SkyWest (SKYW) 10-K 16 Feb 23 2022 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2022	Feb. 10, 2023	Jun. 30, 2022
Document and Entity Information
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Document Transition Report	false
Entity File Number	0-14719
Entity Registrant Name	SKYWEST INC
Entity Incorporation, State or Country Code	UT
Entity Tax Identification Number	87-0292166
Entity Address, Address Line One	444 South River Road
Entity Address, City or Town	St. George
Entity Address, State or Province	UT
Entity Address, Postal Zip Code	84790
City Area Code	435
Local Phone Number	634-3000
Title of 12(b) Security	Common Stock, No Par Value
Trading Symbol	SKYW
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 1,073,588,080
Entity Common Stock, Shares Outstanding		50,441,238
Auditor Name	Ernst & Young LLP
Auditor Firm ID	42
Auditor Location	Salt Lake City, Utah
Entity Central Index Key	0000793733
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Amendment Flag	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
CURRENT ASSETS:
Cash and cash equivalents	$ 102,984	$ 258,421
Marketable securities	944,231	601,989
Receivables, net	100,523	65,348
Inventories, net	123,209	104,093
Other current assets	100,334	38,742
Total current assets	1,371,281	1,068,593
PROPERTY AND EQUIPMENT:
Aircraft and rotable spares	8,143,614	7,848,100
Deposits on aircraft	23,931	124,964
Buildings and ground equipment	265,019	256,595
Total property and equipment, gross	8,432,564	8,229,659
Less-accumulated depreciation and amortization	(2,884,084)	(2,731,060)
Total property and equipment, net	5,548,480	5,498,599
OTHER ASSETS:
Operating lease right-of-use assets	151,928	238,516
Long-term receivables and other assets	342,864	320,239
Total other assets	494,792	558,755
Total assets	7,414,553	7,125,947
CURRENT LIABILITIES:
Current maturities of long-term debt	438,502	391,798
Accounts payable	422,001	496,333
Accrued salaries, wages and benefits	186,285	150,583
Current maturities of operating lease liabilities	71,726	78,886
Taxes other than income taxes	20,480	28,869
Other current liabilities	33,549	48,152
Total current liabilities	1,172,543	1,194,621
LONG-TERM DEBT, net of current maturities	2,941,772	2,717,420
DEFERRED INCOME TAXES PAYABLE	687,060	663,236
NONCURRENT OPERATING LEASE LIABILITIES	88,622	158,274
OTHER LONG-TERM LIABILITIES	176,925	124,882
COMMITMENTS AND CONTINGENCIES (Note 7)
STOCKHOLDERS' EQUITY:
Preferred stock, 5,000,000 shares authorized; none issued
Common stock, no par value, 120,000,000 shares authorized; 82,592,830 and 82,335,970 shares issued as of December 31, 2022, and December 31, 2021, respectively	734,426	722,310
Retained earnings	2,236,869	2,163,916
Treasury stock, at cost, 31,994,416 and 31,956,047 shares as of December 31, 2022, and December 31, 2021, respectively	(619,862)	(618,712)
Accumulated other comprehensive loss	(3,802)
Total stockholders' equity	2,347,631	2,267,514
Total liabilities and stockholders' equity	$ 7,414,553	$ 7,125,947

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2022	Dec. 31, 2021
CONSOLIDATED BALANCE SHEETS
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	82,592,830	82,335,970
Treasury stock, at cost, shares	31,994,416	31,956,047

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
OPERATING REVENUES:
Total operating revenues	$ 3,004,925	$ 2,713,491	$ 2,127,106
OPERATING EXPENSES:
Salaries, wages and benefits	1,211,551	986,664	826,109
Aircraft maintenance, materials and repairs	644,157	817,803	618,989
Depreciation and amortization	394,552	440,198	474,959
Aircraft fuel	108,456	107,057	61,739
Aircraft rentals	75,353	63,357	65,316
Airport-related expenses	71,549	104,690	93,886
Special items		84,592
Payroll support grant		(422,669)	(345,491)
Other operating expenses	318,145	255,932	222,797
Total operating expenses	2,823,763	2,437,624	2,018,304
OPERATING INCOME	181,162	275,867	108,802
OTHER INCOME (EXPENSE):
Interest income	17,605	1,114	5,879
Interest expense	(127,083)	(123,122)	(123,173)
Other income (expense), net	20,899	(3,249)	1,165
Total other expense, net	(88,579)	(125,257)	(116,129)
INCOME (LOSS) BEFORE INCOME TAXES	92,583	150,610	(7,327)
PROVISION FOR INCOME TAXES	19,630	38,700	1,188
NET INCOME (LOSS)	$ 72,953	$ 111,910	$ (8,515)
BASIC EARNINGS PER SHARE (in dollars per share)	$ 1.44	$ 2.22	$ (0.17)
DILUTED EARNINGS PER SHARE (in dollars per share)	$ 1.44	$ 2.20	$ (0.17)
Weighted average common shares:
Basic (in shares)	50,548	50,348	50,195
Diluted (in shares)	50,644	50,753	50,195
COMPREHENSIVE INCOME (LOSS):
Net income (loss)	$ 72,953	$ 111,910	$ (8,515)
Net unrealized depreciation on marketable securities, net of taxes	(3,802)
TOTAL COMPREHENSIVE INCOME (LOSS)	69,151	111,910	(8,515)
Flying agreements
OPERATING REVENUES:
Total operating revenues	2,899,837	2,615,076	2,060,801
Lease, airport services and other
OPERATING REVENUES:
Total operating revenues	$ 105,088	$ 98,415	$ 66,305

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock Cumulative Effect, Period of Adoption, as Adjusted	Common Stock	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings Cumulative Effect, Period of Adoption, as Adjusted	Retained Earnings	Treasury Stock Cumulative Effect, Period of Adoption, as Adjusted	Treasury Stock	Accumulated Other Comprehensive Loss	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, as Adjusted	Total
Increase (Decrease) in Stockholders' Equity
Change in accounting principle and other			$ (11,639)						$ (11,639)
Balance at Dec. 31, 2019	$ 686,806	$ 686,806		$ 2,067,540	$ 2,079,179	$ (590,971)	$ (590,971)			$ 2,163,375	$ 2,175,014
Balance (in shares) at Dec. 31, 2019	81,743,000	81,743,000				(31,420,000)	(31,420,000)
Increase (Decrease) in Stockholders' Equity
Net income (loss)					(8,515)						(8,515)
Exercise of common stock options and vested employee stock awards		$ 38									$ 38
Exercise of common stock options and vested employee stock awards (in shares)		287,000									2,578
Employee income tax paid on vested equity awards							$ (6,165)				$ (6,165)
Employee income tax paid on vested equity awards (in shares)							(108,000)
Sale of common stock under employee stock purchase plan		$ 2,781									2,781
Sale of common stock under employee stock purchase plan (in shares)		65,000
Stock based compensation expense		$ 6,802									6,802
Treasury stock purchases							$ (20,000)				(20,000)
Treasury stock purchases (in shares)							(386,000)
Cash dividends declared					(7,019)						(7,019)
Warrants issued to U.S. Treasury		8,248									8,248
Balance at Dec. 31, 2020		$ 704,675			2,052,006		$ (617,136)				2,139,545
Balance (in shares) at Dec. 31, 2020		82,095,000					(31,914,000)
Increase (Decrease) in Stockholders' Equity
Net income (loss)					111,910						111,910
Exercise of common stock options and vested employee stock awards		$ 606									$ 606
Exercise of common stock options and vested employee stock awards (in shares)		177,000									41,020
Employee income tax paid on vested equity awards							$ (1,576)				$ (1,576)
Employee income tax paid on vested equity awards (in shares)							(42,000)
Sale of common stock under employee stock purchase plan		$ 2,540									2,540
Sale of common stock under employee stock purchase plan (in shares)		64,000
Stock based compensation expense		$ 8,685									8,685
Warrants issued to U.S. Treasury		5,804									5,804
Balance at Dec. 31, 2021		$ 722,310			2,163,916		$ (618,712)				2,267,514
Balance (in shares) at Dec. 31, 2021		82,336,000					(31,956,000)
Increase (Decrease) in Stockholders' Equity
Net income (loss)					72,953						72,953
Exercise of common stock options and vested employee stock awards		$ 142									$ 142
Exercise of common stock options and vested employee stock awards (in shares)		151,000									9,817
Employee income tax paid on vested equity awards							$ (1,150)				$ (1,150)
Employee income tax paid on vested equity awards (in shares)							(38,000)
Sale of common stock under employee stock purchase plan		$ 2,815									2,815
Sale of common stock under employee stock purchase plan (in shares)		106,000
Stock based compensation expense		$ 9,159									9,159
Net unrealized depreciation on marketable securities, net of tax								$ (3,802)			(3,802)
Balance at Dec. 31, 2022		$ 734,426			$ 2,236,869		$ (619,862)	$ (3,802)			$ 2,347,631
Balance (in shares) at Dec. 31, 2022		82,593,000					(31,994,000)

CONSOLIDATED STATEMENTS OF ST_2

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2020
CONSOLIDATED STATEMENTS OF STOCKHOLDERS EQUITY
Net unrealized depreciation on marketable securities, tax	$ 1,224
Cash dividends declared (in dollars per share)		$ 0.14

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 72,953	$ 111,910	$ (8,515)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	394,552	440,198	474,959
Stock based compensation expense	9,159	8,685	6,802
Write-off of maintenance assets			3,255
Increase (decrease) in credit loss reserves	(4,591)	(4,249)	17,087
Loss (gain) on disposal of fixed assets	(7,948)	(4,586)	445
Gain on investments in other companies	(11,380)
Net increase in deferred income taxes	23,825	37,305	6,100
Impairment on assets held for sale	51,384
Special items		84,592
Changes in operating assets and liabilities:
Decrease (increase) in receivables	(32,959)	(30,093)	26,831
Decrease (increase) in income tax receivable	7,815	(5,570)	7,225
Decrease (increase) in inventories	(16,628)	(12,897)	19,307
Decrease (increase) in other current assets	(2,871)	(1,936)	8,233
Decrease in operating lease right-of-use assets	86,588	43,846	53,647
Decrease in operating lease liabilities	(76,812)	(51,326)	(65,557)
Increase (decrease) in deferred revenue	40,812	(6,832)	110,728
Increase in unbilled revenue	(11,491)	(8,404)
Increase (decrease) in accounts payable and other current liabilities	(42,032)	231,177	(26,984)
NET CASH PROVIDED BY OPERATING ACTIVITIES	480,376	831,820	633,563
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of marketable securities	(1,834,403)	(1,517,861)	(1,347,775)
Sales of marketable securities	1,488,359	1,526,057	1,170,556
Acquisition of property and equipment:
Aircraft and rotable spare parts	(632,460)	(537,574)	(425,618)
Buildings and ground equipment	(13,031)	(18,127)	(12,678)
Proceeds from the sale of property and equipment	16,983	7,117	3,239
Deposits on aircraft	(37,100)	(125,701)	(9,625)
Aircraft deposits applied towards acquired aircraft	138,383	32,962	27,858
Increase in other assets	(31,625)	(65,395)	(89,428)
NET CASH USED IN INVESTING ACTIVITIES	(904,894)	(698,522)	(683,471)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of long-term debt	684,502	450,032	406,364
Principal payments on long-term debt	(415,050)	(540,537)	(187,404)
Payment of debt issuance cost	(2,178)	(1,665)	(4,130)
Net proceeds from issuance of common stock	2,957	3,146	2,819
Employee income tax paid on vested equity awards	(1,150)	(1,576)	(6,165)
Purchase of treasury stock			(20,000)
Payment of cash dividends			(13,059)
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	269,081	(90,600)	178,425
Increase (decrease) in cash and cash equivalents	(155,437)	42,698	128,517
Cash and cash equivalents at beginning of period	258,421	215,723	87,206
CASH AND CASH EQUIVALENTS AT END OF PERIOD	102,984	258,421	215,723
Non-cash investing and financing activities:
Acquisition of property and equipment	16,826	11,336	22,187
Warrants issued to U.S. Treasury		5,804	8,248
Cash paid during the period for:
Interest, net of capitalized amounts	125,321	124,918	125,440
Income taxes	$ 1,166	$ 6,589	$ 1,780

Nature of Operations and Summar

Nature of Operations and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2022
Condensed Consolidated Financial Statements
Nature of Operations and Summary of Significant Accounting Policies	(1) Nature of Operations and Summary of Significant Accounting Policies SkyWest, Inc. (the “Company”), through its subsidiary, SkyWest Airlines, Inc. (“SkyWest Airlines”) operates the largest regional airline in the United States. As of December 31, 2022, SkyWest Airlines offered scheduled passenger service under code-share agreements with United Airlines, Inc. (“United”), Delta Air Lines, Inc. (“Delta”), American Airlines, Inc. (“American”) and Alaska Airlines, Inc. (“Alaska”) with approximately 1,620 total daily departures to destinations in the United States, Canada and Mexico. Additionally, the Company provides airport customer service and ground handling services for other airlines throughout its system. As of December 31, 2022, the Company had 625 total aircraft in its fleet, including 517 aircraft in scheduled service or under contract under its code-share agreements, summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ E175 CRJ900 CRJ700 CRJ200 Total United 90 ​ — ​ 19 ​ 111 ​ 220 Delta ​ 84 ​ 41 ​ 5 ​ 25 ​ 155 American 20 ​ — ​ 80 ​ — ​ 100 Alaska 42 ​ — ​ — ​ — ​ 42 Aircraft in scheduled service or under contract ​ 236 ​ 41 ​ 104 ​ 136 ​ 517 Leased to third parties — ​ 5 ​ 35 ​ — ​ 40 Other* — ​ 3 ​ 28 ​ 37 ​ 68 Total Fleet 236 ​ 49 ​ 167 ​ 173 ​ 625 *As of December 31, 2022, other aircraft included: supplemental spare aircraft supporting the Company’s code-share agreements that may be used in future code-share or leasing arrangements, aircraft transitioning between code-share agreements with the Company’s major airline partners, aircraft held for sale or aircraft that are scheduled to be disassembled for use as spare parts. For the year ended December 31, 2022, approximately 42.6% of the Company’s aircraft in scheduled service was operated for United, approximately 30.0% was operated for Delta, approximately 19.3% was operated for American and approximately 8.1% was operated for Alaska. SkyWest Airlines has been a code-share partner with Delta since 1987, United since 1997, Alaska since 2011 and American since 2012. As of December 31, 2022, SkyWest Airlines operated as a Delta Connection carrier primarily in Salt Lake City, Detroit and Minneapolis, a United Express carrier primarily in Los Angeles, San Francisco, Denver, Houston, Chicago and the Pacific Northwest, an American carrier primarily in Chicago, Dallas, Los Angeles and Phoenix and an Alaska carrier primarily in the Pacific Northwest. SkyWest Airlines operates the following aircraft manufactured by Bombardier: CRJ900s, CRJ700s and CRJ200s, and E175s manufactured by Embraer. The CRJ700, CRJ900 E175 have seat Basis of Presentation The Company’s consolidated financial statements include the accounts of the Company and the SkyWest Airlines and SkyWest Leasing segments, with all inter-company transactions and balances having been eliminated. In preparing the accompanying consolidated financial statements, the Company has reviewed, as determined necessary by the Company’s management, events that have occurred after December 31, 2022, through the filing date of the Company’s annual report with the U.S. Securities and Exchange Commission. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States (“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 and the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates and assumptions. Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. The Company had no restricted cash as of December 31, 2022 and 2021. Marketable Securities The Company’s investments in debt securities are classified as available-for-sale and are reported at fair market value with the net unrealized depreciation reported as a component of accumulated other comprehensive income (loss) in stockholders’ equity. At the time of sale, any realized appreciation or depreciation, calculated by the specific identification method, is recognized in other income and expense. The Company’s position in marketable securities as of December 31, 2022 and 2021 was as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross unrealized ​ Gross unrealized ​ ​ ​ ​ At December 31, 2022 Amortized Cost holding gains holding losses Fair market value Marketable securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Bond and bond funds ​ $ 629,280 ​ $ — ​ $ (5,026) ​ $ 624,254 ​ Commercial Paper ​ 319,977 ​ — ​ — ​ 319,977 ​ Total marketable securities ​ $ 949,257 ​ $ — ​ $ (5,026) ​ $ 944,231 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross unrealized ​ ​ Gross unrealized ​ ​ ​ ​ At December 31, 2021 Amortized Cost holding gains holding losses Fair market value Marketable securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Bond and bond funds ​ $ 54,673 ​ $ — ​ $ — ​ $ 54,673 ​ Commercial Paper ​ 547,316 ​ — ​ — ​ 547,316 ​ Total marketable securities ​ $ 601,989 ​ $ — ​ $ — ​ $ 601,989 ​ ​ Inventories Inventories include expendable parts, fuel and supplies and are valued at cost (FIFO basis) less an allowance for obsolescence based on historical results, excess parts and management’s expectations of future operations. Expendable inventory parts are charged to expense as used. An obsolescence allowance for flight equipment expendable parts is accrued based on estimated lives of the corresponding fleet types and salvage values. The inventory allowance as of December 31, 2022 and 2021, was $24.2 million and $23.0 million, respectively. Property and Equipment Property and equipment are stated at cost and depreciated over their useful lives to their estimated residual values using the straight-line method as follows: ​ ​ ​ ​ ​ Assets ​ Depreciable Life ​ Current Residual Value Aircraft, rotable spares, and spare engines ​ up to 22 years up to 20 % Ground equipment ​ up to 10 years 0 % Office equipment ​ up to 7 years ​ 0 % Leasehold improvements ​ Shorter of 15 years or lease term 0 % Buildings ​ 20 - 39.5 years 0 % ​ Impairment of Long-Lived Assets As of December 31, 2022, the Company had approximately $5.5 billion of property and equipment, net. In accounting for these long-lived assets, the Company makes estimates about the expected useful lives of the assets, the expected residual values of certain of these assets, and the potential for impairment based on the fair value of the assets and the cash flows they generate. Factors indicating potential impairment include, but are not limited to, significant decreases in the market value of the long-lived assets, a significant change in the condition of the long-lived assets and operating cash flow losses associated with the use of the long-lived assets. On a periodic basis, the Company evaluates whether impairment indicators are present. When considering whether or not impairment of long- lived assets exists, the Company groups similar assets together at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities and compare the undiscounted cash flows for each asset group to the net carrying amount of the assets supporting the asset group. Asset groupings are done at the aircraft type level. During 2022, the Company committed to a plan to sell 14 CRJ700 aircraft, resulting in an impairment on the assets held for sale of $51.4 million. See Note 9, “Assets Held for Sale” for more information on the assets held for sale. During 2021, the Company recorded an impairment charge of $84.6 million to write-down certain CRJ900 aircraft to their estimated fair value. See Note 10, “Special Items” for more information on the CRJ900 impairment. Capitalized Interest Interest is capitalized on aircraft purchase deposits as a portion of the cost of the asset and is depreciated over the estimated useful life of the asset. During the years ended December 31, 2022 and 2021, the Company capitalized interest costs of approximately $1.9 million, and during the year ended December 31, 2020, the Company capitalized interest costs of approximately $1.7 million. Maintenance The Company operates under a U.S. Federal Aviation Administration approved continuous inspection and maintenance program. The Company uses the direct expense method of accounting for its regional jet engine overhauls. The Company has engine services agreements with third-party vendors to provide long-term engine services covering the scheduled and unscheduled repairs for most of its aircraft. Under the terms of the agreements, the Company pays a fixed dollar amount per engine hour flown on a monthly basis and the third-party vendors will assume the responsibility to repair the engines at no additional cost to the Company, subject to certain specified exclusions. Maintenance costs under these contracts are recognized when the engine hour is flown pursuant to the terms of each contract. The costs of maintenance for airframe and avionics components, landing gear and other recurring maintenance are expensed as incurred. In 2020, the Company wrote-off $3.7 million of long-lived maintenance assets at maintenance locations the Company vacated during the year as a maintenance expense. There was not a similar expense in 2022 and 2021. Flying Agreements and Airport Customer Service and Other Revenues The Company recognizes revenue under its flying agreements and under its lease, airport services and other service agreements when the service is provided under the applicable agreement. Under the Company’s capacity purchase agreements with United, Delta, American and Alaska (each, a “major airline partner”), the major airline partner generally pays the Company a fixed-fee for each departure, flight hour (measured from takeoff to landing, excluding taxi time) or block hour (measured from takeoff to landing, including taxi time) incurred, and an amount per aircraft in service each month with additional incentives based on flight completion and on-time performance. The major airline partner also directly pays for or reimburses the Company for certain direct expenses incurred under the capacity purchase agreement, such as fuel, airport landing fees and airport rents. Under the capacity purchase agreements, the Company’s performance obligation is met when each flight is completed, measured in completed block hours, and is reflected in flying agreements revenue. The transaction price for the capacity purchase agreements is determined from the fixed-fee consideration, incentive consideration and directly reimbursed expenses earned as flights are completed over the agreement term. For the years ended December 31, 2022, 2021 and 2020, capacity purchase arrangements represented approximately 88.0%, 84.3% and 87.0% of the Company’s flying agreements revenue, respectively. Under the Company’s prorate arrangements (also referred to as a “prorate” or “revenue-sharing” agreement), the major airline partner and the Company negotiate a passenger fare proration formula, pursuant to which the Company receives a percentage of the ticket revenues for those passengers traveling for one portion of their trip on a Company airline and the other portion of their trip on the major airline partner. Under the Company’s prorate flying agreements, the performance obligation is met and revenue is recognized when each flight is completed based upon the portion of the prorate passenger fare the Company determines that it will receive for each completed flight. The transaction price for the prorate agreements is determined from the proration formula derived from each passenger ticket amount on each completed flight over the agreement term. For the years ended December 31, 2022, 2021 and 2020, prorate flying agreements represented approximately 12.0%, 15.7%, and 13.0% of the Company’s flying agreements revenue, respectively. The following table represents the Company’s flying agreements revenue by type for the years ended December 31, 2022, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended December 31, ​ 2022 2021 ​ 2020 Capacity purchase agreements flight operations revenue (non-lease component) ​ $ 2,028,308 ​ ​ 1,678,219 ​ ​ 1,265,923 Capacity purchase agreements fixed aircraft lease revenue ​ ​ 504,529 ​ ​ 527,173 ​ ​ 526,018 Capacity purchase agreements variable aircraft lease revenue ​ 17,664 ​ ​ — ​ ​ — Prorate agreements revenue ​ 349,336 ​ ​ 409,684 ​ ​ 268,860 Flying agreements revenue ​ $ 2,899,837 $ 2,615,076 ​ $ 2,060,801 ​ The Company allocates the total consideration received under its capacity purchase agreements between the lease and non-lease components based on stand-alone selling prices. A portion of the Company’s compensation under its capacity purchase agreements is designed to reimburse the Company for certain aircraft ownership costs. The consideration for aircraft ownership costs varies by agreement but is intended to cover either the Company’s aircraft principal and interest debt service costs, its aircraft depreciation and interest expense or its aircraft lease expense costs while the aircraft is under contract. The consideration received for the use of the aircraft under the Company’s capacity purchase agreements is accounted for as lease revenue, inasmuch as the agreements identify the “right of use” of a specific type and number of aircraft over a stated period of time. The lease revenue associated with the Company’s capacity purchase agreements is accounted for as an operating lease and is reflected as flying agreements revenue on the Company’s consolidated statements of comprehensive income (loss). During the year ended December 31, 2022, the Company amended its capacity purchase agreements with certain major airline partners that reduced certain contractual fixed monthly payments and increased certain contractual variable payments. Accordingly, the Company re-evaluated the allocation of the total consideration between the lease and non-lease components for the amended agreements, including the allocation of the consideration to the fixed and variable lease components. As a result of these amendments, the Company deferred recognizing lease revenue on $22.1 million of the allocated fixed monthly lease payments received during the year ended December 31, 2022, under the straight-line method. The Company has not separately stated aircraft rental income and aircraft rental expense in the consolidated statement of comprehensive income (loss) because the use of the aircraft is not a separate activity of the total service provided under the capacity purchase agreements. A portion of the Company’s compensation under its capacity purchase agreements relates to operating the aircraft, identified as the non-lease component of the capacity purchase agreement. The Company recognizes revenue attributed to the non-lease component received as fixed-fees for each departure, flight hour or block hour on an as-completed basis for each reporting period. The Company recognizes revenue attributed to the non-lease component received as fixed monthly payments per aircraft proportionate to the number of block hours completed during each reporting period, relative to the estimated number of block hours the Company anticipates completing over the remaining contract term. Due to the lower number of block hours completed during 2020 as a result of the COVID-19 pandemic compared to historical levels, the amount of cash collected for the fixed amount per aircraft for operating the aircraft did not align with revenue recognized based on block hours completed. Accordingly, the Company deferred recognizing revenue on fixed monthly payments the Company received for operating the aircraft under its capacity purchase agreements beginning in 2020. In 2022, the Company deferred $18.7 million of fixed monthly payments under certain agreements and recognized $11.5 million of unbilled revenue under certain other agreements, compared to recognizing previously deferred revenue of $6.8 million and $8.4 million of unbilled revenue in 2021. The Company’s total deferred revenue balance, as of December 31, 2022, was $144.7 million, including $5.2 million in other current liabilities and $139.5 million in other long-term liabilities. The Company’s unbilled revenue balance as of December 31, 2022, was $19.9 million, including $9.9 million in other current assets and $10.0 million in other long-term assets. The Company’s deferred revenue balance as of December 31, 2021, was $103.9 million, including $24.5 million in other current liabilities and $79.4 million in other long-term liabilities. The Company’s unbilled revenue balance as of December 31, 2021, of $8.4 million was included in other long-term assets. In the event a flying agreement includes a mid-term rate reset to adjust rates prospectively and the contractual rates under the Company’s flying agreements have not been finalized at quarterly or annual financial statement dates, the Company applies the variable constraint guidance under Topic 606, where the Company records revenue to the extent it believes that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. In several of the Company’s agreements, the Company is eligible to receive incentive compensation upon the achievement of certain performance criteria. The incentives are defined in the agreements and are measured and determined on a monthly, quarterly or semi-annual basis. At the end of each period during the term of an agreement, the Company calculates the incentives achieved during that period and recognizes revenue attributable to that agreement accordingly, subject to the variable constraint guidance under Topic 606. The following summarizes the significant provisions of each code-share agreement the Company has with each major airline partner through SkyWest Airlines: United Express Agreements Agreement Aircraft type Number of Aircraft Term / Termination Dates United Express Agreements (capacity purchase agreement) ​ · E175 · CRJ 700 · CRJ 200 ​ 90 19 70 ​ · Individual aircraft have scheduled removal dates under the agreement between 2024 and 2029 · The average remaining term of the aircraft under contract is 3.5 years United Express Prorate Agreement (prorate agreement) ​ · CRJ 200 ​ 41* ​ · Terminable with 120 Total under United Express Agreements ​ ​ ​ 220 ​ ​ ​ Delta Connection Agreements Agreement Aircraft type Number of Aircraft Term / Termination Dates Delta Connection Agreement (capacity purchase agreement) ​ · E175 · CRJ 900 · CRJ 700 ​ 84 41 5 ​ · Individual aircraft have scheduled removal dates from 2023 to 2033 · The average remaining term of the aircraft under contract is 5.6 years Delta Connection Prorate Agreement (prorate agreement) ​ · CRJ 200 ​ 25* ​ · Terminable with 30 Total under Delta Connection Agreements ​ ​ ​ 155 ​ ​ ​ American Capacity Purchase Agreement Agreement Aircraft type Number of Aircraft Term / Termination Dates American Agreement (capacity purchase agreement) ​ · E175 · CRJ 700 ​ 20 80 ​ · Individual aircraft have scheduled removal dates from 2023 to 2032 · The average remaining term of the aircraft under contract is 4.3 years Total under American Agreement ​ ​ ​ 100 ​ ​ ​ Alaska Capacity Purchase Agreement Agreement Aircraft type Number of Aircraft Term / Termination Dates Alaska Agreement (capacity purchase agreement) ​ · E175 ​ 42 ​ · Individual aircraft have scheduled removal dates from 2030 to 2034 · The average remaining term of the aircraft under contract is 8.8 years ​ * The Company’s prorate agreements are based on specific routes, not a specific aircraft count. The number of aircraft listed above for each prorate agreement approximates the number of aircraft the Company uses to serve the prorate routes. In addition to the contractual arrangements described above, as of December 31, 2022, SkyWest Airlines has a capacity purchase agreement with Delta to place a total of three additional E175 aircraft into service, with delivery dates currently scheduled in 2023 and 2024. SkyWest Airlines has a capacity purchase agreement with Alaska to place one additional E175 aircraft into service with a delivery date currently scheduled for 2025. Final delivery and in-service dates for aircraft to be placed under contract may be adjusted based on various factors. When an aircraft is scheduled to be removed from a capacity purchase arrangement, the Company may, as practical under the circumstances, negotiate an extension with the respective major airline partner, negotiate the placement of the aircraft with another major airline partner, return the aircraft to the lessor if the aircraft is leased and the lease is expiring, place owned aircraft for sale, or pursue other uses for the aircraft. Other uses for the aircraft may include placing the aircraft in a prorate agreement, leasing the aircraft to a third party or parting out the aircraft to use the engines and parts as spare inventory or to lease the engines to a third party. Lease, airport services and other revenues primarily consists of revenue generated from aircraft and spare engines leased to third parties and airport customer services, such as gate and ramp agent services at applicable airports where the Company has agreements with third parties. The following table represents the Company’s lease, airport services and other revenues for the years ended December 31, 2022, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended December 31, ​ 2022 2021 ​ 2020 Operating lease revenue relating to lease payments ​ $ 48,714 ​ $ 46,532 ​ $ 34,791 Operating lease revenue relating to variable lease payments ​ ​ 17,050 ​ ​ 19,998 ​ ​ 5,710 Airport customer service and other revenue ​ ​ 39,324 ​ ​ 31,885 ​ ​ 25,804 Lease, airport services and other ​ $ 105,088 ​ $ 98,415 ​ $ 66,305 ​ ​ ​ ​ 2023 $ 45,900 2024 ​ 45,177 2025 ​ 40,207 2026 ​ 34,640 2027 ​ 34,619 Thereafter ​ 86,182 ​ ​ $ 286,725 Of the Company’s $5.5 billion of property and equipment, net as of December 31, 2022, $221.0 million of regional jet aircraft and spare engines were leased to third parties under operating leases. The Company’s mitigation strategy for the residual asset risks of these assets includes leasing aircraft and engine types that can be operated by the Company in the event of a default. Additionally, the operating leases typically have specified lease return condition requirements paid by the lessee to the Company and the Company typically maintains inspection rights under the leases. The transaction price for airport customer service agreements is determined from an agreed-upon rate by location applied to the applicable number of flights handled by the Company over the agreement term. The Company’s operating revenues could be impacted by several factors, including changes to the Company’s code-share agreements with its major airline partners, changes in flight schedules, contract modifications resulting from contract renegotiations, the Company’s ability to earn incentive payments contemplated under the Company’s code-share agreements and settlement of reimbursement disputes with the Company’s major airline partners. Other ancillary revenues commonly associated with airlines, such as baggage fee revenue, ticket change fee revenue and the marketing component of the sale of mileage credits, are retained by the Company’s major airline partners on flights that the Company operates under its code-share agreements. As of December 31, 2022, the Company had $100.5 million in accounts receivable of which $73.7 million related to flying agreements. As of December 31, 2021, the Company had $65.3 million in accounts receivable of which $50.8 million related to flying agreements. Allowance for Credit Losses The Company adopted on January 1, 2020. At adoption, the Company’s primary financial assets included trade receivables from its flying agreements, a note receivable from the sale of the Company’s subsidiary, ExpressJet Airlines, Inc., in 2019, and receivables from aircraft manufacturers and other third parties in the airline industry. The Company recorded a credit loss of $11.6 million net of income tax in conjunction with the adoption of Topic 326. The Company recorded this credit loss as a January 1, 2020, beginning balance sheet entry to retained earnings (net of income tax). The Company monitors publicly available credit ratings for entities for which the Company has a significant receivable balance. As of December 31, 2022, the Company had gross receivables of $122.5 million in current assets and gross receivables of $210.5 million in other long-term assets. The Company has established credit loss reserves based on publicly available historic default rates issued by a third party for companies with similar credit ratings, factoring in the term of the respective accounts receivable or note receivable. During the year ended December 31, 2022, there were no significant changes in the outstanding accounts receivable or notes receivable or the credit ratings of the entities. The following table summarizes the changes in allowance for credit losses: ​ ​ ​ ​ ​ ​ Allowance for Credit Losses Balance at January 1, 2020 ​ ​ 15,388 Adjustments to credit loss reserves ​ ​ 30,837 Write-offs charged against allowance ​ ​ — Balance at December 31, 2020 ​ $ 46,225 Adjustments to credit loss reserves ​ ​ (4,249) Write-offs charged against allowance ​ ​ — Balance at December 31, 2021 ​ $ 41,976 Adjustments to credit loss reserves ​ (4,591) Write-offs charged against allowance ​ — Balance at December 31, 2022 ​ $ 37,385 ​ Income Taxes The Company recognizes a net liability or asset for the deferred tax consequences of all temporary differences between the tax basis of assets and liabilities and their reported amounts in the consolidated financial statements that are expected to result in taxable or deductible amounts in future years when the reported amounts of the assets and liabilities are recovered or settled. Net Income (Loss) Per Common Share Basic net income (loss) per common share (“Basic EPS”) excludes dilution and is computed by dividing net income (loss) by the weighted average number of common shares outstanding during the period. Diluted net income per common share (“Diluted EPS”) reflects the potential dilution that could occur if stock options or other contracts to issue common stock were exercised or converted into common stock. The computation of Diluted EPS does not assume exercise or conversion of securities that would have an anti-dilutive effect on net income (loss) per common share. Securities that could potentially dilute Basic EPS in the future, and which were excluded from the calculation of Diluted EPS because inclusion of such share would be anti-dilutive, are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 PSP1 and Treasury Loan Warrants (1) ​ ​ 437 ​ ​ — ​ ​ 582 PSP2 Warrants (2) ​ ​ 125 ​ ​ — ​ ​ — PSP3 Warrants (3) ​ ​ 78 ​ ​ 78 ​ ​ — Employee Stock Awards ​ ​ 219 ​ ​ — ​ ​ 314 Total antidilutive securities ​ ​ 859 ​ ​ 78 ​ ​ 896 (1) Pursuant to the payroll support program established under the CARES Act (“PSP1”) and Loan and Guarantee Agreement with the U.S. Department of the Treasury (“U.S. Treasury”), SkyWest issued to Treasury warrants to purchase shares of SkyWest common stock for an exercise price of $28.38 per share. (2) Pursuant to the payroll support program established under the 2021 Consolidated Appropriations Act (“PSP2”), SkyWest issued to U.S. Treasury warrants to purchase shares of SkyWest common stock for an exercise price of $40.41 per share. (3) Pursuant to the payroll support program established under the American Rescue Plan (“PSP3”), SkyWest issued to U.S. Treasury warrants to purchase shares of SkyWest common stock for an exercise price of $57.47 per share. Additionally, for the years ended December 31, 2022, 2021 and 2020, 146,000, 140,000 and 178,000 performance share units (at target performance) were excluded from the computation of Diluted EPS since the Company had not achieved the minimum target thresholds as of December 31, 2022, 2021 and 2020, respectively. The calculation of the weighted average number of common shares outstanding for Basic EPS and Diluted EPS are as follows for the years ended December 31, 2022, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Numerator: ​ ​ ​ ​ Net income (loss) ​ $ 72,953 ​ $ 111,910 ​ $ (8,515) Denominator: ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings per share weighted average shares ​ 50,548 ​ 50,348 ​ 50,195 Dilution due to employee equity awards and warrants ​ 96 ​ 405 ​ — Diluted earnings per share weighted average shares ​ 50,644 ​ 50,753 ​ 50,195 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings (loss) per share ​ $ 1.44 ​ $ 2.22 ​ $ (0.17) Diluted earnings (loss) per share ​ $ 1.44 ​ $ 2.20 ​ $ (0.17) ​ Comprehensive Income (Loss) Comprehensive income (loss) includes charges and credits to stockholders’ equity that are not the result of transactions with the Company’s shareholders, including changes in unrealized appreciation (or depreciation) on marketable debt securities. Fair Value of Financial Instruments The carrying amounts reported in the consolidated balance sheets for receivables and accounts payable approximate fair values because of the immediate or short-term maturity of these financial instruments. Marketable securities are reported at fair value based on market quoted prices in the consolidated balance sheets. If quoted prices in active markets are no longer available, the Company has estimated the fair values of these securities utilizing a discounted cash flow analysis. These analyses consider, among other items, the collateralization underlying the security investments, the creditworthiness of the counterparty, the timing of expected future cash flows, and the expectation of the next time the security is expected to have a successful auction. Certain investments in other companies are reported at fair value based on market quoted prices or using the Black Scholes Option Pricing model in the consolidated balance sheets. The fair value of the Company’s long-term debt is estimated based on current rates offered to the Company for similar debt. Segment Reporting GAAP requires disclosures related to components of a company for which separate financial information is available to, and regularly evaluated by, the Company’s chief operating decision maker when deciding how to allocate resources and in assessing performance. The Company has two reportable segments: SkyWest Airlines and SkyWest Leasing. Information pertaining to the Company’s reportable segments is presented in Note 3, Segment Reporting

Recovery from the COVID-19 Pand

Recovery from the COVID-19 Pandemic and Labor Impact	12 Months Ended
	Dec. 31, 2022
Recovery from the COVID-19 Pandemic and Labor Impact
Recovery from the COVID-19 Pandemic and Labor Impact	(2) Recovery from the COVID-19 Pandemic and Labor Impact COVID-19 had a significant, negative impact on the Company’s business and financial results in 2020 with moderate improvement in 2021. During 2022, passenger demand recovered; however, indirect factors of COVID-19, such as employee attrition, particularly captain attrition, and workforce shortages negatively impacted the Company’s operations in 2022. Payroll Support Programs. under the CARES Act, the PSP2 under the 2021 Appropriations Act and the PSP3 under The relief payments were conditioned on the Company’s agreement to, among other things, refrain from conducting involuntary employee layoffs or furloughs through September 30, 2021. Other conditions included restrictions on share repurchases and dividends through September 30, 2022, continuing essential air service as directed by the U.S. Department of Transportation and certain limitations on executive compensation. programs included an amount in the form of a payroll grant and an amount in the form of an unsecured 10-year loan. In return, the Company issued to Treasury warrants to purchase shares of the Company’s common stock. The Company recorded the payroll grant proceeds as an offset to operating expenses in the period the funds were intended to compensate. The PSP1 grant was recognized during 2020 and grants received from PSP2 and PSP3 were recognized during 2021. No grants were received or recognized during 2022. In 2020, in connection with the CARES Act, the Company entered into the Treasury Loan Agreement with Treasury (“Secured Loan”) and borrowed $60.0 million under the agreement and in conjunction therewith, issued warrants to purchase shares of the Company’s common stock. During 2021, the Company repaid all amounts outstanding under the secured loan with Treasury, and in connection with The following table summarizes the amounts received and warrants issued under the payroll support programs and secured loan facility (in thousands except warrant amounts): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ Grant Loan ​ Number of Warrants PSP1 ​ $ 450,701 ​ $ 345,491 ​ $ 105,210 ​ 370,720 Secured Loan ​ ​ 60,000 ​ ​ — ​ ​ 60,000 ​ 211,416 PSP2 ​ ​ 268,070 ​ ​ 217,649 ​ ​ 50,421 ​ 124,773 PSP3 ​ 250,029 ​ 205,020 ​ 45,009 ​ 78,317 Total ​ $ 1,028,800 ​ $ 768,160 ​ $ 260,640 ​ 785,226 ​ See Note 11, “Capital Transactions” for further discussion on the warrants issued to acquire the Company’s shares issued to Treasury.

Segment Reporting

Segment Reporting	12 Months Ended
	Dec. 31, 2022
Segment Reporting
Segment Reporting	(3) Segment Reporting GAAP requires disclosures related to components of a company for which separate financial information is available to, and regularly evaluated by, the Company’s chief operating decision maker when deciding how to allocate resources and in assessing performance. The Company’s two reportable segments consist of the operations of SkyWest Airlines and SkyWest Leasing activities. The Company’s chief operating decision maker analyzes the profitability of operating new aircraft financed through the issuance of debt, including the Company’s E175 fleet, separately from the profitability of the Company’s capital deployed for ownership and financing of such aircraft. The SkyWest Airlines segment includes revenue earned under the applicable capacity purchase agreements attributed to operating such aircraft and the respective operating costs. The SkyWest Leasing segment includes applicable revenue earned under the applicable capacity purchase agreements attributed to the ownership of new aircraft acquired through the issuance of debt and the respective depreciation and interest expense of such aircraft. The SkyWest Leasing segment also includes the activity of leasing regional jet aircraft and spare engines to third parties and other activities. The SkyWest Leasing segment’s total assets and capital expenditures include new aircraft acquired through the issuance of debt and assets leased to third parties. The following represents the Company’s segment data for the years ended December 31, 2022, 2021, and 2020 (in thousands). ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2022 ​ ​ SkyWest ​ SkyWest ​ ​ ​ Airlines Leasing Consolidated Operating revenues (1) ​ $ 2,492,318 ​ $ 512,607 ​ $ 3,004,925 Operating expense ​ 2,525,076 ​ 298,687 ​ 2,823,763 Depreciation and amortization expense ​ 182,475 ​ 212,077 ​ 394,552 Interest expense ​ 12,805 ​ 114,278 ​ 127,083 Segment profit (loss) (2) ​ (45,563) ​ 99,642 ​ 54,079 Total assets (as of December 31, 2022) ​ 2,977,804 ​ 4,436,749 ​ 7,414,553 Capital expenditures (including non-cash) ​ 82,891 ​ 579,426 ​ 662,317 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2021 ​ ​ SkyWest ​ SkyWest ​ ​ ​ Airlines Leasing Consolidated Operating revenues (1) ​ $ 2,192,432 ​ $ 521,059 ​ $ 2,713,491 Operating expense ​ 2,177,524 ​ 260,100 ​ 2,437,624 Depreciation and amortization expense ​ 210,281 ​ 229,917 ​ 440,198 Special items - impairment charges ​ ​ 84,592 ​ ​ — ​ ​ 84,592 Interest expense ​ 13,360 ​ 109,762 ​ 123,122 Segment profit (2) ​ 1,548 ​ 151,197 ​ 152,745 Total assets (as of December 31, 2021) ​ 2,957,745 ​ ​ 4,168,202 ​ 7,125,947 Capital expenditures (including non-cash) ​ 128,712 ​ ​ 438,325 ​ 567,037 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2020 ​ ​ SkyWest ​ SkyWest ​ ​ ​ Airlines Leasing Consolidated Operating revenues (1) ​ $ 1,636,762 ​ $ 490,344 ​ $ 2,127,106 Operating expense ​ 1,716,808 ​ 301,496 ​ 2,018,304 Depreciation and amortization expense ​ 221,216 ​ 253,743 ​ 474,959 Interest expense ​ 12,381 ​ 110,792 ​ 123,173 Segment profit (loss) (2) ​ (92,427) ​ 78,056 ​ (14,371) Total assets (as of December 31, 2020) ​ 2,804,259 ​ ​ 4,083,363 ​ 6,887,622 Capital expenditures (including non-cash) ​ 124,825 ​ ​ 335,658 ​ 460,483 (1) Prorate revenue and airport customer service revenue are primarily reflected in the SkyWest Airlines segment. (2) Segment profit (loss) is equal to operating income less interest expense.

Long-term Debt

Long-term Debt	12 Months Ended
	Dec. 31, 2022
Long-term Debt
Long-term Debt	(4) Long-term Debt Long-term debt consisted of the following as of December 31, 2022 and 2021 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, December 31, ​ ​ 2022 ​ 2021 Notes payable to banks, due in quarterly installments, plus interest at 2.33% to 5.95% through 2034, secured by aircraft ​ $ 2,604,058 ​ $ 2,535,827 ​ Notes payable to banks, due in monthly or semi-annual installments, plus interest at 2.68% to 5.66% through 2032, secured by aircraft and engines ​ 604,613 ​ 404,471 ​ Notes payable to U.S. Government, interest due quarterly at 1.00% through 2025 and based on SOFR plus spread from 2025 through 2031, unsecured ​ 200,640 ​ 200,640 ​ Long-term debt ​ $ 3,409,311 ​ $ 3,140,938 ​ Current portion of long-term debt ​ (442,360) ​ (395,371) ​ Less long-term portion of unamortized debt issue cost, net ​ ​ (25,179) ​ ​ (28,147) ​ Long-term debt, net of current maturities and debt issue costs ​ $ 2,941,772 ​ $ 2,717,420 ​ ​ ​ ​ ​ ​ ​ ​ ​ Current portion of long-term debt ​ 442,360 ​ 395,371 ​ Less current portion of unamortized debt issue cost, net ​ ​ (3,858) ​ ​ (3,573) ​ Current portion of long-term debt, net of debt issue costs ​ $ 438,502 ​ $ 391,798 ​ ​ During 2022, the Company took delivery of 25 new E175 aircraft that the Company financed through $516.6 million of long-term debt. The debt associated with the 25 E175 aircraft has 5- to 12-year terms, is due in monthly or quarterly installments, and is secured by the E175 aircraft. During 2022, the Company executed promissory notes for $167.9 million. The promissory notes have three As of December 31, 2022 and 2021, the Company had $3.05 billion and $2.94 billion, respectively, of long-term debt obligations primarily related to the acquisition of aircraft and certain spare engines. The average effective interest rate on the debt related to those long-term debt obligations at December 31, 2022 and 2021, was approximately 4.0% and 3.8%, respectively. The aggregate amounts of principal maturities of long-term debt as of December 31, 2022 were as follows (in thousands): ​ ​ ​ ​ ​ 2023 $ 442,360 2024 ​ 443,642 ​ 2025 ​ 527,564 ​ 2026 ​ 504,269 ​ 2027 ​ 457,326 ​ Thereafter ​ 1,034,150 ​ ​ ​ $ 3,409,311 ​ ​ As of December 31, 2022, SkyWest Airlines had a $100 million line of credit. As of December 31, 2021, SkyWest Airlines had a $75 million line of credit. The line of credit includes minimum liquidity and profitability covenants and is secured by certain assets. As of December 31, 2022 and 2021, SkyWest Airlines had no amounts outstanding under the line of credit facility. However, at December 31, 2022 and 2021, the Company had $29.9 million and $31.4 million, respectively, in letters of credit issued under the facility which reduced the amount available under the facility to $70.1 million and $43.6 million, respectively. The line of credit expires March 25, 2025 and has a variable interest rate of 3.5% plus the one month SOFR rate. As of December 31, 2022 and 2021, the Company had $59.2 million and $61.4 million, respectively, in letters of credit and surety bonds outstanding with various banks and surety institutions. The Company’s debt agreements are not traded on an active market and are recorded at carrying value on the Company’s consolidated balance sheet. The fair value of the Company’s long-term debt is estimated based on current rates offered to the Company for similar debt. Debt is primarily classified as Level 2 within the fair value hierarchy. The carrying value and fair value of the Company’s long-term debt as of December 31, 2022 and 2021, were as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 ​ December 31, 2021 Carrying value ​ $ 3,409,311 ​ $ 3,140,938 Fair value ​ $ 3,264,704 ​ $ 3,132,072 ​

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2022
Income Taxes
Income Taxes	(5) Income Taxes The provision for income taxes includes the following components (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Current tax provision (benefit): ​ ​ ​ ​ Federal ​ $ (7,319) ​ $ — ​ $ (4,397) ​ State ​ 1,813 ​ 846 ​ (875) ​ ​ ​ (5,506) ​ 846 ​ (5,272) ​ Deferred tax provision (benefit): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ 21,587 ​ 32,510 ​ 6,659 ​ State ​ 3,549 ​ 5,344 ​ (199) ​ ​ ​ 25,136 ​ 37,854 ​ 6,460 ​ Provision for income taxes ​ $ 19,630 ​ $ 38,700 ​ $ 1,188 ​ ​ The following is a reconciliation between a federal income tax rate of 21% and the effective tax rate which is derived by dividing the provision for income taxes by the income (loss) before the provision for income taxes (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Computed provision (benefit) for income taxes at the statutory rate $ 19,442 $ 31,628 $ (1,539) ​ Increase (decrease) in income taxes resulting from: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ State income tax provision, net of federal income tax benefit ​ 4,295 ​ 6,247 ​ 173 ​ Non-deductible expenses ​ ​ 546 ​ ​ 1,007 ​ ​ 2,539 ​ Valuation allowance changes affecting the provision for income taxes ​ 1,716 ​ — ​ (892) ​ Excess tax benefits from share-based compensation ​ ​ 534 ​ ​ (92) ​ ​ (1,434) ​ Other, net ​ (6,903) ​ (90) ​ 2,341 ​ Provision for income taxes ​ $ 19,630 ​ $ 38,700 ​ $ 1,188 ​ ​ For the year ended December 31, 2022, the Company recorded a $1.7 million valuation allowance against certain deferred tax assets associated with state net operating losses with a limited carry forward period. For the year ended December 31, 2020, the Company released $0.9 million of valuation allowance against certain deferred tax assets primarily associated with state net operating losses with a limited carry forward period. The increase in the valuation allowance for 2022 was primarily based on changes in the Company's income tax projections by jurisdiction which increased the amount of deferred tax assets that are anticipated to expire before the deferred tax assets may be utilized. The Company recorded a $0.5 million expense, $0.1 million benefit and $1.4 million benefit from share-based compensation in 2022, 2021, and 2020, respectively, relating to ASU 2016-09 which, requires excess tax benefits and deficiencies to be recognized in the income tax provision during the period stock options are exercised and when stock awards vest. For the year ended December 31, 2022, the Company recorded a $7.3 million tax benefit for the release of uncertain tax position under ASC Topic 740 which is recorded in “Other, net” above. The significant components of the Company’s net deferred tax assets and liabilities as of December 31, 2022 and 2021, are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2022 ​ 2021 Deferred tax assets: ​ ​ ​ Accrued benefits ​ $ 29,154 ​ $ 21,401 ​ Net operating loss carryforward ​ 186,517 ​ 175,659 ​ Aircraft credits ​ 77,962 ​ 22,265 ​ Deferred revenue ​ ​ 35,385 ​ ​ 25,405 ​ Operating lease liabilities ​ ​ 39,209 ​ ​ 57,991 ​ Interest deduction limitation ​ ​ 26,469 ​ ​ — ​ Accrued reserves and other ​ 49,972 ​ 31,431 ​ Total deferred tax assets ​ 444,668 ​ 334,152 ​ Valuation allowance ​ (1,716) ​ — ​ Deferred tax liabilities: ​ ​ ​ ​ ​ ​ ​ Accelerated depreciation ​ (1,094,538) ​ (940,867) ​ Operating lease right-of-use assets ​ ​ (35,474) ​ ​ (56,521) ​ Total deferred tax liabilities ​ (1,130,012) ​ (997,388) ​ Net deferred tax liability ​ $ (687,060) ​ $ (663,236) ​ ​ At , respectively. The Company anticipates that the federal and state net operating losses will start to expire in 2037 and 2023, respectively. The Company has no ongoing federal examinations. The Company has one ongoing state examination for tax year 2020. Federal tax years 2019, 2020 and 2021 are open to examination. Under Accounting Standard Codification (“ASC”) : ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Unrecognized tax benefits at the beginning of year $ 15,529 $ 14,980 $ 14,620 Gross increases - current year tax positions ​ ​ — ​ ​ — ​ ​ — Gross increases - prior year tax positions ​ 343 ​ 549 ​ 360 Gross decreases - prior year tax positions ​ ​ (7,662) ​ ​ — ​ ​ — Unrecognized tax benefits at end of year ​ $ 8,210 ​ $ 15,529 ​ $ 14,980 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest and penalties in year-end balance ​ $ 607 ​ $ 976 ​ $ 427 ​ For the years ended December 31, 2022, 2021, and 2020, the Company recorded $343,000, $549,000, and $360,000, respectively, of interest expense related to uncertain tax positions not offset by the Company's tax attributes. For the year ended December 31, 2022, the Company released $7.7 million of the prior year uncertain tax position, including interest, as the tax year statutes impacted by these positions have closed.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies
Commitments and Contingencies	(6) Commitments and Contingencies Self-Insurance The Company self-insures a portion of its potential losses from claims related to workers’ compensation, environmental issues, property damage, medical insurance for employees and general liability. Losses are accrued based on an estimate of the ultimate aggregate liability for claims incurred, using standard industry practices and the Company’s actual experience. The Company uses judgment and estimates in determining the ultimate aggregate liabilities for claims incurred in its workers’ compensation liability. The Company also used assumptions in determining the workers compensation liability such as an estimation of loss payment and loss reporting development patterns. At December 31, 2022 and 2021, the Company’s accrued workers’ compensation liability totaled $21.6 million and $17.5 million, respectively, of which $8.0 million and $7.1 million, respectively, was short-term and included in other current liabilities. Actual results could differ from these estimates. Legal Matters The Company is subject to certain legal actions which it considers routine to its business activities. As of December 31, 2022, management believed, after consultation with legal counsel, that the ultimate outcome of such legal matters was not likely to have a material adverse effect on the Company’s financial position, liquidity or results of operations. Concentration Risk and Significant Customers The Company requires no collateral from its major airline partners or customers, but monitors the financial condition of its major airline partners. Under the majority of the Company’s code-share agreements, the Company receives weekly payments from its major code-share partners that approximate a significant percentage of the compensation earned for such period. Additionally, the Company provides certain customer service functions at multiple airports for various airlines and the Company maintains a credit loss reserve based upon expected collectability of all accounts receivable. For the years ended December 31, 2022, 2021, and 2020, the Company’s contractual relationships with Delta and United combined accounted for approximately 72.5%, 73.5% and 76.4%, respectively of the Company’s total revenues. Employees Under Collective Bargaining Agreements As of December 31, 2022, the Company had approximately 13,582 employees. Although no SkyWest Airlines employees are represented by a national union, the majority of SkyWest Airline employees are covered under by a written, stable and binding collective bargaining agreement under the RLA, entered into between SkyWest Airlines and a long-established labor association, such as the SkyWest Airlines Pilot Association (“SAPA”). Aircraft Purchase Commitments As of December 31, 2022, the Company had a purchase commitment to purchase two new E175 aircraft in 2023, one new E175 aircraft in 2024 and one new E175 aircraft in 2025. Guarantees During the year ended December 31, 2022, the Company agreed to guarantee $19.8 million of debt for a 14 CFR Part 135 air carrier. The debt is secured by the Part 135 air carrier’s aircraft and engines and has a five-year term. The purpose of the arrangement is to increase the potential number of commercial pilots in the Company’s hiring pipeline. In exchange for providing the guarantee, the Company received 6.5% of the guaranteed amount as consideration, payable in common stock of the Part 135 air carrier, and is recorded in “Other income, net” on the Company’s consolidated statements of comprehensive income (loss) over the term of the guarantee. The Company also recorded the estimated credit loss associated with the guarantee in “Other long-term liabilities” on the Company’s consolidated balance sheet based on publicly available historical default rates issued by a third party for companies with similar credit ratings, factoring the collateral and guarantee term.

Leases

Leases	12 Months Ended
	Dec. 31, 2022
Leases
Leases	(7) Leases The Company leases property and equipment under operating leases. For leases with durations longer than 12 months, the Company recorded the related operating lease right-of-use asset and operating lease liability at the present value of lease payments over the term. The Company used its incremental borrowing rate to discount the Aircraft As of December 31, 2022, excluding aircraft financed by the Company’s major airline partners that the Company operates for them under contract, the Company had 43 aircraft under long-term lease agreements with remaining terms ranging from one year to eight years. The Company leases 32 CRJ aircraft under a lease agreement that expires in March 2024. During the year ended December 31, 2022, the Company began storing aircraft under this lease agreement, which shortened the Company’s estimated useful life of the aircraft under the lease and resulted in the Company recognizing $11.4 million of accelerated lease expense during the year ended December 31, 2022. Airport facilities The Company has operating leases for facility space including airport terminals, office space, cargo warehouses and maintenance facilities. The Company generally leases this space from government agencies that control the use of the various airports. The remaining lease terms for facility space vary from one month to 34 years. The Company’s operating leases with lease rates that are variable based on airport operating costs, use of the facilities or other variable factors are excluded from the Company’s right-of-use assets and operating lease liabilities in accordance with accounting guidance. Leases As of December 31, 2022, the Company’s right-of-use assets were $151.9 million, the Company’s current maturities of operating lease liabilities were $71.7 million, and the Company’s noncurrent lease liabilities were $88.6 million. During 2022, the Company paid $77.9 million in operating leases reflected as a reduction from operating cash flows. The table below presents lease related terms and discount rates as of December 31, 2022. ​ ​ ​ ​ As of December 31, 2022 Weighted-average remaining lease term for operating leases 6.5 years Weighted-average discount rate for operating leases 6.1% ​ The Company’s lease costs for 2022 and 2021 included the following components (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended December 31, ​ 2022 2021 Operating lease cost ​ $ 97,998 ​ $ 89,891 Variable and short-term lease cost ​ 1,830 ​ 4,468 Sublease income ​ ​ (7,089) ​ ​ (6,552) Total lease cost ​ $ 92,739 ​ $ 87,807 ​ As of December 31, 2022, the Company leased aircraft, airport facilities, office space, and other property and equipment under non-cancelable operating leases, which are generally on a long-term, triple-net lease basis pursuant to which the Company pays taxes, maintenance, insurance and certain other operating expenses applicable to the leased property. The Company expects that, in the normal course of business, such operating leases that expire will be renewed or replaced by other leases, or the property may be purchased rather than leased. The following table summarizes future minimum rental payments primarily related to leased aircraft and maintenance facilities required under operating leases that had initial or remaining non-cancelable lease terms as of December 31, 2022 (in thousands): ​ ​ ​ ​ ​ 2023 $ 74,557 2024 ​ 32,525 2025 ​ 15,837 2026 ​ 13,427 2027 ​ 12,291 Thereafter ​ 54,298 ​ ​ $ 202,935 ​ Total rental expense for non-cancelable aircraft operating leases was approximately $75.4 million, $63.4 million and $65.3 million for the years ended December 31, 2022, 2021, and 2020, respectively. The minimum rental expense for airport station rents was approximately $13.2 million, $17.2 million and $20.1 million for the years ended December 31, 2022, 2021, and 2020, respectively.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2022
Fair Value Measurements
Fair Value Measurements	(8) Fair Value Measurements The Company holds certain assets that are required to be measured at fair value in accordance with GAAP. The Company determined fair value of these assets based on the following three levels of inputs: ​ Level 1 Level 2 Level 3 ​ As of December 31, 2022 and 2021, the Company held certain assets that are required to be measured at fair value on a recurring basis. Assets measured at fair value on a recurring basis are summarized below (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements as of December 31, 2022 ​ Total Level 1 Level 2 Level 3 Marketable Securities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Bonds and bond funds ​ $ 624,254 ​ $ — ​ $ 624,254 ​ $ — Commercial paper ​ 319,977 ​ — ​ 319,977 ​ — ​ ​ $ 944,231 ​ $ — ​ $ 944,231 ​ $ — Investments in Other Companies ​ ​ 21,380 ​ ​ 7,200 ​ ​ — ​ ​ 14,180 Cash and Cash Equivalents ​ ​ 102,984 ​ ​ 102,984 ​ ​ — ​ ​ — Total Assets Measured at Fair Value ​ $ 1,068,595 ​ $ 110,184 ​ $ 944,231 ​ $ 14,180 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements as of December 31, 2021 ​ ​ Total ​ Level 1 ​ Level 2 ​ Level 3 Marketable Securities ​ ​ ​ ​ Bonds and bond funds ​ $ 54,673 ​ $ — ​ $ 54,673 ​ $ — Commercial paper ​ 547,316 ​ — ​ 547,316 ​ — ​ ​ $ 601,989 ​ $ — ​ $ 601,989 ​ $ — Cash and Cash Equivalents ​ ​ 258,421 ​ ​ 258,421 ​ ​ — ​ ​ — Total Assets Measured at Fair Value ​ $ 860,410 ​ $ 258,421 ​ $ 601,989 ​ $ — ​ The Company’s “Marketable Securities” classified as Level 2 primarily utilize broker quotes in a non-active market for valuation of these securities. See Note 14, “Investments in Other Companies” regarding the Company’s investments in other companies, for the year ended December 31, 2022. The Company did not make any significant transfers of securities between Level 1, Level 2 and Level 3 during the year ended December 31, 2022. The Company’s policy regarding the recording of transfers between levels is to record any such transfers at the end of the reporting period.

Assets Held for Sale

Assets Held for Sale	12 Months Ended
	Dec. 31, 2022
Assets Held for Sale
Assets Held for Sale	(9) Assets Held for Sal e ended December 31, 2022, the Company committed to a formal plan to sell 14 CRJ700 aircraft. The aircraft are expected to be disposed of via sale within the next 12 months. Accordingly, the Company determined the aircraft met the criteria to be classified as assets held for sale. The Company presented the $56.7 million of assets held for sale at the lower of their current carrying value or their fair market value less costs to sell and included the amount in “Other current assets” on the Company’s consolidated balance sheet. The fair values are based upon observable and unobservable inputs, including a third-party valuation, market trends and condition of the airframes and engines, considered Level 3 within the fair value hierarchy. The assumptions used to determine the fair value of the assets held for sale are subject to inherent uncertainty and could produce a wide range of outcomes which the Company will continue to monitor in future periods as new information becomes available. Prior to the ultimate sale of the assets, subsequent changes in the estimate of the fair value of the assets held for sale will be recorded as a gain or loss with a corresponding adjustment to the assets’ carrying value. In connection with the classification of these assets as held for sale, the Company recorded an impairment loss of $51.4 million, which is included in “Other operating expenses” on the Company’s consolidated statements of comprehensive income and in the SkyWest Leasing segment for the year ended December 31, 2022.

Special Items

Special Items	12 Months Ended
	Dec. 31, 2022
Special Items
Special Items	(10) Special Items During 2021, the Company recorded a non-cash impairment charge of $84.6 million to write-down certain CRJ900 aircraft to their estimated fair value. In 2021, the Company evaluated its CRJ900 fleet and related CRJ900 assets for impairment. Pursuant to ASC 360-10, “Impairment and Disposal of Long-Lived Assets,” the Company determined that the asset group for the CRJ900 aircraft existed at the major airline partner level. A recoverability test was performed utilizing estimated undiscounted future cash flows for the CRJ900 aircraft pursuant to applicable capacity purchase agreement terms and forecasted cash flow including the estimated value the Company would realize upon disposal of aircraft. This was compared to the carrying value of the related assets resulting in a cash flow deficiency indicating that an impairment existed. The impairment analysis required the Company to perform an assessment of the fair value of its long-lived assets related to the CRJ900 aircraft within the asset groups utilized in the recoverability test. The Company engaged a third party to assist in determining the fair value of these aircraft. These values were estimated based on listed market values or recent third-party market transactions for similar assets, adjusted by the related maintenance status of the fleet. This special item impairment charge is reflected in the SkyWest Airlines operating expenses under Note 3, “Segment Reporting” for the year ended December 31, 2021.

Capital Transactions

Capital Transactions	12 Months Ended
	Dec. 31, 2022
Capital Transactions
Capital Transactions	(11) Capital Transactions Preferred Stock The Company is authorized to issue 5,000,000 shares of preferred stock in one or more series without shareholder approval. No shares of preferred stock are presently outstanding. The Company’s Board of Directors is authorized, without any further action by the shareholders of the Company, to (i) divide the preferred stock into series; (ii) designate each such series; (iii) fix and determine dividend rights; (iv) determine the price, terms and conditions on which shares of preferred stock may be redeemed; (v) determine the amount payable to holders of preferred stock in the event of voluntary or involuntary liquidation; (vi) determine any sinking fund provisions; and (vii) establish any conversion privileges. Stock Compensation On May 7, 2019, the Company’s shareholders approved the adoption of the SkyWest, Inc. 2019 Long-Term Incentive Plan, which provides for the issuance of up to 4,500,000 shares of common stock to the Company’s directors, employees, consultants and advisors (the “2019 Incentive Plan”). The 2019 Incentive Plan provides for awards in the form of options to acquire shares of common stock, stock appreciation rights, restricted stock grants, restricted stock units and performance awards. The 2019 Incentive Plan is administered by the Compensation Committee of the Company’s Board of Directors (the “Compensation Committee”). As of December 31, 2022, the 2019 Incentive Plan had 2.8 million shares remaining available for future issuance. Stock Options The fair value of stock options awarded under the Company’s stock option plans has been estimated as of the grant date using the Black-Scholes option pricing model. The Company uses historical data to estimate option exercises and employee termination in the option pricing model. The expected term of options granted is derived from the output of the option pricing model and represents the period of time that options granted are expected to be outstanding. The expected volatilities are based on the historical volatility of the Company’s traded stock and other factors. During the years ended December 31, 2022, 2021, and 2020, the Company did not grant any options to purchase shares of common stock to its employees. Options are exercisable for a period as defined by the Compensation Committee on the date granted; however, no stock option will be exercisable before six months have elapsed from the date of grant and no stock option shall be exercisable after seven years from the date of grant. The following table summarizes the stock option activity for all of the Company’s plans for the years ended December 31, 2022, 2021, and 2020. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2022 ​ 2021 ​ 2020 ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Average ​ ​ Aggregate ​ ​ ​ Weighted ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ Remaining ​ ​ Intrinsic ​ ​ ​ Average ​ ​ ​ Average ​ ​ Number of ​ Exercise ​ Contractual ​ ​ Value ​ Number of ​ Exercise ​ Number of ​ Exercise ​ ​ Options ​ Price ​ Term ​ ​ ($000) ​ Options ​ Price ​ Options ​ Price Outstanding at beginning of year 16,633 ​ $ 14.62 1.0 years ​ $ 410.4 57,653 $ 14.74 60,231 $ 14.74 ​ Granted — ​ — ​ ​ ​ ​ ​ ​ — ​ — — ​ — ​ Exercised (9,817) ​ 14.52 ​ ​ ​ ​ ​ ​ (41,020) ​ 14.78 (2,578) ​ 14.78 ​ Cancelled — ​ — ​ ​ ​ ​ ​ ​ — ​ — — ​ — ​ Outstanding at end of year 6,816 ​ $ 14.78 0.1 years ​ $ 11.8 16,633 ​ 14.62 57,653 ​ 14.74 ​ Exercisable at December 31, 2022 6,816 ​ $ 14.78 ​ 0.1 years ​ $ 11.8 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Exercisable at December 31, 2021 16,633 ​ $ 14.62 ​ 1.0 year ​ $ 410.4 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The total intrinsic value of options to acquire shares of the Company’s common stock that were exercised during the years ended December 31, 2022, 2021, and 2020, was $0.1 million, $1.8 million and $0.1 million, respectively. All of the Company’s stock options were vested as of December 31, 2022. The following table summarizes information about the Company’s stock options outstanding at December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ Options Exercisable ​ ​ ​ ​ ​ ​ Weighted Average ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number ​ Remaining ​ Weighted Average ​ Number ​ Weighted Average Range of Exercise Prices ​ Outstanding ​ Contractual Life ​ Exercise Price ​ Exercisable ​ Exercise Price $14.00 to $15.00 6,816 0.1 years ​ 14.78 6,816 ​ 14.78 ​ ​ Restricted Stock Units During the year ended December 31, 2022, the Company granted 66,680 restricted stock units to certain of the Company’s employees under the 2019 Incentive Plan. The restricted stock units granted during the year ended December 31, 2022, have a three-year cliff-vesting period, during which the recipient must remain employed with the Company or its subsidiaries. The weighted average fair value of the restricted stock units at the date of grants made during the year ended December 31, 2022, was $32.86 per share. The following table summarizes the activity of restricted stock units granted to certain Company employees for the years ended December 31, 2022, 2021, and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ ​ Grant-Date Fair ​ ​ Number of RSUs ​ ​ Value Non-vested RSUs outstanding at December 31, 2019 284,686 ​ $ 45.21 ​ Granted 82,505 ​ 61.45 ​ Vested (103,231) ​ 35.81 ​ Cancelled (25,983) ​ 52.31 ​ Non-vested RSUs outstanding at December 31, 2020 237,977 ​ $ 54.15 ​ Granted 44,770 ​ 44.87 ​ Vested (69,184) ​ 53.41 ​ Cancelled (13,390) ​ 52.28 ​ Non-vested RSUs outstanding at December 31, 2021 200,173 ​ $ 52.45 ​ Granted 66,680 ​ 32.86 ​ Vested (86,534) ​ 48.69 ​ Cancelled (20,297) ​ 44.91 ​ Non-vested RSUs outstanding at December 31, 2022 160,022 ​ $ 47.28 ​ ​ Performance Share Units During the year ended December 31, 2022, the Compensation Committee granted performance share units, which are performance-based restricted stock units, to certain Company employees. The PSUs have a three-year vesting period, during which the recipient must remain employed with the Company. The number of performance shares awardable from the 2022 grants can range from 0% to 250% of the original amount granted depending on the Company’s performance over three one-year measurement periods against the pre-established targets. The Company’s compensation expense for performance share units is based upon the projected number of performance share units estimated to be awarded at the conclusion of the performance period. During 2022, the Compensation Committee awarded 40% of the shares related to the performance share grant in 2019 based on the Company’s performance for the three years ended December 31, 2021, measured against the pre-established targets for the same period. This resulted in the forfeiture of 45,695 PSUs in 2022 from target related to the 2019 PSU grant. The Compensation Committee will determine the achievement of performance results and corresponding vesting of performance shares for each year’s grant in 2020, 2021 and 2022 following the conclusion of the respective performance period. At the end of each performance period, the number of shares awarded can range from 0% to 250% of the original granted amount for performance share units granted in 2022 and 2021 and 0% to 200% for performance share units granted in 2020. The following table summarizes the activity of performance share units granted at target as of December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ ​ Grant-Date Fair ​ ​ Number of PSUs ​ ​ Value Non-vested PSUs outstanding at December 31, 2019 233,571 ​ $ 45.44 Granted 69,132 ​ 61.45 Additional PSUs awarded from the 2017 grant ​ 83,042 ​ ​ 35.81 Vested (166,084) ​ 35.81 Cancelled (23,052) ​ 53.66 Non-vested PSUs outstanding at December 31, 2020 196,609 ​ $ 54.17 Granted 157,210 ​ 44.87 PSUs forfeited from the 2018 grant ​ (11,392) ​ ​ 53.41 Vested (45,644) ​ 53.41 Cancelled (3,991) ​ 53.30 Non-vested PSUs outstanding at December 31, 2021 292,792 ​ $ 49.39 Granted 225,345 ​ 32.73 PSUs forfeited from the 2019 grant ​ (45,695) ​ ​ 48.87 Vested (30,480) ​ 48.87 Cancelled (13,032) ​ 41.81 Non-vested PSUs outstanding at December 31, 2022 428,930 ​ $ 40.96 ​ As of December 31, 2022, the Company had $18.5 million of total unrecognized compensation cost related to non-vested restricted stock grants and non-vested performance stock units. Total unrecognized compensation cost will be adjusted for future changes in estimated forfeitures and estimates of the Company’s future performance for unvested performance share units. The Company expects to recognize this cost over a weighted average period of 1.9 years. Taxes The Company’s treatment of stock option grants of non-qualified options, restricted stock units and performance shares results in the creation of a deferred tax asset, which is a temporary difference, until the time that the option is exercised or the restrictions lapse. Warrants During the year ended December 31, 2021, the Company issued to Treasury warrants to purchase 203,090 shares of the Company’s common stock as part of the PSP E The weighted average grant-date fair value of these warrants was estimated at $32.52 and $22.31 per share for the 124,773 and 78,317 warrants, respectively, During the year ended December 31, 2020, the Company issued to Treasury warrants to purchase 370,720 shares of the Company’s common stock as part of the CARES Act payroll support. xercise price of $28.38 per share for a five-year term from the date of issuance. Additionally, in 2020, the Company issued to Treasury warrants to purchase 211,416 shares of the Company’s common stock in conjunction with the Company’s $60 million borrowing under the CARES Act Secured Loan facility. The warrants were issued with an e xercise price of $28.38 per share for a five-year term from the date of issuance. The weighted average grant-date fair value of these warrants issued to Treasury was estimated at $15.22 The Company did not issue any warrants for the year ended December 31, 2022.

Retirement Plans and Employee S

Retirement Plans and Employee Stock Purchase Plans	12 Months Ended
	Dec. 31, 2022
Retirement Plans and Employee Stock Purchase Plans
Retirement Plans and Employee Stock Purchase Plans	(12) Retirement Plans and Employee Stock Purchase Plans SkyWest Retirement Plan The Company sponsors the SkyWest, Inc. Employees’ Retirement Plan (the “SkyWest Plan”). Employees who are at least 18 years of age are eligible for participation in the SkyWest Plan. Employees may elect to make contributions to the SkyWest Plan. Generally, the Company matches 100% of such contributions up to levels ranging from 2% to 12% of compensation, based on position and years of service. SkyWest Airlines pilots with ten or more years of service receive a non-elective contribution of 12% of their compensation in place of a matching contribution. Additionally, a discretionary contribution may be made by the Company. The Company’s combined contributions to the SkyWest Plan were $45.4 million, $42.1 million and $31.9 million for the years ended December 31, 2022, 2021 and 2020, respectively. Employee Stock Purchase Plans In May 2009, the Company’s Board of Directors approved the SkyWest, Inc. 2009 Employee Stock Purchase Plan (the “2009 Stock Purchase Plan”). All employees who have completed 90 days of employment with the Company or one of its subsidiaries are eligible to participate in the 2009 Stock Purchase Plan, except employees who own five percent or more of the Company’s common stock. The 2009 Stock Purchase Plan enables employees to purchase shares of the Company’s common stock at a five percent discount, through payroll deductions. Employees can contribute up to 15% of their base pay, not to exceed $25,000 each calendar year, for the purchase of shares. Shares are purchased semi-annually at a five percent discount based on the end of the period price. Employees can terminate their participation in the 2009 Stock Purchase Plan at any time upon written notice. The following table summarizes purchases made under the 2009 Employee Stock Purchase Plans during the years ended December 31, 2022, 2021 and 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Number of shares purchased ​ 105,606 ​ 63,962 ​ 65,512 ​ Average price of shares purchased ​ $ 26.66 ​ $ 39.70 ​ $ 42.45 ​ ​ The 2009 Stock Purchase Plan is a non-compensatory plan under the accounting guidance. Therefore, no compensation expense was recorded for the years ended December 31, 2022, 2021, and 2020.

Stock Repurchase

Stock Repurchase	12 Months Ended
	Dec. 31, 2022
Stock Repurchase
Stock Repurchase	(13) Stock Repurchase The Company’s Board of Directors has adopted a stock repurchase program which authorizes the Company to repurchase shares of the Company’s common stock in the public market or in private transactions, from time to time, at prevailing prices. The Company’s stock repurchase program authorizes the repurchase of up to $250.0 million of the Company’s common stock commencing on February 5, 2019, of which $139.6 million remained available at December 31, 2022. During the year ended December 31, 2020, the Company repurchased 0.4 million shares of common stock for approximately $20.0 million at a weighted average price per share of $51.87. The Company did not repurchase any shares of its common stock during 2022 and 2021. Under the terms of the Additionally, during the years ended December 31, 2022, 2021 and 2020, the Company paid $1.2 million, $1.6 million and $6.2 million, respectively, for a net settlement of the income tax obligation on employee equity awards that vested during the applicable periods.

Investments in Other Companies

Investments in Other Companies	12 Months Ended
	Dec. 31, 2022
Investments in Other Companies
Investments in Other Companies	(14) Investments in Other Companies Equity Method Investment During 2019, the Company created a joint venture with Regional One, Inc. (“Regional One”) by investing $22.3 million for a 75% ownership interest in Aero Engines, LLC. (“Aero Engines”). The Company invested an additional $1.0 million into Aero Engines in 2020 and $3.3 million during 2022 and retained a 75% ownership interest. The primary purpose of Aero Engines is to lease engines to third parties. Aero Engines requires unanimous approval from the Company and Regional One for its engine purchases, dispositions, lease agreements with third parties and all other material transactions. The Company determined Aero Engines is a variable interest entity as the Company has a 75% ownership interest in Aero Engines and all material decisions require unanimous approval from the Company and Regional One, resulting in disproportionate ownership rights relative to voting rights. As unanimous approval is required for all Aero Engines’ material activities. Aero Engines has no primary beneficiary. The Company accounts for its investment in Aero Engines under the equity method. The Company’s exposure in its investment in Aero Engines primarily consists of the Company’s portion of income or loss from Aero Engines’ engine lease agreements with third parties and the Company’s ownership percentage in Aero Engines’ engines book value. Aero Engines had no debt outstanding as of December 31, 2022. As of December 31, 2022, the Company’s investment balance in Aero Engines was $26.6 million. The Company’s investment in Aero Engines has been recorded in “Other Assets” on the Company’s consolidated balance sheet. The Company’s portion of the earnings generated by Aero Engines for the year ended December 31, 2022, was $1.4 million, which is recorded in “Other income (expense), net” on the Company’s consolidated statements of comprehensive income (loss). Fair Value Method Investment During the year ended December 31, 2022, the Company acquired 1,000,000 shares of common stock of Eve and a warrant giving the Company the right to acquire 1,500,000 shares of common stock of Eve at an exercise price of $0.01 per share. The Company also received a put option from an Eve shareholder for the 1,000,000 shares of common stock of Eve payable in aircraft parts credits. The intent of the put option is to reduce the Company’s investment risk in Eve. The warrant expires in May 2032, and the put option expires in December 2031. The Company acquired the Eve Investments for $10.0 million. The Company evaluated the Eve Investments under ASC Topic 321, “Investments – Equity Securities” and ASC Topic 815, “Derivatives and Hedging,” and recorded the Eve Investments based on their pro rata share of the consideration paid using the fair value of the Eve Investments on the acquisition date, with subsequent changes in the fair value reported in earnings. The shares of common stock of Eve are classified as Level 1 within the fair value hierarchy as Eve stock is actively traded on the New York Stock Exchange, and the value is determined using quoted market prices for the equity security. The warrant and put option are classified as Level 3 within the fair value hierarchy, and the Company used the Black Scholes Option Pricing Model to determine the estimated fair market value of the warrant and put option, including an expected volatility of 49% , which is a significant unobservable input that was derived from historical volatility of comparable companies. The table below shows the reconciliation of the Level 3 warrant and put option Eve Investments (in thousands): ​ ​ ​ ​ ​ Level 3 Investments: ​ ​ Balance at December 31, 2021 $ — Purchases ​ 6,551 Unrealized gains ​ 7,629 Balance at December 31, 2022 ​ $ 14,180 ​ The Company recognized unrealized gains of $11.4 million in “Other income, net” on the Company’s consolidated statements of comprehensive income for the year ended December 31, 2022, related to the Eve Investments. As of December 31, 2022, the fair value of the Eve Investments was $21.4 million and was recorded in “Other Assets” on the Company’s consolidated balance sheet.

SCHEDULE II - VALUATION AND QUA

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Dec. 31, 2022
SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS
SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS	SKYWEST, INC. AND SUBSIDIARIES SCHEDULE II—VALUATION AND QUALIFYING ACCOUNTS For the Years Ended December 31, 2022, 2021 and 2020 (Dollars in thousands) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Additions ​ ​ ​ ​ ​ Balance at ​ Charged to ​ ​ ​ ​ ​ ​ ​ Beginning ​ Costs and ​ ​ ​ Balance at Description ​ of Year ​ Expenses ​ Deductions ​ End of Year Year Ended December 31, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for inventory obsolescence ​ $ 22,956 ​ 1,250 — $ 24,206 ​ Allowance for credit losses ​ ​ 41,976 ​ — (4,591) ​ 37,385 ​ ​ ​ $ 64,932 ​ 1,250 (4,591) $ 61,591 ​ Year Ended December 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for inventory obsolescence ​ $ 19,676 ​ 3,280 — $ 22,956 ​ Allowance for credit losses ​ ​ 46,225 ​ — (4,249) ​ 41,976 ​ ​ ​ $ 65,901 ​ 3,280 — $ 64,932 ​ Year Ended December 31, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Allowance for inventory obsolescence ​ $ 15,890 ​ 3,786 — $ 19,676 ​ Allowance for doubtful accounts receivable ​ ​ 18 ​ ​ — ​ (18) ​ ​ — ​ Allowance for credit losses (adoption of Topic 326) ​ ​ 15,388 ​ 30,837 — ​ 46,225 ​ ​ ​ $ 31,296 ​ 34,623 (18) ​ $ 65,901 ​ ​

Nature of Operations and Summ_2

Nature of Operations and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2022
Condensed Consolidated Financial Statements
Basis of Presentation	Basis of Presentation The Company’s consolidated financial statements include the accounts of the Company and the SkyWest Airlines and SkyWest Leasing segments, with all inter-company transactions and balances having been eliminated. In preparing the accompanying consolidated financial statements, the Company has reviewed, as determined necessary by the Company’s management, events that have occurred after December 31, 2022, through the filing date of the Company’s annual report with the U.S. Securities and Exchange Commission.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States (“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 and the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates and assumptions.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three months or less to be cash equivalents. The Company had no restricted cash as of December 31, 2022 and 2021.
Marketable securities	Marketable Securities The Company’s investments in debt securities are classified as available-for-sale and are reported at fair market value with the net unrealized depreciation reported as a component of accumulated other comprehensive income (loss) in stockholders’ equity. At the time of sale, any realized appreciation or depreciation, calculated by the specific identification method, is recognized in other income and expense. The Company’s position in marketable securities as of December 31, 2022 and 2021 was as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross unrealized ​ Gross unrealized ​ ​ ​ ​ At December 31, 2022 Amortized Cost holding gains holding losses Fair market value Marketable securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Bond and bond funds ​ $ 629,280 ​ $ — ​ $ (5,026) ​ $ 624,254 ​ Commercial Paper ​ 319,977 ​ — ​ — ​ 319,977 ​ Total marketable securities ​ $ 949,257 ​ $ — ​ $ (5,026) ​ $ 944,231 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross unrealized ​ ​ Gross unrealized ​ ​ ​ ​ At December 31, 2021 Amortized Cost holding gains holding losses Fair market value Marketable securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Bond and bond funds ​ $ 54,673 ​ $ — ​ $ — ​ $ 54,673 ​ Commercial Paper ​ 547,316 ​ — ​ — ​ 547,316 ​ Total marketable securities ​ $ 601,989 ​ $ — ​ $ — ​ $ 601,989 ​ ​
Inventories	Inventories Inventories include expendable parts, fuel and supplies and are valued at cost (FIFO basis) less an allowance for obsolescence based on historical results, excess parts and management’s expectations of future operations. Expendable inventory parts are charged to expense as used. An obsolescence allowance for flight equipment expendable parts is accrued based on estimated lives of the corresponding fleet types and salvage values. The inventory allowance as of December 31, 2022 and 2021, was $24.2 million and $23.0 million, respectively.
Property and Equipment	Property and Equipment Property and equipment are stated at cost and depreciated over their useful lives to their estimated residual values using the straight-line method as follows: ​ ​ ​ ​ ​ Assets ​ Depreciable Life ​ Current Residual Value Aircraft, rotable spares, and spare engines ​ up to 22 years up to 20 % Ground equipment ​ up to 10 years 0 % Office equipment ​ up to 7 years ​ 0 % Leasehold improvements ​ Shorter of 15 years or lease term 0 % Buildings ​ 20 - 39.5 years 0 %
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets As of December 31, 2022, the Company had approximately $5.5 billion of property and equipment, net. In accounting for these long-lived assets, the Company makes estimates about the expected useful lives of the assets, the expected residual values of certain of these assets, and the potential for impairment based on the fair value of the assets and the cash flows they generate. Factors indicating potential impairment include, but are not limited to, significant decreases in the market value of the long-lived assets, a significant change in the condition of the long-lived assets and operating cash flow losses associated with the use of the long-lived assets. On a periodic basis, the Company evaluates whether impairment indicators are present. When considering whether or not impairment of long- lived assets exists, the Company groups similar assets together at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities and compare the undiscounted cash flows for each asset group to the net carrying amount of the assets supporting the asset group. Asset groupings are done at the aircraft type level. During 2022, the Company committed to a plan to sell 14 CRJ700 aircraft, resulting in an impairment on the assets held for sale of $51.4 million. See Note 9, “Assets Held for Sale” for more information on the assets held for sale. During 2021, the Company recorded an impairment charge of $84.6 million to write-down certain CRJ900 aircraft to their estimated fair value. See Note 10, “Special Items” for more information on the CRJ900 impairment.
Capitalized Interest	Capitalized Interest Interest is capitalized on aircraft purchase deposits as a portion of the cost of the asset and is depreciated over the estimated useful life of the asset. During the years ended December 31, 2022 and 2021, the Company capitalized interest costs of approximately $1.9 million, and during the year ended December 31, 2020, the Company capitalized interest costs of approximately $1.7 million.
Maintenance	Maintenance The Company operates under a U.S. Federal Aviation Administration approved continuous inspection and maintenance program. The Company uses the direct expense method of accounting for its regional jet engine overhauls. The Company has engine services agreements with third-party vendors to provide long-term engine services covering the scheduled and unscheduled repairs for most of its aircraft. Under the terms of the agreements, the Company pays a fixed dollar amount per engine hour flown on a monthly basis and the third-party vendors will assume the responsibility to repair the engines at no additional cost to the Company, subject to certain specified exclusions. Maintenance costs under these contracts are recognized when the engine hour is flown pursuant to the terms of each contract. The costs of maintenance for airframe and avionics components, landing gear and other recurring maintenance are expensed as incurred. In 2020, the Company wrote-off $3.7 million of long-lived maintenance assets at maintenance locations the Company vacated during the year as a maintenance expense. There was not a similar expense in 2022 and 2021.
Flying Agreements and Airport Customer Service and Other Revenues	Flying Agreements and Airport Customer Service and Other Revenues The Company recognizes revenue under its flying agreements and under its lease, airport services and other service agreements when the service is provided under the applicable agreement. Under the Company’s capacity purchase agreements with United, Delta, American and Alaska (each, a “major airline partner”), the major airline partner generally pays the Company a fixed-fee for each departure, flight hour (measured from takeoff to landing, excluding taxi time) or block hour (measured from takeoff to landing, including taxi time) incurred, and an amount per aircraft in service each month with additional incentives based on flight completion and on-time performance. The major airline partner also directly pays for or reimburses the Company for certain direct expenses incurred under the capacity purchase agreement, such as fuel, airport landing fees and airport rents. Under the capacity purchase agreements, the Company’s performance obligation is met when each flight is completed, measured in completed block hours, and is reflected in flying agreements revenue. The transaction price for the capacity purchase agreements is determined from the fixed-fee consideration, incentive consideration and directly reimbursed expenses earned as flights are completed over the agreement term. For the years ended December 31, 2022, 2021 and 2020, capacity purchase arrangements represented approximately 88.0%, 84.3% and 87.0% of the Company’s flying agreements revenue, respectively. Under the Company’s prorate arrangements (also referred to as a “prorate” or “revenue-sharing” agreement), the major airline partner and the Company negotiate a passenger fare proration formula, pursuant to which the Company receives a percentage of the ticket revenues for those passengers traveling for one portion of their trip on a Company airline and the other portion of their trip on the major airline partner. Under the Company’s prorate flying agreements, the performance obligation is met and revenue is recognized when each flight is completed based upon the portion of the prorate passenger fare the Company determines that it will receive for each completed flight. The transaction price for the prorate agreements is determined from the proration formula derived from each passenger ticket amount on each completed flight over the agreement term. For the years ended December 31, 2022, 2021 and 2020, prorate flying agreements represented approximately 12.0%, 15.7%, and 13.0% of the Company’s flying agreements revenue, respectively. The following table represents the Company’s flying agreements revenue by type for the years ended December 31, 2022, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended December 31, ​ 2022 2021 ​ 2020 Capacity purchase agreements flight operations revenue (non-lease component) ​ $ 2,028,308 ​ ​ 1,678,219 ​ ​ 1,265,923 Capacity purchase agreements fixed aircraft lease revenue ​ ​ 504,529 ​ ​ 527,173 ​ ​ 526,018 Capacity purchase agreements variable aircraft lease revenue ​ 17,664 ​ ​ — ​ ​ — Prorate agreements revenue ​ 349,336 ​ ​ 409,684 ​ ​ 268,860 Flying agreements revenue ​ $ 2,899,837 $ 2,615,076 ​ $ 2,060,801 ​ The Company allocates the total consideration received under its capacity purchase agreements between the lease and non-lease components based on stand-alone selling prices. A portion of the Company’s compensation under its capacity purchase agreements is designed to reimburse the Company for certain aircraft ownership costs. The consideration for aircraft ownership costs varies by agreement but is intended to cover either the Company’s aircraft principal and interest debt service costs, its aircraft depreciation and interest expense or its aircraft lease expense costs while the aircraft is under contract. The consideration received for the use of the aircraft under the Company’s capacity purchase agreements is accounted for as lease revenue, inasmuch as the agreements identify the “right of use” of a specific type and number of aircraft over a stated period of time. The lease revenue associated with the Company’s capacity purchase agreements is accounted for as an operating lease and is reflected as flying agreements revenue on the Company’s consolidated statements of comprehensive income (loss). During the year ended December 31, 2022, the Company amended its capacity purchase agreements with certain major airline partners that reduced certain contractual fixed monthly payments and increased certain contractual variable payments. Accordingly, the Company re-evaluated the allocation of the total consideration between the lease and non-lease components for the amended agreements, including the allocation of the consideration to the fixed and variable lease components. As a result of these amendments, the Company deferred recognizing lease revenue on $22.1 million of the allocated fixed monthly lease payments received during the year ended December 31, 2022, under the straight-line method. The Company has not separately stated aircraft rental income and aircraft rental expense in the consolidated statement of comprehensive income (loss) because the use of the aircraft is not a separate activity of the total service provided under the capacity purchase agreements. A portion of the Company’s compensation under its capacity purchase agreements relates to operating the aircraft, identified as the non-lease component of the capacity purchase agreement. The Company recognizes revenue attributed to the non-lease component received as fixed-fees for each departure, flight hour or block hour on an as-completed basis for each reporting period. The Company recognizes revenue attributed to the non-lease component received as fixed monthly payments per aircraft proportionate to the number of block hours completed during each reporting period, relative to the estimated number of block hours the Company anticipates completing over the remaining contract term. Due to the lower number of block hours completed during 2020 as a result of the COVID-19 pandemic compared to historical levels, the amount of cash collected for the fixed amount per aircraft for operating the aircraft did not align with revenue recognized based on block hours completed. Accordingly, the Company deferred recognizing revenue on fixed monthly payments the Company received for operating the aircraft under its capacity purchase agreements beginning in 2020. In 2022, the Company deferred $18.7 million of fixed monthly payments under certain agreements and recognized $11.5 million of unbilled revenue under certain other agreements, compared to recognizing previously deferred revenue of $6.8 million and $8.4 million of unbilled revenue in 2021. The Company’s total deferred revenue balance, as of December 31, 2022, was $144.7 million, including $5.2 million in other current liabilities and $139.5 million in other long-term liabilities. The Company’s unbilled revenue balance as of December 31, 2022, was $19.9 million, including $9.9 million in other current assets and $10.0 million in other long-term assets. The Company’s deferred revenue balance as of December 31, 2021, was $103.9 million, including $24.5 million in other current liabilities and $79.4 million in other long-term liabilities. The Company’s unbilled revenue balance as of December 31, 2021, of $8.4 million was included in other long-term assets. In the event a flying agreement includes a mid-term rate reset to adjust rates prospectively and the contractual rates under the Company’s flying agreements have not been finalized at quarterly or annual financial statement dates, the Company applies the variable constraint guidance under Topic 606, where the Company records revenue to the extent it believes that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. In several of the Company’s agreements, the Company is eligible to receive incentive compensation upon the achievement of certain performance criteria. The incentives are defined in the agreements and are measured and determined on a monthly, quarterly or semi-annual basis. At the end of each period during the term of an agreement, the Company calculates the incentives achieved during that period and recognizes revenue attributable to that agreement accordingly, subject to the variable constraint guidance under Topic 606. The following summarizes the significant provisions of each code-share agreement the Company has with each major airline partner through SkyWest Airlines: United Express Agreements Agreement Aircraft type Number of Aircraft Term / Termination Dates United Express Agreements (capacity purchase agreement) ​ · E175 · CRJ 700 · CRJ 200 ​ 90 19 70 ​ · Individual aircraft have scheduled removal dates under the agreement between 2024 and 2029 · The average remaining term of the aircraft under contract is 3.5 years United Express Prorate Agreement (prorate agreement) ​ · CRJ 200 ​ 41* ​ · Terminable with 120 Total under United Express Agreements ​ ​ ​ 220 ​ ​ ​ Delta Connection Agreements Agreement Aircraft type Number of Aircraft Term / Termination Dates Delta Connection Agreement (capacity purchase agreement) ​ · E175 · CRJ 900 · CRJ 700 ​ 84 41 5 ​ · Individual aircraft have scheduled removal dates from 2023 to 2033 · The average remaining term of the aircraft under contract is 5.6 years Delta Connection Prorate Agreement (prorate agreement) ​ · CRJ 200 ​ 25* ​ · Terminable with 30 Total under Delta Connection Agreements ​ ​ ​ 155 ​ ​ ​ American Capacity Purchase Agreement Agreement Aircraft type Number of Aircraft Term / Termination Dates American Agreement (capacity purchase agreement) ​ · E175 · CRJ 700 ​ 20 80 ​ · Individual aircraft have scheduled removal dates from 2023 to 2032 · The average remaining term of the aircraft under contract is 4.3 years Total under American Agreement ​ ​ ​ 100 ​ ​ ​ Alaska Capacity Purchase Agreement Agreement Aircraft type Number of Aircraft Term / Termination Dates Alaska Agreement (capacity purchase agreement) ​ · E175 ​ 42 ​ · Individual aircraft have scheduled removal dates from 2030 to 2034 · The average remaining term of the aircraft under contract is 8.8 years ​ * The Company’s prorate agreements are based on specific routes, not a specific aircraft count. The number of aircraft listed above for each prorate agreement approximates the number of aircraft the Company uses to serve the prorate routes. In addition to the contractual arrangements described above, as of December 31, 2022, SkyWest Airlines has a capacity purchase agreement with Delta to place a total of three additional E175 aircraft into service, with delivery dates currently scheduled in 2023 and 2024. SkyWest Airlines has a capacity purchase agreement with Alaska to place one additional E175 aircraft into service with a delivery date currently scheduled for 2025. Final delivery and in-service dates for aircraft to be placed under contract may be adjusted based on various factors. When an aircraft is scheduled to be removed from a capacity purchase arrangement, the Company may, as practical under the circumstances, negotiate an extension with the respective major airline partner, negotiate the placement of the aircraft with another major airline partner, return the aircraft to the lessor if the aircraft is leased and the lease is expiring, place owned aircraft for sale, or pursue other uses for the aircraft. Other uses for the aircraft may include placing the aircraft in a prorate agreement, leasing the aircraft to a third party or parting out the aircraft to use the engines and parts as spare inventory or to lease the engines to a third party. Lease, airport services and other revenues primarily consists of revenue generated from aircraft and spare engines leased to third parties and airport customer services, such as gate and ramp agent services at applicable airports where the Company has agreements with third parties. The following table represents the Company’s lease, airport services and other revenues for the years ended December 31, 2022, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended December 31, ​ 2022 2021 ​ 2020 Operating lease revenue relating to lease payments ​ $ 48,714 ​ $ 46,532 ​ $ 34,791 Operating lease revenue relating to variable lease payments ​ ​ 17,050 ​ ​ 19,998 ​ ​ 5,710 Airport customer service and other revenue ​ ​ 39,324 ​ ​ 31,885 ​ ​ 25,804 Lease, airport services and other ​ $ 105,088 ​ $ 98,415 ​ $ 66,305 ​ ​ ​ ​ 2023 $ 45,900 2024 ​ 45,177 2025 ​ 40,207 2026 ​ 34,640 2027 ​ 34,619 Thereafter ​ 86,182 ​ ​ $ 286,725 Of the Company’s $5.5 billion of property and equipment, net as of December 31, 2022, $221.0 million of regional jet aircraft and spare engines were leased to third parties under operating leases. The Company’s mitigation strategy for the residual asset risks of these assets includes leasing aircraft and engine types that can be operated by the Company in the event of a default. Additionally, the operating leases typically have specified lease return condition requirements paid by the lessee to the Company and the Company typically maintains inspection rights under the leases. The transaction price for airport customer service agreements is determined from an agreed-upon rate by location applied to the applicable number of flights handled by the Company over the agreement term. The Company’s operating revenues could be impacted by several factors, including changes to the Company’s code-share agreements with its major airline partners, changes in flight schedules, contract modifications resulting from contract renegotiations, the Company’s ability to earn incentive payments contemplated under the Company’s code-share agreements and settlement of reimbursement disputes with the Company’s major airline partners. Other ancillary revenues commonly associated with airlines, such as baggage fee revenue, ticket change fee revenue and the marketing component of the sale of mileage credits, are retained by the Company’s major airline partners on flights that the Company operates under its code-share agreements. As of December 31, 2022, the Company had $100.5 million in accounts receivable of which $73.7 million related to flying agreements. As of December 31, 2021, the Company had $65.3 million in accounts receivable of which $50.8 million related to flying agreements.
Allowance for Credit Losses	Allowance for Credit Losses The Company adopted on January 1, 2020. At adoption, the Company’s primary financial assets included trade receivables from its flying agreements, a note receivable from the sale of the Company’s subsidiary, ExpressJet Airlines, Inc., in 2019, and receivables from aircraft manufacturers and other third parties in the airline industry. The Company recorded a credit loss of $11.6 million net of income tax in conjunction with the adoption of Topic 326. The Company recorded this credit loss as a January 1, 2020, beginning balance sheet entry to retained earnings (net of income tax). The Company monitors publicly available credit ratings for entities for which the Company has a significant receivable balance. As of December 31, 2022, the Company had gross receivables of $122.5 million in current assets and gross receivables of $210.5 million in other long-term assets. The Company has established credit loss reserves based on publicly available historic default rates issued by a third party for companies with similar credit ratings, factoring in the term of the respective accounts receivable or note receivable. During the year ended December 31, 2022, there were no significant changes in the outstanding accounts receivable or notes receivable or the credit ratings of the entities. The following table summarizes the changes in allowance for credit losses: ​ ​ ​ ​ ​ ​ Allowance for Credit Losses Balance at January 1, 2020 ​ ​ 15,388 Adjustments to credit loss reserves ​ ​ 30,837 Write-offs charged against allowance ​ ​ — Balance at December 31, 2020 ​ $ 46,225 Adjustments to credit loss reserves ​ ​ (4,249) Write-offs charged against allowance ​ ​ — Balance at December 31, 2021 ​ $ 41,976 Adjustments to credit loss reserves ​ (4,591) Write-offs charged against allowance ​ — Balance at December 31, 2022 ​ $ 37,385 ​ Income Taxes The Company recognizes a net liability or asset for the deferred tax consequences of all temporary differences between the tax basis of assets and liabilities and their reported amounts in the consolidated financial statements that are expected to result in taxable or deductible amounts in future years when the reported amounts of the assets and liabilities are recovered or settled.
Income Taxes	​ ​ ​ ​ ​ ​ Allowance for Credit Losses Balance at January 1, 2020 ​ ​ 15,388 Adjustments to credit loss reserves ​ ​ 30,837 Write-offs charged against allowance ​ ​ — Balance at December 31, 2020 ​ $ 46,225 Adjustments to credit loss reserves ​ ​ (4,249) Write-offs charged against allowance ​ ​ — Balance at December 31, 2021 ​ $ 41,976 Adjustments to credit loss reserves ​ (4,591) Write-offs charged against allowance ​ — Balance at December 31, 2022 ​ $ 37,385
Net Income (Loss) Per Common Share	Net Income (Loss) Per Common Share Basic net income (loss) per common share (“Basic EPS”) excludes dilution and is computed by dividing net income (loss) by the weighted average number of common shares outstanding during the period. Diluted net income per common share (“Diluted EPS”) reflects the potential dilution that could occur if stock options or other contracts to issue common stock were exercised or converted into common stock. The computation of Diluted EPS does not assume exercise or conversion of securities that would have an anti-dilutive effect on net income (loss) per common share. Securities that could potentially dilute Basic EPS in the future, and which were excluded from the calculation of Diluted EPS because inclusion of such share would be anti-dilutive, are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 PSP1 and Treasury Loan Warrants (1) ​ ​ 437 ​ ​ — ​ ​ 582 PSP2 Warrants (2) ​ ​ 125 ​ ​ — ​ ​ — PSP3 Warrants (3) ​ ​ 78 ​ ​ 78 ​ ​ — Employee Stock Awards ​ ​ 219 ​ ​ — ​ ​ 314 Total antidilutive securities ​ ​ 859 ​ ​ 78 ​ ​ 896 (1) Pursuant to the payroll support program established under the CARES Act (“PSP1”) and Loan and Guarantee Agreement with the U.S. Department of the Treasury (“U.S. Treasury”), SkyWest issued to Treasury warrants to purchase shares of SkyWest common stock for an exercise price of $28.38 per share. (2) Pursuant to the payroll support program established under the 2021 Consolidated Appropriations Act (“PSP2”), SkyWest issued to U.S. Treasury warrants to purchase shares of SkyWest common stock for an exercise price of $40.41 per share. (3) Pursuant to the payroll support program established under the American Rescue Plan (“PSP3”), SkyWest issued to U.S. Treasury warrants to purchase shares of SkyWest common stock for an exercise price of $57.47 per share. Additionally, for the years ended December 31, 2022, 2021 and 2020, 146,000, 140,000 and 178,000 performance share units (at target performance) were excluded from the computation of Diluted EPS since the Company had not achieved the minimum target thresholds as of December 31, 2022, 2021 and 2020, respectively. The calculation of the weighted average number of common shares outstanding for Basic EPS and Diluted EPS are as follows for the years ended December 31, 2022, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Numerator: ​ ​ ​ ​ Net income (loss) ​ $ 72,953 ​ $ 111,910 ​ $ (8,515) Denominator: ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings per share weighted average shares ​ 50,548 ​ 50,348 ​ 50,195 Dilution due to employee equity awards and warrants ​ 96 ​ 405 ​ — Diluted earnings per share weighted average shares ​ 50,644 ​ 50,753 ​ 50,195 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings (loss) per share ​ $ 1.44 ​ $ 2.22 ​ $ (0.17) Diluted earnings (loss) per share ​ $ 1.44 ​ $ 2.20 ​ $ (0.17) ​ Comprehensive Income (Loss) Comprehensive income (loss) includes charges and credits to stockholders’ equity that are not the result of transactions with the Company’s shareholders, including changes in unrealized appreciation (or depreciation) on marketable debt securities.
Comprehensive Income (Loss)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Numerator: ​ ​ ​ ​ Net income (loss) ​ $ 72,953 ​ $ 111,910 ​ $ (8,515) Denominator: ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings per share weighted average shares ​ 50,548 ​ 50,348 ​ 50,195 Dilution due to employee equity awards and warrants ​ 96 ​ 405 ​ — Diluted earnings per share weighted average shares ​ 50,644 ​ 50,753 ​ 50,195 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings (loss) per share ​ $ 1.44 ​ $ 2.22 ​ $ (0.17) Diluted earnings (loss) per share ​ $ 1.44 ​ $ 2.20 ​ $ (0.17) ​
Fair Value of Financial Instruments	Fair Value of Financial Instruments The carrying amounts reported in the consolidated balance sheets for receivables and accounts payable approximate fair values because of the immediate or short-term maturity of these financial instruments. Marketable securities are reported at fair value based on market quoted prices in the consolidated balance sheets. If quoted prices in active markets are no longer available, the Company has estimated the fair values of these securities utilizing a discounted cash flow analysis. These analyses consider, among other items, the collateralization underlying the security investments, the creditworthiness of the counterparty, the timing of expected future cash flows, and the expectation of the next time the security is expected to have a successful auction. Certain investments in other companies are reported at fair value based on market quoted prices or using the Black Scholes Option Pricing model in the consolidated balance sheets. The fair value of the Company’s long-term debt is estimated based on current rates offered to the Company for similar debt.
Segment Reporting	Segment Reporting GAAP requires disclosures related to components of a company for which separate financial information is available to, and regularly evaluated by, the Company’s chief operating decision maker when deciding how to allocate resources and in assessing performance. The Company has two reportable segments: SkyWest Airlines and SkyWest Leasing. Information pertaining to the Company’s reportable segments is presented in Note 3, Segment Reporting

Nature of Operations and Summ_3

Nature of Operations and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2022
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Schedule of number of aircraft held by entity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ E175 CRJ900 CRJ700 CRJ200 Total United 90 ​ — ​ 19 ​ 111 ​ 220 Delta ​ 84 ​ 41 ​ 5 ​ 25 ​ 155 American 20 ​ — ​ 80 ​ — ​ 100 Alaska 42 ​ — ​ — ​ — ​ 42 Aircraft in scheduled service or under contract ​ 236 ​ 41 ​ 104 ​ 136 ​ 517 Leased to third parties — ​ 5 ​ 35 ​ — ​ 40 Other* — ​ 3 ​ 28 ​ 37 ​ 68 Total Fleet 236 ​ 49 ​ 167 ​ 173 ​ 625 *As of December 31, 2022, other aircraft included: supplemental spare aircraft supporting the Company’s code-share agreements that may be used in future code-share or leasing arrangements, aircraft transitioning between code-share agreements with the Company’s major airline partners, aircraft held for sale or aircraft that are scheduled to be disassembled for use as spare parts.
Schedule of marketable securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross unrealized ​ Gross unrealized ​ ​ ​ ​ At December 31, 2022 Amortized Cost holding gains holding losses Fair market value Marketable securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Bond and bond funds ​ $ 629,280 ​ $ — ​ $ (5,026) ​ $ 624,254 ​ Commercial Paper ​ 319,977 ​ — ​ — ​ 319,977 ​ Total marketable securities ​ $ 949,257 ​ $ — ​ $ (5,026) ​ $ 944,231 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross unrealized ​ ​ Gross unrealized ​ ​ ​ ​ At December 31, 2021 Amortized Cost holding gains holding losses Fair market value Marketable securities: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Bond and bond funds ​ $ 54,673 ​ $ — ​ $ — ​ $ 54,673 ​ Commercial Paper ​ 547,316 ​ — ​ — ​ 547,316 ​ Total marketable securities ​ $ 601,989 ​ $ — ​ $ — ​ $ 601,989 ​
Schedule of property and equipment	​ ​ ​ ​ ​ Assets ​ Depreciable Life ​ Current Residual Value Aircraft, rotable spares, and spare engines ​ up to 22 years up to 20 % Ground equipment ​ up to 10 years 0 % Office equipment ​ up to 7 years ​ 0 % Leasehold improvements ​ Shorter of 15 years or lease term 0 % Buildings ​ 20 - 39.5 years 0 %
Schedule of aircraft and agreements with major airline partners	United Express Agreements Agreement Aircraft type Number of Aircraft Term / Termination Dates United Express Agreements (capacity purchase agreement) ​ · E175 · CRJ 700 · CRJ 200 ​ 90 19 70 ​ · Individual aircraft have scheduled removal dates under the agreement between 2024 and 2029 · The average remaining term of the aircraft under contract is 3.5 years United Express Prorate Agreement (prorate agreement) ​ · CRJ 200 ​ 41* ​ · Terminable with 120 Total under United Express Agreements ​ ​ ​ 220 ​ ​ ​ Delta Connection Agreements Agreement Aircraft type Number of Aircraft Term / Termination Dates Delta Connection Agreement (capacity purchase agreement) ​ · E175 · CRJ 900 · CRJ 700 ​ 84 41 5 ​ · Individual aircraft have scheduled removal dates from 2023 to 2033 · The average remaining term of the aircraft under contract is 5.6 years Delta Connection Prorate Agreement (prorate agreement) ​ · CRJ 200 ​ 25* ​ · Terminable with 30 Total under Delta Connection Agreements ​ ​ ​ 155 ​ ​ ​ American Capacity Purchase Agreement Agreement Aircraft type Number of Aircraft Term / Termination Dates American Agreement (capacity purchase agreement) ​ · E175 · CRJ 700 ​ 20 80 ​ · Individual aircraft have scheduled removal dates from 2023 to 2032 · The average remaining term of the aircraft under contract is 4.3 years Total under American Agreement ​ ​ ​ 100 ​ ​ ​ Alaska Capacity Purchase Agreement Agreement Aircraft type Number of Aircraft Term / Termination Dates Alaska Agreement (capacity purchase agreement) ​ · E175 ​ 42 ​ · Individual aircraft have scheduled removal dates from 2030 to 2034 · The average remaining term of the aircraft under contract is 8.8 years
Schedule of future minimum rental payments for operating leases	The following table summarizes future minimum rental payments primarily related to leased aircraft and maintenance facilities required under operating leases that had initial or remaining non-cancelable lease terms as of December 31, 2022 (in thousands): ​ ​ ​ ​ ​ 2023 $ 74,557 2024 ​ 32,525 2025 ​ 15,837 2026 ​ 13,427 2027 ​ 12,291 Thereafter ​ 54,298 ​ ​ $ 202,935 ​
Schedule of allowance for credit losses	The following table summarizes the changes in allowance for credit losses: ​ ​ ​ ​ ​ ​ Allowance for Credit Losses Balance at January 1, 2020 ​ ​ 15,388 Adjustments to credit loss reserves ​ ​ 30,837 Write-offs charged against allowance ​ ​ — Balance at December 31, 2020 ​ $ 46,225 Adjustments to credit loss reserves ​ ​ (4,249) Write-offs charged against allowance ​ ​ — Balance at December 31, 2021 ​ $ 41,976 Adjustments to credit loss reserves ​ (4,591) Write-offs charged against allowance ​ — Balance at December 31, 2022 ​ $ 37,385 ​
Schedule of net income (loss) per common share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Numerator: ​ ​ ​ ​ Net income (loss) ​ $ 72,953 ​ $ 111,910 ​ $ (8,515) Denominator: ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings per share weighted average shares ​ 50,548 ​ 50,348 ​ 50,195 Dilution due to employee equity awards and warrants ​ 96 ​ 405 ​ — Diluted earnings per share weighted average shares ​ 50,644 ​ 50,753 ​ 50,195 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic earnings (loss) per share ​ $ 1.44 ​ $ 2.22 ​ $ (0.17) Diluted earnings (loss) per share ​ $ 1.44 ​ $ 2.20 ​ $ (0.17)
Schedule of antidilutive securities excluded from calculation of diluted EPS	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year Ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 PSP1 and Treasury Loan Warrants (1) ​ ​ 437 ​ ​ — ​ ​ 582 PSP2 Warrants (2) ​ ​ 125 ​ ​ — ​ ​ — PSP3 Warrants (3) ​ ​ 78 ​ ​ 78 ​ ​ — Employee Stock Awards ​ ​ 219 ​ ​ — ​ ​ 314 Total antidilutive securities ​ ​ 859 ​ ​ 78 ​ ​ 896 (1) Pursuant to the payroll support program established under the CARES Act (“PSP1”) and Loan and Guarantee Agreement with the U.S. Department of the Treasury (“U.S. Treasury”), SkyWest issued to Treasury warrants to purchase shares of SkyWest common stock for an exercise price of $28.38 per share. (2) Pursuant to the payroll support program established under the 2021 Consolidated Appropriations Act (“PSP2”), SkyWest issued to U.S. Treasury warrants to purchase shares of SkyWest common stock for an exercise price of $40.41 per share. (3) Pursuant to the payroll support program established under the American Rescue Plan (“PSP3”), SkyWest issued to U.S. Treasury warrants to purchase shares of SkyWest common stock for an exercise price of $57.47 per share.
Flying agreements
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Schedule of revenue by type	The following table represents the Company’s flying agreements revenue by type for the years ended December 31, 2022, 2021 and 2020 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended December 31, ​ 2022 2021 ​ 2020 Capacity purchase agreements flight operations revenue (non-lease component) ​ $ 2,028,308 ​ ​ 1,678,219 ​ ​ 1,265,923 Capacity purchase agreements fixed aircraft lease revenue ​ ​ 504,529 ​ ​ 527,173 ​ ​ 526,018 Capacity purchase agreements variable aircraft lease revenue ​ 17,664 ​ ​ — ​ ​ — Prorate agreements revenue ​ 349,336 ​ ​ 409,684 ​ ​ 268,860 Flying agreements revenue ​ $ 2,899,837 $ 2,615,076 ​ $ 2,060,801
Airport customer service and other revenue
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Schedule of revenue by type	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended December 31, ​ 2022 2021 ​ 2020 Operating lease revenue relating to lease payments ​ $ 48,714 ​ $ 46,532 ​ $ 34,791 Operating lease revenue relating to variable lease payments ​ ​ 17,050 ​ ​ 19,998 ​ ​ 5,710 Airport customer service and other revenue ​ ​ 39,324 ​ ​ 31,885 ​ ​ 25,804 Lease, airport services and other ​ $ 105,088 ​ $ 98,415 ​ $ 66,305
Aircraft
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Schedule of future minimum rental payments for operating leases	​ ​ ​ ​ 2023 $ 45,900 2024 ​ 45,177 2025 ​ 40,207 2026 ​ 34,640 2027 ​ 34,619 Thereafter ​ 86,182 ​ ​ $ 286,725

Recovery from the COVID-19 Pa_2

Recovery from the COVID-19 Pandemic and Labor Impact (Tables)	12 Months Ended
	Dec. 31, 2022
Recovery from the COVID-19 Pandemic and Labor Impact
Summary of amount received and warrants issued	The following table summarizes the amounts received and warrants issued under the payroll support programs and secured loan facility (in thousands except warrant amounts): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total ​ Grant Loan ​ Number of Warrants PSP1 ​ $ 450,701 ​ $ 345,491 ​ $ 105,210 ​ 370,720 Secured Loan ​ ​ 60,000 ​ ​ — ​ ​ 60,000 ​ 211,416 PSP2 ​ ​ 268,070 ​ ​ 217,649 ​ ​ 50,421 ​ 124,773 PSP3 ​ 250,029 ​ 205,020 ​ 45,009 ​ 78,317 Total ​ $ 1,028,800 ​ $ 768,160 ​ $ 260,640 ​ 785,226

Segment Reporting (Tables)

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2022
Segment Reporting
Schedule of Company's segment data	The following represents the Company’s segment data for the years ended December 31, 2022, 2021, and 2020 (in thousands). ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2022 ​ ​ SkyWest ​ SkyWest ​ ​ ​ Airlines Leasing Consolidated Operating revenues (1) ​ $ 2,492,318 ​ $ 512,607 ​ $ 3,004,925 Operating expense ​ 2,525,076 ​ 298,687 ​ 2,823,763 Depreciation and amortization expense ​ 182,475 ​ 212,077 ​ 394,552 Interest expense ​ 12,805 ​ 114,278 ​ 127,083 Segment profit (loss) (2) ​ (45,563) ​ 99,642 ​ 54,079 Total assets (as of December 31, 2022) ​ 2,977,804 ​ 4,436,749 ​ 7,414,553 Capital expenditures (including non-cash) ​ 82,891 ​ 579,426 ​ 662,317 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2021 ​ ​ SkyWest ​ SkyWest ​ ​ ​ Airlines Leasing Consolidated Operating revenues (1) ​ $ 2,192,432 ​ $ 521,059 ​ $ 2,713,491 Operating expense ​ 2,177,524 ​ 260,100 ​ 2,437,624 Depreciation and amortization expense ​ 210,281 ​ 229,917 ​ 440,198 Special items - impairment charges ​ ​ 84,592 ​ ​ — ​ ​ 84,592 Interest expense ​ 13,360 ​ 109,762 ​ 123,122 Segment profit (2) ​ 1,548 ​ 151,197 ​ 152,745 Total assets (as of December 31, 2021) ​ 2,957,745 ​ ​ 4,168,202 ​ 7,125,947 Capital expenditures (including non-cash) ​ 128,712 ​ ​ 438,325 ​ 567,037 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, 2020 ​ ​ SkyWest ​ SkyWest ​ ​ ​ Airlines Leasing Consolidated Operating revenues (1) ​ $ 1,636,762 ​ $ 490,344 ​ $ 2,127,106 Operating expense ​ 1,716,808 ​ 301,496 ​ 2,018,304 Depreciation and amortization expense ​ 221,216 ​ 253,743 ​ 474,959 Interest expense ​ 12,381 ​ 110,792 ​ 123,173 Segment profit (loss) (2) ​ (92,427) ​ 78,056 ​ (14,371) Total assets (as of December 31, 2020) ​ 2,804,259 ​ ​ 4,083,363 ​ 6,887,622 Capital expenditures (including non-cash) ​ 124,825 ​ ​ 335,658 ​ 460,483 (1) Prorate revenue and airport customer service revenue are primarily reflected in the SkyWest Airlines segment. (2) Segment profit (loss) is equal to operating income less interest expense.

Long-term Debt (Tables)

Long-term Debt (Tables)	12 Months Ended
	Dec. 31, 2022
Long-term Debt
Schedule of long-term debt	Long-term debt consisted of the following as of December 31, 2022 and 2021 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, December 31, ​ ​ 2022 ​ 2021 Notes payable to banks, due in quarterly installments, plus interest at 2.33% to 5.95% through 2034, secured by aircraft ​ $ 2,604,058 ​ $ 2,535,827 ​ Notes payable to banks, due in monthly or semi-annual installments, plus interest at 2.68% to 5.66% through 2032, secured by aircraft and engines ​ 604,613 ​ 404,471 ​ Notes payable to U.S. Government, interest due quarterly at 1.00% through 2025 and based on SOFR plus spread from 2025 through 2031, unsecured ​ 200,640 ​ 200,640 ​ Long-term debt ​ $ 3,409,311 ​ $ 3,140,938 ​ Current portion of long-term debt ​ (442,360) ​ (395,371) ​ Less long-term portion of unamortized debt issue cost, net ​ ​ (25,179) ​ ​ (28,147) ​ Long-term debt, net of current maturities and debt issue costs ​ $ 2,941,772 ​ $ 2,717,420 ​ ​ ​ ​ ​ ​ ​ ​ ​ Current portion of long-term debt ​ 442,360 ​ 395,371 ​ Less current portion of unamortized debt issue cost, net ​ ​ (3,858) ​ ​ (3,573) ​ Current portion of long-term debt, net of debt issue costs ​ $ 438,502 ​ $ 391,798 ​
Schedule of maturities of long-term debt	The aggregate amounts of principal maturities of long-term debt as of December 31, 2022 were as follows (in thousands): ​ ​ ​ ​ ​ 2023 $ 442,360 2024 ​ 443,642 ​ 2025 ​ 527,564 ​ 2026 ​ 504,269 ​ 2027 ​ 457,326 ​ Thereafter ​ 1,034,150 ​ ​ ​ $ 3,409,311 ​
Carrying value and fair value of long-term debt	​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2022 ​ December 31, 2021 Carrying value ​ $ 3,409,311 ​ $ 3,140,938 Fair value ​ $ 3,264,704 ​ $ 3,132,072

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2022
Income Taxes
Schedule of components of provision (benefit) for income taxes	The provision for income taxes includes the following components (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Current tax provision (benefit): ​ ​ ​ ​ Federal ​ $ (7,319) ​ $ — ​ $ (4,397) ​ State ​ 1,813 ​ 846 ​ (875) ​ ​ ​ (5,506) ​ 846 ​ (5,272) ​ Deferred tax provision (benefit): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ 21,587 ​ 32,510 ​ 6,659 ​ State ​ 3,549 ​ 5,344 ​ (199) ​ ​ ​ 25,136 ​ 37,854 ​ 6,460 ​ Provision for income taxes ​ $ 19,630 ​ $ 38,700 ​ $ 1,188 ​
Schedule of income tax rate reconciliation	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Current tax provision (benefit): ​ ​ ​ ​ Federal ​ $ (7,319) ​ $ — ​ $ (4,397) ​ State ​ 1,813 ​ 846 ​ (875) ​ ​ ​ (5,506) ​ 846 ​ (5,272) ​ Deferred tax provision (benefit): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Federal ​ 21,587 ​ 32,510 ​ 6,659 ​ State ​ 3,549 ​ 5,344 ​ (199) ​ ​ ​ 25,136 ​ 37,854 ​ 6,460 ​ Provision for income taxes ​ $ 19,630 ​ $ 38,700 ​ $ 1,188 ​
Schedule of components of the net deferred tax assets and liabilities	The significant components of the Company’s net deferred tax assets and liabilities as of December 31, 2022 and 2021, are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2022 ​ 2021 Deferred tax assets: ​ ​ ​ Accrued benefits ​ $ 29,154 ​ $ 21,401 ​ Net operating loss carryforward ​ 186,517 ​ 175,659 ​ Aircraft credits ​ 77,962 ​ 22,265 ​ Deferred revenue ​ ​ 35,385 ​ ​ 25,405 ​ Operating lease liabilities ​ ​ 39,209 ​ ​ 57,991 ​ Interest deduction limitation ​ ​ 26,469 ​ ​ — ​ Accrued reserves and other ​ 49,972 ​ 31,431 ​ Total deferred tax assets ​ 444,668 ​ 334,152 ​ Valuation allowance ​ (1,716) ​ — ​ Deferred tax liabilities: ​ ​ ​ ​ ​ ​ ​ Accelerated depreciation ​ (1,094,538) ​ (940,867) ​ Operating lease right-of-use assets ​ ​ (35,474) ​ ​ (56,521) ​ Total deferred tax liabilities ​ (1,130,012) ​ (997,388) ​ Net deferred tax liability ​ $ (687,060) ​ $ (663,236) ​
Schedule of unrecognized tax benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits for the year ended December 31, 2022, 2021, and 2020 is as follows (in thousands) : ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Unrecognized tax benefits at the beginning of year $ 15,529 $ 14,980 $ 14,620 Gross increases - current year tax positions ​ ​ — ​ ​ — ​ ​ — Gross increases - prior year tax positions ​ 343 ​ 549 ​ 360 Gross decreases - prior year tax positions ​ ​ (7,662) ​ ​ — ​ ​ — Unrecognized tax benefits at end of year ​ $ 8,210 ​ $ 15,529 ​ $ 14,980 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Interest and penalties in year-end balance ​ $ 607 ​ $ 976 ​ $ 427

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2022
Leases
Summary of related terms and discount rates	​ ​ ​ ​ As of December 31, 2022 Weighted-average remaining lease term for operating leases 6.5 years Weighted-average discount rate for operating leases 6.1%
Summary of lease costs	​ ​ ​ ​ As of December 31, 2022 Weighted-average remaining lease term for operating leases 6.5 years Weighted-average discount rate for operating leases 6.1% ​ The Company’s lease costs for 2022 and 2021 included the following components (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ For the year ended December 31, ​ 2022 2021 Operating lease cost ​ $ 97,998 ​ $ 89,891 Variable and short-term lease cost ​ 1,830 ​ 4,468 Sublease income ​ ​ (7,089) ​ ​ (6,552) Total lease cost ​ $ 92,739 ​ $ 87,807
Schedule of future minimum rental payments for operating leases	The following table summarizes future minimum rental payments primarily related to leased aircraft and maintenance facilities required under operating leases that had initial or remaining non-cancelable lease terms as of December 31, 2022 (in thousands): ​ ​ ​ ​ ​ 2023 $ 74,557 2024 ​ 32,525 2025 ​ 15,837 2026 ​ 13,427 2027 ​ 12,291 Thereafter ​ 54,298 ​ ​ $ 202,935 ​

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2022
Fair Value Measurements
Schedule of assets measured at fair value on a recurring basis	​ As of December 31, 2022 and 2021, the Company held certain assets that are required to be measured at fair value on a recurring basis. Assets measured at fair value on a recurring basis are summarized below (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements as of December 31, 2022 ​ Total Level 1 Level 2 Level 3 Marketable Securities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Bonds and bond funds ​ $ 624,254 ​ $ — ​ $ 624,254 ​ $ — Commercial paper ​ 319,977 ​ — ​ 319,977 ​ — ​ ​ $ 944,231 ​ $ — ​ $ 944,231 ​ $ — Investments in Other Companies ​ ​ 21,380 ​ ​ 7,200 ​ ​ — ​ ​ 14,180 Cash and Cash Equivalents ​ ​ 102,984 ​ ​ 102,984 ​ ​ — ​ ​ — Total Assets Measured at Fair Value ​ $ 1,068,595 ​ $ 110,184 ​ $ 944,231 ​ $ 14,180 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements as of December 31, 2021 ​ ​ Total ​ Level 1 ​ Level 2 ​ Level 3 Marketable Securities ​ ​ ​ ​ Bonds and bond funds ​ $ 54,673 ​ $ — ​ $ 54,673 ​ $ — Commercial paper ​ 547,316 ​ — ​ 547,316 ​ — ​ ​ $ 601,989 ​ $ — ​ $ 601,989 ​ $ — Cash and Cash Equivalents ​ ​ 258,421 ​ ​ 258,421 ​ ​ — ​ ​ — Total Assets Measured at Fair Value ​ $ 860,410 ​ $ 258,421 ​ $ 601,989 ​ $ —

Capital Transactions (Tables)

Capital Transactions (Tables)	12 Months Ended
	Dec. 31, 2022
Schedule of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2022 ​ 2021 ​ 2020 ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ Average ​ ​ Aggregate ​ ​ ​ Weighted ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ Remaining ​ ​ Intrinsic ​ ​ ​ Average ​ ​ ​ Average ​ ​ Number of ​ Exercise ​ Contractual ​ ​ Value ​ Number of ​ Exercise ​ Number of ​ Exercise ​ ​ Options ​ Price ​ Term ​ ​ ($000) ​ Options ​ Price ​ Options ​ Price Outstanding at beginning of year 16,633 ​ $ 14.62 1.0 years ​ $ 410.4 57,653 $ 14.74 60,231 $ 14.74 ​ Granted — ​ — ​ ​ ​ ​ ​ ​ — ​ — — ​ — ​ Exercised (9,817) ​ 14.52 ​ ​ ​ ​ ​ ​ (41,020) ​ 14.78 (2,578) ​ 14.78 ​ Cancelled — ​ — ​ ​ ​ ​ ​ ​ — ​ — — ​ — ​ Outstanding at end of year 6,816 ​ $ 14.78 0.1 years ​ $ 11.8 16,633 ​ 14.62 57,653 ​ 14.74 ​ Exercisable at December 31, 2022 6,816 ​ $ 14.78 ​ 0.1 years ​ $ 11.8 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Exercisable at December 31, 2021 16,633 ​ $ 14.62 ​ 1.0 year ​ $ 410.4 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of stock options outstanding	The following table summarizes information about the Company’s stock options outstanding at December 31, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Options Outstanding ​ Options Exercisable ​ ​ ​ ​ ​ ​ Weighted Average ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Number ​ Remaining ​ Weighted Average ​ Number ​ Weighted Average Range of Exercise Prices ​ Outstanding ​ Contractual Life ​ Exercise Price ​ Exercisable ​ Exercise Price $14.00 to $15.00 6,816 0.1 years ​ 14.78 6,816 ​ 14.78 ​
Schedule of restricted stock activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ ​ Grant-Date Fair ​ ​ Number of RSUs ​ ​ Value Non-vested RSUs outstanding at December 31, 2019 284,686 ​ $ 45.21 ​ Granted 82,505 ​ 61.45 ​ Vested (103,231) ​ 35.81 ​ Cancelled (25,983) ​ 52.31 ​ Non-vested RSUs outstanding at December 31, 2020 237,977 ​ $ 54.15 ​ Granted 44,770 ​ 44.87 ​ Vested (69,184) ​ 53.41 ​ Cancelled (13,390) ​ 52.28 ​ Non-vested RSUs outstanding at December 31, 2021 200,173 ​ $ 52.45 ​ Granted 66,680 ​ 32.86 ​ Vested (86,534) ​ 48.69 ​ Cancelled (20,297) ​ 44.91 ​ Non-vested RSUs outstanding at December 31, 2022 160,022 ​ $ 47.28 ​
Performance Share Units (PSUs)
Schedule of non-vested stock options	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted-Average ​ ​ ​ ​ ​ Grant-Date Fair ​ ​ Number of PSUs ​ ​ Value Non-vested PSUs outstanding at December 31, 2019 233,571 ​ $ 45.44 Granted 69,132 ​ 61.45 Additional PSUs awarded from the 2017 grant ​ 83,042 ​ ​ 35.81 Vested (166,084) ​ 35.81 Cancelled (23,052) ​ 53.66 Non-vested PSUs outstanding at December 31, 2020 196,609 ​ $ 54.17 Granted 157,210 ​ 44.87 PSUs forfeited from the 2018 grant ​ (11,392) ​ ​ 53.41 Vested (45,644) ​ 53.41 Cancelled (3,991) ​ 53.30 Non-vested PSUs outstanding at December 31, 2021 292,792 ​ $ 49.39 Granted 225,345 ​ 32.73 PSUs forfeited from the 2019 grant ​ (45,695) ​ ​ 48.87 Vested (30,480) ​ 48.87 Cancelled (13,032) ​ 41.81 Non-vested PSUs outstanding at December 31, 2022 428,930 ​ $ 40.96

Retirement Plans and Employee_2

Retirement Plans and Employee Stock Purchase Plans (Tables)	12 Months Ended
	Dec. 31, 2022
Retirement Plans and Employee Stock Purchase Plans
Schedule of purchases made under the 2009 Employee Stock Purchase Plans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Year ended December 31, ​ ​ 2022 ​ 2021 ​ 2020 Number of shares purchased ​ 105,606 ​ 63,962 ​ 65,512 ​ Average price of shares purchased ​ $ 26.66 ​ $ 39.70 ​ $ 42.45 ​

Investments in Other Companies

Investments in Other Companies (Tables)	12 Months Ended
	Dec. 31, 2022
Investments in Other Companies
Schedule of reconciliation of Level 3 investments	The table below shows the reconciliation of the Level 3 warrant and put option Eve Investments (in thousands): ​ ​ ​ ​ ​ Level 3 Investments: ​ ​ Balance at December 31, 2021 $ — Purchases ​ 6,551 Unrealized gains ​ 7,629 Balance at December 31, 2022 ​ $ 14,180

Nature of Operations and Summ_4

Nature of Operations and Summary of Significant Accounting Policies - Aircraft Fleet (Details)	12 Months Ended
	Dec. 31, 2022 aircraft
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of daily departures	1,620
Number of aircraft held by entity	625
E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	236
E175 | Minimum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	65
E175 | Maximum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	76
CRJ 900
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	49
CRJ 900 | Minimum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	65
CRJ 900 | Maximum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	76
CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	167
CRJ 700 | Minimum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	65
CRJ 700 | Maximum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	76
CRJ 200
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	173
Number of seats on aircraft	50
United
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	220
Percentage of aggregate capacity operated	42.60%
United | E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	90
United | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	19
United | CRJ 200
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	111
Delta
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	155
Percentage of aggregate capacity operated	30%
Delta | E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	84
Delta | CRJ 900
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	41
Delta | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	5
Delta | CRJ 200
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	25
American
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	100
Percentage of aggregate capacity operated	19.30%
American | E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	20
American | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	80
Alaska
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	42
Percentage of aggregate capacity operated	8.10%
Alaska | E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	42
Aircraft in schedule service or under contract
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	517
Aircraft in schedule service or under contract | E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	236
Aircraft in schedule service or under contract | CRJ 900
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	41
Aircraft in schedule service or under contract | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	104
Aircraft in schedule service or under contract | CRJ 200
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	136
Leased to third parties
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	40
Leased to third parties | CRJ 900
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	5
Leased to third parties | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	35
Other
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	68
Other | CRJ 900
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	3
Other | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	28
Other | CRJ 200
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	37

Nature of Operations and Summ_5

Nature of Operations and Summary of Significant Accounting Policies - Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Condensed Consolidated Financial Statements
Restricted cash	$ 0	$ 0

Nature of Operations and Summ_6

Nature of Operations and Summary of Significant Accounting Policies - Marketable Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Total cash and cash equivalents	$ 102,984	$ 258,421
Amortized Cost	949,257	601,989
Gross unrealized holding losses	(5,026)
Fair market value	$ 944,231	601,989
Marketable Securities
Maximum period for redemption	1 year
Corporate Bond Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 629,280	54,673
Gross unrealized holding losses	(5,026)
Fair market value	624,254	54,673
Commercial Paper
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	319,977	547,316
Fair market value	$ 319,977	$ 547,316

Nature of Operations and Summ_7

Nature of Operations and Summary of Significant Accounting Policies - Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Inventories
Inventory allowance	$ 24.2	$ 23

Nature of Operations and Summ_8

Nature of Operations and Summary of Significant Accounting Policies - Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2022
Aircraft and rotable spares | Maximum
Property and Equipment
Depreciable Life	22 years
Residual Value (as a percent)	20%
Ground equipment
Property and Equipment
Residual Value (as a percent)	0%
Ground equipment | Maximum
Property and Equipment
Depreciable Life	10 years
Office Equipment
Property and Equipment
Residual Value (as a percent)	0%
Office Equipment | Maximum
Property and Equipment
Depreciable Life	7 years
Leasehold Improvements
Property and Equipment
Residual Value (as a percent)	0%
Leasehold Improvements | Maximum
Property and Equipment
Depreciable Life	15 years
Building
Property and Equipment
Residual Value (as a percent)	0%
Building | Minimum
Property and Equipment
Depreciable Life	20 years
Building | Maximum
Property and Equipment
Depreciable Life	39 years 6 months

Nature of Operations and Summ_9

Nature of Operations and Summary of Significant Accounting Policies - Long-Lived Assets (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) aircraft	Dec. 31, 2021 USD ($)
Impairment of Long Lived and Intangible Assets
Property and equipment and related assets	$ 5,548,480	$ 5,498,599
Number of aircraft held-for-sale | aircraft	14
Impairment on assets held for sale	$ 51,384
CRJ 900
Impairment of Long Lived and Intangible Assets
Impairment charges		$ 84,600

Nature of Operations and Sum_10

Nature of Operations and Summary of Significant Accounting Policies - Capitalized Interest and Maintenance (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Capitalized Interest
Capitalized interest costs	$ 1.9	$ 1.9	$ 1.7
Long-lived maintenance assets written off			$ 3.7

Nature of Operations and Sum_11

Nature of Operations and Summary of Significant Accounting Policies - Flying Agreements (Details) $ in Thousands		12 Months Ended
	Jan. 01, 2020 USD ($)	Dec. 31, 2022 USD ($) aircraft	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Agreements with other airlines
Percentage of ASMs flown under fixed-fee arrangements		88%	84.30%	87%
Percentage of ASMs flown under pro-rate arrangements		12%	15.70%	13%
Rental income under operating leases
Operating lease revenue relating to lease payments		$ 48,714	$ 46,532	$ 34,791
Operating lease revenue relating to variable lease payments		17,050	19,998	5,710
Total operating revenues		3,004,925	2,713,491	2,127,106
Future minimum rental income
2023		45,900
2024		45,177
2025		40,207
2026		34,640
2027		34,619
Thereafter		86,182
Total		286,725
Deferred revenue recognized		11,500	6,800
Unbilled revenue recognized		11,491	8,404
Unbilled revenue		19,900
Deferred revenue		144,700	103,900
Deferred revenue in other current liabilities		5,200	24,500
Deferred revenue in other long-term liabilities		139,500	79,400
Property and equipment and related assets		5,548,480	5,498,599
Deferred recognizing revenue		40,812	(6,832)	110,728
Accounts receivable		100,500	65,300
Gross receivables current		122,500
Gross receivables Non-current		210,500
Balance	$ 15,388	41,976	46,225	15,388
Adjustments to credit loss reserves		(4,591)	(4,249)	30,837
Balance		37,385	41,976	46,225
Other Noncurrent Liabilities
Future minimum rental income
Deferred lease revenue		22,100
Other Current Assets
Future minimum rental income
Unbilled revenue		9,900
Other Noncurrent Assets
Future minimum rental income
Unbilled revenue		10,000	8,400
Topic 326
Future minimum rental income
Credit loss	$ 11,600
Capacity Purchase Agreements
Future minimum rental income
Deferred revenue		$ 18,700
United | United Express Agreements
Future minimum rental income
Agreement term		3 years 6 months
United | United Express Prorate Agreement
Future minimum rental income
Notice period for termination of agreement		120 days
Delta
Future minimum rental income
Number of aircraft | aircraft		155
Delta | Delta Connection Prorate Agreement
Future minimum rental income
Notice period for termination of agreement		30 days
Delta | Delta Connection Agreements
Future minimum rental income
Agreement term		5 years 7 months 6 days
American
Future minimum rental income
Number of aircraft | aircraft		100
American | American Capacity Purchase Agreement
Future minimum rental income
Agreement term		4 years 3 months 18 days
Alaska | Alaska Capacity Purchase Agreement
Future minimum rental income
Agreement term		8 years 9 months 18 days
Jet aircraft and spare engines leased to third parties
Future minimum rental income
Property and equipment and related assets		$ 221,000
CRJ 200
Future minimum rental income
Number of seats on aircraft | aircraft		50
CRJ 200 | United | United Express Agreements
Future minimum rental income
Number of aircraft | aircraft		70
CRJ 200 | United | United Express Prorate Agreement
Future minimum rental income
Number of aircraft | aircraft		41
CRJ 200 | Delta | Delta Connection Prorate Agreement
Future minimum rental income
Number of aircraft | aircraft		25
CRJ 700 | Minimum
Future minimum rental income
Number of seats on aircraft | aircraft		65
CRJ 700 | Maximum
Future minimum rental income
Number of seats on aircraft | aircraft		76
CRJ 700 | United | United Express Agreements
Future minimum rental income
Number of aircraft | aircraft		19
CRJ 700 | Delta | Delta Capacity Purchase Agreement
Future minimum rental income
Number of aircraft | aircraft		5
CRJ 700 | American | American Capacity Purchase Agreement
Future minimum rental income
Number of aircraft | aircraft		80
CRJ 900 | Minimum
Future minimum rental income
Number of seats on aircraft | aircraft		65
CRJ 900 | Maximum
Future minimum rental income
Number of seats on aircraft | aircraft		76
CRJ 900 | Delta | Delta Capacity Purchase Agreement
Future minimum rental income
Number of aircraft | aircraft		41
E175 | Minimum
Future minimum rental income
Number of seats on aircraft | aircraft		65
E175 | Maximum
Future minimum rental income
Number of seats on aircraft | aircraft		76
E175 | Sky West Airlines Inc. | Alaska Capacity Purchase Agreement
Future minimum rental income
Number of aircraft under purchase agreement | aircraft		1
E175 | United | United Express Agreements
Future minimum rental income
Number of aircraft | aircraft		90
E175 | Delta | Delta Capacity Purchase Agreement
Future minimum rental income
Number of aircraft | aircraft		84
E175 | American
Future minimum rental income
Number of aircraft | aircraft		3
E175 | American | American Capacity Purchase Agreement
Future minimum rental income
Number of aircraft | aircraft		20
E175 | Alaska
Future minimum rental income
Number of aircraft | aircraft		42
Flying agreements
Rental income under operating leases
Total operating revenues		$ 2,899,837	2,615,076	2,060,801
Future minimum rental income
Accounts receivable		73,700	50,800
Capacity purchase agreements flight operations revenue (non-lease component)
Rental income under operating leases
Total operating revenues		2,028,308	1,678,219	1,265,923
Capacity purchase agreements fixed aircraft lease revenue
Rental income under operating leases
Total operating revenues		504,529	527,173	526,018
Capacity purchase agreements variable aircraft lease revenue
Rental income under operating leases
Total operating revenues		17,664
Prorate agreements revenue
Rental income under operating leases
Total operating revenues		349,336	409,684	268,860
Airport customer service and other revenue
Rental income under operating leases
Total operating revenues		39,324	31,885	25,804
Lease, airport services and other.
Rental income under operating leases
Total operating revenues		$ 105,088	$ 98,415	$ 66,305

Nature of Operations and Sum_12

Nature of Operations and Summary of Significant Accounting Policies - Capacity Purchase Agreements Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Condensed Consolidated Financial Statements
Grant revenue	$ 3,004,925	$ 2,713,491	$ 2,127,106

Nature of Operations and Sum_13

Nature of Operations and Summary of Significant Accounting Policies - Net Income (Loss) Per Share and Fair Value (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) segment $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares
Net Income (Loss) Per Common Share
Number of outstanding units not included in computation of Diluted EPS (in shares)	859,000	78,000	896,000
Numerator:
Net income (loss) | $	$ 72,953	$ 111,910	$ (8,515)
Denominator:
Basic earnings per share weighted average shares (in shares)	50,548,000	50,348,000	50,195,000
Dilution due to employee equity awards and warrants (in shares)	96,000	405,000
Diluted earnings per share weighted average shares	50,644,000	50,753,000	50,195,000
Basic earnings per share (in dollars per share) | $ / shares	$ 1.44	$ 2.22	$ (0.17)
Diluted earnings per share (in dollars per share) | $ / shares	$ 1.44	$ 2.20	$ (0.17)
Fair Value of Financial Instruments
Total long-term debt | $	$ 3,409,311	$ 3,140,938
Segment Reporting
Number of reporting segments | segment	2
Performance Share Units (PSUs)
Net Income (Loss) Per Common Share
Number of outstanding units not included in computation of Diluted EPS (in shares)	146,000	140,000	178,000
Warrants PSP1
Net Income (Loss) Per Common Share
Number of outstanding units not included in computation of Diluted EPS (in shares)	437,000		582,000
Warrants exercise price | $ / shares	$ 28.38
Warrants PSP2
Net Income (Loss) Per Common Share
Number of outstanding units not included in computation of Diluted EPS (in shares)	125,000
Warrants exercise price | $ / shares	$ 40.41
Warrants PSP3
Net Income (Loss) Per Common Share
Number of outstanding units not included in computation of Diluted EPS (in shares)	78,000	78,000
Warrants exercise price | $ / shares	$ 57.47
Employee Stock Option
Net Income (Loss) Per Common Share
Number of outstanding units not included in computation of Diluted EPS (in shares)	219,000		314,000

Recovery from the COVID-19 Pa_3

Recovery from the COVID-19 Pandemic and Labor Impact (Details)	12 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2021 item	Dec. 31, 2020 USD ($) item
Unusual or Infrequent Item, or Both [Line Items]
Proceeds received	$ 260,640,000
Grants received	$ 0
PSP agreement
Unusual or Infrequent Item, or Both [Line Items]
Number of payroll support program agreements | item		3	3
Unsecured term loan | PSP agreement
Unusual or Infrequent Item, or Both [Line Items]
Debt term	10 years
Secured loan
Unusual or Infrequent Item, or Both [Line Items]
Proceeds received	$ 60,000,000
Treasury Loan Agreement
Unusual or Infrequent Item, or Both [Line Items]
Proceeds received			$ 60,000,000

Recovery from the COVID-19 Pa_4

Recovery from the COVID-19 Pandemic and Labor Impact - Amount Received and Warrants Issued (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) shares
Unusual or Infrequent Item, or Both [Line Items]
Total	$ 1,028,800
Grant	768,160
Loan	$ 260,640
Number of Warrants | shares	785,226
Secured loan
Unusual or Infrequent Item, or Both [Line Items]
Total	$ 60,000
Loan	$ 60,000
Number of Warrants | shares	211,416
Warrants PSP1
Unusual or Infrequent Item, or Both [Line Items]
Total	$ 450,701
Grant	345,491
Loan	$ 105,210
Number of Warrants | shares	370,720
Warrants PSP2
Unusual or Infrequent Item, or Both [Line Items]
Total	$ 268,070
Grant	217,649
Loan	$ 50,421
Number of Warrants | shares	124,773
Warrants PSP3
Unusual or Infrequent Item, or Both [Line Items]
Total	$ 250,029
Grant	205,020
Loan	$ 45,009
Number of Warrants | shares	78,317

Segment Reporting (Details)

Segment Reporting (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) segment	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Segment Reporting
Number of reporting segments | segment	2
Operating revenues	$ 3,004,925	$ 2,713,491	$ 2,127,106
Operating expense	2,823,763	2,437,624	2,018,304
Depreciation and amortization expense	394,552	440,198	474,959
Special items - impairment charges		84,592
Interest expense	127,083	123,122	123,173
Segment profit	54,079	152,745	(14,371)
Total assets	7,414,553	7,125,947	6,887,622
Capital expenditures (including non-cash)	662,317	567,037	460,483
SkyWest Airlines
Segment Reporting
Operating revenues	2,492,318	2,192,432	1,636,762
Operating expense	2,525,076	2,177,524	1,716,808
Depreciation and amortization expense	182,475	210,281	221,216
Special items - impairment charges		84,592
Interest expense	12,805	13,360	12,381
Segment profit	(45,563)	1,548	(92,427)
Total assets	2,977,804	2,957,745	2,804,259
Capital expenditures (including non-cash)	82,891	128,712	124,825
SkyWest Leasing
Segment Reporting
Operating revenues	512,607	521,059	490,344
Operating expense	298,687	260,100	301,496
Depreciation and amortization expense	212,077	229,917	253,743
Interest expense	114,278	109,762	110,792
Segment profit	99,642	151,197	78,056
Total assets	4,436,749	4,168,202	4,083,363
Capital expenditures (including non-cash)	$ 579,426	$ 438,325	$ 335,658

Long-term Debt (Details)

Long-term Debt (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) aircraft shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2021 USD ($)
Debt Instrument [Line Items]
Total	$ 3,409,311		$ 3,140,938
Current portion of long-term debt	(442,360)		(395,371)
Long-term portion of unamortized debt issue cost, net	(25,179)		(28,147)
Long-term debt, net of current maturities and debt issue costs	2,941,772		2,717,420
Current portion of long-term debt	442,360		395,371
Current portion of unamortized debt issue cost, net	(3,858)		(3,573)
Current portion of long-term debt, net of debt issue costs	$ 438,502		$ 391,798
Basis spread on variable rate	3.50%
Effective interest rate (as a percent)	4%		3.80%
Warrants to purchase shares | shares	785,226
Loan	$ 260,640
Aggregate amounts of principal maturities of long-term debt
2023	442,360
2024	443,642
2025	527,564
2026	504,269
2027	457,326
Thereafter	1,034,150
Letters of credit	29,900		$ 31,400
Current borrowing capacity	70,100		43,600
Letters of credit and surety bonds outstanding with various banks and surety institutions	$ 59,200		61,400
E175
Debt Instrument [Line Items]
Number of aircraft delivered | aircraft	25
Purchase of aircraft financed through long-term debt	$ 516,600
Minimum
Debt Instrument [Line Items]
Interest rate (as a percent)	3.60%
Minimum | E175
Debt Instrument [Line Items]
Debt instrument, term	5 years
Maximum
Debt Instrument [Line Items]
Interest rate (as a percent)	4.70%
Maximum | E175
Debt Instrument [Line Items]
Debt instrument, term	12 years
Promissory note
Debt Instrument [Line Items]
Principal amount	$ 167,900
Promissory note | Minimum
Debt Instrument [Line Items]
Debt instrument, term	3 years
Promissory note | Maximum
Debt Instrument [Line Items]
Debt instrument, term	4 years
Secured loan
Debt Instrument [Line Items]
Total		$ 60,000
Warrants to purchase shares | shares		211,416
Warrants exercise price | $ / shares		$ 28.38
Warrant term		5 years
Treasury Loan Agreement
Debt Instrument [Line Items]
Loan		$ 60,000
Notes payable to banks, due in quarterly installments, plus interest at 2.33% to 5.95% through 2034, secured by aircraft
Debt Instrument [Line Items]
Total	$ 2,604,058		2,535,827
Notes payable to banks, due in quarterly installments, plus interest at 2.33% to 5.95% through 2034, secured by aircraft | Minimum
Debt Instrument [Line Items]
Interest rate (as a percent)	2.33%
Notes payable to banks, due in quarterly installments, plus interest at 2.33% to 5.95% through 2034, secured by aircraft | Maximum
Debt Instrument [Line Items]
Interest rate (as a percent)	5.95%
Notes payable to banks, due in monthly or semi-annual installments, plus interest at 2.68% to 5.66% through 2032, secured by aircraft and engines
Debt Instrument [Line Items]
Total	$ 604,613		404,471
Notes payable to banks, due in monthly or semi-annual installments, plus interest at 2.68% to 5.66% through 2032, secured by aircraft and engines | Minimum
Debt Instrument [Line Items]
Interest rate (as a percent)	2.68%
Notes payable to banks, due in monthly or semi-annual installments, plus interest at 2.68% to 5.66% through 2032, secured by aircraft and engines | Maximum
Debt Instrument [Line Items]
Interest rate (as a percent)	5.66%
Notes payable to U.S. Government, interest due quarterly at 1.00% through 2025 and based on SOFR plus spread from 2025 through 2031, unsecured
Debt Instrument [Line Items]
Interest rate (as a percent)	1%
Total	$ 200,640		200,640
Primarily related to acquisition of aircraft and certain spare engines
Debt Instrument [Line Items]
Total	3,050,000		2,940,000
Line of credit
Aggregate amounts of principal maturities of long-term debt
Maximum borrowing capacity	100,000		75,000
Amount outstanding	$ 0		$ 0

Long-term Debt - Carrying Value

Long-term Debt - Carrying Value and Fair Value (Details) - Recurring - Level 2 - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Carrying value	$ 3,409,311	$ 3,140,938
Fair value	$ 3,264,704	$ 3,132,072

Income Taxes - Provision (Detai

Income Taxes - Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Current tax provision (benefit):
Federal	$ (7,319)		$ (4,397)
State	1,813	$ 846	(875)
Total current tax provision (benefit)	(5,506)	846	(5,272)
Deferred tax provision (benefit):
Federal	21,587	32,510	6,659
State	3,549	5,344	(199)
Total deferred tax provision (benefit)	25,136	37,854	6,460
Provision for income taxes	$ 19,630	$ 38,700	$ 1,188

Income Taxes - Reconciliation (

Income Taxes - Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statutory Federal income tax rate (as a percent)	21%	21%	21%
Reconciliation
Computed provision (benefit) for income taxes at the statutory rate	$ 19,442	$ 31,628	$ (1,539)
State income tax provision, net of federal income tax benefit	4,295	6,247	173
Non-deductible expenses	546	1,007	2,539
Valuation allowance changes affecting the provision for income taxes	1,716		(892)
Excess tax benefits from share based compensation	534	(92)	(1,434)
Other, net	(6,903)	(90)	2,341
Provision for income taxes	19,630	38,700	1,188
Deferred tax assets:
Accrued benefits	29,154	21,401
Net operating loss carryforward	186,517	175,659
Aircraft credits	77,962	22,265
Deferred revenue	35,385	25,405
Operating lease liabilities	39,209	57,991
Interest deduction limitation	26,469
Accrued reserves and other	49,972	31,431
Total deferred tax assets	444,668	334,152
Valuation allowance	(1,716)
Deferred tax liabilities:
Accelerated depreciation	(1,094,538)	(940,867)
Operating lease right-of-use assets	(35,474)	(56,521)
Total deferred tax liabilities	(1,130,012)	(997,388)
Net deferred tax liability	(687,060)	(663,236)
Accounting Standards Update 2016-09
Reconciliation
Benefit (expense) from share-based compensation	(500)	$ 100	1,400
ExpressJet | State and Local Jurisdiction
Reconciliation
Valuation allowance	$ 1,700		$ 900

Income Taxes - Net Operating Lo

Income Taxes - Net Operating Losses and Tax Rates (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net operating losses
Tax benefit for release of uncertain tax position	$ 7.3
Statutory Federal income tax rate (as a percent)	21%	21%	21%
Domestic Tax Authority
Net operating losses
Operating loss carryforward	$ 817.4	$ 745.8
Estimated effective tax rate on net operating losses	21%
State and Local Jurisdiction
Net operating losses
Operating loss carryforward	$ 380.6	$ 554.7
Estimated effective tax rate on net operating losses	3.45%

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Taxes
Unrecognized tax benefits at the beginning of year	$ 15,529,000	$ 14,980,000	$ 14,620,000
Gross increases - prior year tax positions	343,000	549,000	360,000
Gross decreases - prior year tax positions	(7,662,000)
Unrecognized tax benefits at end of year	8,210,000	15,529,000	14,980,000
Interest and penalties in year-end balance	607,000	976,000	427,000
Interest expense related to uncertain tax positions	$ 343,000	$ 549,000	$ 360,000

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) employee aircraft	Dec. 31, 2021 USD ($)	Dec. 31, 2020
Concentration Risk and Significant Customers
Accrued workers' compensation liability | $	$ 21.6	$ 17.5
Accrued workers' compensation liability, current | $	$ 8	$ 7.1
E175
Concentration Risk and Significant Customers
Commitment to purchase number of aircraft | aircraft	2
Revenue from rights, concentration risk | Customer Concentration Risk | Delta, United, and Continental Combined
Concentration Risk and Significant Customers
Concentration risk (as a percent)	72.50%	73.50%	76.40%
Full-time equivalent number of employees | Labor Force Concentration Risk
Concentration Risk and Significant Customers
Number of employees | employee	13,582
SkyWest Airlines | Full-time equivalent number of employees | Unionized employees
Concentration Risk and Significant Customers
Approximate number of active employees | employee	0

Commitments and Contingencies -

Commitments and Contingencies - Guarantees (Details) $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($)
Other income, net
Leases, Commitments, Guarantees and Contingencies
Guaranteed amount received as consideration, percentage	6.50%
Debt | Aircraft and engines
Leases, Commitments, Guarantees and Contingencies
Guaranteed amount	$ 19.8
Term of guarantee obligations	5 years

Leases (Details)

Leases (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) aircraft	Dec. 31, 2021 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets	$ 151,928	$ 238,516
Current maturities of lease liabilities	71,726	78,886
Noncurrent operating leases	88,622	158,274
Operating leases	77,900
Accelerated lease expense	$ 11,400
Weighted-average remaining lease term for operating leases	6 years 6 months
Weighted-average discount rate for operating leases	6.10%
Lease costs
Operating lease cost	$ 97,998	89,891
Variable and short-term lease cost	1,830	4,468
Sublease income	(7,089)	(6,552)
Total lease cost	$ 92,739	$ 87,807
Aircraft
Lessee, Lease, Description [Line Items]
Number of aircraft acquired | aircraft	43
Aircraft | Minimum
Lessee, Lease, Description [Line Items]
Remaining lease term	1 year
Aircraft | Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term	8 years
Airport Facilities | Minimum
Lessee, Lease, Description [Line Items]
Remaining lease term	1 month
Airport Facilities | Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term	34 years

Leases - Operating Leases (Deta

Leases - Operating Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Future minimum rental payments required under operating leases
2023	$ 74,557
2024	32,525
2025	15,837
2026	13,427
2027	12,291
Thereafter	54,298
Total	202,935
Total rental expense for non-cancelable aircraft operating leases	75,400	$ 63,400	$ 65,300
Minimum rental expense for airport station rents	$ 13,200	$ 17,200	$ 20,100

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Fair Value Measurements
Marketable Securities	$ 944,231	$ 601,989
Recurring | Estimate of Fair Value Measurement
Fair Value Measurements
Marketable Securities	944,231	601,989
Investments in Other Companies	21,380
Cash and Cash Equivalents	102,984	258,421
Total Assets Measured at Fair Value	1,068,595	860,410
Recurring | Estimate of Fair Value Measurement | Corporate Bond Securities
Fair Value Measurements
Marketable Securities	624,254	54,673
Recurring | Estimate of Fair Value Measurement | Commercial Paper
Fair Value Measurements
Marketable Securities	319,977	547,316
Recurring | Level 1
Fair Value Measurements
Investments in Other Companies	7,200
Cash and Cash Equivalents	102,984	258,421
Total Assets Measured at Fair Value	110,184	258,421
Recurring | Level 2
Fair Value Measurements
Marketable Securities	944,231	601,989
Total Assets Measured at Fair Value	944,231	601,989
Recurring | Level 2 | Corporate Bond Securities
Fair Value Measurements
Marketable Securities	624,254	54,673
Recurring | Level 2 | Commercial Paper
Fair Value Measurements
Marketable Securities	319,977	$ 547,316
Recurring | Level 3
Fair Value Measurements
Investments in Other Companies	14,180
Total Assets Measured at Fair Value	$ 14,180

Assets Held for Sale (Details)

Assets Held for Sale (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) aircraft
Assets Held for Sale
Number of aircraft held-for-sale | aircraft	14
Impairment loss of assets held for sale	$ 51,384
CRJ 700 | Held for sale
Assets Held for Sale
Number of aircraft held-for-sale | aircraft	14
Assets held for sale	$ 56,700
Impairment loss of assets held for sale	$ 51,400

Special Items (Details)

Special Items (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)
CRJ 900
Impairment charges	$ 84.6

Capital Transactions - Preferre

Capital Transactions - Preferred Stock (Details) - shares	Dec. 31, 2022	Dec. 31, 2021
Preferred Stock
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock outstanding (in shares)	0

Capital Transactions - Stock Co

Capital Transactions - Stock Compensation (Details)	12 Months Ended
	Dec. 31, 2022 USD ($) item $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	May 07, 2019 shares
Share-Based Compensation
Options outstanding (in shares)	6,816	16,633	57,653
Performance period	90 days
Compensation expenses
Stock based compensation expense | $	$ 9,159,000	$ 8,685,000	$ 6,802,000
Number of Options
Outstanding at the beginning of the period (in shares)	16,633	57,653	60,231
Exercised (in shares)	(9,817)	(41,020)	(2,578)
Outstanding at the end of the period (in shares)	6,816	16,633	57,653
Exercisable (in shares)	6,816	16,633
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share) | $ / shares	$ 14.62	$ 14.74	$ 14.74
Exercised (in dollars per share) | $ / shares	14.52	14.78	14.78
Outstanding at the end of the period (in dollars per share) | $ / shares	14.78	14.62	$ 14.74
Exercisable (in dollars per share) | $ / shares	$ 14.78	$ 14.62
Weighted Average Remaining Contractual Term
Outstanding, Weighted Average Remaining Contractual Term (in years)	1 month 6 days	1 year
Exercisable, Weighted Average Remaining Contractual Term (in years)	1 month 6 days	1 year
Aggregate Intrinsic Value
Average intrinsic value of shares outstanding | $	$ 11,800	$ 410,400
Average intrinsic value of shares exercisable | $	$ 11,800	$ 410,400
Director
Share-Based Compensation
Granted (in shares)	24,423	21,175	14,643
Granted (in dollars per share) | $ / shares	$ 32.86	$ 44.87	$ 61.45
Number of shares
Granted (in shares)	24,423	21,175	14,643
Weighted Average Grant-Date Fair Value
Granted (in dollars per share) | $ / shares	$ 32.86	$ 44.87	$ 61.45
Restricted stock grants and performance share units
Compensation expenses
Total unrecognized compensation cost | $	$ 18,500,000
Unrecognized compensation cost recognized over a weighted average period (in years)	1 month 27 days
Employee Stock Option
Compensation expenses
Period from grant date after which stock options become exercisable, minimum (in months)	6 months
Period from grant date within which incentive stock options are exercisable, maximum (in years)	7 years
Aggregate Intrinsic Value
Total intrinsic value of options exercised | $	$ 100,000	$ 1,800,000	$ 100,000
Performance Share Units (PSUs)
Share-Based Compensation
Granted (in shares)	225,345	157,210	69,132
Vesting period	3 years
Granted (in dollars per share) | $ / shares	$ 32.73	$ 44.87	$ 61.45
Number of performance period | item	3
Performance period	1 year
Award percentage	40%
Number of shares
Nonvested shares at the beginning of the period (in shares)	292,792	196,609	233,571
Granted (in shares)	225,345	157,210	69,132
Additional PSUs awarded from the 2017 grant			83,042
Forfeited (in shares)	(45,695)	(11,392)
Vested (in shares)	(30,480)	(45,644)	(166,084)
Cancelled (in shares)	(13,032)	(3,991)	(23,052)
Nonvested shares at the end of the period (in shares)	428,930	292,792	196,609
Weighted Average Grant-Date Fair Value
Nonvested shares at the beginning of the period (in dollars per share) | $ / shares	$ 49.39	$ 54.17	$ 45.44
Granted (in dollars per share) | $ / shares	32.73	44.87	61.45
Additional PSUs awarded from the 2017 grant (in dollars per share) | $ / shares			35.81
Forfeiture (in dollars per share) | $ / shares	48.87	53.41
Vested (in dollars per share) | $ / shares	48.87	53.41	35.81
Cancelled (in dollars per share) | $ / shares	41.81	53.30	53.66
Nonvested shares at the end of the period (in dollars per share) | $ / shares	$ 40.96	$ 49.39	$ 54.17
Performance Share Units (PSUs) | Maximum
Share-Based Compensation
Award percentage	250%	250%	200%
Performance Share Units (PSUs) | Minimum
Share-Based Compensation
Award percentage	0%	0%	0%
Restricted Stock Units (RSUs)
Share-Based Compensation
Granted (in shares)	66,680	44,770	82,505
Granted (in dollars per share) | $ / shares	$ 32.86	$ 44.87	$ 61.45
Number of shares
Nonvested shares at the beginning of the period (in shares)	200,173	237,977	284,686
Granted (in shares)	66,680	44,770	82,505
Vested (in shares)	(86,534)	(69,184)	(103,231)
Cancelled (in shares)	(20,297)	(13,390)	(25,983)
Nonvested shares at the end of the period (in shares)	160,022	200,173	237,977
Weighted Average Grant-Date Fair Value
Nonvested shares at the beginning of the period (in dollars per share) | $ / shares	$ 52.45	$ 54.15	$ 45.21
Granted (in dollars per share) | $ / shares	32.86	44.87	61.45
Vested (in dollars per share) | $ / shares	48.69	53.41	35.81
Cancelled (in dollars per share) | $ / shares	44.91	52.28	52.31
Nonvested shares at the end of the period (in dollars per share) | $ / shares	$ 47.28	$ 52.45	$ 54.15
Long Term Incentive Plan 2019
Share-Based Compensation
Number of shares authorized				4,500,000
Shares remaining available for future issuance	2,800,000
Long Term Incentive Plan 2019 | Restricted Stock Units (RSUs)
Share-Based Compensation
Granted (in shares)	66,680
Vesting period	3 years
Granted (in dollars per share) | $ / shares	$ 32.86
Number of shares
Granted (in shares)	66,680
Weighted Average Grant-Date Fair Value
Granted (in dollars per share) | $ / shares	$ 32.86

Capital Transactions - Informat

Capital Transactions - Information About Stock Options Outstanding (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Options Exercisable
Warrants to purchase shares	785,226
Borrowed amount	$ 3,409,311,000	$ 3,140,938,000
$14.00 to $15.00
Stock options, exercise price
Exercise price range, low end of range (in dollars per share)	$ 14
Exercise price range, high end of range (in dollars per share)	$ 15
Options Outstanding
Number of options outstanding (in shares)	6,816
Options outstanding, Weighted Average Remaining Contractual Life	1 month 6 days
Options Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 14.78
Options Exercisable
Number of options Exercisable (in shares)	6,816
Options Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 14.78
Warrants PSP1
Options Exercisable
Warrants to purchase shares	370,720
Warrants PSP2
Options Exercisable
Warrants to purchase shares	124,773
Warrants PSP3
Options Exercisable
Warrants to purchase shares	78,317
PSP agreement | Warrant Shares
Options Exercisable
Warrants to purchase shares		203,090	370,720
Warrants exercise price			$ 28.38
Warrant term		5 years	5 years
Weighted average fair value of the warrants			$ 13.57
PSP agreement | Warrants PSP1
Options Exercisable
Warrants to purchase shares		124,773
Warrants exercise price		$ 40.41
Warrants Outstanding		124,773
PSP agreement | Warrants PSP3
Options Exercisable
Warrants to purchase shares		78,317
Warrants exercise price		$ 57.47
Warrants Outstanding		78,317
Secured loan
Options Exercisable
Warrants to purchase shares			211,416
Borrowed amount			$ 60,000,000
Warrants exercise price			$ 28.38
Warrant term			5 years
Weighted average fair value of the warrants			$ 15.22
Minimum | PSP agreement | Warrants PSP1
Options Exercisable
Warrants exercise price		$ 32.52
Minimum | PSP agreement | Warrants PSP3
Options Exercisable
Warrants exercise price		$ 22.31

Retirement Plans and Employee_3

Retirement Plans and Employee Stock Purchase Plans - Retirement Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Retirement Plans
Maximum benefit plan percentage of participants compensation eligible for employer matching contribution based on position and years of service	12%
SkyWest Plan
Retirement Plans
Required age for an employee to be eligible to participate in plan	18 years
Percentage of employer matching contribution based on length of service	100%
Minimum benefit plan percentage of participants compensation eligible for employer matching contribution based on position and years of service	2%
Maximum benefit plan percentage of participants compensation eligible for employer matching contribution based on position and years of service	12%
Company's combined contributions	$ 45.4	$ 42.1	$ 31.9

Retirement Plans and Employee_4

Retirement Plans and Employee Stock Purchase Plans - Employee Stock Purchase Plans (Details) - USD ($) $ / shares in Units, shares in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Employee Stock Purchase Plans
Service period required to be completed for an employee to be eligible to participate in plan, minimum	90 days
Ownership interest in Company common stock to disqualify employee from participation in plan, maximum (as a percent)	5%
Maximum percentage of base salary which can be contributed by the employees	15%
Maximum amount of base salary which can be contributed annually by the employees	$ 25,000
Discount rate at which common stock can be purchased by the plan participant (as a percent)	5%
Summary of purchases made under the 2010 and 1995 Employee Stock Purchase Plans
Number of shares purchased	105,606	63,962	65,512
Average price of shares purchased (in dollars per share)	$ 26.66	$ 39.70	$ 42.45
2009 Stock Purchase Plan
Summary of purchases made under the 2010 and 1995 Employee Stock Purchase Plans
Stock based compensation expense	$ 0	$ 0	$ 0

Stock Repurchase (Details)

Stock Repurchase (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Stock Repurchase
Common stock authorized for repurchase, maximum (in shares)	250
Common stock remaining number of shares authorized to repurchase	139.6
Stock repurchased (shares)			0.4
Stock repurchased during period (value)			$ 20
Weighted average price per share of common stock (in dollars per share)			$ 51.87
Payment of income tax obligation on employee equity awards	$ 1.2	$ 1.6	$ 6.2

Investments in Other Companie_2

Investments in Other Companies (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) aircraft	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Warrants to purchase shares | shares	785,226
Eve UAM, LLC | Strategic partnership | Electric vertical takeoff and landing ("eVTOL") aircraft
Non-binding letter of intent to purchase number of aircraft | aircraft		100
Aero Engines, LLC. ("Aero Engines")
Payments to acquire interest in joint venture				$ 22,300
Investment ownership (as a percent)	75%			75%
Additional interest in Joint venture	$ 3,300		$ 1,000
Long-term debt	0
Investment balance in other companies	26,600
Aero Engines, LLC. ("Aero Engines") | Other Nonoperating Income.
Company's portion of loss generated by other companies	$ 1,400
Eve Holdings, Inc. ("Eve")
Warrants to purchase shares | shares	1,500,000
Warrants exercise price (in dollars per share) | $ / shares	$ 0.01
Initial investment	$ 10,000
Eve Holdings, Inc. ("Eve") | Level 3
Beginning balance
Purchases	6,551
Unrealized gains	$ 7,629
Fair Value, Net Derivative Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)
Ending balance	$ 14,180
Eve Holdings, Inc. ("Eve") | Level 3 | Black Scholes Option Pricing Model | Volatility
Measurement input	0.49
Eve Holdings, Inc. ("Eve") | Put option
Shares obtained | shares	1,000,000
Eve Holdings, Inc. ("Eve") | Other Assets
Investment balance in other companies	$ 21,400
Eve Holdings, Inc. ("Eve") | Other Nonoperating Income.
Company's portion of loss generated by other companies	$ 11,400
Eve Holdings, Inc. ("Eve") | Class A common stock
Number of shares acquired | shares	1,000,000

SCHEDULE II - VALUATION AND Q_2

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
VALUATION AND QUALIFYING ACCOUNTS
Balance at Beginning of Year	$ 64,932	$ 65,901
Additions Charged to Costs and Expenses	1,250	3,280
Deductions	(4,591)
Balance at End of Year	61,591	64,932	$ 65,901
Topic 326
VALUATION AND QUALIFYING ACCOUNTS
Balance at Beginning of Year		65,901	31,296
Additions Charged to Costs and Expenses			34,623
Deductions			(18)
Balance at End of Year			65,901
Inventory Valuation and Obsolescence
VALUATION AND QUALIFYING ACCOUNTS
Balance at Beginning of Year	22,956	19,676	15,890
Additions Charged to Costs and Expenses	1,250	3,280	3,786
Balance at End of Year	24,206	22,956	19,676
Allowance for doubtful accounts receivable
VALUATION AND QUALIFYING ACCOUNTS
Balance at Beginning of Year	41,976	46,225	18
Deductions	(4,591)	(4,249)	(18)
Balance at End of Year	$ 37,385	41,976	46,225
Allowance for doubtful accounts receivable | Topic 326
VALUATION AND QUALIFYING ACCOUNTS
Balance at Beginning of Year		$ 46,225	15,388
Additions Charged to Costs and Expenses			30,837
Balance at End of Year			$ 46,225