Allegiant Travel (ALGT) 10-K 22 Feb 16 2015 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2015	Feb. 01, 2016	Jun. 30, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	Allegiant Travel CO
Document Type	10-K
Current Fiscal Year End Date	--12-31
Entity Public Float			$ 2,400,000,000
Entity Common Stock, Shares Outstanding		16,799,460
Amendment Flag	false
Entity Central Index Key	1,362,468
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Well Known Seasoned Issuer	Yes
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
CURRENT ASSETS:
Cash and cash equivalents	$ 87,112	$ 89,610
Restricted cash	10,358	12,021
Short-term investments	245,583	269,817
Accounts receivable	15,146	14,216
Expendable parts, supplies and fuel, net	15,583	16,980
Prepaid expenses	18,276	24,306
Deferred income taxes	0	6,271
Other current assets	3,185	406
TOTAL CURRENT ASSETS	395,243	433,627
Property and equipment, net	885,942	738,783
Long-term investments	64,752	57,390
Deposits and other assets	5,725	5,280
TOTAL ASSETS	1,351,662	1,235,080
CURRENT LIABILITIES:
Accounts payable	6,801	13,232
Accrued liabilities	109,462	110,802
Air traffic liability	198,136	185,315
Current maturities of long-term debt, net of related costs	74,069	52,605
TOTAL CURRENT LIABILITIES	388,468	361,954
LONG-TERM DEBT AND OTHER LONG-TERM LIABILITIES:
Long-term debt, net of current maturities and related costs	567,609	536,189
Deferred income taxes	45,580	42,872
TOTAL LIABILITIES	1,001,657	941,015
SHAREHOLDERS' EQUITY:
Common stock, par value $.001, 100,000,000 shares authorized; 22,250,210 and 22,174,241 shares issued; 16,802,897 and 17,413,307 shares outstanding, as of December 31, 2015 and 2014, respectively	22	22
Treasury stock, at cost, 5,447,313 and 4,760,934 shares at December 31, 2015 and 2014, respectively	(453,415)	(325,396)
Additional paid in capital	228,945	221,257
Accumulated other comprehensive income, net	834	1,211
Retained earnings	573,619	395,783
TOTAL ALLEGIANT TRAVEL COMPANY SHAREHOLDERS' EQUITY	350,005	292,877
Noncontrolling interest	0	1,188
TOTAL EQUITY	350,005	294,065
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 1,351,662	$ 1,235,080

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	22,250,210	22,174,241
Common stock, shares outstanding	16,802,897	17,413,307
Treasury stock, shares	5,447,313	4,760,934

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
OPERATING REVENUE:
Scheduled service revenue	$ 735,563	$ 732,020	$ 651,318
Ancillary revenue:
Air-related charges	434,317	331,689	287,857
Third party products	40,177	36,587	37,030
Total ancillary revenue	474,494	368,276	324,887
Fixed fee contract revenue	19,747	17,403	17,462
Other revenue	32,384	19,347	2,483
Total operating revenue	1,262,188	1,137,046	996,150
OPERATING EXPENSES:
Aircraft fuel	278,394	388,216	385,558
Salary and benefits	229,802	193,345	158,627
Station operations	102,294	84,667	78,231
Maintenance and repairs	92,575	86,781	72,818
Sales and marketing	21,349	28,492	21,678
Aircraft lease rentals	2,326	15,945	9,227
Depreciation and amortization	98,097	83,409	69,264
Other	65,649	55,566	46,010
Special charge	0	43,280	0
Total operating expenses	890,486	979,701	841,413
OPERATING INCOME	371,702	157,345	154,737
OTHER (INCOME) EXPENSE:
Interest income	(1,391)	(774)	(1,043)
Interest expense	(26,510)	(21,205)	(9,493)
Other, net	(136)	(217)	(393)
Total other expense	24,983	20,214	8,057
INCOME BEFORE INCOME TAXES	346,719	137,131	146,680
PROVISION FOR INCOME TAXES	126,389	50,828	54,901
NET INCOME	220,330	86,303	91,779
Net loss attributable to noncontrolling interest	(44)	(386)	(494)
NET INCOME ATTRIBUTABLE TO ALLEGIANT TRAVEL COMPANY	$ 220,374	$ 86,689	$ 92,273
Earnings per share to common shareholders:
Basic (in Dollars per share)	$ 12.97	$ 4.87	$ 4.85
Diluted (in Dollars per share)	$ 12.94	$ 4.86	$ 4.82
Shares used for computation:
Basic (in Shares)	16,923	17,729	18,936
Diluted (in Shares)	16,962	17,782	19,050
Cash dividends declared per share:	$ 2.75	$ 2.50	$ 2.25

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 220,330	$ 86,303	$ 91,779
OTHER COMPREHENSIVE INCOME:
Unrealized gain (loss) on available-for-sale securities, net of tax effect of $104, $78 and ($34) for 2015, 2014 and 2013, respectively	(185)	(124)	57
Foreign currency translation adjustment, net of tax effect	226	176	0
Unrealized gain on derivatives, net of tax effect of ($252), ($687) and $- for 2015, 2014 and 2013, respectively	874	1,171	0
Reclassification of derivative gains into Other revenue	(1,292)	0	0
Total other comprehensive (loss) income	(377)	1,223	57
TOTAL COMPREHENSIVE INCOME	219,953	87,526	91,836
Net loss attributable to noncontrolling interest	(44)	(386)	(494)
COMPREHENSIVE INCOME ATTRIBUTABLE TO ALLEGIANT TRAVEL COMPANY	$ 219,997	$ 87,912	$ 92,330

Consolidated Statements of Com6

Consolidated Statements of Comprehensive Income Consolidated Statements of Comprehensive Income - Parenthetical - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income - Parenthetical [Abstract]
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax	$ 104	$ 78	$ (34)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	$ (252)	$ (687)	$ 0

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity Statement - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Treasury Stock	Parent	Noncontrolling Interest
Common stock, shares issued		19,334,000
Common Stock, Value, Issued		$ 22
Additional paid in capital			$ 201,012
Accumulated Other Comprehensive Income (Loss), Net of Tax				$ (69)
Retained Earnings (Accumulated Deficit)					$ 302,325
Treasury Stock, Value						$ (102,829)
Stockholders' Equity Attributable to Parent							$ 400,461
Stockholders' Equity Attributable to Noncontrolling Interest								$ 1,263
Balance at at Dec. 31, 2012	$ 401,724
Stock-based compensation expense	4,430	$ 0	4,430	0	0	0	4,430	0
Issuance of restricted stock		85,000
Exercises of stock options and stock-settled SARs (Shares)		56,000
Exercises of stock options and stock-settled SARs	2,082	$ 0	2,082	0	0	0	2,082	0
Tax benefit from stock based compensation	1,689	0	1,689	0	0	0	1,689	0
Assets sold in acquisition of ownership interest in subsidiary	(1,225)							(1,225)
Assets acquired and services rendered in sale of ownership interest in subsidiary	$ 2,030	$ 0	0	0	0	0	0	2,030
Cancellation of restricted stock		(4,000)
Stock Repurchased During Period, Shares	(927,006)	(927,000)
Shares repurchased by the Company and held as treasury shares	$ (83,462)	$ 0	0	0	0	(83,462)	(83,462)	0
Dividends, Cash	(41,787)	0	0	0	(41,787)	0	(41,787)	0
Unrealized gain on short-term investments, net of tax	57	0	0	57	0	0	57	0
Net income (loss)	91,779	$ 0	0	0	92,273	0	92,273	(494)
Common stock, shares issued		18,544,000
Common Stock, Value, Issued		$ 22
Additional paid in capital			209,213
Accumulated Other Comprehensive Income (Loss), Net of Tax				(12)
Retained Earnings (Accumulated Deficit)					352,811
Treasury Stock, Value						(186,291)
Stockholders' Equity Attributable to Parent							375,743
Stockholders' Equity Attributable to Noncontrolling Interest								1,574
Balance at at Dec. 31, 2013	377,317
Stock-based compensation expense	6,362	$ 0	6,362	0	0	0	6,362	0
Issuance of restricted stock		55,000
Exercises of stock options and stock-settled SARs (Shares)		93,000
Exercises of stock options and stock-settled SARs	2,240	$ 0	2,240	0	0	0	2,240	0
Tax benefit from stock based compensation	3,442	$ 0	3,442	0	0	0	3,442	0
Assets sold in acquisition of ownership interest in subsidiary	$ 0
Cancellation of restricted stock		(11,000)
Stock Repurchased During Period, Shares	(1,268,289)	(1,268,000)
Shares repurchased by the Company and held as treasury shares	$ (139,105)	$ 0	0	0	0	(139,105)	(139,105)	0
Dividends, Cash	(43,717)	0	0	0	(43,717)	0	(43,717)	0
Unrealized gain on short-term investments, net of tax	1,223	0	0	1,223	0	0	1,223	0
Net income (loss)	$ 86,303	$ 0	0	0	86,689	0	86,689	(386)
Common stock, shares issued	17,413,307	17,413,000
Common Stock, Value, Issued	$ 22	$ 22
Additional paid in capital	221,257		221,257
Accumulated Other Comprehensive Income (Loss), Net of Tax	1,211			1,211
Retained Earnings (Accumulated Deficit)	395,783				395,783
Treasury Stock, Value	(325,396)					(325,396)
Stockholders' Equity Attributable to Parent	292,877						292,877
Stockholders' Equity Attributable to Noncontrolling Interest	1,188							1,188
Balance at at Dec. 31, 2014	294,065
Stock-based compensation expense	5,383		5,383				5,383
Issuance of restricted stock		48,000
Exercises of stock options and stock-settled SARs (Shares)		37,000
Exercises of stock options and stock-settled SARs	1,924		1,924				1,924
Tax benefit from stock based compensation	3,865		3,865				3,865
Gain (Loss) on Disposition of Stock in Subsidiary	(702)		(3,484)		3,926		442	(1,144)
Assets sold in acquisition of ownership interest in subsidiary	$ 0
Cancellation of restricted stock		(8,000)
Stock Repurchased During Period, Shares	(694,685)	(695,000)
Shares repurchased by the Company and held as treasury shares	$ (129,455)					(129,455)	(129,455)
Stock Issued During Period, Shares, Employee Stock Purchase Plans	8,306	8,000
Stock Issued During Period, Value, Employee Stock Purchase Plan	$ 1,436					1,436	1,436
Dividends, Cash	(46,464)				(46,464)		(46,464)
Unrealized gain on short-term investments, net of tax	(377)			(377)			(377)
Net income (loss)	$ 220,330				220,374		220,374	(44)
Common stock, shares issued	16,802,897	16,803,000
Common Stock, Value, Issued	$ 22	$ 22
Additional paid in capital	228,945		$ 228,945
Accumulated Other Comprehensive Income (Loss), Net of Tax	834			$ 834
Retained Earnings (Accumulated Deficit)	573,619				$ 573,619
Treasury Stock, Value	(453,415)					$ (453,415)
Stockholders' Equity Attributable to Parent	350,005						$ 350,005
Stockholders' Equity Attributable to Noncontrolling Interest	$ 0							$ 0

Consolidated Statements of Sto8

Consolidated Statements of Stockholders' Equity (Parentheticals) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Stockholders' Equity [Abstract]
Cash dividends (per Share)	$ 2.75	$ 2.50	$ 2.25

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Dividends, Cash	$ 46,464	$ 43,717	$ 41,787
OPERATING ACTIVITIES:
NET INCOME	220,330	86,303	91,779
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	98,097	83,409	69,264
Loss on aircraft and other equipment disposals	4,630	7,100	8,000
Special charge	0	43,280	0
Provision for obsolescence of expendable parts, supplies and fuel	1,604	1,301	827
Amortization of deferred financing costs	1,099	2,215	612
Share-based compensation expense	10,474	16,723	9,818
Deferred income taxes	8,979	(7,353)	(1,945)
Excess tax benefits from share-based compensation	(3,865)	(3,442)	(1,689)
Changes in certain assets and liabilities:
Accounts receivable	(930)	2,641	1,778
Prepaid expenses	6,030	8,591	(8,526)
Accounts payable	(6,431)	851	3,140
Accrued liabilities	13,910	11,309	3,695
Air traffic liability	12,821	17,927	19,474
Other, net	(1,381)	(1,074)	661
Net cash provided by operating activities	365,367	269,781	196,888
INVESTING ACTIVITIES:
Purchase of investment securities	(357,546)	(334,538)	(351,616)
Proceeds from maturities of investment securities	373,816	297,968	325,367
Purchase of property and equipment, including pre-delivery deposits	(252,686)	(279,418)	(177,516)
Change in deposits and other assets	125	506	10,233
Payments for (Proceeds from) Other Investing Activities	2,073	234	700
Net cash used in investing activities	(234,218)	(315,248)	(192,832)
FINANCING ACTIVITIES:
Cash dividends paid to shareholders	(62,439)	(41,787)	0
ExcessTaxBenefitsFromStockBasedCompensationFinancingActivities	3,865	3,442	1,689
Proceeds from the exercise of stock options	1,924	2,240	2,083
Proceeds from the issuance of long-term debt	121,000	385,300	106,000
Repurchase of common stock	(129,455)	(139,105)	(83,607)
Principal payments on long-term debt	(67,930)	(168,794)	(22,656)
Proceeds from (Payments for) Other Financing Activities	(612)	(3,930)	589
Net cash (used in) provided by financing activities	(133,647)	37,366	4,098
Net change in cash and cash equivalents	(2,498)	(8,101)	8,154
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	89,610	97,711	89,557
CASH AND CASH EQUIVALENTS AT END OF PERIOD	87,112	89,610	97,711
Cash payments for:
Interest, net of amount capitalized	23,574	19,270	8,710
Income taxes, net of refunds	111,399	55,501	53,220
Non-cash transactions:
Assets acquired in sale of ownership interest in subsidiary	0	0	530
Assets sold in acquisition of ownership interest in subsidiary	0	0	1,225
Long-term debt assumed for aircraft	0	141,960	0
Parent
Dividends, Cash	46,464	43,717	41,787
OPERATING ACTIVITIES:
NET INCOME	$ 220,374	$ 86,689	$ 92,273

Organization and Business of Co

Organization and Business of Company (Notes)	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Business of Company	Organization and Business of Company Allegiant Travel Company (the “Company”) is a leisure travel company focused on providing travel services and products to residents of under-served cities in the United States. The Company operates a low-cost passenger airline which sells air transportation both on a stand-alone basis and bundled with the sale of air-related and third party services and products. The Company also provides air transportation under fixed fee flying arrangements, and generates aircraft lease revenue. Scheduled service and fixed fee air transportation services have similar operating margins, economic characteristics, production processes (check-in, baggage handling and flight services) which target the same class of customers, and are subject to the same regulatory environment. As a result, the Company believes it operates in one reportable segment and does not separately track expenses for scheduled service and fixed fee air transportation services.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying consolidated financial statements include the accounts of Allegiant Travel Company and its majority-owned operating subsidiaries. The Company's investments in unconsolidated affiliates, which are 50 percent or less owned, are accounted for under the equity method. All intercompany balances and transactions have been eliminated in consolidation. Certain reclassifications, including those related to the adoption of Accounting Standard Update ("ASU") 2015-03, have been made to the prior period financial statements to conform to 2015 classifications. These reclassifications had no effect on previously reported net income. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements based on events and transactions occurring during the periods reported, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates. Cash and Cash Equivalents Cash and cash equivalents include investments and interest bearing instruments with maturities of three months or less at the balance sheet date. Such investments are carried at cost which approximates fair value. Restricted Cash Restricted cash represents escrowed funds under fixed fee contracts, and cash collateral against letters of credit required by hotel properties for guaranteed room availability, airports and certain other parties. Accounts Receivable Accounts receivable are carried at face amount which approximates fair value. They consist primarily of amounts due from credit card companies associated with the sale of tickets for future travel, and amounts due related to fixed fee charter agreements. If deemed necessary, the Company records an allowance for doubtful accounts for amounts not expected to be collected. The Company did not record an allowance for doubtful accounts as of December 31, 2015 or 2014 . Investment Securities The Company’s investments in marketable securities are classified as available-for-sale and are reported at fair market value with the net unrealized gain or (loss) reported as a component of accumulated other comprehensive income in shareholders’ equity. Investment securities are classified as cash equivalents, short-term investments and long-term investments based on maturity date as of the balance sheet date. Cash equivalents have maturities of three months or less, short-term investments have maturities of greater than three months but equal to or less than one year, and long-term investments are those with a maturity date greater than one year. As of December 31, 2015 , the Company’s long-term investments consisted of corporate debt securities, government debt securities and municipal debt securities with contractual maturities of less than 24 months. Investment securities consisted of the following (in thousands): As of December 31, 2015 As of December 31, 2014 Net Unrealized Net Unrealized Cost Gains (Losses) Market Value Cost Gains (Losses) Market Value Money market funds $ 781 $ — $ — $ 781 $ 8,377 $ — $ — $ 8,377 Certificates of deposit — — — — 10,049 2 — 10,051 Commercial paper 83,155 — (1 ) 83,154 47,941 3 (4 ) 47,940 Municipal debt securities 52,669 2 (1 ) 52,670 105,933 14 (2 ) 105,945 US Treasury bond 1,607 — (1 ) 1,606 24,028 — (31 ) 23,997 Corporate debt securities 108,485 50 (154 ) 108,381 134,770 1 (106 ) 134,665 Federal agency debt securities 73,783 — (80 ) 73,703 4,711 — (1 ) 4,710 Total $ 320,480 $ 52 $ (237 ) $ 320,295 $ 335,809 $ 20 $ (144 ) $ 335,685 The amortized cost of investment securities sold is determined by the specific identification method with any realized gains or losses reflected in other (income) expense. The Company had minimal realized losses during the years ended December 31, 2015 , 2014 , and 2013 . The Company believes unrealized losses related to debt securities are not other-than-temporary and does not intend to sell these securities prior to amortized cost recoverability. The Company attempts to minimize its concentration risk with regard to its cash, cash equivalents, and investment portfolio. This is accomplished by diversifying and limiting amounts among different counterparties, the type of investment, and the amount invested in any individual security, commercial paper, or money market fund. Expendable Parts, Supplies and Fuel Expendable parts, supplies and fuel inventories are valued at cost using the first-in, first-out method. Such inventories are charged to expense as they are used in operations. An obsolescence allowance for expendable parts is accrued based on the estimated lives of corresponding fleet type and salvage values. The allowance for expendable inventories was $4.6 million and $3.0 million at December 31, 2015 and 2014 respectively. Fuel inventory was $3.9 million and $5.5 million at December 31, 2015 and 2014 , respectively. Rotable aircraft parts inventories are included in flight equipment. Software Capitalization The Company capitalizes certain internal and external costs related to the acquisition and development of computer software during the application development stage of projects. Costs incurred during the preliminary and post-implementation stages are expensed as incurred. The Company amortizes these capitalized costs using the straight-line method over the estimated useful life of the software, which typically ranges from three to five years. The Company had unamortized computer software development costs of $38.2 million and $31.8 million as of December 31, 2015 and 2014 , respectively. Amortization expense related to computer software was $10.0 million , $6.7 million and $3.3 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. Property and Equipment Property and equipment are recorded at cost and depreciated using the straight-line method over their estimated useful lives less an estimated salvage value. Aircraft and engines have an estimated average residual value of 14.7 percent of original cost as of December 31, 2015 ; other property and equipment are assumed to have no residual value. The depreciable lives used for the principal depreciable asset classifications are: Aircraft and related flight equipment: MD83/88 3-9 years Boeing 757-200 2 years Airbus A320 Series 10-15 years Rotable parts 7 years Buildings 25 years Equipment and leasehold improvements 3-7 years Computer hardware and software 3-5 years In estimating the useful lives and residual values of its aircraft, the Company primarily has relied upon actual experience with the same or similar aircraft types, current and projected future market information, and recommendations from other industry sources. Subsequent revisions to these estimates could be caused by changing market prices of the Company’s aircraft, changes in utilization of the aircraft, and other fleet events. These estimates are evaluated each reporting period and adjusted if necessary. Changes in the estimate for useful lives or residual values of the Company’s property and equipment could result in an acceleration of depreciation expense. Interest attributable to funds used to finance the refurbishment of aircraft prior to revenue service is capitalized as an additional cost of the related asset, provided that the refurbishment is extensive or requires an extended period of time to complete, generally longer than 90 days. Interest is capitalized at the Company’s average interest rate on long-term debt and ceases when the asset is ready for service. Leased Aircraft Return Costs The Company has been party to operating lease agreements which contain aircraft return provisions. These provisions require the Company to compensate the lessor based on specific time remaining on certain aircraft and engine components between scheduled maintenance events. A liability associated with returning leased aircraft is accrued when it is probable that a cash payment will be made and that amount is reasonably estimable. Any accrual is based on the time remaining on the lease, planned aircraft usage and other provisions included in the lease agreement, although the actual amount due to any lessor upon return is not known with certainty until lease termination. Two previously leased Airbus A320 series aircraft were purchased in 2014, at which time the lease return condition accrual of $1.4 million as of December 31, 2013 was reversed. As of December 31, 2015 , the Company has no remaining aircraft under lease agreements. Aircraft Maintenance and Repair Costs The Company accounts for non-major maintenance and repair costs incurred under the direct expense method. Under this method, maintenance and repair costs for owned and leased aircraft, excluding major maintenance activities, are charged to operating expenses as incurred. Maintenance and repair costs includes all parts, materials, line maintenance, and non-major maintenance activities required to maintain the Company's multiple fleet types. The Company accounts for major maintenance costs for MD-80 airframes and the related JT8 engines using the direct expense method. Under this method, major maintenance costs are charged to expense as incurred. This method can result in expense volatility between quarterly and annual periods, depending on the number and type of major maintenance activities performed. Scheduled maintenance activities are the most extensive in scope and are primarily based on time and usage intervals, including, but not limited to, airframe and engine overhauls. The Company has not experienced major maintenance events for its Airbus A320 series or 757-200 fleets and as such, has not yet applied a method to account for major maintenance for these aircraft types. Measurement of Impairment of Long-Lived Assets The Company records impairment losses on long-lived assets used in operations, consisting principally of property and equipment, when events or changes in circumstances indicate, in management’s judgment, that the assets might be impaired, and the undiscounted future cash flows estimated to be generated by those assets are less than the carrying amount of those assets. In making these determinations, the Company utilizes certain assumptions, including, but not limited to: (i) estimated fair market value of the assets; and (ii) estimated future cash flows expected to be generated by these assets, which are based on additional assumptions such as asset utilization, length of service for which the asset will be used in operations, and estimated salvage values. For the years ended December 31, 2015 , 2014 and 2013 , the Company incurred impairment losses on spare engine parts of $1.1 million , $3.4 million and $5.3 million , respectively. In the fourth quarter 2014, the Company recorded a non-cash impairment charge of $43.3 million on its fleet of Boeing 757 aircraft, engines, and related assets as a result of its review of fleet value. The review was based on factors such as the Company's ability or intent to operate fleet types through their estimated useful lives, potential changes to the fleet residual values based on changes in market conditions for used aircraft, spare engines and parts, and potential changes to the scheduled revenue network based on competition trends and operational performance. Refer to Note 8 – Fair Value Measurements for further discussion. Revenue Recognition Scheduled service revenue consists of passenger revenue generated from nonstop flights in the Company’s route network, recognized either when the travel-related service or transportation is provided or when the itinerary expires unused. Nonrefundable scheduled itineraries expire on the date of the intended flight, unless the date is extended by notification from the customer in advance. Itineraries sold for transportation not yet used, as well as unexpired credits, are included in air traffic liability. Various taxes and fees, assessed on the sale of tickets to customers, are collected by the Company serving as an agent, and remitted to taxing authorities. These taxes and fees are presented on a net basis in the Company’s consolidated statements of income and recorded as a liability until remitted to the appropriate taxing authority. Fixed fee contract revenue consists of agreements to provide charter service on a year-round and ad hoc basis. Fixed fee contract revenue is recognized when the transportation is provided. Ancillary air-related revenue is generated from fees paid by ticketed passengers and consists of baggage fees, the use of the Company’s website to purchase scheduled service transportation, advance seat assignments, and other services. Revenues from air-related charges are recognized when the transportation is provided if the product is not deemed independent of the original ticket sale. Change and cancellation fees for nonrefundable itineraries are air-related charges deemed independent of the original ticket sale, and are recognized as revenue when the sale occurs. Ancillary revenue is also generated from the sale of third party products such as hotel rooms, rental cars, ticket attractions, and other items. Revenue from the sale of third party products is recognized at the time the product is utilized, such as the time a purchased hotel room is occupied. The Company follows accounting standards for revenue arrangements with multiple deliverables to determine the amount of revenue to be recognized for each element of a bundled sale involving air-related charges and third party products in addition to airfare. Revenue from the sale of third party products is recorded net of amounts paid to wholesale providers, travel agent commissions, and transaction costs. Other revenue is generated from leased out aircraft and flight equipment, and other miscellaneous sources. Lease revenue is recognized pro-rata over the lease term. Advertising Costs Advertising costs are charged to expense in the period incurred. Advertising expense was $12.7 million , $6.0 million and $4.2 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. Earnings per Share Basic and diluted earnings per share are computed pursuant to the two-class method. Under this method, the Company attributes net income to two classes, common stock and unvested restricted stock awards. Unvested restricted stock awards granted to employees under the Company’s Long-Term Incentive Plan are considered participating securities because they receive non-forfeitable rights to cash dividends at the same rate as common stock. Diluted net income per share is calculated using the more dilutive of two methods. Under both methods, the exercise of employee stock options and stock-settled stock appreciation rights are assumed using the treasury stock method. The assumption of vesting of restricted stock, however, differs as described below: 1. Assume vesting of restricted stock using the treasury stock method. 2. Assume unvested restricted stock awards are not vested, and allocate earnings to common shares and unvested restricted stock awards using the two-class method. For the years ended December 31, 2015 , 2014 and 2013 , the second method above was used in the computation because it was more dilutive than the first method. The following table sets forth the computation of net income per share on a basic and diluted basis for the periods indicated (in thousands, except per share amounts): Year ended December 31, 2015 2014 2013 Basic: Net income attributable to Allegiant Travel Company $ 220,374 $ 86,689 $ 92,273 Less net income allocated to participating securities (961 ) (293 ) (381 ) Net income attributable to common stock $ 219,413 $ 86,396 $ 91,892 Net income per share, basic $ 12.97 $ 4.87 $ 4.85 Weighted-average shares outstanding 16,923 17,729 18,936 Diluted: Net income attributable to Allegiant Travel Company $ 220,374 $ 86,689 $ 92,273 Less net income allocated to participating securities (958 ) (292 ) (378 ) Net income attributable to common stock $ 219,416 $ 86,397 $ 91,895 Net income per share, diluted $ 12.94 $ 4.86 $ 4.82 Weighted-average shares outstanding 16,923 17,729 18,936 Dilutive effect of stock options, restricted stock and stock-settled stock appreciation rights 69 88 154 Adjusted weighted-average shares outstanding under treasury stock method 16,992 17,817 19,090 Participating securities excluded under two-class method (30 ) (35 ) (40 ) Adjusted weighted-average shares outstanding under two-class method 16,962 17,782 19,050 Stock awards outstanding of 28,789 , 75,233 , and 91,028 shares for 2015 , 2014 , and 2013 , respectively, were excluded from the computation of diluted earnings per share as they were antidilutive. Share-Based Compensation The Company accounts for share-based compensation in accordance with accounting standards which require the compensation cost related to share-based payment transactions be recognized in the Company’s consolidated statements of income. The cost is measured at the grant date, based on the calculated fair value of the award using the Black-Scholes option pricing model for stock options and cash-settled SARs, and is remeasured monthly for cash-settled SARs. Cost is based on the closing share price of the Company’s stock on the grant date for restricted stock awards. The cost is recognized as an expense over the employee’s requisite service period, the vesting period of the award, which is generally three years. The Company’s share-based employee compensation plan is more fully discussed in Note 12—Employee Benefit Plans. Income Taxes The Company recognizes deferred income taxes based on the asset and liability method required by accounting standards. Deferred tax assets and liabilities are determined based on the timing differences between book basis for financial reporting purposes and tax basis of the asset and liability and measured using the enacted tax rates. A valuation allowance for deferred tax assets is provided if it is more likely than not that some portion or all of the deferred tax assets will not be realized. The Company determines the net non-current deferred tax assets or liabilities separately for federal, state, foreign and other local jurisdictions. The Company’s income tax returns are subject to examination by the Internal Revenue Service (“IRS”) and other tax authorities in the jurisdictions where the Company operates. The Company assesses potentially unfavorable outcomes of such examinations based on the criteria set forth in uncertain tax position accounting standards. The accounting standards prescribe a minimum recognition threshold a tax position is required to meet before being recognized in the financial statements. Accounting standards for income taxes utilize a two-step approach for evaluating tax positions. Recognition (Step I) occurs when the Company concludes that a tax position, based on its technical merits, is more likely than not to be sustained upon examination. Measurement (Step II) is only addressed if the position is deemed to be more likely than not to be sustained. Under Step II, the tax benefit is measured as the largest amount of benefit that is greater than 50 percent likely of being realized upon settlement. The tax positions failing to qualify for initial recognition are recognized in the first subsequent interim period they meet the “more likely than not” standard. If it is subsequently determined that a previously recognized tax position no longer meets the “more likely than not” standard, it is required that the tax position be derecognized. As applicable, the Company will recognize accrued penalties and interest related to unrecognized tax benefits in the provision for income taxes. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU 2014-09, intended to create a unified model to determine when and how revenue is recognized. The core principle is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In July 2015, the FASB deferred the effective date by one year, to December 15, 2017, for annual and interim periods beginning after that date. Early adoption is also permitted but not before the original effective date of annual periods beginning after December 15, 2016. The Company is evaluating the impact on its financial statements of adopting this new accounting standard and plans to provide additional information regarding its expected financial impact at a later date. In April 2015, the FASB issued ASU 2015-03, which amends existing guidance and requires the presentation of debt issuance costs on the balance sheet as a reduction of the carrying amount of the related debt liability rather than as a deferred charge, effective for fiscal years, and interim periods within those years beginning on or after December 15, 2015 and early adoption is permitted. The Company retrospectively adopted this standard as of December 31, 2015. Debt issuance costs previously reflected on the balance sheet in deposits and other assets, are now reflected as a reduction to long-term debt, in the amount of $4.5 million and $4.3 million as of December 31, 2015 and December 31, 2014, respectively. In November 2015, the FASB issued ASU 2015-17, requiring all deferred tax assets and liabilities, and any related valuation allowance, to be classified as non-current on the balance sheet, effective for fiscal years, and interim periods within those years, beginning on or after December 15, 2016 and early adoption is permitted. The purpose of the classification change is to simplify the presentation of deferred income taxes on the Consolidated Balance Sheet. The Company has elected to prospectively adopt this accounting principle as of December 31, 2015. Prior periods in the consolidated financial statements have not been retrospectively adjusted.

Property and Equipment (Notes)

Property and Equipment (Notes)	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment Disclosure	Property and Equipment Property and equipment consisted of the following (in thousands): As of December 31, 2015 As of December 31, 2014 Flight equipment $ 1,123,115 $ 947,082 Computer hardware and software 78,200 58,173 Ground property and equipment 72,078 42,743 Total property and equipment 1,273,393 1,047,998 Less accumulated depreciation and amortization (387,451 ) (309,215 ) Property and equipment, net $ 885,942 $ 738,783 The following table summarizes the Company's total in-service aircraft fleet as of December 31, 2015 : Aircraft Type Owned (1) Seating Capacity Average Age MD-83/88 51 166 26.0 Boeing 757-200 5 215 22.8 Airbus A319 (2) 10 156 11.0 Airbus A320 (3) 14 177 15.9 Total aircraft 80 (1) Refer to Note 5 – Long-Term Debt for discussion of the Company's notes payable secured by aircraft. (2) Does not include 12 Airbus A319 aircraft currently on lease to a European carrier until 2018 or one Airbus 319 aircraft being prepared for revenue service. (3) Does not include two Airbus A320 aircraft being prepared for revenue service.

Accrued Liabilities (Notes)

Accrued Liabilities (Notes)	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Accounts Payable and Accrued Liabilities Disclosure	Accrued Liabilities Accrued liabilities consisted of the following (in thousands): As of December 31, 2015 As of December 31, 2014 Salaries, wages and benefits $ 37,545 $ 30,949 Dividends 27,728 43,703 Station expenses 11,668 7,683 Maintenance and repairs 7,287 4,727 Passenger fees 9,007 8,219 Passenger taxes 1,415 705 Interest 7,900 8,875 Other accruals 6,912 5,941 Total accrued liabilities $ 109,462 $ 110,802 As of December 31, 2015 , the increase in salaries, wages and benefits payable was mostly due to an increase to the bonus accrual as the Company achieved higher profits in 2015 compared to 2014 . Dividends payable decreased year over year as the Company declared a $1.65 per share dividend in December 2015 compared to $2.50 per share in 2014 , in each case, paid in January of the following year.

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt Long-term debt consisted of the following (in thousands): As of December 31, 2015 As of December 31, 2014 Fixed-rate notes payable due through 2020 $ 341,738 $ 343,625 Variable-rate notes payable due through 2020 299,940 245,169 Total long-term debt, net of related costs 641,678 588,794 Less current maturities 74,069 52,605 Long-term debt, net of current maturities and related costs $ 567,609 $ 536,189 Maturities of long-term debt, as of December 31, 2015, for the next five years and thereafter, in the aggregate, are: 2016 - $74.1 million ; 2017 - $76.4 million ; 2018 - $133.1 million ; 2019 - $336.9 million ; 2020 - $21.2 million ; and none thereafter. Secured Debt In December 2015, the Company borrowed $28.0 million secured by two A319 aircraft. The notes bear interest at a floating rate based on LIBOR plus 1.70 percent and are payable in quarterly installments through December 2020. In September 2015, the Company borrowed $29.0 million secured by two A319 aircraft. The notes bear interest at a floating rate based on LIBOR plus 1.75 percent and are payable in quarterly installments through September 2020. In June 2015, the Company borrowed $26.5 million secured by two A319 aircraft. The notes bear interest at a floating rate based on LIBOR plus 1.70 percent and are payable in quarterly installments through June 2020. In March 2015, the Company borrowed $30.0 million secured by two A319 aircraft. The notes bear interest at a floating rate based on LIBOR plus 1.70 percent , and are payable in quarterly installments through March 2020. In March 2015, the Company borrowed $7.5 million secured by the real estate purchased by the Company in October 2014. The note bears a fixed interest rate of 2.86 percent per annum, and provides for a 25-year amortization and a five-year term. In June 2014, the Company assumed $142.0 million of debt in connection with the acquisition of 12 separate special purpose companies, each owning one Airbus A319 aircraft. The notes payable assumed bear interest based on LIBOR plus 3.08 percent and are payable in monthly installments through November 2018, at which time a balloon payment is due. In May 2014, the Company borrowed $40.0 million secured by all six of the Company's Boeing 757-200 aircraft. The notes bear interest at LIBOR plus 2.95 percent and are payable in monthly installments through May 2018, at which time a balloon payment is due. In October 2015, in connection with its retirement, the Company prepaid $4.6 million due on the note payable for one Boeing 757-200 aircraft. In April 2014, the Company borrowed $45.3 million under a loan agreement secured by all of the Company's MD-80 aircraft. The note payable issued under the loan agreement bears interest at LIBOR plus 2.95 percent and is payable in monthly installments through April 2018, at which time a balloon payment is due. Concurrently, the Company prepaid the remaining $121.1 million balance of its senior secured term loan facility (the "Term Loan"). The original maturity date of the Term Loan was March 2017 and it bore interest based on LIBOR with a LIBOR floor of 1.50 percent . In the second quarter 2014, the Company prepaid, in full, the $8.5 million balance owed on its note payable secured by two Boeing 757-200 aircraft originally due in July 2016. Senior Secured Revolving Credit Facility In December 2015, the Company, through a wholly owned subsidiary, entered into a senior secured revolving credit facility under which it will be able to borrow up to $56.0 million . The amount that may be drawn under the facility and the outstanding debt balance are based on the value of Airbus A320 series aircraft which the Company may choose to place in the collateral pool. The facility has a term of 24 months and may be extended for two further one-year periods at the lender’s option. Any notes under the facility will bear interest at a floating rate based on LIBOR plus 1.85 percent . An individual aircraft may remain in the collateral pool for up to one year. As of December 31, 2015, no amount had been borrowed against this credit facility. General Unsecured Senior Notes In June 2014, the Company completed an offering of $300.0 million aggregate principal amount of senior unsecured obligations (the "Notes") which will mature in July 2019. The Notes constitute general unsecured senior obligations of the Company and rank equally in right of payment with all existing and future senior unsecured indebtedness and liabilities (including trade payables) of the Company. The Notes are effectively junior to the Company’s existing and future secured indebtedness. The Notes are guaranteed by all of the Company’s wholly-owned domestic subsidiaries and rank equally in right of payment with all existing and future unsecured indebtedness and liabilities (including trade payables) of the Company’s guarantor subsidiaries, but effectively junior to the guarantors’ existing and future secured indebtedness. The Notes bear interest at a rate of 5.5 percent per year, payable in cash semi-annually, on January 15 and July 15 of each year, and will mature on July 15, 2019. At any time, the Company may redeem the Notes, in whole or in part, at a price equal to 100 percent of the principal amount of the Notes, plus accrued and unpaid interest, plus a “make-whole premium.” The occurrence of specific kinds of changes in control will be a triggering event requiring the Company to offer to purchase, from holders, all or a portion of the Notes at a price equal to 101 percent of the principal amount, together with accrued and unpaid interest to the date of purchase. The indenture pursuant to which the Notes were issued includes operating and financial restrictions on the Company. These restrictions limit or restrict, among other things, the Company’s ability and the ability of its restricted subsidiaries to (i) incur additional indebtedness; (ii) incur liens; (iii) make restricted payments (including paying dividends on, redeeming, repurchasing or retiring capital stock); (iv) make investments; and (v) consolidate, merge or sell all or substantially all of its assets. These covenants are subject to various exceptions and qualifications under the terms of the indenture. As of December 31, 2015, management believes the Company is in compliance with all covenants under the indenture.

Leases (Notes)

Leases (Notes)	12 Months Ended
	Dec. 31, 2015
Leases [Abstract]
Leases	Leases The Company has leased aircraft, engines and other assets, including office facilities, airport and terminal facilities, and office equipment for which the majority have terms extending through 2020. Total rental expense for operating leases for the years ended December 31, 2015 , 2014 and 2013 was $7.9 million , $8.8 million and $13.1 million , respectively. Included in total rental expense is $1.0 million and $5.5 million in 2014 and 2013, respectively, of aircraft lease rentals expense for two Airbus A320 series aircraft which were purchased in 2014; no such expense was incurred in 2015. Additionally, aircraft sub-service expense was $2.1 million , $14.8 million , and $4.2 million in 2015, 2014 and 2013, respectively. Aircraft leases In August 2014, the Company entered into an agreement with the lessor of eight Airbus A320 series aircraft to terminate its existing operating leases ( two aircraft had been delivered) and simultaneously entered into a purchase agreement with the lessor for the purchase of the same aircraft. The Company performed a valuation of this acquisition and, concluding that the purchase price was stated at fair value, recognized no associated impairment or lease termination costs. Airport and other facilities leases Office facilities under lease include approximately 10,000 and 87,000 square feet of space used for corporate and training purposes, with expiration dates ranging between 2018 and 2020. The Company is responsible for its share of common area maintenance charges under both leases. An additional 70,000 square feet of corporate office space was under lease through May 2015. Airport and terminal facility leases are entered into with a number of local governments and other third parties. These lease arrangements have a variety of terms and conditions. Scheduled future minimum lease payments At December 31, 2015 , scheduled future minimum lease payments under operating leases with initial or remaining non-cancelable lease terms in excess of one year are: 2016 - $5.1 million ; 2017 - $3.6 million ; 2018 - $2.3 million ; 2019 - $1.7 million ; 2020 - $1.3 million ; and thereafter - $3.3 million . In addition, scheduled future minimum airport fee payments under airport use and lease agreements with fixed and remaining non-cancelable terms in excess of one year are: 2016 - $11.0 million ; 2017 - $5.9 million ; and thereafter - $0.8 million .

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Stockholders' Equity	Shareholders’ Equity The Company is authorized by its Board of Directors to acquire the Company’s stock through open market and private purchases under its share repurchase program. As repurchase authority is used, the Board of Directors has, to date, authorized additional expenditures for share repurchases. Share repurchases consisted of the following during the periods indicated: Twelve Months Ended December 31, 2015 2014 2013 Shares repurchased 694,685 1,268,289 927,006 Average price per share $ 186.35 $ 109.68 $ 90.03 Total (in thousands) $ 129,455 $ 139,105 $ 83,462 As of December 31, 2015 , the Company had $54.1 million in unused share repurchase authority remaining under the Board approved program. During 2015, the Board declared quarterly cash dividends of $1.10 per share for a total of $18.7 million paid by the Company during the year. Prior to year-end, the Board declared a special cash dividend of $1.65 per share on outstanding common stock payable to shareholders of record on December 18, 2015. On January 8, 2016, the Company paid $27.7 million to these shareholders. On December 3, 2014, the Board declared a special cash dividend of $2.50 per share on its outstanding common stock payable to shareholders of record on December 19, 2014. On January 6, 2015, the Company paid $43.7 million to these shareholders. On November 14, 2013, the Board declared a special cash dividend of $2.25 per share on its outstanding common stock payable to shareholders of record on December 13, 2013. On January 3, 2014, the Company paid $41.8 million to these shareholders.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Investments The Company measures certain financial assets and liabilities at fair value on a recurring basis. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. Accounting standards pertaining to fair value measurements establish a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: Level 1 - Defined as observable inputs such as quoted prices in active markets for identical assets or liabilities Level 2 - Defined as inputs other than Level 1 inputs that are either directly or indirectly observable Level 3 - Defined as unobservable inputs for which little or no market data exists, therefore requiring an entity to develop its own assumptions The Company uses the market approach valuation technique to determine fair value for investment securities. The assets classified as Level 1 consist of money market funds for which original cost approximates fair value. The assets classified as Level 2 consist of certificates of deposit, commercial paper, municipal debt securities, federal agency debt securities, government debt securities, corporate debt securities, and US treasury bonds, which are valued using quoted market prices or alternative pricing sources including transactions involving identical or comparable assets and models utilizing market observable inputs. The Company has no investment securities classified as Level 3. For those assets classified as Level 2 that are not in active markets, the Company obtains fair value from pricing sources using quoted market prices for identical or comparable instruments, and uses pricing models which include all significant observable inputs: maturity dates, issue dates, settlement dates, benchmark yields, reported trades, broker-dealer quotes, issue spreads, benchmark securities, bids, offers and other market related data. These inputs are observable or can be derived from, or corroborated by, observable market data for substantially the full term of the asset. The fair value of the Company's derivative instrument is determined using standard valuation models. The significant inputs used in these models are readily available in public markets or can be derived from observable market transactions and therefore have been classified as Level 2. Inputs used in these standard valuation models for derivative instruments include the applicable exchange and interest rates. Financial instruments measured at fair value on a recurring basis (in thousands): Description As of Level 1 Level 2 Cash equivalents Commercial paper $ 8,426 $ — $ 8,426 Money market funds 781 781 — Municipal debt securities 754 — 754 Total cash equivalents 9,961 781 9,180 Short-term Corporate debt securities 80,957 — 80,957 Municipal debt securities 47,073 — 47,073 Commercial paper 74,728 — 74,728 Federal agency debt securities 42,825 — 42,825 Total short-term 245,583 — 245,583 Long-term Federal agency debt securities 30,878 — 30,878 Corporate debt securities 27,425 — 27,425 Municipal debt securities 4,843 — 4,843 Derivative instruments 2,480 — 2,480 US Treasury Bond 1,606 — 1,606 Total long-term 67,232 — 67,232 Total financial instruments $ 322,776 $ 781 $ 321,995 Description As of Level 1 Level 2 Cash equivalents Money market funds $ 8,377 $ 8,377 $ — Municipal debt securities 101 — 101 Total cash equivalents 8,478 8,377 101 Short-term Corporate debt securities 103,961 — 103,961 Municipal debt securities 103,155 — 103,155 Commercial paper 47,940 — 47,940 Certificates of deposit 10,051 — 10,051 Federal agency debt securities 4,710 — 4,710 Total short-term 269,817 — 269,817 Long-term Corporate debt securities 30,704 — 30,704 Government debt securities 23,997 — 23,997 Municipal debt securities 2,689 — 2,689 Derivative instruments 1,858 — 1,858 Total long-term 59,248 — 59,248 Total financial instruments $ 337,543 $ 8,377 $ 329,166 There were no significant transfers between Level 1 and Level 2 assets for the years ended December 31, 2015 or 2014 . Long-term Debt The fair value of the Company’s publicly held long-term debt is determined based on inputs that are readily available in public markets or can be derived from information available in publicly quoted markets; therefore, the Company has categorized its publicly held debt as Level 2. The remaining debt agreements are not publicly held. The Company has determined the estimated fair value of these notes to be Level 3, as certain inputs used to determine the fair value of these agreements are unobservable and, therefore, could be sensitive to changes in inputs. The Company utilizes the discounted cash flow method to estimate the fair value of Level 3 debt. Carrying value and estimated fair value of long-term debt, including current maturities (in thousands): As of December 31, 2015 As of December 31, 2014 Carrying value Estimated fair value Carrying value Estimated Fair Value Level Publicly held debt $ 300,000 $ 299,250 $ 300,000 $ 304,875 2 Non-publicly held debt 346,179 327,321 293,099 270,490 3 Total long-term debt $ 646,179 $ 626,571 $ 593,099 $ 575,365 Aircraft In the fourth quarter 2014, the Company recorded a non-cash impairment charge of $43.3 million on its fleet of Boeing 757 aircraft, engines, and related assets as a result of a review of fleet value. The Company concluded that the carrying value of these aircraft and related assets was no longer fully recoverable when compared to the estimated remaining future undiscounted cash flows from these assets. Therefore, an adjustment to their fair value with inputs classified as Level 3 was recorded. Other Due to the short term nature, carrying amounts of cash, cash equivalents, restricted cash, accounts receivable and accounts payable approximate fair value.

Derivative Instruments (Notes)

Derivative Instruments (Notes)	12 Months Ended
	Dec. 31, 2015
Derivative Instruments Disclosure [Abstract]
Derivative Instruments and Hedging Activities Disclosure	Derivative Instruments In 2014, the Company entered into a foreign currency swap in order to mitigate the foreign currency exchange rate risk associated with the forecasted lease revenue from 12 Airbus A320 series aircraft leased to a European carrier until 2018. The Company uses a cash flow hedge to minimize the variability in cash flows of assets or liabilities or forecasted transactions caused by fluctuations in foreign currency exchange rates. At December 31, 2015 and 2014 respectively, the change in fair value recorded in accumulated other comprehensive income related to the net unrealized gain on the hedge was $0.9 million and $1.2 million . At inception, the Company formally designated and documented this financial instrument as a hedge of a specific underlying exposure, the risk management objective, and the strategy for undertaking the hedge transaction. The Company also assessed whether the financial instrument used in the hedging transactions was effective at offsetting changes in either the fair values or cash flows of the related underlying exposures. This assessment is monitored on at least a quarterly basis, and the change in fair market value of any ineffective portion of a financial instrument would be immediately recognized into earnings. In 2015, the Company realized $1.3 million in net gains from its cash flow hedge in Other revenue from amounts settled under the forward contract. As of December 31, 2015 it is expected that $0.7 million will be reclassified from Other comprehensive income into Other revenue within the next 12 months. The Company did not realize net gains into Other revenue in 2014. At December 31, 2015 and 2014 respectively, the fair value of the Company's derivative instrument was $2.5 million and $1.9 million and is reported in the Company's consolidated balance sheet within Deposits and other assets. Refer to Note 8 - Fair Value Measurements for additional information related to the estimated fair value.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company is subject to income taxation in the United States, foreign countries and various state jurisdictions in which it operates. In accordance with income tax reporting accounting standards, the Company recognizes tax benefits or expense on the temporary differences between the financial reporting and tax bases of its assets and liabilities. Components of Income/(Loss) Before Income Taxes from Continuing Operations The components of income before taxes for domestic and foreign operations consisted of the following (in thousands): Twelve Months Ended December 31, 2015 2014 2013 Domestic $ 331,813 $ 129,553 $ 146,680 Foreign 14,906 7,578 — Total $ 346,719 $ 137,131 $ 146,680 Income Tax Provision/(Benefit) The provision for income taxes is composed of the following (in thousands): Year Ended December 31, 2015 2014 2013 Current: Federal $ 108,119 $ 53,156 $ 52,732 State 6,501 4,645 4,114 Foreign 996 854 — Total current 115,616 58,655 56,846 Deferred: Federal 9,458 (8,557 ) (1,811 ) State 125 (247 ) (134 ) Foreign 1,190 977 — Total deferred 10,773 (7,827 ) (1,945 ) Total income tax provision $ 126,389 $ 50,828 $ 54,901 Reconciliation of Effective Tax Rate The effective tax rate on income before income taxes differed from the federal statutory income tax rate as follows (in thousands): Year Ended December 31, 2015 2014 2013 Income tax expense at federal statutory rate $ 120,847 $ 48,007 $ 51,362 State income taxes, net of federal income tax benefit 4,293 2,587 2,654 Other 1,249 234 885 Total income tax expense $ 126,389 $ 50,828 $ 54,901 Deferred Taxes The major components of the Company’s net deferred tax assets and liabilities are as follows (in thousands): As of December 31, 2015 2014 Deferred tax assets: Accrued vacation $ 1,339 $ 1,149 Accrued bonus 8,189 4,633 State taxes 2,396 1,484 Accrued property taxes 1,149 1,329 Other 6,940 2,619 Stock-based compensation expense 2,923 2,936 Federal net operating loss — 1,063 Less: valuation allowance — (1,330 ) Total deferred tax assets 22,936 13,883 Deferred tax liabilities: Prepaid expenses 5,314 5,482 Depreciation 60,979 44,116 Foreign deferred 2,223 909 Total deferred tax liabilities 68,516 50,507 Net deferred tax liabilities $ 45,580 $ 36,624 Tax Credit Carryforwards The Company recognized a federal net operating loss ("NOL") carryforward of $0 , $3.1 million and $1.9 million for the years ended December 31, 2015, 2014 and 2013, respectively. As of December 31, 2015, a subsidiary of the Company which previously recognized the NOL was liquidated. In addition, the Company recognized a foreign tax credit carryforward of $0 and $0.3 million for the years ended December 31, 2015 and 2014, respectively, as well as a federal capital loss carryforward of $1.3 million which begins to expire in 2021.

Related Party Transactions (Not

Related Party Transactions (Notes)	12 Months Ended
	Dec. 31, 2015
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Company previously entered into lease agreements for approximately 70,000 and 10,000 square feet of office space in buildings in which the Company’s Chairman and CEO, and an additional member of its Board of Directors, own minority interests as limited partners. Under the terms of these agreements, the Company made rent payments of $1.2 million and $3.1 million in 2015 and 2014 , respectively. The Company exercised its option to terminate the lease for 70,000 square feet of office space effective in May 2015. In connection with the termination of this lease, the Company accrued $1.3 million for unamortized expenses which were subsequently paid, in settlement of litigation, in January 2016. Additionally, as of January 2016, payments for the remaining 10,000 square feet of space will no longer be made to a related party entity as the lender has taken ownership of the property. Game Plane, LLC, a wholly owned subsidiary of the Company, partnered with Alpine Labs, LLC to produce and distribute game shows filmed on Company flights. The Company’s Chairman and CEO owns a 25 percent interest in, and is on the managing board of, Alpine Labs, LLC. The Company made payments of $0.4 million and $2.8 million in 2015 and 2014, respectively, to Alpine Labs, LLC. No additional shows are being filmed and the Company does not expect any further expenses related to this project. During 2015 and 2014 respectively, the Company made payments totaling $2.9 million and $0.8 million to entities owned or controlled by the Company's Chairman and CEO for the building of corporate training content, with a current focus on the Company's operating groups. This approach to training focuses on concept mastery, recognizing that individuals learn at varying paces, through different styles, and is designed to ensure the trainee fully understands each module before moving on to more advanced training. The Company also expects program development to facilitate recurrent training and to contribute to cost savings in the future, and is in the process of seeking approval from the Federal Aviation Administration on various aspects of this training program. In October 2015, the Company's Board of Directors approved an additional commitment of $3.5 million for this project, which is expected to conclude in 2016. GMS Racing LLC competes in the NASCAR Camping World Truck Series and ARCA Racing Series. The Company's Chairman and CEO owns a controlling interest in GMS Racing LLC. During 2015, the Company made sponsorship payments totaling $2.5 million , and none in 2014. No future payments are anticipated. In September 2014, as part of its stock repurchase plan, the Company repurchased all of its former Chief Operating Officer's unvested shares of restricted stock ( 23,623 shares at $124.05 ) and all of his unexercised stock options (options to purchase 127,512 shares at exercise prices between $36.97 per share and $108.59 per share) for a total payment of $8.5 million . Also in September 2014, the Company repurchased 200,000 shares of its common stock from its Chairman and CEO at $126.20 per share, for a total purchase price of $25.2 million . The repurchase prices of the common stock listed above were based on the average closing market price of the Company's stock over the five trading days prior to each sale date.

Employee Benefit Plans (Notes)

Employee Benefit Plans (Notes)	12 Months Ended
	Dec. 31, 2015
Employee Benefit Plans [Abstract]
Employee Benefit Plans	Employee Benefit Plans 401(k) Plan The Company has a defined contribution plan covering all eligible employees. Under the plan, employees may contribute up to 90 percent of their eligible annual compensation with the Company making matching contributions on employee deferrals of up to 5 percent of eligible employee wages. The Company recognized expense under this plan of $4.2 million , $3.4 million and $2.9 million for the years ended December 31, 2015 , 2014 and 2013 , respectively. Share-based employee compensation In 2006, the Board of Directors adopted, and the shareholders approved, a Long-Term Incentive Plan (the “2006 Plan”) and reserved 3,000,000 shares of common stock for the Company to grant stock options, restricted stock, SARs and other stock-based awards to certain officers, directors and employees of the Company. The 2006 Plan is administered by the Company’s compensation committee of the Board of Directors. Employee Stock Purchase Plan In 2014, the Company adopted the 2014 Employee Stock Purchase Plan ("ESPP") and reserved 1,000,000 shares of common stock for employee purchases under the plan. Shares are purchased semi-annually, at a 10 percent discount, based on the market value at period-end. Employees may contribute up to 25 percent of their base pay per offering period, not to exceed $25,000 each calendar year, for the purchase of common stock. The ESPP is a compensatory plan under accounting guidance and results in the recognition of compensation expense. Employees purchased 8,306 shares in 2015 under the ESPP. Compensation expense For the years ended December 31, 2015 , 2014 and 2013 , the Company recorded compensation expense of $10.5 million , $16.7 million and $9.8 million respectively, related to stock options, restricted stock, and cash-settled SARs. The unrecognized compensation cost, and weighted-average period over which the cost is expected to be recognized for non-vested awards as of December 31, 2015 , are presented below: Unrecognized Compensation Cost (thousands) Weighted Average Period (years) Restricted stock $ 6,760 1.69 Cash-settled SARs 3,685 1.38 Stock options 340 1.13 Total $ 10,785 1.57 Fair value The closing price of the Company's stock on the date of grant is used as the fair value for the issuances of restricted stock. The fair value of stock options granted is estimated as of the grant date using the Black-Scholes option pricing model. Cash-settled SARs are liability-based awards for which the fair value and compensation expense recognized are updated monthly, also using the Black-Scholes option pricing model. The following range of assumptions in the Black-Scholes option pricing model was used to determine fair value at the years ended below: 2015 2014 2013 Weighted-average volatility 30.2 % 29.3 % 30.5 % Expected term (in years) 0.3 - 2.5 1.4 - 2.5 0.3 - 2.5 Risk-free interest rate 0.3% - 1.2% 0.4% - 0.9% 0.3% - 0.5% Dividend yield 0.49% - 2.22% 1.80 % — Expected volatilities used for award valuation in 2015, 2014 and 2013 are based on the historical volatility of the Company's common stock price. Expected term represents the weighted average time between the award’s grant date and its exercise date. The Company estimated the expected term assumption in 2015, 2014 and 2013 using historical award exercise activity and employee termination activity. The risk-free interest rate for periods equal to the expected term of an award is based on a blended historical rate using Federal Reserve rates for U.S. Treasury securities. The dividend yield reflects the effect that paying a dividend has on the fair value of the Company's stock. The contractual terms of the Company’s stock option and cash-settled SARs awards granted range from five to ten years. Stock options A summary of option activity as of December 31, 2015 , 2014 and 2013, and changes during the years then ended, is presented below: Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (years) Aggregate Intrinsic Value (thousands) Outstanding at December 31, 2012 228,690 $ 36.89 Granted 108,041 81.77 Exercised (53,100 ) 38.03 Outstanding at December 31, 2013 283,631 49.48 3.38 $ 14,507 Granted 50,630 108.59 Exercised (1) (237,912 ) 38.39 Forfeited (7,600 ) 20.42 Outstanding at December 31, 2014 88,749 69.43 3.29 $ 7,180 Exercised (36,968 ) 52.06 Forfeited (3,000 ) 3.50 Outstanding at December 31, 2015 48,781 $ 86.65 2.62 $ 3,960 Fully vested and expected to vest at December 31, 2015 39,710 $ 81.71 2.50 $ 3,245 Exercisable at December 31, 2015 19,250 $ 58.11 1.98 $ 1,119 (1) Includes 127,512 options purchased from the Company's former Chief Operating Officer in connection with his separation agreement in 2014. Refer to Note 11 - Related Party Transactions for further discussion. During the years ended December 31, 2015 , 2014 and 2013 , the total intrinsic value of options exercised was $5.8 million , $9.4 million and $3.3 million , respectively. Cash received from option exercises for the years ended December 31, 2015 , 2014 and 2013 was $1.9 million , $2.2 million and $2.1 million , respectively. Restricted stock awards A summary of the status of the Company’s non-vested restricted stock grants during the years ended December 31, 2015 , 2014 and 2013 is presented below: Shares Weighted Average Grant Date Fair Value Non-vested at December 31, 2012 128,029 $ 52.63 Granted 85,196 84.36 Vested (64,426 ) 52.57 Forfeited (3,567 ) 82.87 Non-vested at December 31, 2013 145,232 62.61 Granted 54,731 109.66 Vested (1) (90,567 ) 75.31 Forfeited (10,614 ) 79.36 Non-vested at December 31, 2014 98,782 91.15 Granted 47,810 178.68 Vested (54,825 ) 83.35 Forfeited (8,810 ) 130.35 Non-vested at December 31, 2015 82,957 $ 155.30 (1) Includes 23,623 shares of previously unvested restricted stock purchased from the Company's former Chief Operating Officer in connection with his separation agreement in 2014. Refer to Note 11 - Related Party Transactions for further discussion. The total fair value of restricted stock that vested during the years ended December 31, 2015 , 2014 and 2013 was $4.6 million , $6.8 million and $3.4 million , respectively. Cash-settled SARs A summary of cash-settled SARs awards activity during the year ended December 31, 2015 is presented below: Cash-Settled SARs Weighted Average Grant Date Fair Value 3/25/11 Grant Outstanding at January 1, 2015 23,893 $ 19.01 Exercised (10,108 ) 19.01 Forfeited — — Outstanding at December 31, 2015 13,785 $ 19.01 Exercisable at December 31, 2015 13,785 $ 19.01 3/8/13 Grant Outstanding at January 1, 2015 46,545 $ 20.92 Exercised (24,283 ) 20.92 Forfeited (4,554 ) 20.92 Outstanding at December 31, 2015 17,708 $ 20.92 Exercisable at December 31, 2015 3,035 $ 20.92 3/6/14 Grant Outstanding at January 1, 2015 49,075 $ 25.68 Exercised (9,055 ) 25.68 Forfeited (7,790 ) 25.68 Outstanding at December 31, 2015 32,230 $ 25.68 Exercisable at December 31, 2015 7,302 25.68 2/25/15 Grant Outstanding at January 1, 2015 — $ — Granted 77,396 34.53 Forfeited (9,378 ) 34.53 Outstanding at December 31, 2015 68,018 $ 34.53 Exercisable at December 31, 2015 — — As of December 31, 2015 , the accrued liability related to these awards was $4.9 million .

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company is subject to certain legal and administrative actions it considers routine to its business activities. The Company believes the ultimate outcome of any pending legal or administrative matters will not have a material adverse impact on its financial position, liquidity or results of operations. During 2015, the Company entered into purchase agreements for eight Airbus A320 series aircraft yet to be purchased as of December 31, 2015. The remaining obligation of the Company under these agreements as of December 31, 2015 was approximately $129.1 million , to be paid between 2016 and 2017. During 2014, the Company entered into purchase agreements for nine Airbus A320 series aircraft yet to be purchased at the end of that year. Six of these aircraft were acquired in 2015 and the remaining three are scheduled to be acquired in 2016, for which the remaining obligation is approximately $39.4 million .

Subsequent Events (Notes)

Subsequent Events (Notes)	12 Months Ended
	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events In January 2016, the Company received funding for notes secured by two A319 aircraft for $28.0 million , executed in December, 2015. The notes bear interest at a floating rate based on LIBOR plus 1.75 percent and are payable in quarterly installments through January 2021.

Summary of Significant Accoun24

Summary of Significant Accounting Policies - (Policies)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Basis of Presentation [Policy Text Block]	Basis of Presentation The accompanying consolidated financial statements include the accounts of Allegiant Travel Company and its majority-owned operating subsidiaries. The Company's investments in unconsolidated affiliates, which are 50 percent or less owned, are accounted for under the equity method. All intercompany balances and transactions have been eliminated in consolidation. Certain reclassifications, including those related to the adoption of Accounting Standard Update ("ASU") 2015-03, have been made to the prior period financial statements to conform to 2015 classifications. These reclassifications had no effect on previously reported net income.
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements based on events and transactions occurring during the periods reported, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents Cash and cash equivalents include investments and interest bearing instruments with maturities of three months or less at the balance sheet date. Such investments are carried at cost which approximates fair value.
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]	Restricted Cash Restricted cash represents escrowed funds under fixed fee contracts, and cash collateral against letters of credit required by hotel properties for guaranteed room availability, airports and certain other parties.
Receivables, Policy [Policy Text Block]	Accounts Receivable Accounts receivable are carried at face amount which approximates fair value. They consist primarily of amounts due from credit card companies associated with the sale of tickets for future travel, and amounts due related to fixed fee charter agreements. If deemed necessary, the Company records an allowance for doubtful accounts for amounts not expected to be collected. The Company did not record an allowance for doubtful accounts as of December 31, 2015 or 2014 .
Marketable Securities, Policy [Policy Text Block]	Investment Securities The Company’s investments in marketable securities are classified as available-for-sale and are reported at fair market value with the net unrealized gain or (loss) reported as a component of accumulated other comprehensive income in shareholders’ equity. Investment securities are classified as cash equivalents, short-term investments and long-term investments based on maturity date as of the balance sheet date. Cash equivalents have maturities of three months or less, short-term investments have maturities of greater than three months but equal to or less than one year, and long-term investments are those with a maturity date greater than one year. As of December 31, 2015 , the Company’s long-term investments consisted of corporate debt securities, government debt securities and municipal debt securities with contractual maturities of less than 24 months. Investment securities consisted of the following (in thousands): As of December 31, 2015 As of December 31, 2014 Net Unrealized Net Unrealized Cost Gains (Losses) Market Value Cost Gains (Losses) Market Value Money market funds $ 781 $ — $ — $ 781 $ 8,377 $ — $ — $ 8,377 Certificates of deposit — — — — 10,049 2 — 10,051 Commercial paper 83,155 — (1 ) 83,154 47,941 3 (4 ) 47,940 Municipal debt securities 52,669 2 (1 ) 52,670 105,933 14 (2 ) 105,945 US Treasury bond 1,607 — (1 ) 1,606 24,028 — (31 ) 23,997 Corporate debt securities 108,485 50 (154 ) 108,381 134,770 1 (106 ) 134,665 Federal agency debt securities 73,783 — (80 ) 73,703 4,711 — (1 ) 4,710 Total $ 320,480 $ 52 $ (237 ) $ 320,295 $ 335,809 $ 20 $ (144 ) $ 335,685 The amortized cost of investment securities sold is determined by the specific identification method with any realized gains or losses reflected in other (income) expense. The Company had minimal realized losses during the years ended December 31, 2015 , 2014 , and 2013 . The Company believes unrealized losses related to debt securities are not other-than-temporary and does not intend to sell these securities prior to amortized cost recoverability. The Company attempts to minimize its concentration risk with regard to its cash, cash equivalents, and investment portfolio. This is accomplished by diversifying and limiting amounts among different counterparties, the type of investment, and the amount invested in any individual security, commercial paper, or money market fund.
Inventory, Policy [Policy Text Block]	Expendable Parts, Supplies and Fuel Expendable parts, supplies and fuel inventories are valued at cost using the first-in, first-out method. Such inventories are charged to expense as they are used in operations. An obsolescence allowance for expendable parts is accrued based on the estimated lives of corresponding fleet type and salvage values. The allowance for expendable inventories was $4.6 million and $3.0 million at December 31, 2015 and 2014 respectively. Fuel inventory was $3.9 million and $5.5 million at December 31, 2015 and 2014 , respectively. Rotable aircraft parts inventories are included in flight equipment.
Internal Use Software, Policy [Policy Text Block]	Software Capitalization The Company capitalizes certain internal and external costs related to the acquisition and development of computer software during the application development stage of projects. Costs incurred during the preliminary and post-implementation stages are expensed as incurred. The Company amortizes these capitalized costs using the straight-line method over the estimated useful life of the software, which typically ranges from three to five years. The Company had unamortized computer software development costs of $38.2 million and $31.8 million as of December 31, 2015 and 2014 , respectively. Amortization expense related to computer software was $10.0 million , $6.7 million and $3.3 million for the years ended December 31, 2015 , 2014 and 2013 , respectively.
Property, Plant and Equipment, Policy [Policy Text Block]	Property and Equipment Property and equipment are recorded at cost and depreciated using the straight-line method over their estimated useful lives less an estimated salvage value. Aircraft and engines have an estimated average residual value of 14.7 percent of original cost as of December 31, 2015 ; other property and equipment are assumed to have no residual value. The depreciable lives used for the principal depreciable asset classifications are: Aircraft and related flight equipment: MD83/88 3-9 years Boeing 757-200 2 years Airbus A320 Series 10-15 years Rotable parts 7 years Buildings 25 years Equipment and leasehold improvements 3-7 years Computer hardware and software 3-5 years In estimating the useful lives and residual values of its aircraft, the Company primarily has relied upon actual experience with the same or similar aircraft types, current and projected future market information, and recommendations from other industry sources. Subsequent revisions to these estimates could be caused by changing market prices of the Company’s aircraft, changes in utilization of the aircraft, and other fleet events. These estimates are evaluated each reporting period and adjusted if necessary. Changes in the estimate for useful lives or residual values of the Company’s property and equipment could result in an acceleration of depreciation expense. Interest attributable to funds used to finance the refurbishment of aircraft prior to revenue service is capitalized as an additional cost of the related asset, provided that the refurbishment is extensive or requires an extended period of time to complete, generally longer than 90 days. Interest is capitalized at the Company’s average interest rate on long-term debt and ceases when the asset is ready for service.
Measurement of Impairment of Long-Lived Assets, Policy [Policy Text Block]	Measurement of Impairment of Long-Lived Assets The Company records impairment losses on long-lived assets used in operations, consisting principally of property and equipment, when events or changes in circumstances indicate, in management’s judgment, that the assets might be impaired, and the undiscounted future cash flows estimated to be generated by those assets are less than the carrying amount of those assets. In making these determinations, the Company utilizes certain assumptions, including, but not limited to: (i) estimated fair market value of the assets; and (ii) estimated future cash flows expected to be generated by these assets, which are based on additional assumptions such as asset utilization, length of service for which the asset will be used in operations, and estimated salvage values. For the years ended December 31, 2015 , 2014 and 2013 , the Company incurred impairment losses on spare engine parts of $1.1 million , $3.4 million and $5.3 million , respectively. In the fourth quarter 2014, the Company recorded a non-cash impairment charge of $43.3 million on its fleet of Boeing 757 aircraft, engines, and related assets as a result of its review of fleet value. The review was based on factors such as the Company's ability or intent to operate fleet types through their estimated useful lives, potential changes to the fleet residual values based on changes in market conditions for used aircraft, spare engines and parts, and potential changes to the scheduled revenue network based on competition trends and operational performance. Refer to Note 8 – Fair Value Measurements for further discussion.
Revenue Recognition, Policy [Policy Text Block]	Revenue Recognition Scheduled service revenue consists of passenger revenue generated from nonstop flights in the Company’s route network, recognized either when the travel-related service or transportation is provided or when the itinerary expires unused. Nonrefundable scheduled itineraries expire on the date of the intended flight, unless the date is extended by notification from the customer in advance. Itineraries sold for transportation not yet used, as well as unexpired credits, are included in air traffic liability. Various taxes and fees, assessed on the sale of tickets to customers, are collected by the Company serving as an agent, and remitted to taxing authorities. These taxes and fees are presented on a net basis in the Company’s consolidated statements of income and recorded as a liability until remitted to the appropriate taxing authority. Fixed fee contract revenue consists of agreements to provide charter service on a year-round and ad hoc basis. Fixed fee contract revenue is recognized when the transportation is provided. Ancillary air-related revenue is generated from fees paid by ticketed passengers and consists of baggage fees, the use of the Company’s website to purchase scheduled service transportation, advance seat assignments, and other services. Revenues from air-related charges are recognized when the transportation is provided if the product is not deemed independent of the original ticket sale. Change and cancellation fees for nonrefundable itineraries are air-related charges deemed independent of the original ticket sale, and are recognized as revenue when the sale occurs. Ancillary revenue is also generated from the sale of third party products such as hotel rooms, rental cars, ticket attractions, and other items. Revenue from the sale of third party products is recognized at the time the product is utilized, such as the time a purchased hotel room is occupied. The Company follows accounting standards for revenue arrangements with multiple deliverables to determine the amount of revenue to be recognized for each element of a bundled sale involving air-related charges and third party products in addition to airfare. Revenue from the sale of third party products is recorded net of amounts paid to wholesale providers, travel agent commissions, and transaction costs. Other revenue is generated from leased out aircraft and flight equipment, and other miscellaneous sources. Lease revenue is recognized pro-rata over the lease term.
Maintenance and Repair Costs, Policy [Policy Text Block]	Aircraft Maintenance and Repair Costs The Company accounts for non-major maintenance and repair costs incurred under the direct expense method. Under this method, maintenance and repair costs for owned and leased aircraft, excluding major maintenance activities, are charged to operating expenses as incurred. Maintenance and repair costs includes all parts, materials, line maintenance, and non-major maintenance activities required to maintain the Company's multiple fleet types. The Company accounts for major maintenance costs for MD-80 airframes and the related JT8 engines using the direct expense method. Under this method, major maintenance costs are charged to expense as incurred. This method can result in expense volatility between quarterly and annual periods, depending on the number and type of major maintenance activities performed. Scheduled maintenance activities are the most extensive in scope and are primarily based on time and usage intervals, including, but not limited to, airframe and engine overhauls. The Company has not experienced major maintenance events for its Airbus A320 series or 757-200 fleets and as such, has not yet applied a method to account for major maintenance for these aircraf
Advertising Costs, Policy [Policy Text Block]	Advertising Costs Advertising costs are charged to expense in the period incurred. Advertising expense was $12.7 million , $6.0 million and $4.2 million for the years ended December 31, 2015 , 2014 and 2013 , respectively.
Leased Aircraft Return Costs, Policy [Policy Text Block]	Leased Aircraft Return Costs The Company has been party to operating lease agreements which contain aircraft return provisions. These provisions require the Company to compensate the lessor based on specific time remaining on certain aircraft and engine components between scheduled maintenance events. A liability associated with returning leased aircraft is accrued when it is probable that a cash payment will be made and that amount is reasonably estimable. Any accrual is based on the time remaining on the lease, planned aircraft usage and other provisions included in the lease agreement, although the actual amount due to any lessor upon return is not known with certainty until lease termination. Two previously leased Airbus A320 series aircraft were purchased in 2014, at which time the lease return condition accrual of $1.4 million as of December 31, 2013 was reversed. As of December 31, 2015 , the Company has no remaining aircraft under lease agreements.
Earnings Per Share, Policy [Policy Text Block]	Earnings per Share Basic and diluted earnings per share are computed pursuant to the two-class method. Under this method, the Company attributes net income to two classes, common stock and unvested restricted stock awards. Unvested restricted stock awards granted to employees under the Company’s Long-Term Incentive Plan are considered participating securities because they receive non-forfeitable rights to cash dividends at the same rate as common stock. Diluted net income per share is calculated using the more dilutive of two methods. Under both methods, the exercise of employee stock options and stock-settled stock appreciation rights are assumed using the treasury stock method. The assumption of vesting of restricted stock, however, differs as described below: 1. Assume vesting of restricted stock using the treasury stock method. 2. Assume unvested restricted stock awards are not vested, and allocate earnings to common shares and unvested restricted stock awards using the two-class method. For the years ended December 31, 2015 , 2014 and 2013 , the second method above was used in the computation because it was more dilutive than the first method. The following table sets forth the computation of net income per share on a basic and diluted basis for the periods indicated (in thousands, except per share amounts): Year ended December 31, 2015 2014 2013 Basic: Net income attributable to Allegiant Travel Company $ 220,374 $ 86,689 $ 92,273 Less net income allocated to participating securities (961 ) (293 ) (381 ) Net income attributable to common stock $ 219,413 $ 86,396 $ 91,892 Net income per share, basic $ 12.97 $ 4.87 $ 4.85 Weighted-average shares outstanding 16,923 17,729 18,936 Diluted: Net income attributable to Allegiant Travel Company $ 220,374 $ 86,689 $ 92,273 Less net income allocated to participating securities (958 ) (292 ) (378 ) Net income attributable to common stock $ 219,416 $ 86,397 $ 91,895 Net income per share, diluted $ 12.94 $ 4.86 $ 4.82 Weighted-average shares outstanding 16,923 17,729 18,936 Dilutive effect of stock options, restricted stock and stock-settled stock appreciation rights 69 88 154 Adjusted weighted-average shares outstanding under treasury stock method 16,992 17,817 19,090 Participating securities excluded under two-class method (30 ) (35 ) (40 ) Adjusted weighted-average shares outstanding under two-class method 16,962 17,782 19,050 Stock awards outstanding of 28,789 , 75,233 , and 91,028 shares for 2015 , 2014 , and 2013 , respectively, were excluded from the computation of diluted earnings per share as they were antidilutive.
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]	Share-Based Compensation The Company accounts for share-based compensation in accordance with accounting standards which require the compensation cost related to share-based payment transactions be recognized in the Company’s consolidated statements of income. The cost is measured at the grant date, based on the calculated fair value of the award using the Black-Scholes option pricing model for stock options and cash-settled SARs, and is remeasured monthly for cash-settled SARs. Cost is based on the closing share price of the Company’s stock on the grant date for restricted stock awards. The cost is recognized as an expense over the employee’s requisite service period, the vesting period of the award, which is generally three years. The Company’s share-based employee compensation plan is more fully discussed in Note 12—Employee Benefit Plans.
Income Tax, Policy [Policy Text Block]	Income Taxes The Company recognizes deferred income taxes based on the asset and liability method required by accounting standards. Deferred tax assets and liabilities are determined based on the timing differences between book basis for financial reporting purposes and tax basis of the asset and liability and measured using the enacted tax rates. A valuation allowance for deferred tax assets is provided if it is more likely than not that some portion or all of the deferred tax assets will not be realized. The Company determines the net non-current deferred tax assets or liabilities separately for federal, state, foreign and other local jurisdictions. The Company’s income tax returns are subject to examination by the Internal Revenue Service (“IRS”) and other tax authorities in the jurisdictions where the Company operates. The Company assesses potentially unfavorable outcomes of such examinations based on the criteria set forth in uncertain tax position accounting standards. The accounting standards prescribe a minimum recognition threshold a tax position is required to meet before being recognized in the financial statements. Accounting standards for income taxes utilize a two-step approach for evaluating tax positions. Recognition (Step I) occurs when the Company concludes that a tax position, based on its technical merits, is more likely than not to be sustained upon examination. Measurement (Step II) is only addressed if the position is deemed to be more likely than not to be sustained. Under Step II, the tax benefit is measured as the largest amount of benefit that is greater than 50 percent likely of being realized upon settlement. The tax positions failing to qualify for initial recognition are recognized in the first subsequent interim period they meet the “more likely than not” standard. If it is subsequently determined that a previously recognized tax position no longer meets the “more likely than not” standard, it is required that the tax position be derecognized. As applicable, the Company will recognize accrued penalties and interest related to unrecognized tax benefits in the provision for income taxes.
New Accounting Pronouncements, Policy [Policy Text Block]	Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU 2014-09, intended to create a unified model to determine when and how revenue is recognized. The core principle is that a company should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In July 2015, the FASB deferred the effective date by one year, to December 15, 2017, for annual and interim periods beginning after that date. Early adoption is also permitted but not before the original effective date of annual periods beginning after December 15, 2016. The Company is evaluating the impact on its financial statements of adopting this new accounting standard and plans to provide additional information regarding its expected financial impact at a later date. In April 2015, the FASB issued ASU 2015-03, which amends existing guidance and requires the presentation of debt issuance costs on the balance sheet as a reduction of the carrying amount of the related debt liability rather than as a deferred charge, effective for fiscal years, and interim periods within those years beginning on or after December 15, 2015 and early adoption is permitted. The Company retrospectively adopted this standard as of December 31, 2015. Debt issuance costs previously reflected on the balance sheet in deposits and other assets, are now reflected as a reduction to long-term debt, in the amount of $4.5 million and $4.3 million as of December 31, 2015 and December 31, 2014, respectively. In November 2015, the FASB issued ASU 2015-17, requiring all deferred tax assets and liabilities, and any related valuation allowance, to be classified as non-current on the balance sheet, effective for fiscal years, and interim periods within those years, beginning on or after December 15, 2016 and early adoption is permitted. The purpose of the classification change is to simplify the presentation of deferred income taxes on the Consolidated Balance Sheet. The Company has elected to prospectively adopt this accounting principle as of December 31, 2015. Prior periods in the consolidated financial statements have not been retrospectively adjusted.

Summary of Significant Accoun25

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Unrealized Gain (Loss) on Investments	Investment securities consisted of the following (in thousands): As of December 31, 2015 As of December 31, 2014 Net Unrealized Net Unrealized Cost Gains (Losses) Market Value Cost Gains (Losses) Market Value Money market funds $ 781 $ — $ — $ 781 $ 8,377 $ — $ — $ 8,377 Certificates of deposit — — — — 10,049 2 — 10,051 Commercial paper 83,155 — (1 ) 83,154 47,941 3 (4 ) 47,940 Municipal debt securities 52,669 2 (1 ) 52,670 105,933 14 (2 ) 105,945 US Treasury bond 1,607 — (1 ) 1,606 24,028 — (31 ) 23,997 Corporate debt securities 108,485 50 (154 ) 108,381 134,770 1 (106 ) 134,665 Federal agency debt securities 73,783 — (80 ) 73,703 4,711 — (1 ) 4,710 Total $ 320,480 $ 52 $ (237 ) $ 320,295 $ 335,809 $ 20 $ (144 ) $ 335,685
Estimated Useful Lives	Property and equipment are recorded at cost and depreciated using the straight-line method over their estimated useful lives less an estimated salvage value. Aircraft and engines have an estimated average residual value of 14.7 percent of original cost as of December 31, 2015 ; other property and equipment are assumed to have no residual value. The depreciable lives used for the principal depreciable asset classifications are: Aircraft and related flight equipment: MD83/88 3-9 years Boeing 757-200 2 years Airbus A320 Series 10-15 years Rotable parts 7 years Buildings 25 years Equipment and leasehold improvements 3-7 years Computer hardware and software 3-5 years Property and equipment consisted of the following (in thousands): As of December 31, 2015 As of December 31, 2014 Flight equipment $ 1,123,115 $ 947,082 Computer hardware and software 78,200 58,173 Ground property and equipment 72,078 42,743 Total property and equipment 1,273,393 1,047,998 Less accumulated depreciation and amortization (387,451 ) (309,215 ) Property and equipment, net $ 885,942 $ 738,783
Schedule of Earnings Per Share, Basic and Diluted	The following table sets forth the computation of net income per share on a basic and diluted basis for the periods indicated (in thousands, except per share amounts): Year ended December 31, 2015 2014 2013 Basic: Net income attributable to Allegiant Travel Company $ 220,374 $ 86,689 $ 92,273 Less net income allocated to participating securities (961 ) (293 ) (381 ) Net income attributable to common stock $ 219,413 $ 86,396 $ 91,892 Net income per share, basic $ 12.97 $ 4.87 $ 4.85 Weighted-average shares outstanding 16,923 17,729 18,936 Diluted: Net income attributable to Allegiant Travel Company $ 220,374 $ 86,689 $ 92,273 Less net income allocated to participating securities (958 ) (292 ) (378 ) Net income attributable to common stock $ 219,416 $ 86,397 $ 91,895 Net income per share, diluted $ 12.94 $ 4.86 $ 4.82 Weighted-average shares outstanding 16,923 17,729 18,936 Dilutive effect of stock options, restricted stock and stock-settled stock appreciation rights 69 88 154 Adjusted weighted-average shares outstanding under treasury stock method 16,992 17,817 19,090 Participating securities excluded under two-class method (30 ) (35 ) (40 ) Adjusted weighted-average shares outstanding under two-class method 16,962 17,782 19,050

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Schedule Of Property Plant And Equipment	Property and equipment are recorded at cost and depreciated using the straight-line method over their estimated useful lives less an estimated salvage value. Aircraft and engines have an estimated average residual value of 14.7 percent of original cost as of December 31, 2015 ; other property and equipment are assumed to have no residual value. The depreciable lives used for the principal depreciable asset classifications are: Aircraft and related flight equipment: MD83/88 3-9 years Boeing 757-200 2 years Airbus A320 Series 10-15 years Rotable parts 7 years Buildings 25 years Equipment and leasehold improvements 3-7 years Computer hardware and software 3-5 years Property and equipment consisted of the following (in thousands): As of December 31, 2015 As of December 31, 2014 Flight equipment $ 1,123,115 $ 947,082 Computer hardware and software 78,200 58,173 Ground property and equipment 72,078 42,743 Total property and equipment 1,273,393 1,047,998 Less accumulated depreciation and amortization (387,451 ) (309,215 ) Property and equipment, net $ 885,942 $ 738,783
Types of Commercial Aircraft [Table Text Block]	The following table summarizes the Company's total in-service aircraft fleet as of December 31, 2015 : Aircraft Type Owned (1) Seating Capacity Average Age MD-83/88 51 166 26.0 Boeing 757-200 5 215 22.8 Airbus A319 (2) 10 156 11.0 Airbus A320 (3) 14 177 15.9 Total aircraft 80

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following (in thousands): As of December 31, 2015 As of December 31, 2014 Salaries, wages and benefits $ 37,545 $ 30,949 Dividends 27,728 43,703 Station expenses 11,668 7,683 Maintenance and repairs 7,287 4,727 Passenger fees 9,007 8,219 Passenger taxes 1,415 705 Interest 7,900 8,875 Other accruals 6,912 5,941 Total accrued liabilities $ 109,462 $ 110,802

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Summary of Long-Term Debt	Long-term debt consisted of the following (in thousands): As of December 31, 2015 As of December 31, 2014 Fixed-rate notes payable due through 2020 $ 341,738 $ 343,625 Variable-rate notes payable due through 2020 299,940 245,169 Total long-term debt, net of related costs 641,678 588,794 Less current maturities 74,069 52,605 Long-term debt, net of current maturities and related costs $ 567,609 $ 536,189

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Assets Measured at Fair Value On a Recurring Basis	Financial instruments measured at fair value on a recurring basis (in thousands): Description As of Level 1 Level 2 Cash equivalents Commercial paper $ 8,426 $ — $ 8,426 Money market funds 781 781 — Municipal debt securities 754 — 754 Total cash equivalents 9,961 781 9,180 Short-term Corporate debt securities 80,957 — 80,957 Municipal debt securities 47,073 — 47,073 Commercial paper 74,728 — 74,728 Federal agency debt securities 42,825 — 42,825 Total short-term 245,583 — 245,583 Long-term Federal agency debt securities 30,878 — 30,878 Corporate debt securities 27,425 — 27,425 Municipal debt securities 4,843 — 4,843 Derivative instruments 2,480 — 2,480 US Treasury Bond 1,606 — 1,606 Total long-term 67,232 — 67,232 Total financial instruments $ 322,776 $ 781 $ 321,995 Description As of Level 1 Level 2 Cash equivalents Money market funds $ 8,377 $ 8,377 $ — Municipal debt securities 101 — 101 Total cash equivalents 8,478 8,377 101 Short-term Corporate debt securities 103,961 — 103,961 Municipal debt securities 103,155 — 103,155 Commercial paper 47,940 — 47,940 Certificates of deposit 10,051 — 10,051 Federal agency debt securities 4,710 — 4,710 Total short-term 269,817 — 269,817 Long-term Corporate debt securities 30,704 — 30,704 Government debt securities 23,997 — 23,997 Municipal debt securities 2,689 — 2,689 Derivative instruments 1,858 — 1,858 Total long-term 59,248 — 59,248 Total financial instruments $ 337,543 $ 8,377 $ 329,166
Debt Instrument, Fair Value Disclosure	Carrying value and estimated fair value of long-term debt, including current maturities (in thousands): As of December 31, 2015 As of December 31, 2014 Carrying value Estimated fair value Carrying value Estimated Fair Value Level Publicly held debt $ 300,000 $ 299,250 $ 300,000 $ 304,875 2 Non-publicly held debt 346,179 327,321 293,099 270,490 3 Total long-term debt $ 646,179 $ 626,571 $ 593,099 $ 575,365

Income Taxes Income Taxes (Tabl

Income Taxes Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	The components of income before taxes for domestic and foreign operations consisted of the following (in thousands): Twelve Months Ended December 31, 2015 2014 2013 Domestic $ 331,813 $ 129,553 $ 146,680 Foreign 14,906 7,578 — Total $ 346,719 $ 137,131 $ 146,680
Schedule of Components of Income Tax Expense (Benefit)	The provision for income taxes is composed of the following (in thousands): Year Ended December 31, 2015 2014 2013 Current: Federal $ 108,119 $ 53,156 $ 52,732 State 6,501 4,645 4,114 Foreign 996 854 — Total current 115,616 58,655 56,846 Deferred: Federal 9,458 (8,557 ) (1,811 ) State 125 (247 ) (134 ) Foreign 1,190 977 — Total deferred 10,773 (7,827 ) (1,945 ) Total income tax provision $ 126,389 $ 50,828 $ 54,901
Schedule of Effective Income Tax Rate Reconciliation	The effective tax rate on income before income taxes differed from the federal statutory income tax rate as follows (in thousands): Year Ended December 31, 2015 2014 2013 Income tax expense at federal statutory rate $ 120,847 $ 48,007 $ 51,362 State income taxes, net of federal income tax benefit 4,293 2,587 2,654 Other 1,249 234 885 Total income tax expense $ 126,389 $ 50,828 $ 54,901
Schedule of Deferred Tax Assets and Liabilities	The major components of the Company’s net deferred tax assets and liabilities are as follows (in thousands): As of December 31, 2015 2014 Deferred tax assets: Accrued vacation $ 1,339 $ 1,149 Accrued bonus 8,189 4,633 State taxes 2,396 1,484 Accrued property taxes 1,149 1,329 Other 6,940 2,619 Stock-based compensation expense 2,923 2,936 Federal net operating loss — 1,063 Less: valuation allowance — (1,330 ) Total deferred tax assets 22,936 13,883 Deferred tax liabilities: Prepaid expenses 5,314 5,482 Depreciation 60,979 44,116 Foreign deferred 2,223 909 Total deferred tax liabilities 68,516 50,507 Net deferred tax liabilities $ 45,580 $ 36,624

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2015
Employee Benefit Plans [Abstract]
Schedule of Unrecognized Compensation Cost, Nonvested Awards [Table Text Block]	The unrecognized compensation cost, and weighted-average period over which the cost is expected to be recognized for non-vested awards as of December 31, 2015 , are presented below: Unrecognized Compensation Cost (thousands) Weighted Average Period (years) Restricted stock $ 6,760 1.69 Cash-settled SARs 3,685 1.38 Stock options 340 1.13 Total $ 10,785 1.57
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Table Text Block]	The following range of assumptions in the Black-Scholes option pricing model was used to determine fair value at the years ended below: 2015 2014 2013 Weighted-average volatility 30.2 % 29.3 % 30.5 % Expected term (in years) 0.3 - 2.5 1.4 - 2.5 0.3 - 2.5 Risk-free interest rate 0.3% - 1.2% 0.4% - 0.9% 0.3% - 0.5% Dividend yield 0.49% - 2.22% 1.80 % —
Schedule of Share-based Compensation, Stock Options, Activity	A summary of option activity as of December 31, 2015 , 2014 and 2013, and changes during the years then ended, is presented below: Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (years) Aggregate Intrinsic Value (thousands) Outstanding at December 31, 2012 228,690 $ 36.89 Granted 108,041 81.77 Exercised (53,100 ) 38.03 Outstanding at December 31, 2013 283,631 49.48 3.38 $ 14,507 Granted 50,630 108.59 Exercised (1) (237,912 ) 38.39 Forfeited (7,600 ) 20.42 Outstanding at December 31, 2014 88,749 69.43 3.29 $ 7,180 Exercised (36,968 ) 52.06 Forfeited (3,000 ) 3.50 Outstanding at December 31, 2015 48,781 $ 86.65 2.62 $ 3,960 Fully vested and expected to vest at December 31, 2015 39,710 $ 81.71 2.50 $ 3,245 Exercisable at December 31, 2015 19,250 $ 58.11 1.98 $ 1,119
Schedule of Nonvested Restricted Stock Units Activity	A summary of the status of the Company’s non-vested restricted stock grants during the years ended December 31, 2015 , 2014 and 2013 is presented below: Shares Weighted Average Grant Date Fair Value Non-vested at December 31, 2012 128,029 $ 52.63 Granted 85,196 84.36 Vested (64,426 ) 52.57 Forfeited (3,567 ) 82.87 Non-vested at December 31, 2013 145,232 62.61 Granted 54,731 109.66 Vested (1) (90,567 ) 75.31 Forfeited (10,614 ) 79.36 Non-vested at December 31, 2014 98,782 91.15 Granted 47,810 178.68 Vested (54,825 ) 83.35 Forfeited (8,810 ) 130.35 Non-vested at December 31, 2015 82,957 $ 155.30
Schedule Of Cash Settled Stock Appreciation Rights Activity	A summary of cash-settled SARs awards activity during the year ended December 31, 2015 is presented below: Cash-Settled SARs Weighted Average Grant Date Fair Value 3/25/11 Grant Outstanding at January 1, 2015 23,893 $ 19.01 Exercised (10,108 ) 19.01 Forfeited — — Outstanding at December 31, 2015 13,785 $ 19.01 Exercisable at December 31, 2015 13,785 $ 19.01 3/8/13 Grant Outstanding at January 1, 2015 46,545 $ 20.92 Exercised (24,283 ) 20.92 Forfeited (4,554 ) 20.92 Outstanding at December 31, 2015 17,708 $ 20.92 Exercisable at December 31, 2015 3,035 $ 20.92 3/6/14 Grant Outstanding at January 1, 2015 49,075 $ 25.68 Exercised (9,055 ) 25.68 Forfeited (7,790 ) 25.68 Outstanding at December 31, 2015 32,230 $ 25.68 Exercisable at December 31, 2015 7,302 25.68 2/25/15 Grant Outstanding at January 1, 2015 — $ — Granted 77,396 34.53 Forfeited (9,378 ) 34.53 Outstanding at December 31, 2015 68,018 $ 34.53 Exercisable at December 31, 2015 — — As of December 31, 2015 , the accrued liability related to these awards was $4.9 million .

Summary of Significant Accoun32

Summary of Significant Accounting Policies - (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Accrued Aircraft Lease Return Costs		$ 1,400
Advertising Expense	$ 12,665	6,022	$ 4,160
Asset Impairment Charges	0	43,280	0
Capitalized Computer Software, Net	38,206	31,840
Capitalized Computer Software, Amortization	$ 10,006	$ 6,678	$ 3,347
Significant Change in Unrecognized Tax Benefits, Nature of Event	50.00%

Summary of Significant Accoun33

Summary of Significant Accounting Policies Investment Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities
Equity Method Investment, Ownership Percentage	50.00%
Cost	$ 320,480	$ 335,809
Gains	52	20
Losses	(237)	(144)
Market Value	320,295	335,685
Money market funds
Schedule of Available-for-sale Securities
Cost	781	8,377
Gains	0	0
Losses	0	0
Market Value	781	8,377
Certificates of deposit
Schedule of Available-for-sale Securities
Cost	0	10,049
Gains	0	2
Losses	0	0
Market Value	0	10,051
Commercial paper
Schedule of Available-for-sale Securities
Cost	83,155	47,941
Gains	0	3
Losses	(1)	(4)
Market Value	83,154	47,940
Municipal bonds
Schedule of Available-for-sale Securities
Cost	52,669	105,933
Gains	2	14
Losses	(1)	(2)
Market Value	52,670	105,945
US Government Corporations and Agencies Securities
Schedule of Available-for-sale Securities
Cost	1,607	24,028
Gains	0	0
Losses	(1)	(31)
Market Value	1,606	23,997
Corporate debt securities
Schedule of Available-for-sale Securities
Cost	108,485	134,770
Gains	50	1
Losses	(154)	(106)
Market Value	108,381	134,665
Government debt securities
Schedule of Available-for-sale Securities
Cost	73,783	4,711
Gains	0	0
Losses	(80)	(1)
Market Value	$ 73,703	$ 4,710

Summary of Significant Accoun34

Summary of Significant Accounting Policies Property, Plant and Equipment, Salvage Value, Percentage (Details)	12 Months Ended
	Dec. 31, 2015
Aircraft And Engines
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Salvage Value, Percentage	14.70%
Rotable Parts
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P7Y
Building
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P25Y
Equipment And Leasehold Improvements | Minimum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P3Y
Equipment And Leasehold Improvements | Maximum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P7Y
Computer Hardware and Software | Minimum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P3Y
Computer Hardware and Software | Maximum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P5Y
MD-80 Aircraft | Aircraft And Engines | Minimum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P3Y
MD-80 Aircraft | Aircraft And Engines | Maximum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P9Y
Boeing 757 | Aircraft And Engines
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P2Y
Airbus A320 Aircraft Series [Member] | Aircraft And Engines | Minimum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P10Y
Airbus A320 Aircraft Series [Member] | Aircraft And Engines | Maximum
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	P15Y

Summary of Significant Accoun35

Summary of Significant Accounting Policies Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Net income attributable to Allegiant Travel Company	$ 220,374	$ 86,689	$ 92,273
Less net income allocated to participating securities	(961)	(293)	(381)
Net income attributable to common stock	$ 219,413	$ 86,396	$ 91,892
Net income per share, basic	$ 12.97	$ 4.87	$ 4.85
Weighted-average shares outstanding	16,923	17,729	18,936
Net income attributable to common stock	$ 219,416	$ 86,397	$ 91,895
Less net income allocated to participating securities	$ (958)	$ (292)	$ (378)
Net income per share, diluted	$ 12.94	$ 4.86	$ 4.82
Dilutive effect of stock options, restricted stock and stock-settled stock appreciation rights	69	88	154
Adjusted weighted-average shares outstanding under treasury stock method	16,992	17,817	19,090
Participating securities excluded under two-class method	(30)	(35)	(40)
Adjusted weighted-average shares outstanding under two-class method	16,962	17,782	19,050

Summary of Significant Accoun36

Summary of Significant Accounting Policies Earnings Per Share Textual (Details) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	28,789	75,233	91,028

Summary of Significant Accoun37

Summary of Significant Accounting Policies Measurement of Impairment of Long-Lived Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairment Charges	$ 0	$ 43,280	$ 0
Spare engine parts
Impaired Long-Lived Assets Held and Used [Line Items]
Asset Impairment Charges	$ 1,107	$ 3,437	$ 5,315

Summary of Significant Accoun38

Summary of Significant Accounting Policies Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt Issuance Cost	$ 4,500	$ 4,300

Summary of Significant Accoun39

Summary of Significant Accounting Policies Expendable Parts, Supplies and Fuel (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Expendable Parts, Supplies and Fuel [Abstract]
Inventory Valuation Reserves	$ 4,600	$ 3,000
Expendable parts, supplies and fuel, net of allowance	$ 3,900	$ 5,500

Property and Equipment (Details

Property and Equipment (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Aug. 31, 2014aircraft	Dec. 31, 2015USD ($)aircraft	Dec. 31, 2014USD ($)
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		80
Flight Equipment, Gross | $		$ 1,123,115	$ 947,082
Computer Hardware and Software | $		78,200	58,173
Ground property and equipment | $		72,078	42,743
Property, Plant and Equipment, Gross | $		1,273,393	1,047,998
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment | $		(387,451)	(309,215)
Property, Plant and Equipment, Net | $		$ 885,942	$ 738,783
MD-80 Aircraft
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		51
Boeing 757
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		5
Airbus A320
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		14
Airbus A320 | Asset not in service [Member]
Property, Plant and Equipment [Line Items]
Number of Aircraft Owned		2
Airbus A319
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		10
Airbus A319 | Lease Agreements
Property, Plant and Equipment [Line Items]
Number of Aircraft Owned		12
Airbus A319 | Asset not in service [Member]
Property, Plant and Equipment [Line Items]
Number of Aircraft Owned		1
Airbus A320 Aircraft Series | Lease Agreements
Property, Plant and Equipment [Line Items]
Number of Aircraft Owned	8

Property and Equipment Total Ai

Property and Equipment Total Aircraft Fleet (Details)	1 Months Ended	12 Months Ended
	Aug. 31, 2014aircraft	Dec. 31, 2015aircraft	Dec. 31, 2014aircraft
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		80
Number Of Aircraft Leased			2
MD-80 Aircraft
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		51
Average Age of Aircraft		26 years
Boeing 757
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		5
Average Age of Aircraft		22 years 9 months 18 days
Airbus A319
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		10
Average Age of Aircraft		11 years
Airbus A320
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		14
Average Age of Aircraft		15 years 10 months 24 days
Lease Agreements | Airbus A319
Property, Plant and Equipment [Line Items]
Number of Aircraft Owned		12
Lease Agreements | Airbus A320 Aircraft Series
Property, Plant and Equipment [Line Items]
Number of Aircraft Owned	8
Seating Capacity | MD-80 Aircraft
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		166
Seating Capacity | Boeing 757
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		215
Seating Capacity | Airbus A319
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		156
Seating Capacity | Airbus A320
Property, Plant and Equipment [Line Items]
Number of Aircraft in Fleet		177
Asset not in service [Member] | Airbus A319
Property, Plant and Equipment [Line Items]
Number of Aircraft Owned		1
Asset not in service [Member] | Airbus A320
Property, Plant and Equipment [Line Items]
Number of Aircraft Owned		2

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accrued Liabilities, Current [Abstract]
Salaries, wages and benefits	$ 37,545	$ 30,949
Maintenance and repairs	7,287	4,727
Passenger fees	9,007	8,219
Passenger taxes	1,415	705
Station expenses	11,668	7,683
Interest	7,900	8,875
Dividends	27,728	43,703
Other accruals	6,912	5,941
Accrued liabilities	$ 109,462	$ 110,802

Accrued Liabilities Textual (De

Accrued Liabilities Textual (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Dividends Payable, Amount Per Share		$ 2.50	$ 2.25
Asset Impairment Charges	$ 0	$ 43,280	$ 0
Special Dividend
Dividends Payable, Amount Per Share	$ 1.65

Long-Term Debt (Detail)

Long-Term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Notes Payable	$ 646,179	$ 593,099
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	74,106
Long-term Debt, Maturities, Repayments of Principal in Year Two	76,387
Long-term Debt, Maturities, Repayments of Principal in Year Three	133,056
Long-term Debt, Maturities, Repayments of Principal in Year Four	336,900
Long-term Debt, Maturities, Repayments of Principal in Year Five	21,173
Long-term Debt, Maturities, Repayments of Principal after Year Five	0
Total long-term debt, net of related costs	641,678	588,794
Long-term Debt, Current Maturities	74,069	52,605
Long-term Debt, Excluding Current Maturities	567,609	536,189
Fixed-rate notes payable due through 2020
Notes Payable	341,738	343,625
Variable-rate notes payable due through 2020
Notes Payable	$ 299,940	$ 245,169

Long-Term Debt - Components of

Long-Term Debt - Components of Long-Term Debt (Detail)	3 Months Ended	6 Months Ended		9 Months Ended	12 Months Ended
	Mar. 31, 2015USD ($)	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)aircraft	Sep. 30, 2015USD ($)	Dec. 31, 2015USD ($)aircraft	Dec. 31, 2014USD ($)	May. 31, 2014USD ($)aircraft	Apr. 30, 2014USD ($)
Debt Instrument [Line Items]
Repayments of Debt					$ 4,600,000
Secured Long-term Debt, Noncurrent					641,678,000	$ 588,794,000
Debt Instrument, Collateral			12
Line of Credit Facility, Description					$ 56,000,000
Line of Credit Facility, Interest Rate Description					1.85%
Repayments of Secured Debt			$ 8,500,000
Due March 2020
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.70%
Due December 2020
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent					$ 28,000,000
Debt Instrument, Interest Rate, Stated Percentage					1.70%
Due July 2019
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.50%
Unsecured Long-term Debt, Noncurrent			$ 300,000,000
Due March 2017
Debt Instrument [Line Items]
Repayments of Debt			$ 121,100,000
DebtInstrumentLIBORPercentageRateMinimum			1.50%
Due November 2018
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent			$ 142,000,000
Debt Instrument, Interest Rate, Stated Percentage			3.08%
Due April 2018
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent								$ 45,300,000
Debt Instrument, Interest Rate, Stated Percentage								2.95%
Due May 2018
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent							$ 40,000,000
Debt Instrument, Interest Rate, Stated Percentage							2.95%
Due September 2020
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent				$ 29,000,000
Debt Instrument, Interest Rate, Stated Percentage				1.75%
Due June 2020
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		1.70%
Airbus A319
Debt Instrument [Line Items]
Debt Instrument, Collateral			1
Airbus A319 | Due March 2020
Debt Instrument [Line Items]
Debt Instrument, Collateral	2
Airbus A319 | Due December 2020
Debt Instrument [Line Items]
Debt Instrument, Collateral					2
Airbus A319 | Due September 2020
Debt Instrument [Line Items]
Debt Instrument, Collateral				2
Airbus A319 | Due June 2020
Debt Instrument [Line Items]
Debt Instrument, Collateral		2
Boeing 757
Debt Instrument [Line Items]
Number Of Aircraft Used As Collateral | aircraft			2		1		6
Notes Payable, One Point Seven Percent, Due June Two Thousand Twenty [Member] | Due June 2020
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent		$ 26,500,000
Notes Payable, One Point Seven Percent, Due March Two Thousand Twenty [Member] | Due March 2020
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	$ 30,000,000
Notes Payable, Two Point Eight Six Percent, Due March Two Thousand Twenty [Member] | Due March 2020
Debt Instrument [Line Items]
Secured Long-term Debt, Noncurrent	$ 7,500,000
Debt Instrument, Interest Rate, Stated Percentage	2.86%

Leases (Details)

Leases (Details) $ in Thousands	1 Months Ended	6 Months Ended	12 Months Ended
	Aug. 31, 2014aircraft	Jun. 30, 2014	Dec. 31, 2015USD ($)ft²	Dec. 31, 2014USD ($)aircraft	Dec. 31, 2013USD ($)
Operating Leased Assets [Line Items]
Operating Leases, Rent Expense			$ 7,870	$ 8,813	$ 13,098
Aircraft lease rentals			2,326	$ 15,945	9,227
Number Of Aircraft Leased | aircraft				2
Sub-Service Expense			2,100	$ 14,794	4,200
Debt Instrument, Collateral		12
Airbus A320 Aircraft Series
Operating Leased Assets [Line Items]
Aircraft lease rentals				$ 1,025	$ 5,500
Airbus A319
Operating Leased Assets [Line Items]
Debt Instrument, Collateral		1
Building
Operating Leased Assets [Line Items]
2,016			5,081
2,017			3,612
2,018			2,327
2,019			1,673
2,020			1,254
Thereafter			3,346
Airport fee payments
Operating Leased Assets [Line Items]
2,016			11,023
2,017			5,872
Thereafter			$ 821
Airbus A320 Aircraft Series | Lease Agreements
Operating Leased Assets [Line Items]
Number of Aircraft Owned | aircraft	8
Number of Aircraft Delivered | aircraft	2
Building 3
Operating Leased Assets [Line Items]
Area of Real Estate Property | ft²			87,000
Building 2
Operating Leased Assets [Line Items]
Area of Real Estate Property | ft²			10,000
Building 1
Operating Leased Assets [Line Items]
Area of Real Estate Property | ft²			70,000

Leases Future Minimum Lease Pay

Leases Future Minimum Lease Payments Under Operating Leases (Details) - Building $ in Thousands	Dec. 31, 2015USD ($)
Operating Leased Assets [Line Items]
2,016	$ 5,081
2,017	3,612
2,018	2,327
2,019	1,673
2,020	1,254
Thereafter	$ 3,346

Leases Future Minimum Airport F

Leases Future Minimum Airport Fee Payments (Details) - Airport fee payments $ in Thousands	Dec. 31, 2015USD ($)
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 11,023
Operating Leases, Future Minimum Payments, Due in Two Years	5,872
Operating Leases, Future Minimum Payments, Due Thereafter	$ 821

Stockholders' Equity (Detail)

Stockholders' Equity (Detail) - USD ($) $ / shares in Units, $ in Thousands	Jan. 08, 2016	Jan. 06, 2015	Jan. 03, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stock Repurchased During Period, Shares (in Shares)				694,685	1,268,289	927,006
Treasury Stock Acquired, Average Cost Per Share (in Dollars per share)				$ 186.35	$ 109.68	$ 90,030
Stock Repurchased During Period, Value				$ 129,455	$ 139,105	$ 83,462
Stock Repurchase Program, Authorized Amount				54,100
Payments for Repurchase of Common Stock				129,455	$ 139,105	$ 83,607
Dividends Payable, Amount Per Share					$ 2.50	$ 2.25
Dividends		$ 43,703	$ 41,787	$ 18,736
Subsequent Event
Dividends	$ 27,700
Recurring Dividend
Dividends Payable, Amount Per Share				$ 1.10
Special Dividend
Dividends Payable, Amount Per Share				$ 1.65

Fair Value Measurements (Detail

Fair Value Measurements (Detail) - Fair Value Measurements at Reporting Date Using - USD ($) $ in Thousands	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Investment Securities	$ 320,295		$ 335,685
Municipal debt securities | Long-term investments
Investment Securities	4,843
Municipal debt securities | Fair Value, Inputs, Level 1 | Long-term investments
Investment Securities	0
Municipal debt securities | Fair Value, Inputs, Level 2 | Long-term investments
Investment Securities	4,843
US Treasury and Government [Member] | Long-term investments
Investment Securities			23,997
US Treasury and Government [Member] | Fair Value, Inputs, Level 1 | Long-term investments
Investment Securities			0
US Treasury and Government [Member] | Fair Value, Inputs, Level 2 | Long-term investments
Investment Securities			23,997
US Treasury Bond Securities [Member] | Long-term investments
Investment Securities	1,606
US Treasury Bond Securities [Member] | Fair Value, Inputs, Level 1 | Long-term investments
Investment Securities	0
US Treasury Bond Securities [Member] | Fair Value, Inputs, Level 2 | Long-term investments
Investment Securities	1,606
Fair Value, Measurements, Recurring
Cash Equivalents			8,478
Investment Securities	322,776		337,543
Fair Value, Measurements, Recurring | Short-term investments
Investment Securities	245,583		269,817
Fair Value, Measurements, Recurring | Long-term investments
Investment Securities	67,232		59,248
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Cash Equivalents			8,377
Investment Securities	781		8,377
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Short-term investments
Investment Securities	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Long-term investments
Investment Securities	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Cash Equivalents			101
Investment Securities	321,995		329,166
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Short-term investments
Investment Securities	245,583		269,817
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Long-term investments
Investment Securities	67,232		59,248
Fair Value, Measurements, Recurring | Money market funds
Cash Equivalents			8,377
Fair Value, Measurements, Recurring | Money market funds | Fair Value, Inputs, Level 1
Cash Equivalents			8,377
Fair Value, Measurements, Recurring | Money market funds | Fair Value, Inputs, Level 2
Cash Equivalents			0
Fair Value, Measurements, Recurring | Commercial paper | Short-term investments
Investment Securities	74,728		47,940
Fair Value, Measurements, Recurring | Commercial paper | Fair Value, Inputs, Level 1 | Short-term investments
Investment Securities	0		0
Fair Value, Measurements, Recurring | Commercial paper | Fair Value, Inputs, Level 2 | Short-term investments
Investment Securities	74,728		47,940
Fair Value, Measurements, Recurring | US Government Corporations and Agencies Securities | Short-term investments
Investment Securities	42,825		4,710
Fair Value, Measurements, Recurring | US Government Corporations and Agencies Securities | Long-term investments
Investment Securities	30,878
Fair Value, Measurements, Recurring | US Government Corporations and Agencies Securities | Fair Value, Inputs, Level 1 | Short-term investments
Investment Securities	0		0
Fair Value, Measurements, Recurring | US Government Corporations and Agencies Securities | Fair Value, Inputs, Level 1 | Long-term investments
Investment Securities	0
Fair Value, Measurements, Recurring | US Government Corporations and Agencies Securities | Fair Value, Inputs, Level 2 | Short-term investments
Investment Securities	42,825		4,710
Fair Value, Measurements, Recurring | US Government Corporations and Agencies Securities | Fair Value, Inputs, Level 2 | Long-term investments
Investment Securities	30,878
Fair Value, Measurements, Recurring | Municipal debt securities
Cash Equivalents			101
Fair Value, Measurements, Recurring | Municipal debt securities | Short-term investments
Investment Securities	47,073		103,155
Fair Value, Measurements, Recurring | Municipal debt securities | Long-term investments
Investment Securities			2,689
Fair Value, Measurements, Recurring | Municipal debt securities | Fair Value, Inputs, Level 1
Cash Equivalents			0
Fair Value, Measurements, Recurring | Municipal debt securities | Fair Value, Inputs, Level 1 | Short-term investments
Investment Securities	0		0
Fair Value, Measurements, Recurring | Municipal debt securities | Fair Value, Inputs, Level 1 | Long-term investments
Investment Securities			0
Fair Value, Measurements, Recurring | Municipal debt securities | Fair Value, Inputs, Level 2
Cash Equivalents			101
Fair Value, Measurements, Recurring | Municipal debt securities | Fair Value, Inputs, Level 2 | Short-term investments
Investment Securities	47,073		103,155
Fair Value, Measurements, Recurring | Municipal debt securities | Fair Value, Inputs, Level 2 | Long-term investments
Investment Securities			2,689
Fair Value, Measurements, Recurring | Corporate debt securities | Short-term investments
Investment Securities	80,957		103,961
Fair Value, Measurements, Recurring | Corporate debt securities | Long-term investments
Investment Securities	27,425		30,704
Fair Value, Measurements, Recurring | Corporate debt securities | Fair Value, Inputs, Level 1 | Short-term investments
Investment Securities	0		0
Fair Value, Measurements, Recurring | Corporate debt securities | Fair Value, Inputs, Level 1 | Long-term investments
Investment Securities	0		0
Fair Value, Measurements, Recurring | Corporate debt securities | Fair Value, Inputs, Level 2 | Short-term investments
Investment Securities	80,957		103,961
Fair Value, Measurements, Recurring | Corporate debt securities | Fair Value, Inputs, Level 2 | Long-term investments
Investment Securities	27,425		30,704
Fair Value, Measurements, Recurring | Certificates of deposit | Short-term investments
Investment Securities			10,051
Fair Value, Measurements, Recurring | Certificates of deposit | Fair Value, Inputs, Level 1 | Short-term investments
Investment Securities			0
Fair Value, Measurements, Recurring | Certificates of deposit | Fair Value, Inputs, Level 2 | Short-term investments
Investment Securities			10,051
Fair Value, Measurements, Recurring | Derivative Financial Instruments, Assets | Long-term investments
Investment Securities		$ 2,480	1,858
Fair Value, Measurements, Recurring | Derivative Financial Instruments, Assets | Fair Value, Inputs, Level 1 | Long-term investments
Investment Securities	0		0
Fair Value, Measurements, Recurring | Derivative Financial Instruments, Assets | Fair Value, Inputs, Level 2 | Long-term investments
Investment Securities	2,480		$ 1,858
Fair Value, Measurements, Recurring | Cash Equivalents
Cash Equivalents	9,961
Fair Value, Measurements, Recurring | Cash Equivalents | Fair Value, Inputs, Level 1
Cash Equivalents	781
Fair Value, Measurements, Recurring | Cash Equivalents | Fair Value, Inputs, Level 2
Cash Equivalents	9,180
Fair Value, Measurements, Recurring | Cash Equivalents | Money market funds
Cash Equivalents	781
Fair Value, Measurements, Recurring | Cash Equivalents | Money market funds | Fair Value, Inputs, Level 1
Cash Equivalents	781
Fair Value, Measurements, Recurring | Cash Equivalents | Money market funds | Fair Value, Inputs, Level 2
Cash Equivalents	0
Fair Value, Measurements, Recurring | Cash Equivalents | Commercial paper
Cash Equivalents	8,426
Fair Value, Measurements, Recurring | Cash Equivalents | Commercial paper | Fair Value, Inputs, Level 1
Cash Equivalents	0
Fair Value, Measurements, Recurring | Cash Equivalents | Commercial paper | Fair Value, Inputs, Level 2
Cash Equivalents	8,426
Fair Value, Measurements, Recurring | Cash Equivalents | Municipal debt securities
Cash Equivalents	754
Fair Value, Measurements, Recurring | Cash Equivalents | Municipal debt securities | Fair Value, Inputs, Level 1
Cash Equivalents	0
Fair Value, Measurements, Recurring | Cash Equivalents | Municipal debt securities | Fair Value, Inputs, Level 2
Cash Equivalents	$ 754

Fair Value Measurements Fair Va

Fair Value Measurements Fair Value Measurements Estimated Fair Value of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Secured Long-term Debt, Noncurrent	$ 641,678	$ 588,794
Notes Payable	646,179	593,099
Publicly Held Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes Payable	300,000	300,000
Non-Publicly Held Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes Payable	346,179	293,099
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Fair Value	626,571	575,365
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Publicly Held Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Secured Long-term Debt, Noncurrent	299,250	304,875
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Non-Publicly Held Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Secured Long-term Debt, Noncurrent	$ 327,321	$ 270,490

Fair Value Measurements Aircraf

Fair Value Measurements Aircraft (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Aircraft [Abstract]
Asset Impairment Charges	$ 0	$ 43,280	$ 0

Derivative Instruments (Details

Derivative Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Derivative Instruments Disclosure [Abstract]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	$ 874	$ 1,171	$ 0
Derivative, Gain (Loss) on Derivative, Net	1,292
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	690
Derivative, Notional Amount	$ 2,500	$ 1,900

Income Taxes Income Taxes (Deta

Income Taxes Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Tax Credit Carryforward [Line Items]
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	$ 0	$ 300
Operating Income (Loss)	0	3,126	$ 1,900
Deferred income taxes	0	6,271
Income Tax Reconciliation, Income Tax Expense (Benefit), at Federal Statutory Income Tax Rate	120,847	48,007	51,362
Current Federal Tax Expense (Benefit)	108,119	53,156	52,732
Income taxes, net of refunds	111,399	55,501	53,220
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	3,865	3,442	1,689
Current State and Local Tax Expense (Benefit)	6,501	4,645	4,114
Current Income Tax Expense (Benefit)	115,616	58,655	56,846
Deferred Federal Income Tax Expense (Benefit)	9,458	(8,557)	(1,811)
Deferred State and Local Income Tax Expense (Benefit)	125	(247)	(134)
DeferredTotalIncomeTaxExpenseBenefit	10,773	(7,827)	(1,945)
PROVISION FOR INCOME TAXES	126,389	50,828	54,901
Income Tax Reconciliation, State and Local Income Taxes	4,293	2,587	2,654
Income Tax Reconciliation, Other Reconciling Items	$ 1,249	$ 234	$ 885

Income Taxes The Major Componen

Income Taxes The Major Components of the Company's Net Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Valuation Allowance
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 0	$ (1,330)
Deferred Tax Assets, Net of Valuation Allowance	22,936	13,883
Deferred Tax Liabilities, Net, Noncurrent	(45,580)	(42,872)
Accrued Vacation
Valuation Allowance
Deferred Tax Assets, Gross	1,339	1,149
Deferred Tax Assets, Accrued Bonus
Valuation Allowance
Deferred Tax Assets, Gross	8,189	4,633
State Taxes
Valuation Allowance
Deferred Tax Assets, Gross	2,396	1,484
Accrued Property Taxes
Valuation Allowance
Deferred Tax Assets, Gross	1,149	1,329
Other 1
Valuation Allowance
Deferred Tax Assets, Gross	6,940	2,619
Stock Based Compensation
Valuation Allowance
Deferred Tax Assets, Gross	2,923	2,936
Valuation Allowance, Operating Loss Carryforwards
Valuation Allowance
Deferred Tax Assets, Gross	0	1,063
Prepaid Expenses
Valuation Allowance
Deferred Tax Liabilities, Gross, Noncurrent	5,314	5,482
Depreciation
Valuation Allowance
Deferred Tax Liabilities, Gross, Noncurrent	60,979	44,116
Foreign deferred
Valuation Allowance
Deferred Tax Liabilities, Gross, Noncurrent	2,223	909
Total Noncurrent
Valuation Allowance
Deferred Tax Liabilities, Net	68,516	50,507
Total
Valuation Allowance
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	$ (45,580)	$ (36,624)

Income Taxes The Components of

Income Taxes The Components of the Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
The Components of the Provision (Benefit) for Income Taxes [Abstract]
Current Federal Tax Expense (Benefit)	$ 108,119	$ 53,156	$ 52,732
Current State and Local Tax Expense (Benefit)	6,501	4,645	4,114
Current Foreign Tax Expense (Benefit)	996	854	0
Current Income Tax Expense (Benefit)	115,616	58,655	56,846
Deferred Federal Income Tax Expense (Benefit)	9,458	(8,557)	(1,811)
Deferred State and Local Income Tax Expense (Benefit)	125	(247)	(134)
Deferred Foreign Income Tax Expense (Benefit)	1,190	977	0
DeferredTotalIncomeTaxExpenseBenefit	10,773	(7,827)	(1,945)
PROVISION FOR INCOME TAXES	$ 126,389	$ 50,828	$ 54,901

Income Taxes Reconciliation of

Income Taxes Reconciliation of the Statutory Income Tax Rate and the Company's Effective Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of the Statutory Income Tax Rate and the Company's Effective Tax Rate [Abstract]
Income Tax Reconciliation, Income Tax Expense (Benefit), at Federal Statutory Income Tax Rate	$ 120,847	$ 48,007	$ 51,362
Income Tax Reconciliation, State and Local Income Taxes	4,293	2,587	2,654
Income Tax Reconciliation, Other Reconciling Items	1,249	234	885
PROVISION FOR INCOME TAXES	$ 126,389	$ 50,828	$ 54,901

Income Taxes Components of inco

Income Taxes Components of income/(loss) before income tax expense/(benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Domestic	$ 331,813	$ 129,553	$ 146,680
Income (Loss) from Continuing Operations before Income Taxes, Foreign	14,906	7,578	0
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	$ 346,719	$ 137,131	$ 146,680

Income Taxes Tax Credit Carryfo

Income Taxes Tax Credit Carryforwards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Deferred Tax Assets, Capital Loss Carryforwards	$ 1,300
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	0	$ (1,330)
Deferred Tax Assets, Net of Valuation Allowance	22,936	13,883
Accrued Vacation
Deferred Tax Assets, Gross	1,339	1,149
Deferred Tax Assets, Accrued Bonus [Member]
Deferred Tax Assets, Gross	8,189	4,633
State Taxes
Deferred Tax Assets, Gross	2,396	1,484
Accrued Property Taxes
Deferred Tax Assets, Gross	1,149	1,329
Other 1
Deferred Tax Assets, Gross	6,940	2,619
Stock Based Compensation
Deferred Tax Assets, Gross	2,923	2,936
Valuation Allowance, Operating Loss Carryforwards
Deferred Tax Assets, Gross	0	1,063
Prepaid Expenses
Deferred Tax Liabilities, Gross, Noncurrent	5,314	5,482
Depreciation
Deferred Tax Liabilities, Gross, Noncurrent	60,979	44,116
Foreign deferred
Deferred Tax Liabilities, Gross, Noncurrent	2,223	909
Total Noncurrent
Deferred Tax Liabilities, Net	68,516	50,507
Total
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	$ 45,580	$ 36,624

Related Party Transactions (Det

Related Party Transactions (Details) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2014USD ($)$ / sharesshares	Dec. 31, 2015USD ($)ft²shares	Dec. 31, 2014USD ($)shares	Dec. 31, 2013shares	Dec. 31, 2012shares
Related Party Transaction [Line Items]
Related Party, Ownership Percentage		25.00%
Related Party Transaction, Amounts of Transaction		$ 1,183	$ 3,148
Board Approved Spending		$ 3,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number | shares		82,957	98,782	145,232	128,029
Chief Executive Officer
Related Party Transaction [Line Items]
Total Stock Repurchased, Shares | shares	200,000
Accelerated Share Repurchases, Final Price Paid Per Share | $ / shares	$ 126.20
Total Stock Repurchased, Value	$ 25,240
Chief Operating Officer
Related Party Transaction [Line Items]
Accelerated Share Repurchases, Final Price Paid Per Share | $ / shares	$ 124.05
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number | shares	23,623
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options | shares	127,512
Chief Operating Officer | Minimum
Related Party Transaction [Line Items]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price | $ / shares	$ 36.97
Chief Operating Officer | Maximum
Related Party Transaction [Line Items]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price | $ / shares	$ 108.59
Lease Termination
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction		$ 1,300
Separation payment | Chief Operating Officer
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction	$ 8,500
Game Plane, LLC
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction		365	$ 2,813
Affiliated Entity
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction		2,900	$ 800
GMS Racing, LLC
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction		$ 2,500
Building 2
Related Party Transaction [Line Items]
Area of Real Estate Property | ft²		10,000
Building 1
Related Party Transaction [Line Items]
Area of Real Estate Property | ft²		70,000

Employee Benefit Plans (Details

Employee Benefit Plans (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)$ / sharesshares	Dec. 31, 2014USD ($)$ / sharesshares	Dec. 31, 2013USD ($)$ / sharesshares	Sep. 30, 2014shares	Dec. 31, 2012$ / sharesshares	Dec. 31, 2006shares
Fair Value Inputs, Assets, Quantitative Information [Line Items]
FairValueSARsLiability | $	$ 4,900
Defined Contribution Plan, Maximum Annual Contribution Per Employee, Percent	5.00%
Defined Contribution Plan, Cost Recognized | $	$ 4,218	$ 3,412	$ 2,879
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized						3,000,000
Share-based compensation expense | $	10,474	$ 16,723	$ 9,818
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized | $	6,760
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options | $	340
Cash-settled SARs | $	3,685
EmployeeServiceShareBasedCompensationNonvestedAwardTotalCompensationCostNotYetRecognized | $	$ 10,785
EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostsNotYetRecognizedPeriodForRecognition	1 year 6 months 26 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate	30.18%	29.30%	30.49%
Fair Value Assumptions, Expected Dividend Rate		1.80%	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		50,630	108,041
ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsSARsOutstandingNumber	48,781	88,749	283,631		228,690
ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsSARsOutstandingWeightedAverageExercisePrice | $ / shares	86.65	69.43	49.48		36.89
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	(3,000)	(7,600)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period	3.50	20.42
Exercised (in Shares)	(36,968)	(237,912)	(53,100)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price | $ / shares	$ 52.06	$ 38.39	$ 38.03
SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsSARsOutstandingWeightedAverageRemainingContractualTerm2	2 years 7 months 13 days	3 years 3 months 15 days	3 years 4 months 17 days
ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsSARsOutstandingIntrinsicValue | $	$ 3,960	$ 7,180	$ 14,507
Share Based Compensation Arrangement By Share Based Payment Award SARs Grant In Period Wighted Average Exercise Price | $ / shares		$ 108.59	$ 81.77
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	39,710
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price | $ / shares	$ 81.71
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term	2 years 6 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value | $	$ 3,245
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	19,250
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price | $ / shares	$ 58.11
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term	1 year 11 months 23 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value | $	$ 1,119
ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsSARsExercisesInPeriodTotalIntrinsicValue | $	5,750	$ 9,405	$ 3,261
Proceeds from the exercise of stock options | $	$ 1,924	$ 2,240	$ 2,083
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	82,957	98,782	145,232		128,029
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares	$ 155.30	$ 91.15	$ 62.61		$ 52.63
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares	$ 178.68	$ 109.66	$ 84.36
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	47,810	54,731	85,196
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(54,825)	(90,567)	(64,426)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value | $ / shares	$ 83.35	$ 75.31	$ 52.57
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(8,810)	(10,614)	(3,567)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value | $ / shares	$ 130.35	$ 79.36	$ 82.87
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value | $	$ 4,570	$ 6,820	$ 3,387
Restricted Stock
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition	1 year 8 months 9 days
Stock Appreciation Rights (SARs)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition	1 year 4 months 17 days
Stock Options
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition	1 year 1 month 17 days
3/25/11 Grant | Stock Appreciation Rights (SARs)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Outstanding at Beginning of Period		23,893
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsOutstandingWeightedAverageExercisePrice. | $ / shares		$ 19.01
StockIssuedDuringPeriodSharesSARsExercise	(10,108)
Exercises (in Dollars per share) | $ / shares	$ 19.01
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsForfeituresInPeriod	0
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsForfeituresInPeriodWeightedAverageExercisePrice | $ / shares	$ 0
ShareBasedCompensationArrangementByShareBasedPaymentSARsOutstandingNumberEndOfPeriod	13,785
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsOutstandingWeightedAverageExercisePriceEndOfYear | $ / shares	$ 19.01
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsExercisableNumber	13,785
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsExercisableWeightedAverageExercisePrice | $ / shares	$ 19.01
3/8/13 Grant | Stock Appreciation Rights (SARs)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Outstanding at Beginning of Period		46,545
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsOutstandingWeightedAverageExercisePrice. | $ / shares		$ 20.92
StockIssuedDuringPeriodSharesSARsExercise	(24,283)
Exercises (in Dollars per share) | $ / shares	$ 20.92
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsForfeituresInPeriod	(4,554)
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsForfeituresInPeriodWeightedAverageExercisePrice | $ / shares	$ 20.92
ShareBasedCompensationArrangementByShareBasedPaymentSARsOutstandingNumberEndOfPeriod	17,708
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsOutstandingWeightedAverageExercisePriceEndOfYear | $ / shares	$ 20.92
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsExercisableNumber	3,035
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsExercisableWeightedAverageExercisePrice | $ / shares	$ 20.92
3/6/14 Grant | Stock Appreciation Rights (SARs)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Outstanding at Beginning of Period		49,075
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsOutstandingWeightedAverageExercisePrice. | $ / shares		$ 25.68
StockIssuedDuringPeriodSharesSARsExercise	(9,055)
Exercises (in Dollars per share) | $ / shares	$ 25.68
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsForfeituresInPeriod	(7,790)
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsForfeituresInPeriodWeightedAverageExercisePrice | $ / shares	$ 25.68
ShareBasedCompensationArrangementByShareBasedPaymentSARsOutstandingNumberEndOfPeriod	32,230
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsOutstandingWeightedAverageExercisePriceEndOfYear | $ / shares	$ 25.68
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsExercisableNumber	7,302
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsExercisableWeightedAverageExercisePrice | $ / shares	$ 25.68
2/25/15 Grant | Stock Appreciation Rights (SARs)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award SARs Grant In Period Wighted Average Exercise Price | $ / shares	$ 34.53
Outstanding at Beginning of Period		0
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsOutstandingWeightedAverageExercisePrice. | $ / shares		$ 0
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsForfeituresInPeriod	(9,378)
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsForfeituresInPeriodWeightedAverageExercisePrice | $ / shares	$ 34.53
ShareBasedCompensationArrangementByShareBasedPaymentSARsOutstandingNumberEndOfPeriod	68,018
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsOutstandingWeightedAverageExercisePriceEndOfYear | $ / shares	$ 34.53
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsExercisableNumber	0
ShareBasedCompensationArrangementByShareBasedPaymentAwardSARsExercisableWeightedAverageExercisePrice | $ / shares	$ 0
Share Based Compensation Arrangement by Share Based Payment Award SARs Grant in Period	77,396
Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Assumptions, Expected Dividend Rate	0.49%
Fair Value Assumptions, Risk Free Interest Rate	0.30%	0.40%	0.30%
Minimum | Stock Appreciation Rights (SARs)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Assumptions, Expected Term	3 months 18 days	1 year 4 months 24 days	3 months 18 days
Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Assumptions, Expected Dividend Rate	2.22%
Fair Value Assumptions, Risk Free Interest Rate	1.20%	0.90%	0.50%
Maximum | Stock Appreciation Rights (SARs)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value Assumptions, Expected Term	2 years 6 months	2 years 6 months	2 years 6 months
Chief Operating Officer
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				127,512
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number				23,623

Employee Benefit Plans Employee

Employee Benefit Plans Employee Stock Purchase Plan (Details) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Postemployment Benefits [Abstract]
Shares Held in Employee Stock Option Plan, Allocated		1,000,000
Stock Issued During Period, Shares, Employee Stock Purchase Plans	8,306

Commitments and Contingencies (

Commitments and Contingencies (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)aircraft	Dec. 31, 2014aircraft
Airbus A320 Aircraft Series
Long-term Purchase Commitment [Line Items]
Aircraft scheduled to be acquired	3
Aircraft acquired	6
Airbus A320 Aircraft Series | Capital Addition Purchase Commitments
Long-term Purchase Commitment [Line Items]
Number Of Aircraft Committed To Purchase	8	9
Purchase agreements - 2015
Long-term Purchase Commitment [Line Items]
Purchase Commitment, Remaining Minimum Amount Committed | $	$ 129,100
Purchase Agreements - 2014
Long-term Purchase Commitment [Line Items]
Purchase Commitment, Remaining Minimum Amount Committed | $	$ 39,400

Subsequent Events (Details)

Subsequent Events (Details) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2016USD ($)aircraft	Dec. 31, 2015USD ($)$ / shares	Dec. 31, 2014USD ($)$ / shares	Dec. 31, 2013USD ($)$ / shares
Subsequent Event [Line Items]
Debt Instrument, Collateral		$ 121,000	$ 385,300	$ 106,000
Cash dividends (per Share) | $ / shares		$ 2.75	$ 2.50	$ 2.25
Secured Long-term Debt, Noncurrent		$ 641,678	$ 588,794
Capital Addition Purchase Commitments | Airbus A319 | Subsequent Event
Subsequent Event [Line Items]
Number Of Aircraft Committed To Purchase | aircraft	2
Due January 2021 | Subsequent Event
Subsequent Event [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.75%
Due January 2021 | Airbus A319 | Subsequent Event
Subsequent Event [Line Items]
Debt Instrument, Collateral	$ 28,000