,000
Term		10 years
Notes Payable To United States Treasury | Payroll Support Program, Low-Interest Loan
Class of Warrant or Right [Line Items]
Principal amount	$ 70,400,000	$ 60,400,000	$ 60,400,000
Term	10 years