Atlas Air Worldwide (AAWW) 10-K 22 Feb 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Feb. 16, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Document period end date	Dec. 31, 2017
Amendment flag	false
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2,017
Current fiscal year end date	--12-31
Entity central index key	1,135,185
Entity current reporting status	Yes
Entity filer category	Large Accelerated Filer
Entity registrant name	ATLAS AIR WORLDWIDE HOLDINGS INC
Entity trading symbol	AAWW
Entity voluntary filers	No
Entity well known seasoned issuer	Yes
Entity public float			$ 1,138
Entity common stock shares outstanding		25,434,788

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current Assets
Cash and cash equivalents	$ 280,809	$ 123,890
Short-term investments	13,604	4,313
Restricted cash	11,055	14,360
Accounts receivable, net of allowance	194,478	166,486
Prepaid maintenance	13,346	4,418
Prepaid expenses and other current assets	74,294	44,603
Total current assets	587,586	358,070
Property and Equipment
Flight equipment	4,447,097	3,886,714
Ground equipment	70,951	68,688
Less: accumulated depreciation	(701,249)	(568,946)
Flight equipment modifications in progress	186,302	154,226
Property and equipment, net	4,003,101	3,540,682
Other Assets
Long-term investments and accrued interest	15,371	27,951
Deferred costs and other assets	242,919	204,647
Intangible assets, net and goodwill	106,485	116,029
Total Assets	4,955,462	4,247,379
Current Liabilities
Accounts payable	65,740	59,543
Accrued liabilities	454,843	320,887
Current portion of long-term debt and capital lease	218,013	184,748
Total current liabilities	738,596	565,178
Other Liabilities
Long-term debt and capital lease	2,008,986	1,666,663
Deferred taxes	214,694	298,165
Financial instruments and other liabilities	203,330	200,035
Total other liabilities	2,427,010	2,164,863
Commitments and contingencies	0	0
Stockholders’ Equity
Preferred stock	0	0
Common stock	301	296
Additional paid-in-capital	715,735	657,082
Treasury stock, at cost	(193,732)	(183,119)
Accumulated other comprehensive loss	(3,993)	(4,993)
Retained earnings	1,271,545	1,048,072
Total stockholders’ equity	1,789,856	1,517,338
Total Liabilities and Equity	$ 4,955,462	$ 4,247,379

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts receivable	$ 1,494	$ 997
Preferred stock par value	$ 1	$ 1
Preferred stock shares authorized	10,000,000	10,000,000
Preferred stock shares issued	0	0
Common stock par value	$ 0.01	$ 0.01
Common stock shares authorized	100,000,000	100,000,000
Common stock shares issued	30,104,648	29,633,605
Common stock shares outstanding	25,292,454	25,017,242
Treasury stock shares	4,812,194	4,616,363

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Operating Revenue	$ 2,156,460	$ 1,839,627	$ 1,822,659
Operating Expenses
Salaries, wages and benefits	456,075	424,332	351,372
Aircraft fuel	333,046	275,113	333,390
Maintenance, materials and repairs	273,676	206,106	202,337
Depreciation and amortization	166,713	148,876	128,740
Travel	144,699	127,748	102,755
Aircraft rent	142,945	146,110	145,031
Navigation fees, landing fees and other rent	116,318	78,441	99,345
Passenger and ground handling services	107,787	89,657	83,185
Loss (gain) on disposal of aircraft	(31)	(11)	1,538
Special charge	106	10,140	17,388
Transaction-related expenses	4,509	22,071	0
Other	168,643	142,733	234,073
Total Operating Expenses	1,914,486	1,671,316	1,699,154
Operating Income	241,974	168,311	123,505
Non-operating Expenses (Income)
Interest income	(6,009)	(5,532)	(12,554)
Interest expense	99,687	84,650	96,756
Capitalized interest	(7,389)	(3,313)	(1,027)
Loss on early extinguishment of debt	167	132	69,728
Unrealized loss on financial instruments	12,533	2,888	0
Gain on investments	0	0	(13,439)
Other (income) expense	(387)	70	1,261
Total Non-operating Expenses (Income)	98,602	78,895	140,725
Income (loss) from continuing operations before income taxes	143,372	89,416	(17,220)
Income tax (benefit) expense	(80,966)	46,791	(24,506)
Income from continuing operations, net of taxes	224,338	42,625	7,286
Loss from discontinued operations, net of taxes	(865)	(1,109)	0
Net Income	$ 223,473	$ 41,516	$ 7,286
Earnings per share from continuing operations:
Basic	$ 8.89	$ 1.72	$ 0.29
Diluted	8.68	1.70	0.29
Loss per share from discontinued operations:
Basic	(0.03)	(0.04)	0
Diluted	(0.03)	(0.04)	0
Earnings per share:
Basic	8.85	1.67	0.29
Diluted	$ 8.64	$ 1.65	$ 0.29
Weighted average shares:
Basic	25,241	24,843	24,833
Diluted	25,854	25,120	25,018

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net Income	$ 223,473	$ 41,516	$ 7,286
Interest rate derivatives:
Reclassification to interest expense	1,621	1,770	6,129
Income tax expense	(621)	(700)	(2,277)
Foreign currency translation:
Translation adjustment	0	0	(343)
Other comprehensive income	1,000	1,070	3,509
Comprehensive Income	$ 224,473	$ 42,586	$ 10,795

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Activities:
Income from continuing operations, net of taxes	$ 224,338	$ 42,625	$ 7,286
Less: Loss from discontinued operations, net of taxes	(865)	(1,109)	0
Net Income	223,473	41,516	7,286
Adjustments to reconcile Net Income to net cash provided by operating activities:
Depreciation and amortization	197,463	168,721	147,604
Accretion of debt securities discount	(1,172)	(1,277)	(4,651)
Provision for allowance for doubtful accounts	198	508	171
Special charge, net of cash payments	106	10,140	16,351
Loss on early extinguishment of debt	167	132	69,728
Unrealized loss on financial instruments	12,533	2,888	0
Loss (gain) on disposal of aircraft	(31)	(11)	1,538
Deferred taxes	(81,330)	47,381	(25,898)
Stock-based compensation	22,319	32,724	16,181
Changes in:
Accounts receivable	(33,201)	22,974	2,016
Prepaid expenses, current assets and other assets	(67,341)	(29,455)	23,171
Accounts payable and accrued liabilities	58,535	(64,059)	119,390
Net cash provided by operating activities	331,719	232,182	372,887
Investing Activities:
Capital expenditures	(87,555)	(46,717)	(45,040)
Payments for flight equipment and modifications	(458,464)	(316,993)	(227,048)
Acquisition of business, net of cash acquired	0	(105,392)	0
Proceeds from investments	4,462	11,714	80,302
Proceeds from disposal of aircraft	0	0	25,441
Net cash used for investing activities	(541,557)	(457,388)	(166,345)
Financing Activities:
Proceeds from debt issuance	620,568	103,492	568,033
Payment of debt issuance costs	(14,664)	(4,034)	(14,509)
Payments of debt	(207,093)	(179,153)	(568,923)
Proceeds from revolving credit facility	150,000	0	0
Payment of revolving credit facility	(150,000)	0	0
Customer maintenance reserves and deposits received	25,784	15,105	16,148
Customer maintenance reserves paid	(18,538)	0	(3,801)
Proceeds from sale of convertible note warrants	38,148	0	36,290
Payments for convertible note hedges	(70,140)	0	(52,903)
Proceeds from stock option exercises	0	0	1,193
Purchase of treasury stock	(10,613)	(11,275)	(26,522)
Excess tax benefit from stock-based compensation	0	390	555
Payment of debt extinguishment costs	0	0	(36,054)
Net cash provided by (used for) financing activities	363,452	(75,475)	(80,493)
Net increase (decrease) in cash, cash equivalents and restricted cash	153,614	(300,681)	126,049
Cash, cash equivalents and restricted cash at the beginning of period	138,250	438,931	312,882
Cash, cash equivalents and restricted cash at the end of period	291,864	138,250	438,931
Noncash Investing and Financing Activities:
Acquisition of flight equipment included in Accounts payable and accrued liabilities	68,732	14,345	33,294
Acquisition of flight equipment under capital lease	$ 30,419	$ 10,800	$ 0

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]
Beginning Balance at Dec. 31, 2014	$ 1,417,795	$ 286	$ (145,322)	$ 573,133	$ (9,572)	$ 999,270
Net Income	7,286					7,286
Other comprehensive income	3,509				3,509
Stock-based compensation	16,181			16,181
Purchase of shares of treasury stock	(26,522)		(26,522)
Exercise of employee stock options	1,193			1,193
Issuance of shares of restricted stock		4		(4)
Equity component of convertible notes, net of tax	32,234			32,234
Purchase of convertible note hedges, net of tax	(33,837)			(33,837)
Issuance of warrants	36,290			36,290
Tax benefit (expense) on restricted stock	54			54
Ending Balance at Dec. 31, 2015	1,454,183	290	(171,844)	625,244	(6,063)	1,006,556
Net Income	41,516					41,516
Other comprehensive income	1,070				1,070
Stock-based compensation	32,724			32,724
Purchase of shares of treasury stock	(11,275)		(11,275)
Issuance of shares of restricted stock		6		(6)
Tax benefit (expense) on restricted stock	(880)			(880)
Ending Balance at Dec. 31, 2016	1,517,338	296	(183,119)	657,082	(4,993)	1,048,072
Net Income	223,473					223,473
Other comprehensive income	1,000				1,000
Stock-based compensation	22,319			22,319
Purchase of shares of treasury stock	(10,613)		(10,613)
Issuance of shares of restricted stock		5		(5)
Equity component of convertible notes, net of tax	43,256			43,256
Purchase of convertible note hedges, net of tax	(45,065)			(45,065)
Issuance of warrants	38,148			38,148
Ending Balance at Dec. 31, 2017	$ 1,789,856	$ 301	$ (193,732)	$ 715,735	$ (3,993)	$ 1,271,545

Consolidated Statements of Sto8

Consolidated Statements of Stockholders' Equity (Parentheticals) - shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement Of Stockholders Equity [Abstract]
Purchase of shares of treasury stock	195,831	297,569	565,352
Exercise of employee stock options	0		25,373
Issuance of shares of restricted stock	471,043	678,160	368,912

Basis of Presentation

Basis of Presentation	12 Months Ended
	Dec. 31, 2017
Basis Of Presentation [Abstract]
Basis of Presentation	1. Basis of Presentation Our consolidated financial statements include the accounts of the holding company, Atlas Air Worldwide Holdings, Inc. (“AAWW”), and its consolidated subsidiaries. AAWW is the parent company of Atlas Air, Inc. (“Atlas”) and Southern Air Holdings, Inc. (“Southern Air”). Southern Air was acquired on April 7, 2016 (see Note 4). AAWW is also the parent company of several subsidiaries related to our dry leasing services (collectively referred to as “Titan”). AAWW has a 51% equity interest and 75% voting interest in Polar Air Cargo Worldwide, Inc. (“Polar”). We record our share of Polar’s results under the equity method of accounting. Intercompany accounts and transactions have been eliminated. We account for investments in entities under the equity method of accounting when we hold between 20% and 50% ownership in the entity and exercise significant influence or when we are not the primary beneficiary of a variable interest entity. “we,” “us,” “our,” and the “Company” mean AAWW and all entities included in its consolidated financial statements. We provide outsourced aircraft and aviation operating services throughout the world, serving Africa, Asia, Australia, Europe, the Middle East, North America and South America through: (i) contractual service arrangements, including those through which we provide aircraft to customers and value-added services, including crew, maintenance and insurance (“ACMI”), as well as those through which we provide crew, maintenance and insurance, but not the aircraft (“CMI”); (ii) cargo and passenger charter services (“Charter”); and (iii) dry leasing aircraft and engines (“Dry Leasing” or “Dry Lease”). Except for per share data, all dollar amounts are in thousands unless otherwise noted.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires us to make estimates and judgments that affect the amounts reported in these financial statements and the related disclosures. Actual results may differ from those estimates. Estimates are used in determining, among other items, asset lives and residual values, cash flows for impairment analysis, heavy maintenance costs, income tax accounting, business combinations, intangible assets, warrants, Revenue Recognition Revenue from ACMI and CMI contracts is typically recognized as the block hours are operated on behalf of a customer during a given month, as defined contractually, based on flight departure. The time interval between when an aircraft departs the terminal until it arrives at the destination terminal is measured in hours and called a “Block Hour”. If a customer flies below a minimum contracted Block Hour guarantee, the contracted minimum revenue amounts are recognized as revenue. We recognize revenue for Charter upon flight departure. We record Dry Lease rental income on a straight-line basis over the term of the operating lease. In limited cases, leases provide for additional rentals based on usage, which is recorded as revenue as it is earned under the terms of the lease. Usage is calculated based on hourly usage or number of flights operated, depending on the lease agreement, and is typically reported monthly by the lessee. Customer maintenance reserves are amounts received under our Dry Leases that are subject to reimbursement to the lessee upon the completion of qualifying maintenance work on the specific Dry Leased aircraft and are included in Accrued liabilities. We defer revenue recognition until the end of the lease, when we are able to finalize the amount, if any, to be reimbursed to the customer. The Company recognizes revenue for management and administrative support services when the services are provided. Cash and Cash Equivalents Cash and cash equivalents include cash on hand, demand deposits and other cash investments that are highly liquid in nature and have original maturities of three months or less at acquisition. Short-term Investments Short-term investments are primarily comprised of certificates of deposit, current portions of debt securities and money market funds. Restricted Cash Cash that is restricted under secured aircraft debt agreements, whereby it can only be used to make principal and interest payments on the related debt secured by those aircraft, is classified as Restricted cash. Accounts Receivable We perform a monthly evaluation of our accounts receivable and establish an allowance for doubtful accounts based on our best estimate of probable credit losses resulting from the inability or unwillingness of our customers to make required payments. Account balances are charged off against the allowance when we determine that the receivable will not be recovered. Escrow Deposits and Letters of Credit We had $5.1 million as of December 31, 2017 and $5.0 million as of December 31, 2016, for certain deposits required in the normal course of business for various items including, but not limited to, surety and customs bonds, airfield privileges, judicial deposits, insurance and cash pledged under standby letters of credit related to collateral. These amounts are included in Deferred costs and other assets. Expendable Parts Expendable parts, materials and supplies for flight equipment are carried at average acquisition costs and are included in Prepaid expenses and other current assets. When used in operations, they are charged to maintenance expense. Allowances for excess and obsolescence for expendable parts expected to be on hand at the date aircraft are retired from service are provided over the estimated useful lives of the related airframes and engines. These allowances are based on management estimates, which are subject to change as conditions in the business evolve. The net book value of expendable parts inventory was $34.7 million as of December 31, 2017 and $24.2 million at December 31, 2016, net of allowances for obsolescence of $27.8 million at December 31, 2017 and $22.3 million at December 31, 2016. Property and Equipment We record property and equipment at cost and depreciate these assets to their estimated residual values on a straight-line basis over their estimated useful lives or average remaining fleet lives. We review these assumptions at least annually and adjust depreciation on a prospective basis. Expenditures for major additions, improvements and flight equipment modifications are generally capitalized and depreciated over the shorter of the estimated life of the improvement, the modified assets’ remaining life or remaining lease term. Most of our flight equipment is specifically pledged as collateral for our indebtedness. The estimated useful lives of our property and equipment are as follows: Range Flight equipment 30 to 40 years Computer software and equipment 3 to 5 years Ground handling equipment and other 3 to 5 years Depreciation expense related to property and equipment was $153.1 million in 2017, $141.5 million in 2016 and $122.2 million in 2015. The net book value of flight equipment on dry lease to customers was $1,270.7 million as of December 31, 2017 and $936.0 million as of December 31, 2016. The accumulated depreciation for flight equipment on dry lease to customers was $152.7 million as of December 31, 2017 and $99.8 million as of December 31, 2016. Rotable parts are recorded in Property and equipment, net, and are depreciated over their average remaining fleet lives and written off when they are determined to be beyond economic repair. The net book value of rotable parts inventory was $184.8 million as of December 31, 2017 and $142.7 million as of December 31, 2016. Capitalized Interest on Flight Equipment Modifications in Progress Interest on funds used to finance the acquisition of flight equipment up to the date the asset is ready for its intended use is capitalized and included in the cost of the asset. Included in capitalized interest is the interest paid on the purchase deposit borrowings directly associated with the acquisition of flight equipment. The remainder of capitalized interest recorded on the acquisition of flight equipment is determined by taking the weighted average cost of funds associated with our other debt and applying it against the amounts paid as purchase deposits. Goodwill Goodwill represents the excess of an acquisition’s purchase price over the fair value of the identifiable net assets acquired and liabilities assumed. Goodwill is not amortized, but tested for impairment annually during the fourth quarter of each year, or more frequently if certain events or circumstances indicate that an impairment loss may have been incurred. Goodwill is not deductible for tax purposes. We may elect to perform a qualitative analysis on the reporting unit that has goodwill to determine whether it is more likely than not that fair value of the reporting unit is less than its carrying value. If the qualitative analysis indicates that it is more likely than not that the fair value of a reporting unit is less than its carrying amount, or if we elect not to perform a qualitative analysis, we perform a quantitative analysis to determine whether a goodwill impairment exists. If the goodwill’s carrying value exceeds its implied fair value calculated using the quantitative approach, an impairment charge is recorded for the difference. Fair value is determined using a discounted cash flow analysis based on key assumptions including, but not limited to, (i) a projection of revenues, expenses and other cash flows; (ii) terminal period revenue growth and cash flows; and (iii) an assumed discount rate. The total amount of goodwill was $40.4 million, which is included in Intangible assets, net and goodwill in the consolidated balance sheets as of December 31, 2017 and 2016 (see Notes 4 and 6). During the fourth quarter of 2017, we performed a qualitative analysis and determined that goodwill was not impaired. Impairment of Long-Lived Assets We record impairment charges on long-lived assets when events and circumstances indicate that the assets may be impaired, the undiscounted cash flows estimated to be generated by those assets are less than the associated carrying amount and the net book value of the assets exceeds the associated estimated fair value. For flight equipment and finite-lived intangibles used in our ACMI and Charter segments, assets are grouped at the operating fleet level for impairment testing. For flight equipment and finite-lived intangibles used in our Dry Leasing segment, assets are tested on an individual basis for impairment. For assets classified as held for sale, an impairment is recognized when the fair value less the cost to sell the asset is less than its carrying amount. In developing estimates for flight equipment and cash flows, we use external appraisals and other industry data for the various equipment types, anticipated utilization of the assets, revenue generated, associated costs and length of service. Long-term Investments Long-term investments consist of debt securities, including accrued interest, for which management has the intent and ability to hold to maturity. These investments are classified as held-to-maturity and are reported at amortized cost. Interest on debt securities and accretion of discounts using the effective interest method are included in Interest income. Variable Interest Entities and Off-Balance Sheet Arrangements We hold a 50% interest in GATS GP (BVI) Ltd. (“GATS”), a joint venture with an unrelated third party. The purpose of the joint venture is to purchase rotable parts and provide repair services for those parts, primarily for our 747-8F aircraft. The joint venture is a . Our investment in GATS was $22.1 million as of December 31, 2017 and $22.2 million as of December 31, 2016 and our maximum exposure to losses from the entity is limited to our investment, which is composed primarily of rotable inventory parts. GATS does not have any third-party debt obligations. We had Accounts payable to GATS of $ million as of December 31, 2017 and $ million as of December 31, 2016. A portion of our operating aircraft are owned or effectively owned and leased through trusts established specifically to purchase, finance and lease aircraft to us. We have not consolidated any aircraft in the related trusts because we are not the primary beneficiary. Our maximum exposure under these operating leases is the remaining lease payments, which amounts are reflected in the future lease commitments more fully described in Note 10. Income Taxes Deferred income taxes are recognized for the tax consequences of reporting items in our income tax returns at different times than the items are reflected in our financial statements. These temporary differences result in deferred tax assets and liabilities that are calculated by applying enacted statutory tax rates applicable to future years to differences between the financial statement carrying amounts and the tax bases of existing assets and liabilities. If necessary, deferred income tax assets are reduced by a valuation allowance to an amount that is determined to be more likely than not recoverable. We must make significant estimates and assumptions about future taxable income and future tax consequences when determining the amount, if any, of the valuation allowance. We have recorded reserves for income taxes that may become payable in future years. Although management believes that its positions taken on income tax matters are reasonable, we have nevertheless established tax reserves in recognition that various taxing authorities may challenge certain of the positions taken by us, potentially resulting in additional liabilities for taxes. In accordance with recently issued SEC guidance to address the accounting for income tax reform, and based on our interpretation of the U.S. Tax Cuts and Jobs Act, we have recorded provisional income tax benefits in connection with the remeasurement of our U.S. net deferred tax liability. We have not recorded any provisional amount in connection with the one-time deemed repatriation tax on unremitted foreign earnings (see Note 11). The ultimate impact of the U.S. Tax Cuts and Jobs Act may differ from the provisional amounts reflected in our consolidated financial statements due to additional regulatory guidance that may be issued, changes in interpretations and assumptions, additional analysis, and actions we may take as a result. We expect to update these provisional amounts as the analysis is finalized within the one-year measurement period. Heavy Maintenance Except for engines used on our 747-8F aircraft, we account for heavy maintenance costs for airframes and engines used in our ACMI and Charter segments using the direct expense method. Under this method, heavy maintenance costs are charged to expense upon induction, based on our best estimate of the costs. We account for heavy maintenance costs for airframes and engines used in our Dry Leasing segment and engines used on our 747-8F aircraft using the deferral method. Under this method, we defer the expense recognition of scheduled heavy maintenance events, which are amortized over the estimated period until the next scheduled heavy maintenance event is required. Amortization of deferred maintenance expense is included in Depreciation and amortization. The following table provides a summary of Deferred maintenance included within Deferred costs and other assets as of December 31: 2017 2016 Beginning balance, net $ 19,100 $ - Deferred maintenance costs 50,675 19,644 Amortization of deferred maintenance (5,907 ) (544 ) Ending balance, net $ 63,868 $ 19,100 Prepaid Maintenance Deposits Certain of our aircraft financing agreements require security deposits to our finance providers to ensure that we perform major maintenance as required. These are substantially refundable to us and are, therefore, accounted for as deposits and included in Prepaid maintenance and in Deferred costs and other assets. Such amounts were $37.3 million as of December 31, 2017 and $53.4 million at December 31, 2016. Foreign Currency While most of our revenues are denominated in U.S. dollars, our results of operations may be exposed to the effect of fluctuations in the U.S. dollar value of foreign currency-denominated operating revenues and expenses. Our largest exposures come from the Brazilian real. We do not currently have a foreign currency hedging program related to our foreign currency-denominated transactions. Gains or losses resulting from foreign currency transactions are included within Non-operating Expenses (Income). Stock-Based Compensation We have various stock-based compensation plans for certain employees and outside directors, which are described more fully in Note 15. We recognize based on the fair value on grant date We estimate option and restricted stock unit forfeitures at the time of grant and periodically revise those estimates in subsequent periods if actual forfeitures differ from those estimates. As a result, we record stock-based compensation expense only for those awards that are expected to vest. Legal and Regulatory Matters We are party to legal and regulatory proceedings with respect to a variety of matters. We evaluate the likelihood of an unfavorable outcome of these proceedings each quarter. Our judgments are subjective and are based on the status of the legal or regulatory proceedings, the merits of our defenses and consultation with legal counsel. Due to the inherent uncertainties of the legal and regulatory proceedings in the multiple jurisdictions in which we operate, our judgments may be different from the actual outcomes. Supplemental Cash Flow Information Cash interest paid to lenders is calculated on the face amount of our various debt instruments based on the contractual interest rates in effect during each payment period. The following table summarizes interest and income taxes paid: 2017 2016 2015 Interest paid $ 73,872 $ 66,306 $ 75,135 Income taxes paid, net of refunds $ 563 $ 1,160 $ (228 ) The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total shown in the consolidated statements of cash flows: 2017 2016 Cash and cash equivalents $ 280,809 $ 123,890 Restricted cash 11,055 14,360 Total Cash, cash equivalents and restricted cash shown in consolidated statements of cash flows $ 291,864 $ 138,250 Recent Accounting Pronouncements In March 2016, the Financial Accounting Standards Board (“FASB”) amended its accounting guidance for share-based compensation. The amended guidance changes how companies account for certain aspects of share-based payment awards to employees, including the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. We adopted this amended guidance on January 1, 2017 on a prospective basis. As a result, we recognized $1.9 million of excess tax benefits during the year ended December 31, 2017 as a reduction of income tax expense in our consolidated statements of operations. Excess tax benefits were previously recognized within equity. Additionally, our consolidated statements of cash flows present such excess tax benefits, which were previously presented as a financing activity, as an operating activity. In February 2016, the FASB amended its accounting guidance for leases. The guidance requires a lessee to recognize assets and liabilities on the balance sheet arising from leases with terms greater than 12 months. While lessor accounting guidance is relatively unchanged, certain amendments were made to conform with changes made to lessee accounting and the amended revenue recognition guidance. The new guidance will continue to classify leases as either finance or operating, with classification affecting the presentation and pattern of expense and income recognition, in the statement of operations. It also requires additional quantitative and qualitative disclosures about leasing arrangements. The amended guidance is effective as of the beginning of 2019, with early adoption permitted. While we are still assessing the impact the amended guidance will have on our financial statements, we expect that recognizing the right-of-use asset and related lease liability will impact our balance sheet materially. We plan to adopt the new guidance on its required effective date of January 1, 2019 In May 2014, the FASB amended its accounting guidance for revenue recognition. Subsequently, the FASB has issued several clarifications and updates. The fundamental principles of the new guidance are that companies should recognize revenue in a manner that reflects the timing of the transfer of services to customers and consideration that a company expects to receive for the services provided. It also requires additional disclosures necessary for the financial statement users to understand the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. The two permitted transition methods under the guidance are the full retrospective approach, under which the guidance is applied to all periods presented, or the modified retrospective approach, under which the guidance is applied only to the most current period presented. We adopted this amended guidance on January 1, 2018 using the modified retrospective approach and we do not believe it will have a material effect on our financial statements. As a result of adoption, revenue recognized under previous guidance based on flight departure will be recognized over time as the services are performed. In addition, revenue under certain ACMI and CMI contracts, such as revenue related to contracted minimum block hour guarantees, will be recognized in later periods, and some revenue adjustments related to meeting or exceeding on-time performance targets will be recognized in earlier periods.

DHL Investment and Polar

DHL Investment and Polar	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
DHL Investment And Polar	3. DHL Investment and Polar DHL Network Operations (USA), Inc. (“DHL”), a subsidiary of Deutsche Post AG (“DP”), holds a 49% equity interest and a 25% voting interest in Polar. Polar is a . Under a 20-year blocked space agreement, which began in 2008 (the “BSA”), In accordance with the DHL Agreements, Polar flies for DHL’s transpacific express network and DHL provides financial support and assumes the risks and rewards of the operations of Polar The BSA established DHL’s capacity purchase commitments on Polar flights. DHL has the right to terminate the 20-year BSA at the twelfth and fifteenth anniversaries of commencement, which was October 27, 2008. Either party may terminate for cause (as defined) at any time. With respect to DHL, “cause” includes Polar’s inability to meet certain departure and arrival criteria for an extended period of time and upon certain change-of-control events, in which case DHL may be entitled to liquidated damages from Polar. Except for any liquidated damages that we could incur as described above, we do not have any continuing financial exposure to fund debt obligations or operating losses of Polar. Combined with Polar, we provide ACMI, CMI, Charter and Dry Leasing services to support DHL’s transpacific express, North American, intra-Asian, and global networks. In addition, we fly between the Asia Pacific region, the Middle East and Europe on behalf of DHL and other customers. Atlas also provides incremental charter capacity to Polar and DHL from time to time. The following table summarizes the aircraft types, services and number of aircraft provided to DHL as of December 31, 2017: Aircraft Service Total 747-8F ACMI 6 747-400F ACMI 8 777-200LRF CMI 5 767-300 CMI and Dry Leasing 4 767-200 CMI 9 737-400F CMI 5 757-200F Dry Leasing 1 Total 38 The following table summarizes our transactions with Polar: Revenue and Expenses: 2017 2016 2015 Revenue from Polar $ 420,564 $ 407,891 $ 399,113 Ground handling and airport fees to Polar 2,746 1,667 2,019 Accounts receivable/payable as of December 31: 2017 2016 Receivables from Polar $ 9,558 $ 8,161 Payables to Polar 2,751 2,019 Aggregate Carrying Value of Polar Investment as of December 31: 2017 2016 Aggregate Carrying Value of Polar Investment $ 4,870 $ 4,870

Southern Air Acquisition

Southern Air Acquisition	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Southern Air Acquisition	4. Southern Air Acquisition On April 7, 2016, we completed the acquisition of Southern Air and its subsidiaries, including Southern Air Inc. and Florida West International Airways, Inc. (“Florida West”). The acquisition of Southern Air provided us with immediate entry into 777 and 737 aircraft operating platforms, with the potential for developing additional business with existing and new customers. We believe this augments our ability to offer the broadest array of aircraft and services for domestic, regional and international operations. Southern Air currently flies five 777-200LRF and five 737-400F aircraft under CMI agreements for DHL. Total consideration for Southern Air was $105.8 million, net of cash acquired, and consisted of the following: Fair value of consideration Cash paid, net of $15,615 cash acquired $ 107,498 Working capital adjustment (2,106 ) Other adjustments 372 Total consideration $ 105,764 Tangible and identifiable intangible assets acquired and liabilities assumed were recorded at fair value as of the acquisition date. The following table summarizes the amounts recognized for fair values of the assets acquired and liabilities assumed: Estimated Fair Value Accounts receivable, net $ 22,912 Prepaid expenses and other current assets 2,434 Property and equipment 6,355 Intangible assets and goodwill 67,341 Deferred income taxes, net 36,452 Other assets 1,498 Total assets acquired $ 136,992 Accounts payable and accrued liabilities $ 31,228 Total liabilities assumed 31,228 Net assets acquired $ 105,764 The fair values and initial useful lives assigned to all intangible assets and goodwill are as follows: Estimated Useful Lives Estimated Fair Value Customer relationship 16 years $ 26,280 Trade name 1.5 years 700 Goodwill Indefinite 40,361 Total intangible assets and goodwill $ 67,341 Customer relationship represents the underlying relationship and agreements with DHL. The trade name relates to the Southern Air brand. Goodwill is primarily attributable to the expanded market opportunities expected from combining the service offerings of Southern Air with ours, as well as the employee work force acquired. Southern Air’s results of operations and goodwill are reflected in our ACMI segment. For 2016, our consolidated results include Southern Air’s operating revenue of $79.8 million. W e incurred Transaction-related expenses of $4.5 million in 2017, primarily related to professional fees and integration costs, and $17.7 million in 2016, primarily related to: certain compensation costs, including employee termination benefits; professional fees; and integration costs associated with the acquisition. The unaudited pro forma operating revenue for 2016 and 2015 was $1,866.7 million and $1,912.4 million, respectively. This pro forma information has been calculated as if the acquisition had taken place on January 1, 2015 and is not necessarily indicative of the net sales that actually would have been achieved. This information includes adjustments to conform with our accounting policies. The earnings of Southern Air were not material and, accordingly, pro forma and actual earnings information have not been presented. As part of integrating Southern Air, management decided and committed to pursue a plan to sell Florida West. As a result, the financial results for Florida West are presented as a discontinued operation and the assets and liabilities of Florida West were classified as held for sale, since the date of acquisition through December 31, 2016. The aggregate carrying value of Florida West’s assets held for sale was insignificant at December 31, 2016 and was included in Prepaid expenses and other current assets. In February 2017, management determined that a sale was no longer likely to occur and committed to a plan to wind down the Florida West operations. The wind-down of operations was completed in March 2017. A summary of the employee termination benefit liabilities, which are expected to be paid by the first quarter of 2018, is as follows: 2017 2016 Beginning balance $ 1,214 $ 3,797 Wind-down expenses 1,990 - Cash payments (3,133 ) (2,583 ) Ending balance $ 71 $ 1,214

Special Charge

Special Charge	12 Months Ended
	Dec. 31, 2017
Aircraft And Aircraft Engines Held For Sale [Abstract]
Special Charge	5. Special Charge During 2016 and 2015, we recognized $10.1 million of impairment losses for six CF6-80 engines classified as held for sale and $8.3 million for five CF6-80 engines classified as held for sale, respectively. Depreciation ceased on the engines. Nine engines were traded in during 2016 and one engine was traded in during 2017. The carrying value of the remaining CF6-80 engine held for sale at December 31, 2017 was $1.3 million, and of the two CF6-80 engines held for sale at December 31, 2016 was $2.8 million, which was included within Prepaid expenses and other current assets in the consolidated balance sheets. The remaining CF6-80 engine classified as held for sale is under contract to be traded in during the first quarter of 2018. During 2015, we recognized a charge of $7.7 million related to the early termination of high-cost operating leases for two CF6-80 engines.

Intangible Assets, Net and Good

Intangible Assets, Net and Goodwill	12 Months Ended
	Dec. 31, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Intangible Assets, Net and Goodwill	6. Intangible Assets, Net and Goodwill The following table presents our Intangible assets, net and goodwill as of December 31: 2017 2016 Goodwill $ 40,361 $ 40,361 Fair value adjustments on operating leases 45,531 45,531 Lease intangible 54,891 57,203 Customer relationship 26,280 26,280 Trade name 700 700 Less: accumulated amortization (61,278 ) (54,046 ) $ 106,485 $ 116,029 Goodwill is primarily attributable to the expanded market opportunities expected from combining the service offerings of Southern Air with ours, as well as the employee work force acquired. Fair value adjustments on operating leases represent the capitalized discount recorded in prior years to adjust the lease commitments for our 747-400 aircraft to fair market value and are Amortization expense related to intangible assets amounted to $9.5 million in 2017, $9.8 million in 2016 and $8.9 million in 2015. The estimated future amortization expense of intangible assets as of December 31, 2017 is as follows: 2018 $ 8,792 2019 8,094 2020 8,047 2021 8,547 2022 8,862 Thereafter 23,782 Total $ 66,124

Amazon

Amazon	12 Months Ended
	Dec. 31, 2017
Warrants And Rights Note Disclosure [Abstract]
Amazon	7. Amazon In May 2016, we entered into certain agreements with Amazon.com, Inc. and its subsidiary, Amazon Fulfillment Services, Inc., (collectively “Amazon”), which involve, among other things, CMI operation of 20 Boeing 767-300 freighter aircraft for Amazon by Atlas, as well as Dry Leasing by Titan. The Dry Leases have a term of ten years from the commencement of each agreement, while the CMI operations are for seven years from the commencement of each agreement (with an option for Amazon to extend the term to a total of ten years). Between August 2016 and December 2017, we have placed 12 freighter aircraft into service for Amazon and we expect to be operating all 20 before the end of 2018. In conjunction with these agreements, we granted Amazon a warrant providing the right to acquire up to 20% of our outstanding common shares, after giving effect to the issuance of shares pursuant to the warrants, at an exercise price of $37.50 per share. A portion of the warrant, representing the right to purchase 3.75 million shares, vested immediately upon issuance of the warrant. The remainder of the warrant, representing the right to purchase 3.75 million shares, would vest in increments of 375,000 as the lease and operation of each of the 11 th th The agreements also provide incentives for future growth of the relationship as Amazon may increase its business with us. In that regard, we granted Amazon a warrant to acquire up to an additional 10% of our outstanding common shares, after giving effect to the issuance of shares pursuant to the warrants, for an exercise price of $37.50 per share. This warrant to purchase 3.75 million shares would vest in conjunction with payments by Amazon for additional business with us. As of December 31, 2017, no portion of this warrant has vested. Upon vesting, the warrant would become exercisable in accordance with its terms through 2023. At a special meeting on September 20, 2016, the Company’s shareholders, by a vote of approximately 99.9% of the votes cast, approved the issuance of warrants to acquire up to 30% of our outstanding common shares. This approval constituted a change in control, as defined under certain of the Company’s benefit plans. As a result, we recognized $23.5 million in expense, including accelerated compensation expense for restricted and performance share and cash awards, during 2016. The share-based portion of the compensation expense was $13.3 million. At the time of vesting, the fair value of the vested portion of the warrant issued to Amazon is recorded as a warrant liability within Financial instruments and other liabilities (the “Amazon Warrant”). This initial fair value of the vested portion of the warrant is also recognized as a customer incentive asset within Deferred costs and other assets, net and is amortized as a reduction of revenue in proportion to the amount of revenue recognized over the terms of the Dry Leases and CMI agreements. The following table provides a summary of the customer incentive asset as of December 31: 2017 2016 Beginning balance $ 92,351 $ - Initial value for vested portion of warrant 19,448 92,888 Amortization of customer incentive asset (5,261 ) (537 ) Ending balance $ 106,538 $ 92,351 The Amazon Warrant liability is marked-to-market at the end of each reporting period with changes in fair value recorded in Unrealized loss (gain) on financial instruments. We utilize a Monte Carlo simulation approach to estimate the fair value of the Amazon Warrant which requires inputs such as our common stock price, the warrant strike price, estimated common stock price volatility and risk-free interest rate, among others. We recognized a net unrealized loss of $12.5 million and $2.9 million on the Amazon Warrant during 2017 and 2016, respectively. The fair value of the Amazon Warrant liability was $127.8 million as of December 31, 2017 and $95.8 million as of December 31, 2016.

Accrued Liabilities

Accrued Liabilities	12 Months Ended
	Dec. 31, 2017
Accrued Liabilities Current And Noncurrent [Abstract]
Accrued Liabilities	8. Accrued Liabilities Accrued liabilities consisted of the following as of December 31: 2017 2016 Maintenance $ 156,042 $ 54,495 Customer maintenance reserves 89,037 81,830 Salaries, wages and benefits 65,546 55,063 U.S. class action settlement 30,000 35,000 Aircraft fuel 22,196 16,149 Deferred revenue 20,986 10,298 Other 71,036 68,052 Accrued liabilities $ 454,843 $ 320,887

Debt

Debt	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Debt	9. Debt Our debt obligations, as of December 31: 2017 2016 Range of Maturity Dates Interest Rates (1) Balance Interest Rates (1) Balance Ex-Im Guaranteed Notes 2021 to 2025 1.89% $ 564,184 1.89% $ 645,537 Term loans and capital leases 2020 to 2032 4.16% 1,145,116 4.34% 1,053,273 Private Placement Facility 2025 to 2026 3.17% 144,539 - - Convertible Notes 2022 to 2024 2.04% 513,500 2.25% 224,500 EETC 2019 7.52% 11,480 7.52% 20,084 Total principal amount of debt and capital leases 2,378,819 1,943,394 Less: unamortized debt discount and issuance costs (151,820 ) (91,983 ) Total debt 2,226,999 1,851,411 Less current portion of debt and capital leases (218,013 ) (184,748 ) Long-term debt $ 2,008,986 $ 1,666,663 (1) Interest rates reflect weighted-average rates as of year-end. Many of our financing instruments have cross-default provisions and contain limitations on our ability to, among other things, consummate certain asset sales, merge or consolidate with any other person or sell, assign, transfer, lease, convey or otherwise dispose of all or substantially all of our assets. Description of our Debt Obligations Ex-Im Guaranteed Notes We have issued various notes guaranteed by the Export-Import Bank of the United States (“Ex-Im Bank”), each secured by a mortgage on a 747-8F or 777-200LRF aircraft (the “Ex-Im Guaranteed Notes”). In connection with the issuance of Ex-Im Guaranteed Notes, we paid usual and customary commitment and other fees associated with this type of financing. In addition, there are customary covenants, events of default and certain operating conditions that we must meet for the Ex-Im Guaranteed Notes. These notes accrue interest at a fixed rate with principal and interest payable quarterly. Term Loans and Capital Leases We have entered into various term loans to finance the purchase of aircraft, passenger-to-freighter conversion of aircraft, and for GEnx engine performance upgrade kits and overhauls. Each term loan requires payment of principal and interest quarterly in arrears. Funds available under each term loan are subject to usual and customary fees, and funds drawn typically bear interest at a fixed rate based on LIBOR, plus a margin. Each facility is guaranteed by us and subject to customary covenants and events of default. The following table summarizes the terms for each term loan entered into during 2017 (in millions): Issue Face Collateral Original Fixed Interest Date Value Type Term Rate First 2017 Term Loan April 2017 $ 20.1 767-300 91 months 3.02% Second 2017 Term Loan April 2017 21.3 767-300 91 months 3.16% Third 2017 Term Loan May 2017 21.5 767-300 91 months 3.16% Fourth 2017 Term Loan June 2017 21.3 767-300 91 months 3.09% Fifth 2017 Term Loan June 2017 21.7 767-300 91 months 3.11% Sixth 2017 Term Loan June 2017 21.7 767-300 91 months 3.11% Seventh 2017 Term Loan June 2017 18.7 None 58 months 2.17% Eighth 2017 Term Loan July 2017 12.5 767-300 60 months 3.62% Ninth 2017 Term Loan Nov 2017 26.9 None 60 months 2.38% Total $ 185.7 In March 2017, we amended and extended a lease for a 747-400 freighter aircraft to June 2032 at a lower monthly lease payment. As a result of the extension, we determined that the lease qualifies as a capital lease. The present value of the future minimum lease payments was $32.4 million. Private Placement Facility In September 2017, we entered into a debt facility for a total of $145.8 million through private placement to finance the purchase and passenger-to-freighter conversion of six 767-300 freighter aircraft dry leased to Amazon (the “Private Placement Facility”). The Private Placement Facility consists of six separate loans (the “Private Placement Loans”). Each Private Placement Loan is comprised of an equipment note and an equipment term loan, both secured by the cash flows from a 767-300 freighter aircraft dry lease and the underlying aircraft. The equipment notes require payment of principal and interest at a fixed interest rate. The equipment term loans accrue interest, at a fixed rate, which is added to the principal balance outstanding until each equipment note is paid in full. Subsequently, the equipment term loans require payment of principal and interest over the remaining term of the loans. The Private Placement Loans are cross-collateralized, but not cross-defaulted, with each other and, except for certain specified events, are not cross-defaulted with other debt facilities of the Company. In connection with entry into the Private Placement Facility, we have agreed to pay usual and customary commitment and other fees associated with this type of financing. The Private Placement Facility is guaranteed by us and subject to customary covenants and events of default. The following table summarizes the terms for each financing entered into during 2017 under the Private Placement Facility (in millions): Issue Face Collateral Original Fixed Interest Date Value Type Term Rate First 2017 Equipment Note Oct 2017 $ 21.2 Dry Lease and 767-300 87 months 2.93% First 2017 Equipment Term Loan Oct 2017 2.6 Dry Lease and 767-300 103 4.75% Second 2017 Equipment Note Oct 2017 21.4 Dry Lease and 767-300 88 months 2.93% Second 2017 Equipment Term Loan Oct 2017 3.2 Dry Lease and 767-300 107 months 4.75% Third 2017 Equipment Note Oct 2017 21.2 Dry Lease and 767-300 87 months 2.93% Third 2017 Equipment Term Loan Oct 2017 3.0 Dry Lease and 767-300 105 months 4.75% Fourth 2017 Equipment Note Dec 2017 21.2 Dry Lease and 767-300 88 months 2.93% Fourth 2017 Equipment Term Loan Dec 2017 2.9 Dry Lease and 767-300 104 4.87% Fifth 2017 Equipment Note Dec 2017 21.4 Dry Lease and 767-300 89 months 2.93% Fifth 2017 Equipment Term Loan Dec 2017 3.2 Dry Lease and 767-300 107 months 4.87% Sixth 2017 Equipment Note Dec 2017 21.4 Dry Lease and 767-300 88 months 2.93% Sixth 2017 Equipment Term Loan Dec 2017 3.1 Dry Lease and 767-300 106 months 4.94% Total $ 145.8 Convertible Notes In May 2017, we issued $289.0 million aggregate principal amount of convertible senior notes that mature on June 1, 2024 (the “2017 Convertible Notes”) in an underwritten public offering. In June 2015, we issued $224.5 million aggregate principal amount of convertible senior notes that mature on June 1, 2022 (the “2015 Convertible Notes”) in an underwritten public offering. The 2017 Convertible Notes and the 2015 Convertible Notes (collectively, the “Convertible Notes”), are senior unsecured obligations and accrue interest payable semiannually on June 1 and December 1 of each year. The Convertible Notes are due on their respective maturity dates, unless earlier converted or repurchased pursuant to their respective terms. The following table lists certain key terms for the Convertible Notes: 2017 Convertible Note 2015 Convertible Note Fixed interest rate 1.88 % 2.25 % Earliest conversion date September 1, 2023 September 1, 2021 Initial conversion price per share $ 61.08 $ 74.05 Conversion rate (shares for each $1,000 of principal) 16.3713 13.5036 We used the majority of the net proceeds from the 2017 Convertible Notes in May 2017 to repay $150.0 million then outstanding under our revolving credit facility and to fund the cost of the convertible note hedges described below. During 2015, we used the majority of the proceeds from the 2015 Convertible Notes to refinance higher-rate equipment notes funded by enhanced equipment trust certificates (“EETCs”) related to five 747-400 freighter aircraft owned by us in the aggregate amount of $187.8 million. The EETCs had an average cash coupon of 8.1%. In connection with the refinancing, we recognized a $66.7 million loss on early extinguishment of debt, of which $34.0 million was related to debt extinguishment costs paid to the EETC equipment note holders and $32.7 million was related to the write-off of the debt discount associated with the EETCs. The debt extinguishment costs paid are reflected as a financing activity in the consolidated statements of cash flows. As a result of this refinancing, we recognized a $13.4 million Gain on investments from the early redemption of certain investments related to EETCs in 2015 (see Note 12). The Convertible Notes will initially be convertible into shares of our common stock based on the respective conversion rates, which are equal to the respective initial conversion prices per share. The conversion rates will be subject to adjustment upon the occurrence of certain specified events but will not be adjusted for accrued and unpaid interest, except in certain limited circumstances. Upon the occurrence of a “make-whole fundamental change,” we will, in certain circumstances, increase the conversion rates by a number of additional shares of our common stock for the Convertible Notes converted in connection with such “make-whole fundamental change”. Additionally, if we undergo a “fundamental change,” holders will have the option to require us to repurchase all or a portion of their Convertible Notes for cash at a price equal to 100% of the principal amount of the Convertible Notes being repurchased plus any accrued and unpaid interest through, but excluding, the fundamental change repurchase date. In connection with the offerings of the Convertible Notes, we entered into convertible note hedge transactions whereby we have the option to purchase a certain number of shares of our common stock at a fixed price per share. In addition, we sold warrants to the option counterparties whereby the holders of the warrants have the option to purchase a certain number of shares of our common stock at a fixed price per share. The following table summarizes the convertible note hedges and related warrants: 2017 Convertible Note 2015 Convertible Note Convertible Note Hedges: Number of shares (1) 4,731,306 3,031,558 Initial price per share $ 61.08 $ 74.05 Cost of hedge $ 70,140 $ 52,903 Convertible Note Warrants: Number of shares (1) 4,731,306 3,031,558 Initial price per share $ 92.20 $ 95.01 Proceeds from sale of warrants $ 38,148 $ 36,290 (1) Taken together, the purchases of the convertible note hedges and the sales of the warrants are intended to offset any economic dilution from the conversion of each of the Convertible Notes when the stock price is below the exercise price of the respective warrants and to effectively increase the overall conversion prices from $61.08 to $92.20 per share for the 2017 Convertible Notes and from $74.05 to $95.01 per share On or after the earliest conversion date until the close of business on the second scheduled trading day immediately preceding the maturity date, a holder may convert all or a portion of its Convertible Notes. Upon conversion, each of the Convertible Notes will be settled, at our election, in cash, shares of our common stock, or a combination of cash and shares of our common stock. Our current intent and policy is to settle conversions with a combination of cash and shares of common stock with the principal amounts of the Convertible Notes paid in cash. Holders may only convert their Convertible Notes at their option at any time prior to the earliest conversion dates, under the following circumstances: • during any calendar quarter (and only during such calendar quarter) if, for each of at least 20 trading days (whether or not consecutive) during the 30 consecutive trading day period ending on, and including, the last trading day of the immediately preceding calendar quarter, the last reported sale price of our common stock for such trading day is equal to or greater than 130% of the conversion price on such trading day; • during the five consecutive business day period immediately following any five consecutive trading day period (the “measurement period”) in which, for each trading day of the measurement period, the trading price per $1,000 principal amount of the convertible notes for such trading day was less than 98% of the product of the last reported sale price of our common stock for such trading day and the conversion rate on such trading day; or • upon the occurrence of specified corporate events. We separately account for the liability and equity components of convertible notes. The carrying amount of the liability component is determined by measuring the fair value of a similar liability that does not have an associated conversion feature, assuming our nonconvertible unsecured debt borrowing rate. The carrying value of the equity component, the conversion option, which is recognized as additional paid-in-capital, net of tax, creates a debt discount on the convertible notes. The debt discount is determined by deducting the relative fair value of the liability component from the proceeds of the convertible notes and is amortized to interest expense using an effective interest rate of 6.14% and 6.44% over the term of the 2017 Convertible Notes and the 2015 Convertible Notes, respectively. The equity components will not be remeasured as long as they continue to meet the conditions for equity classification. The debt issuance costs related to the issuance of the Convertible Notes were allocated to the liability and equity components based on their relative values, as determined above. Total debt issuance costs for the 2017 Convertible Notes were $7.5 million, of which $5.7 million was allocated to the liability component and $1.8 million was allocated to the equity component. Total debt issuance costs for the 2015 Convertible Notes were $6.8 million, of which $5.2 million was allocated to the liability component and $1.6 million was allocated to the equity component. The debt issuance costs allocated to the liability components are amortized to interest expense using the effective interest method over the term of each of the Convertible Notes. The convertible notes consisted of the following as of December 31: 2017 2016 2017 Convertible Notes 2015 Convertible Notes 2015 Convertible Notes Remaining life in months 77 53 65 Liability component: Gross proceeds $ 289,000 $ 224,500 $ 224,500 Less: debt discount, net of amortization (65,187 ) (36,108 ) (42,956 ) Less: debt issuance cost, net of amortization (5,216 ) (3,445 ) (4,146 ) Net carrying amount $ 218,597 $ 184,947 $ 177,398 Equity component (1) $ 70,140 $ 52,903 $ 52,903 (1) Included in Additional paid-in capital on the consolidated balance sheets. The following table presents the amount of interest expense recognized related to the 2017 Convertible Notes and the 2015 Convertible Notes: For the Year Ended December 31, 2017 December 31, 2016 Contractual interest coupon $ 8,348 $ 5,051 Amortization of debt discount 11,801 6,421 Amortization of debt issuance costs 1,132 677 Total interest expense recognized $ 21,281 $ 12,149 EETC In 1999, we issued an EETC secured by a 747-400F aircraft in the amount of $109.9 million which matures in February 2019 with fixed interest rates on the underlying equipment notes ranging from 6.88% to 8.77% and an effective interest rate of 7.52%. Revolving Credit Facility In December 2016, we entered into a three-year $150.0 million secured revolving credit facility (the “Revolver”) for general corporate purposes, including financing the acquisition and conversion of 767 aircraft prior to obtaining permanent financing for the converted aircraft. The Revolver is secured by mortgages against nine 747-400 and five 767-300 aircraft, and related engines. Amounts outstanding under the Revolver are subject to borrowing base calculations, collateral coverage and fixed charge ratios. The Revolver accrues interest monthly at LIBOR plus a margin of 2.25% per annum on the amounts outstanding and 0.4% on the undrawn portion. In connection with entry into the Revolver, we paid usual and customary fees. There were no amounts outstanding at December 31, 2017 and 2016, and we had $139.3 million of unused availability under the Revolver as of December 31, 2017. Future Cash Payments for Debt and Capital Leases The following table summarizes the cash required to be paid by year and the carrying value 2018 $ 230,464 2019 230,537 2020 343,624 2021 238,223 2022 426,789 Thereafter 909,182 Total debt cash payments 2,378,819 Less: unamortized debt discount and issuance costs (151,820 ) Debt $ 2,226,999

Commitments

Commitments	12 Months Ended
	Dec. 31, 2017
Commitments And Contingencies Disclosure [Abstract]
Commitments	10. Commitments Leveraged Lease Structure In three separate transactions in 1998, 1999 and 2000, we issued EETCs to finance the acquisition of five 747-400F aircraft as leveraged leases. In a leveraged lease, the owner trustee is the owner of record for the aircraft. Wells Fargo Bank Northwest, National Association (“Wells Fargo”) serves as the owner trustee with respect to the leveraged leases in each of our EETC transactions. As the owner trustee of the aircraft, Wells Fargo serves as the lessor of the aircraft under the EETC lease between us and the owner trustee. Wells Fargo also serves as trustee for the beneficial owner of the aircraft, the owner participant. The original owner participant for each aircraft invested (on an equity basis) approximately 20% of the original cost of the aircraft. The remaining approximately 80% of the aircraft cost was financed with debt issued by the owner trustee on a nonrecourse basis in the form of equipment notes. The equipment notes were generally issued in three series, for each aircraft, designated as Series A, B and C equipment notes. The loans evidenced by the equipment notes were funded by the public offering of EETCs. Like the equipment notes, the EETCs were issued in three series, with each EETC transaction designated as Series A, B and C EETCs. Each series of EETCs was issued by the trustee for separate Atlas pass-through trusts with the same designation as the series of EETCs issued (“PTCs”). Each of these pass-through trustees is also the holder and beneficial owner of the equipment notes bearing the same series designation. These leasing entities meet the criteria for variable interest entities. We have not consolidated any of the aircraft-leasing trusts because we are not the primary beneficiary. We account for these leases as operating leases Operating Leases The following table summarizes rental expenses in: 2017 2016 2015 Aircraft and engines $ 142,945 $ 146,110 $ 145,031 Purchased capacity, office, vehicles and other $ 46,817 $ 23,727 $ 44,228 As of December 31, 2017, 15 of our 73 The following table summarizes our minimum annual rental commitments as of the periods indicated under non-cancelable aircraft, engine, real estate and other operating leases with initial or remaining terms of more than one year, reflecting the terms that were in effect as of December 31, 2017: Aircraft and Engine Other Operating Operating Leases Leases Total 2018 $ 138,223 $ 7,003 $ 145,226 2019 154,461 6,466 160,927 2020 149,214 5,908 155,122 2021 157,985 4,680 162,665 2022 111,064 1,843 112,907 Thereafter 109,993 27 110,020 Total minimum rental payments $ 820,940 $ 25,927 $ 846,867 In addition to the aircraft we Dry Lease to customers, Polar subleases aircraft from us that are leased from a third party and are included in the table above under aircraft operating leases. The following table summarizes the contractual amount of minimum income under Dry Leases and the non-cancelable aircraft subleases, reflecting the terms that were in effect as of December 31, 2017: Dry Lease Sublease Income Income Total 2018 $ 139,663 $ 52,800 $ 192,463 2019 127,597 - 127,597 2020 117,222 - 117,222 2021 98,668 - 98,668 2022 95,424 - 95,424 Thereafter 219,033 - 219,033 Total minimum lease receipts $ 797,607 $ 52,800 $ 850,407 Guarantees and Indemnifications In the ordinary course of business, we enter into numerous leasing and financing arrangements for real estate, equipment, aircraft and engines that have various guarantees included in the contracts. These guarantees are primarily in the form of indemnities. In both leasing and financing transactions, we typically indemnify the lessors and any financing parties against tort liabilities that arise out of the use, occupancy, manufacture, design, operation or maintenance of the leased premises or financed aircraft, regardless of whether these liabilities relate to the negligence of the indemnified parties. Currently, we believe that any future payments required under many of these guarantees or indemnities would be immaterial, as most tort liabilities and related indemnities are covered by insurance (subject to deductibles). However, payments under certain tax indemnities related to certain of our financing arrangements, if applicable, could be material, and would not be covered by insurance, although we believe that these payments are not probable. Certain leased premises, such as maintenance and storage facilities, typically include indemnities of such parties for any environmental liability that may arise out of or relate to the use of the leased premises. We also provide standard indemnification agreements to officers and directors in the ordinary course of business. Financings and Guarantees Our financing arrangements typically contain a withholding tax provision that requires us to pay additional amounts to the applicable lender or other financing party, if withholding taxes are imposed on such lender or other financing party as a result of a change in the applicable tax law. These increased costs and withholding tax provisions continue for the entire term of the applicable transaction and there is no limitation on the maximum additional amount we could be required to pay under such provisions. Any failure to pay amounts due under such provisions generally would trigger an event of default and, in a secured financing transaction, would entitle the lender to foreclose upon the collateral to realize the amount due.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	11. Income Taxes The United States enacted the U.S. Tax Cuts and Jobs Act on December 22, 2017. The U.S. Tax Cuts and Jobs Act reduces the U.S. federal corporate income tax rate from 35.0% to 21.0% beginning in 2018, requires companies to pay a one-time deemed repatriation tax on unremitted foreign earnings, repeals the corporate alternative minimum tax, provides full expensing of new and used assets, creates new sources of taxable income and deductions related to foreign operations, repeals or modifies certain deductions and credits, and modifies the use of federal net operating loss carryforwards (“NOLs”). On December 22, 2017, the SEC issued guidance which allows us to record provisional amounts during a measurement period not to extend beyond one year following enactment. As a result of that guidance, and based on our interpretation of the U.S. Tax Cuts and Jobs Act, we have recorded provisional income tax benefits of $130.0 million in connection with the remeasurement of our U.S. net deferred tax liability. We have not recorded any provisional amount in connection with the one-time deemed repatriation tax on unremitted foreign earnings. The ultimate impact of the U.S. Tax Cuts and Jobs Act may differ from the amounts reflected in these financial statements due to additional regulatory guidance that may be issued, changes in interpretations and assumptions, additional analysis, and actions the Company may take as a result. The Company expects to update these provisional amounts as the analysis is finalized within the one-year measurement period. A reconciliation of the provision (benefit) for income taxes applying the statutory federal income tax rate of 35.0% for each of the years ended December 31, is as follows: 2017 2016 2015 Current: Federal $ (133 ) $ (376 ) $ 52 State and local (99 ) (298 ) 48 Foreign 596 84 1,292 Total current expense 364 (590 ) 1,392 Deferred: Federal (87,185 ) 46,391 (24,425 ) State and local 1,868 (1,436 ) (3,531 ) Foreign 3,987 2,426 2,058 Total deferred expense (benefit) (81,330 ) 47,381 (25,898 ) Total income tax expense (benefit) $ (80,966 ) $ 46,791 $ (24,506 ) The domestic and foreign earnings before income taxes are as follows: 2017 2016 2015 Domestic $ 104,321 $ 61,006 $ (57,825 ) Foreign 39,051 28,410 40,605 Income (loss) before income taxes $ 143,372 $ 89,416 $ (17,220 ) A reconciliation of differences between the U.S. federal statutory income tax rate and the effective income tax rates is presented as a percent of expense (benefit) as follows: 2017 2016 2015 U.S. federal statutory income tax rate 35.0 % 35.0 % (35.0 %) State and local taxes based on income, net of federal benefit 0.3 % 1.10 % (2.0 %) Change in deferred foreign and state tax rates 0.6 % (2.2 %) (12.0 %) Nondeductible customer incentive related to Amazon 5.0 % 10.9 % 0.0 % Nondeductible compensation expenses related to Amazon — 13.0 % 0.0 % Other nondeductible expenses 1.4 % 4.3 % 10.2 % Extraterritorial income tax benefit — — (23.3 %) Tax incentives and additional deductions (0.6 %) (0.9 %) (4.9 %) Favorable resolution of income tax issues — — (13.8 %) Tax effect of foreign operations (7.7 %) (9.4 %) (66.4 %) Impact of U.S. Tax Cuts and Jobs Act (90.7 %) — — Other 0.2 % 0.5 % 4.9 % Effective income tax rate (56.5 %) 52.3 % (142.3 %) The effective income tax rate for the year ended December 31, 2017 differed from the U.S. statutory rate primarily due to the revaluation of our U.S. net deferred tax liability as a result of the U.S. Tax Cuts and Jobs Act, and to a lesser extent, nondeductible changes in the value of the Amazon Warrant liability (see Note 7). In 2016, we recorded a nondeductible customer incentive and nondeductible compensation expenses resulting from a change in control, as defined under certain of the Company’s benefit plans, both related to the Amazon transaction (see Note 7). We also generated non-recurring tax benefits from extraterritorial income (“ETI”) in 2015, which reduced our income tax rate in proportion to our income or loss in that year. Prior to the U.S. Tax Cuts and Jobs Act, we indefinitely reinvested outside of the U.S. the net earnings of our foreign Dry Leasing subsidiaries. Historically, we have not provided for U.S. taxes on the unremitted earnings of foreign subsidiaries that have not been previously taxed because we intended to invest such unremitted earnings indefinitely outside of the U.S. As a result of the U.S. Tax Cuts and Jobs Act, we are assessing our intent to invest such unremitted earnings outside the U.S. It is impracticable to provide for U.S. taxes on these unremitted earnings under the U.S. Tax Cuts and Jobs Act without regulatory guidance and additional analysis. We may repatriate the earnings of our foreign subsidiaries to the extent the associated taxes are insignificant. Deferred tax assets and liabilities represent the expected future tax consequences of temporary differences between the carrying amounts and the tax bases of assets and liabilities. The net noncurrent deferred tax asset (liability) was comprised of the following as of December 31: Assets (Liabilities) 2017 2016 Deferred tax assets: Net operating loss carryforwards and credits $ 345,245 $ 454,749 Accrued compensation 11,514 17,036 Accrued legal settlements 6,596 25,442 Aircraft leases 17,323 16,109 Goodwill and other intangibles 7,267 15,798 Interest rate derivatives 1,532 3,124 Long-term debt 1,923 3,409 Obsolescence reserve 5,734 7,804 Stock-based compensation 3,296 6,731 Other 977 685 Total deferred tax assets 401,407 550,887 Valuation allowance (30,869 ) (49,396 ) Net deferred tax assets $ 370,538 $ 501,491 Deferred tax liabilities: Fixed assets $ (562,210 ) $ (778,905 ) Accrued expenses - (10 ) Acquisition of EETC debt (1,247 ) (4,079 ) Incentive related to Amazon (6,709 ) (6,829 ) Deferred maintenance (14,151 ) (8,614 ) Total deferred tax liabilities $ (584,317 ) $ (798,437 ) Deferred taxes included within following balance sheet line items: Deferred taxes $ (214,694 ) $ (298,165 ) Deferred costs and other assets 915 1,219 Net deferred tax assets (liabilities) $ (213,779 ) $ (296,946 ) As of December 31, 2017 and 2016, we had U.S. NOLs, net of unrecognized tax benefits and valuation allowances, of approximately $1.2 billion and $1.0 billion, respectively, which will expire through 2037, if not utilized. The increase in NOLs during 2017 resulted primarily from accelerated tax depreciation. We had alternative minimum tax credits of $4.5 million and $4.7 million as of December 31, 2017 and 2016, respectively, with no expiration date. Pursuant to the U.S. Tax Cuts and Jobs Act, these credits are refundable on our income tax returns from 2018 through 2021. Additionally, we had foreign NOLs for Hong Kong and Singapore of approximately $465.3 million and $463.5 million as of December 31, 2017 and 2016, respectively, with no expiration date. We participate in an aircraft leasing incentive program in Singapore which entitles us to a reduced tax rate of 10.0% on our Singapore Dry Leasing income. Our participation is set to expire on July 31, 2018 at which time we expect it to be renewed at a further reduced rate of 8.0%. Should the program not be renewed, the tax rate would revert to 17.0%. Either result will have a material impact on our 2018 results. Section 382 of the Internal Revenue Code (the “Code”) imposes an annual limitation on the amount of a corporation’s U.S. federal taxable income that can be offset by NOLs if it experiences an “ownership change”, as defined. We experienced ownership changes, as defined, in 2004 and 2009. In addition, the acquisition of Southern Air in 2016 (see Note 4) constituted an ownership change for that entity. Accordingly, the use of NOLs generated prior to these ownership changes is subject to an annual limitation. If certain changes in our ownership occur prospectively, there could be an additional annual limitation on the amount of utilizable NOLs. On each reporting date, management assesses whether we are more likely than not to realize some or all of our deferred tax assets. After our assessment, we maintained a valuation allowance of $30.9 million and $49.4 million against our deferred tax assets as of December 31, 2017 and 2016, respectively. The valuation allowance decreased by $18.5 million during the year ended December 31, 2017 primarily due to the change in the federal income tax rate under the U.S. Tax Cuts and Jobs Act and by $1.3 million during the year ended December 31, 2016. The valuation allowance is attributable to a limitation on NOL utilization resulting from the ownership change under Section 382. Due to this limitation, we expect a portion of our NOLs generated in 2004 and prior years to eventually expire unused. A reconciliation of the beginning and ending unrecognized income tax benefits is as follows: 2017 2016 2015 Beginning balance $ 113,892 $ 112,555 $ 109,993 Additions for tax positions related to the current year 1,366 1,587 551 Additions for tax positions related to prior years 40 - 5,503 Reductions for tax positions related to prior years (43,581 ) (250 ) (3,492 ) Ending balance $ 71,717 $ 113,892 $ 112,555 The decrease in unrecognized income tax benefits during 2017 for tax positions related to prior years is due to the change in the federal income tax rate under the U.S. Tax Cuts and Jobs Act. If recognized, all of the unrecognized income tax benefits would favorably impact the effective income tax rate. We will maintain a liability for unrecognized income tax benefits until these uncertain positions are resolved or until the expiration of the applicable statute of limitations, if earlier. Our policy is to record tax-related interest expense and penalties, if applicable, as a component of income tax expense. We recorded no interest benefit in 2017 or 2016. The cumulative liability for tax-related interest was $0.1 million as of December 31, 2017 and $0.1 million as of December 31, 2016 For U.S. federal income tax purposes, the 2012 through 2017 income tax years remain subject to examination. The Company is currently undergoing a federal income tax examination for the tax year ending 2015 as well as income tax examinations in Illinois and New Jersey. The Company files income tax returns in multiple foreign jurisdictions, primarily in Singapore and Hong Kong. The 2012 through 2017 Singapore income tax years and 2010 through 2017 Hong Kong income tax years are subject to examination. The Company is currently undergoing income tax examinations in Hong Kong for the periods 2010 through 2016.

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Financial Instruments	12. Financial Instruments Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). Inputs used to measure fair value are classified in the following hierarchy: Level 1 Unadjusted quoted prices in active markets for identical assets or liabilities; Level 2 Other inputs that are observable directly or indirectly, such as quoted prices in active markets for similar assets or liabilities, or inactive quoted prices for identical assets or liabilities in inactive markets; Level 3 Unobservable inputs reflecting assumptions about the inputs used in pricing the asset or liability. We endeavor to utilize the best available information to measure fair value. The carrying value of Cash and cash equivalents, Short-term investments and Restricted cash is based on cost, which approximates fair value. Long-term investments consist of debt securities, maturing within five years, for which we have both the ability and the intent to hold until maturity. These investments are classified as held-to-maturity and reported at amortized cost. The fair value of our Long-term investments is based on a discounted cash flow analysis using the contractual cash flows of the investments and a discount rate derived from unadjusted quoted interest rates for debt securities of comparable risk. Such debt securities represent investments in PTCs related to EETCs issued by Atlas in 1998, 1999 and 2000. Interest on debt securities and accretion of discounts using the effective interest method are included in Interest income. Term loans and notes consist of term loans, Ex-Im Guaranteed Notes, the Private Placement Facility, the Revolver and EETCs. The fair values of these debt instruments are based on a discounted cash flow analysis using current borrowing rates for instruments with similar terms. The fair value of our convertible notes is based on unadjusted quoted market prices for these securities. The fair value of the Amazon Warrant is based on a Monte Carlo simulation which requires inputs such as our common stock price, the warrant strike price, estimated common stock price volatility, and risk-free interest rate, among others. The following table summarizes the carrying value, estimated fair value and classification of our financial instruments as of: December 31, 2017 Carrying Value Fair Value Level 1 Level 2 Level 3 Assets Cash and cash equivalents $ 280,809 $ 280,809 $ 280,809 $ - $ - Short-term investments 13,604 13,604 - - 13,604 Restricted cash 11,055 11,055 11,055 - - Long-term investments and accrued interest 15,371 18,074 - - 18,074 $ 320,839 $ 323,542 $ 291,864 $ - $ 31,678 Liabilities Term loans and notes $ 1,791,918 $ 1,844,445 $ - $ - $ 1,844,445 Convertible notes (1) 403,544 602,846 602,846 - - Amazon Warrant 127,755 127,755 - 127,755 - $ 2,323,217 $ 2,575,046 $ 602,846 $ 127,755 $ 1,844,445 December 31, 2016 Carrying Value Fair Value Level 1 Level 2 Level 3 Assets Cash and cash equivalents $ 123,890 $ 123,890 $ 123,890 $ - $ - Short-term investments 4,313 4,313 - - 4,313 Restricted cash 14,360 14,360 14,360 - - Long-term investments and accrued interest 27,951 33,161 - - 33,161 $ 170,514 $ 175,724 $ 138,250 $ - $ 37,474 Liabilities Term loans and notes $ 1,674,013 $ 1,739,744 $ - $ - $ 1,739,744 Convertible notes (1) 177,398 228,429 228,429 - - Amazon Warrant 95,775 95,775 - 95,775 - $ 1,947,186 $ 2,063,948 $ 228,429 $ 95,775 $ 1,739,744 (1) Carrying value is net of debt discounts and debt issuance costs. Hedge transactions associated with the Convertible Notes are reflected in additional paid-in-capital (see Note 9). Gross unrealized gains on our long-term investments and accrued interest were $2.7 million at December 31, 2017 and $5.2 million at December 31, 2016 . Our Long-term investments include investments in PTCs related to EETCs. During 2015, we repaid EETCs related to five 747-400 freighter aircraft owned by us using proceeds from the Convertible Notes (see Note 9). Following the refinancing, we recognized a $13.4 million Gain on investments resulting from the early redemption of certain PTCs, of which $5.7 million was related to the receipt of debt redemption premiums and $7.7 million was related to the recognition of deferred income on the PTCs purchased at a discount that have been repaid. The early redemption of PTCs does not impact our ability or intent to hold the remainder of our PTC investments to maturity.

Segment Reporting

Segment Reporting	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Segment Reporting	13. Segment Reporting Our business is organized into three operating segments based on our service offerings: ACMI, Charter and Dry Leasing. All segments are directly or indirectly engaged in the business of air transportation services but have different commercial and economic characteristics. Each operating segment is separately reviewed by our chief operating decision maker to assess operating results and make resource allocation decisions. We do not aggregate our operating segments and, therefore, our operating segments are our reportable segments. We use an economic performance metric (“Direct Contribution”) that shows the profitability of each segment after allocation of direct operating and ownership costs. Direct Contribution represents Income (loss) from continuing operations before income taxes excluding the following: Special charges, Transaction-related expenses, nonrecurring items, Losses (gains) on the disposal of aircraft, Losses on early extinguishment of debt, Unrealized losses (gains) on financial instruments, Gains on investments and Unallocated income and expenses, net. Direct operating and ownership costs include crew costs, maintenance, fuel, ground operations, sales costs, aircraft rent, interest expense on the portion of debt used for financing aircraft, interest income on debt securities and aircraft depreciation. Unallocated income and expenses, net include corporate overhead, nonaircraft depreciation, noncash expenses and income, interest expense on the portion of debt used for general corporate purposes, interest income on nondebt securities, capitalized interest, foreign exchange gains and losses, other revenue and other non-operating costs. Management allocates the costs attributable to aircraft operation and ownership among the various segments based on the aircraft type and activity levels in each segment. Depreciation and amortization expense, aircraft rent, maintenance expense, and other aircraft-related expenses are allocated to segments based upon aircraft utilization because certain individual aircraft are utilized across segments interchangeably. Other allocation methods are standard activity-based methods that are commonly used in the industry. The ACMI segment provides aircraft, crew, maintenance and insurance services to customers. Also included in the ACMI segment is CMI, whereby we provide crew, maintenance and insurance services but not the aircraft. Under ACMI and CMI contracts, customers generally guarantee a monthly level of operation at a predetermined rate for a defined period of time. The customer bears the commercial revenue risk and the obligation for other direct operating costs, including fuel. The Charter segment provides full-planeload air cargo and passenger aircraft charters to customers, including the U.S. Military Air Mobility Command (the “AMC”), brokers, freight forwarders, direct shippers, airlines, sports teams and fans, and private charter customers. Charter customers generally pay a fixed charter fee and we bear the direct operating costs. The Dry Leasing segment provides for the leasing of aircraft and engines to customers. Other represents revenue for services that are not allocated to any segment, including administrative and management support services and flight simulator training. The following table sets forth Operating Revenue and Direct Contribution for our reportable segments reconciled to Operating Income and Income (loss) from continuing operations before income taxes: For the Years Ended December 31, 2017 2016 2015 Operating Revenue: ACMI $ 988,741 $ 834,997 $ 791,442 Charter 1,034,562 881,991 908,753 Dry Leasing 119,820 105,795 107,218 Customer incentive asset amortization (5,261 ) (537 ) - Other 18,598 17,381 15,246 Total Operating Revenue $ 2,156,460 $ 1,839,627 $ 1,822,659 Direct Contribution: ACMI $ 231,271 $ 200,563 $ 185,615 Charter 151,388 133,727 124,808 Dry Leasing 39,939 33,114 42,023 Total Direct Contribution for Reportable Segments 422,598 367,404 352,446 Unallocated income and expenses, net (261,942 ) (242,768 ) (294,451 ) Loss on early extinguishment of debt (167 ) (132 ) (69,728 ) Unrealized loss on financial instruments (12,533 ) (2,888 ) - Gain on investments - - 13,439 Special charge (106 ) (10,140 ) (17,388 ) Transaction-related expenses (4,509 ) (22,071 ) - Gain (loss) on disposal of aircraft 31 11 (1,538 ) Income (loss) from continuing operations before income taxes 143,372 89,416 (17,220 ) Add back (subtract): Interest income (6,009 ) (5,532 ) (12,554 ) Interest expense 99,687 84,650 96,756 Capitalized interest (7,389 ) (3,313 ) (1,027 ) Loss on early extinguishment of debt 167 132 69,728 Unrealized loss on financial instruments 12,533 2,888 - Gain on investments - - (13,439 ) Other (income) expense (387 ) 70 1,261 Operating Income $ 241,974 $ 168,311 $ 123,505 Given the nature of our business and international flying, geographic information for revenue, long-lived assets and total assets is not presented because it is impracticable to do so. We are exposed to a concentration of revenue from the AMC, Polar and DHL (see Note 3 for further discussion regarding Polar). No other customer accounted for more than 10.0% of our Total Operating Revenue. Revenue from the AMC was $496.3 million for 2017, $436.1 million for 2016 and $418.3 million 2015. Revenue from DHL was $262.6 million for 2017, $195.1 million for 2016 and $113.0 million for 2015. We have not experienced any credit issues with either of these customers. 2017 2016 2015 Depreciation and amortization expense: ACMI $ 71,097 $ 61,630 $ 62,253 Charter 36,539 37,239 27,294 Dry Leasing 47,426 40,164 31,326 Unallocated 11,651 9,843 7,867 Total Depreciation and Amortization $ 166,713 $ 148,876 $ 128,740

Labor and Legal Proceedings

Labor and Legal Proceedings	12 Months Ended
	Dec. 31, 2017
Labor And Legal Proceedings [Abstract]
Labor and Legal Proceedings	14. Labor and Legal Proceedings Labor Pilots of Atlas and Southern Air, and flight dispatchers of Atlas and Polar, are represented by the International Brotherhood of Teamsters (the “IBT”). We have a five-year collective bargaining agreement (“CBA”) with our Atlas pilots, which became amendable in September 2016, and a four-year CBA with the Southern Air pilots, which became amendable in November 2016. We also have a five-year CBA with our Atlas and Polar dispatchers, which was extended in April 2017 for an additional four years, making the CBA amendable in November 2021. After we completed the acquisition of Southern Air in April 2016, we informed the IBT of our intention to pursue (and we have been pursuing) a complete operational merger of Atlas and Southern Air. Pursuant to the merger provisions in both the Atlas and Southern Air CBAs, joint negotiations for a single CBA for Atlas and Southern Air should commence promptly. Further to this process, once a seniority list is presented to us by the unions, it triggers an agreed-upon time frame to negotiate a new joint CBA with any unresolved issues submitted to binding arbitration. After the merger process began, the IBT filed an application for mediation with the National Mediation Board (“NMB”) on behalf of the Atlas pilots, and subsequently the IBT filed a similar application on behalf of Southern Air pilots. We have opposed both mediation applications as they are not in accordance with the merger provisions in the parties’ existing CBAs. The Atlas and Southern Air CBAs have a defined and streamlined process for negotiating a joint CBA when a merger occurs, as in the case with the Atlas and Southern Air merger. The NMB conducted a pre-mediation investigation on the IBT’s Atlas application in June 2016, which is currently pending (along with the IBT’s Southern Air application). Due to a lack of meaningful progress in such merger discussions, in February 2017, we filed a lawsuit against the IBT to compel arbitration on the issue of whether the merger provisions in Atlas and Southern Air's CBAs apply to the bargaining process. While this lawsuit is pending in the Southern District Court of New York, the Company and the IBT have reached an interim agreement on a process to proceed with negotiations for a new joint CBA. These negotiations commenced on July 6, 2017 and the parties have continued to meet regularly since then and bargain for a new joint CBA. In September 2017, the Company requested the U.S. District Court for the District of Columbia (the “Court”) to issue a preliminary injunction to require the IBT to meet its obligations under the Railway Labor Act of 1926 (the “Railway Labor Act”) and stop the intentional and illegal work slowdowns and service interruptions. In its filing, the Company states that the IBT is engaging in unlawful, concerted work slowdowns to gain leverage in pilot contract negotiations with the Company. The Company sought to have the Court compel the IBT to stop the illegal work actions and return to normal operations. The hearing was completed in early November 2017. In late November 2017, the Court granted the Company’s request to issue a preliminary injunction to require the IBT to meet its obligations under the Railway Labor Act and stop “authorizing, encouraging, permitting, calling, engaging in, or continuing” any illegal pilot slowdown activities, which were intended to gain leverage in pilot contract negotiations with the Company. In addition, the Court ordered the IBT to take affirmative action to prevent and to refrain from continuing any form of interference with the Company’s operations or any other concerted refusal to perform normal pilot operations consistent with its status quo obligations under the Railway Labor Act. We are subject to risks of work interruption or stoppage as permitted by the Railway Labor Act and may incur additional administrative expenses associated with union representation of our employees. Matters Related to Alleged Pricing Practices The Company and Polar Air Cargo, LLC (“Old Polar”), a consolidated subsidiary, were named defendants, along with a number of other cargo carriers, in several class actions in the U.S. arising from allegations about the pricing practices of Old Polar and a number of air cargo carriers. These actions were all centralized in the U.S. District Court for the Eastern District of New York. Polar was later joined as an additional defendant. The consolidated complaint alleged, among other things, that the defendants, including the Company and Old Polar, manipulated the market price for air cargo services sold domestically and abroad through the use of surcharges, in violation of U.S., state, and European Union antitrust laws. The suit sought treble damages and attorneys’ fees. On January 7, 2016, the Company, Old Polar, and Polar entered into a settlement agreement to settle all claims by participating class members against the Company, Old Polar and Polar. The Company, Polar, and Old Polar deny any wrongdoing, and there is no admission of any wrongdoing in the settlement agreement. Pursuant to the settlement agreement, which was approved by the U.S. District Court for the Eastern District of New York, the Company, Old Polar and Polar have made installment payments over three years to settle the plaintiffs’ claims, with the last payment of $30.0 million in January 2018. In the United Kingdom, several groups of named claimants have brought suit against British Airways in connection with the same alleged pricing practices at issue in the proceedings described above and are seeking damages allegedly arising from that conduct. British Airways has filed claims in the lawsuit against Old Polar and a number of air cargo carriers for contribution should British Airways be found liable to claimants. Old Polar’s formal statement of defense was filed on March 2, 2015. On October 14, 2015, the U.K. Court of Appeal released decisions favorable to the defendant and contributory defendants on two matters under appeal. Permission was sought to appeal the U.K. Court of Appeal's decisions to the U.K. Supreme Court and was denied. In December 2015, certain claimants settled with British Airways removing a significant portion of the claim against British Airways and therefore reducing the potential contribution required by the other airlines, including Old Polar. On December 16, 2015, the European General Court released decisions annulling decisions that the European Commission made against the majority of the air cargo carriers. The European Commission did not appeal the General Court decision but has, in early 2017, reissued a revised decision to which Old Polar is, again, not an addressee. On April 13, 2017, Old Polar and claimants represented by Hausfeld & Co. LLP (the “Hausfeld Claimants”) entered into a bilateral settlement agreement in relation to the English proceedings (the “Settlement Agreement”). The Settlement Agreement contains a mechanism by which the Hausfeld Claimants will release Old Polar and remove from the English proceedings all claims for damages alleged by the Hausfeld Claimants to be attributable to air cargo purchases from Old Polar (and each of Old Polar’s parents, subsidiaries, affiliates, predecessors, successors, agents and assignees). The amount of the settlement, which is tax deductible and was previously accrued for, was paid during the second quarter of 2017 and did not have a material adverse effect on the Company’s financial condition, results of operations or cash flows. Old Polar remains a contributory defendant in the proceedings and, as such, may be subject to certain continuing evidentiary obligations. In the Netherlands, Stichting Cartel Compensation, successor in interest to claims of various shippers, has filed suit in the district court in Amsterdam against British Airways, KLM, Martinair, Air France, Lufthansa and Singapore Airlines seeking recovery for damages purportedly arising from the same pricing practices at issue in the proceedings described above. In response, British Airways, KLM, Martinair, Air France and Lufthansa filed third-party indemnification lawsuits against Old Polar and Polar seeking indemnification in the event the defendants are found to be liable in the main proceedings. The Netherlands proceedings are ongoing and, like the U.K. proceedings, are likely to be affected by the European Commission’s revised decision. We are unable to reasonably predict the outcome of the litigation. If the Company, Old Polar or Polar were to incur an unfavorable outcome in connection with this proceeding, such outcome may have a material adverse effect on our business, financial condition, results of operations or cash flows. We are unable to reasonably estimate a range of possible loss for this matter at this time. Brazilian Customs Claim Old Polar was cited for two alleged customs violations in Sao Paulo, Brazil, relating to shipments of goods dating back to 1999 and 2000. Each claim asserts that goods listed on the flight manifest of two separate Old Polar scheduled service flights were not on board the aircraft upon arrival and therefore were improperly brought into Brazil. The two claims, which also seek unpaid customs duties, taxes and penalties from the date of the alleged infraction, are approximately $9.2 million in aggregate based on December 31, 2017 exchange rates. In both cases, we believe that the amounts claimed are substantially overstated due to a calculation error when considering the type and amount of goods allegedly missing, among other things. Furthermore, we may seek appropriate indemnity from the shipper in each claim as may be feasible. In the pending claim for one of the cases, we have received an administrative decision dismissing the claim in its entirety, which remains subject to a mandatory appeal by the Brazil customs authorities. As required to defend such claims, we have made deposits pending resolution of these matters. The balance was $5.1 million as of December 31, 2017 and $5.0 million as of December 31, 2016, and is included in Deferred costs and other assets. We are currently defending these and other Brazilian customs claims and the ultimate disposition of these claims, either individually or in the aggregate, is not expected to materially affect our financial condition, results of operations or cash flows. Accruals As of December 31, 2017, the Company had an accrual of $30.0 million, which was paid in January 2018, related to the U.S. class action settlement that was recorded in 2015. Other We have certain other contingencies incident to the ordinary course of business. Management does not expect the ultimate disposition of such other contingencies to materially affect our financial condition, results of operations or cash flows.

Stock-Based and Long-term Incen

Stock-Based and Long-term Incentive Compensation Plans	12 Months Ended
	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based and Long-term Incentive Compensation Plans	15. Stock-Based and Long-term Incentive Compensation Plans In 2007, our stockholders approved a Long-Term Incentive Plan (the “2007 Plan”). An aggregate of 0.6 million shares of common stock was reserved for issuance to participants under the 2007 Plan. The 2007 Plan provided for stock awards of up to approximately 2.8 million shares of AAWW’s common stock to employees in various forms, including cash awards and performance cash awards. Stock awards included nonqualified options, incentive stock options, share appreciation rights, restricted shares, restricted share units, performance shares and performance units, dividend equivalents and other share-based awards. In 2016, the stockholders approved a revised Long-Term Incentive Plan (the “2016 Plan”), which replaced the 2007 Plan. An aggregate of 0.8 million shares of common stock was reserved for issuance to participants under the 2016 Plan. No new awards have been made under the 2007 Plan since the adoption of the 2016 Plan in May 2016. The portion of the 2016 Plan and the 2007 Plan applicable to employees is administered by the compensation committee of the board of directors, which also establishes the terms of the awards. Awards outstanding under the 2007 Plan will continue to be governed by the terms of that plan and agreements under which they were granted. The 2016 Plan limits the terms of awards to ten years and prohibits the granting of awards more than ten years after the effective date of the 2016 Plan. As of December 31, 2017, the 2016 Plan had a total of 0.5 million shares of common stock available for future award grants to management and members of the board of directors. Including the impact of the change in control as defined under the benefit plan in 2016 (see Note 7), our compensation expense for both plans was $20.9 million in 2017, $30.9 million in 2016 and $15.0 million in 2015 $ million in 2017, $8.7 million in 2016 and $5.7 million in 2015 Nonqualified Stock Options Nonqualified stock options, which have not been granted since 2007, vest over a three- or four-year period and expire seven to ten years from the date of grant. While nonqualified stock options may be granted at any price, they have never been granted with an exercise price less than the fair market value of the stock on the date of grant. A summary of our options as of December 31, 2017 and changes during the year then ended is presented below: Number of Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Outstanding as of December 31, 2016 4,500 $ 58.89 Granted — — Exercised — — Forfeited, net of adjustments (4,500 ) 58.89 Outstanding as of December 31, 2017 — — — — Exercisable as of December 31, 2017 — — — — The total intrinsic value of options exercised in 2016 and 2015 was nominal and the cash received was zero Restricted Share Awards Restricted shares granted vest and are expensed over one-, three- or four- year periods. Restricted share awards have been granted in both shares and units. As of December 31, 2017 Unrecognized December 31, 2017 A summary of our restricted shares as of December 31, 2017 and changes during the year then ended are presented below: Weighted- Average Restricted Share Awards Number of Shares Grant-Date Fair Value Unvested as of December 31, 2016 730,146 $ 39.89 Granted 327,303 54.40 Vested (266,896 ) 38.29 Forfeited (18,396 ) 54.74 Unvested as of December 31, 2017 772,157 $ 44.95 The total fair value of shares vested on various vesting dates was $14.8 million in 2017 in 2016 in 2015 Performance Share and Performance Cash Awards Performance share and performance cash awards granted are expensed over three years, which generally is the requisite service period. Awards generally become vested if (1) we achieve certain specified performance levels compared with predetermined performance thresholds during a three-year period starting in the grant year and ending on December 31 three years later, and (2) the employee remains employed by us through the determination date which can be no later than four months following the end of the Performance Period. Full or partial vesting may occur for certain employee terminations. As a result of a change in control as defined under the benefit plan (see Note 7), the performance levels are deemed to be achieved for all performance share and performance cash awards outstanding as of December 31, 2016. Performance share awards have been granted to employees in shares and units. All performance share and performance cash awards are valued at their fair market value on the date of issuance. The estimated compensation expense recognized for performance share and performance cash awards are net of estimated forfeitures. We assess the performance levels in the first quarter of each year for the prior year. We review the results, adjust the estimated performance level and record any change to compensation cost. As of December 31, 2017, a total of 1.8 million performance shares have been granted. Unrecognized December 31, 2017 A summary of our performance shares as of December 31, 2017 and changes during the year then ended are presented below: Weighted- Average Performance Share Awards Number of Shares Grant-Date Fair Value Unvested as of December 31, 2016 576,166 $ 27.30 Granted 97,205 54.20 Vested (201,324 ) 32.07 Forfeited (17,971 ) 43.03 Unvested as of December 31, 2017 454,076 $ 43.63 The total fair value of shares vested on various vesting dates in 2017 was $10.6 million, $5.8 million in 2016 and $3.7 in 2015. Weighted average grant date fair value was $37.21 in 2016 and $47.48 in 2015.

Profit Sharing, Incentive and R

Profit Sharing, Incentive and Retirement Plans	12 Months Ended
	Dec. 31, 2017
Compensation And Retirement Disclosure [Abstract]
Profit Sharing, Incentive and Retirement Plans	16. Profit Sharing, Incentive and Retirement Plans Profit Sharing and Incentive Plans We have an annual incentive compensation program for management employees. The program provides for payments to eligible employees based upon our financial performance, service performance and attainment of individual performance goals, among other things. In addition, our profit sharing plan allows IBT-represented Atlas crewmembers to receive payments from the plan based upon Atlas’ financial performance. The profit sharing plan is subject to a minimum financial performance threshold. For both plans, we had accruals of $26.9 million as of December 31, 2017 and $22.1 million as of December 31, 2016 in Accrued liabilities. Including the impact of the change in control as defined under the benefit plan in 2016 (see Note 7), we recognized compensation expense associated with both plans totaling $26.9 million in 2017, $21.8 million in 2016 and $28.5 million in 2015. 401(k) and 401(m) Plans Participants in our retirement plan may contribute a portion of their annual compensation to a 401(k) plan on a pretax basis, subject to aggregate limits under the Code. In addition to 401(k) contributions, participants may contribute a portion of their eligible compensation to a 401(m) plan on an after-tax basis. On behalf of participants in the plan who make elective compensation deferrals, we provide a matching contribution subject to certain limitations. Employee contributions in the plan are vested at all times and our matching contributions are subject to a three-year cliff vesting provision, except for employees who are represented by a collective bargaining agreement and are subject to a three-year graded vesting provision. We recognized compensation expense associated with the plan matching contributions totaling $10.9 million in 2017, $10.5 million in 2016 and $9.5

Stock Repurchases

Stock Repurchases	12 Months Ended
	Dec. 31, 2017
Treasury Stock [Abstract]
Stock Repurchases	17. Stock Repurchases We record the repurchase of our shares of common stock at cost based on the settlement date of the transaction. These shares are classified as treasury stock, which is a reduction to stockholders’ equity. Treasury shares are included in authorized and issued shares but excluded from outstanding shares. In 2008, we established a stock repurchase program authorizing the repurchase of up to $100.0 million of our common stock. In November 2013, we announced an increase of $51.0 million to our stock repurchase program. As of December 31, 2017, we had repurchased a total of 3,307,911 shares of our common stock for approximately $126.0 million under this program, resulting in $25.0 million of available authorization remaining. Purchases may be made at our discretion in the form of open market repurchase programs, privately negotiated transactions, accelerated share repurchase programs or a combination of these methods. The actual timing and amount of our repurchases will depend on Company and market conditions. In addition, we repurchased 195,831 and 297,569 shares of common stock from management, in connection with the vesting of equity awards to pay the statutory tax withholdings of employees, at an average price of $54.20 per share in 2017 in 2016,

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Share	18. Earnings Per Share Basic earnings per share (“EPS”) represents income divided by the weighted average number of common shares outstanding during the measurement period. Diluted EPS represents income divided by the weighted average number of common shares outstanding during the measurement period while also giving effect to all potentially dilutive common shares that were outstanding during the period using the treasury stock method. The calculations of basic and diluted EPS were as follows: For the Years Ended December 31, Numerator: 2017 2016 2015 Income from continuing operations, net of taxes $ 224,338 $ 42,625 $ 7,286 Denominator: Basic EPS weighted average shares outstanding 25,241 24,843 24,833 Effect of dilutive convertible notes 27 - - Effect of dilutive stock options and restricted stock 586 277 185 Diluted EPS weighted average shares outstanding 25,854 25,120 25,018 Earnings per share from continuing operations: Basic $ 8.89 $ 1.72 $ 0.29 Diluted $ 8.68 $ 1.70 $ 0.29 Loss per share from discontinued operations: Basic $ (0.03 ) $ (0.04 ) $ - Diluted $ (0.03 ) $ (0.04 ) $ - Earnings per share: Basic $ 8.85 $ 1.67 $ 0.29 Diluted $ 8.64 $ 1.65 $ 0.29 Anti-dilutive shares related to warrants and stock options that were out of the money and excluded for 2017 were 7.8 million, 2016 were 3.3 million and 2015 were 3.0 million. Diluted shares reflect the potential dilution that could occur from stock options and restricted shares using the treasury stock method. The calculation of EPS does not include restricted share units and warrants in which performance or market conditions were not satisfied of 6.8 million in 2017, 7.5 million in 2016 and 0.3 million in 2015.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2017
Accumulated Other Comprehensive Income Loss [Abstract]
Accumulated Other Comprehensive Income (Loss)	19. Accumulated Other Comprehensive Income (Loss) The following table summarizes t he components of Accumulated other comprehensive income (loss): Interest Rate Foreign Currency Derivatives Translation Total Balance as of December 31, 2015 $ (6,072 ) $ 9 $ (6,063 ) Reclassification to interest expense 1,770 - 1,770 Tax effect (700 ) - (700 ) Balance as of December 31, 2016 (5,002 ) 9 (4,993 ) Reclassification to interest expense 1,621 - 1,621 Tax effect (621 ) - (621 ) Balance as of December 31, 2017 $ (4,002 ) $ 9 $ (3,993 ) Interest Rate Derivatives As of December 31, 2017, there was $6.5 million of unamortized net realized loss before taxes remaining in Accumulated other comprehensive income (loss) related to terminated forward-starting interest rate swaps, which had been designated as cash flow hedges to effectively fix the interest rates on two 747-8F financings in 2011 and three 777-200LRF financings in 2014. The net loss is amortized and reclassified into Interest expense over the remaining life of the related debt. Net realized losses reclassified into earnings were $1.6 million and $1.8 million for 2017 and 2016, respectively. Net realized losses expected to be reclassified into earnings within the next 12 months are $1.5 million as of December 31, 2017.

Selected Quarterly Financial In

Selected Quarterly Financial Information (unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure Abstract
Selected Quarterly Financial Information (unaudited)	20. Selected Quarterly Financial Information (unaudited) The following tables summarize the 2017 and 2016 quarterly results: First Second Third Fourth 2017* Quarter Quarter Quarter Quarter Total Operating Revenue $ 475,394 $ 517,366 $ 535,748 $ 627,952 Operating Income 24,036 58,478 52,712 106,748 Income (Loss) from continuing operations, net of taxes 35 39,044 (24,195 ) 209,454 Income (Loss) from discontinued operations, net of taxes (787 ) (105 ) 33 (6 ) Net Income (Loss) $ (752 ) $ 38,939 $ (24,162 ) $ 209,448 Earnings (Loss) per share from continuing operations: Basic $ 0.00 $ 1.55 $ (0.96 ) $ 8.28 Diluted** $ 0.00 $ 0.92 $ (0.96 ) $ 6.71 Loss per share from discontinued operations: Basic $ (0.03 ) $ (0.00 ) $ 0.00 $ (0.00 ) Diluted $ (0.03 ) $ (0.00 ) $ 0.00 $ (0.00 ) Earnings (Loss) per share: Basic $ (0.03 ) $ 1.54 $ (0.96 ) $ 8.28 Diluted** $ (0.03 ) $ 0.92 $ (0.96 ) $ 6.71 First Second Third Fourth 2016*** Quarter Quarter Quarter Quarter Total Operating Revenue $ 418,615 $ 443,272 $ 448,015 $ 529,725 Operating Income 20,057 20,824 25,998 101,432 Income (Loss) from continuing operations, net of taxes 471 20,919 (7,501 ) 28,736 Loss from discontinued operations, net of taxes - (345 ) (445 ) (319 ) Net Income (Loss) $ 471 $ 20,574 $ (7,946 ) $ 28,417 Earnings (Loss) per share from continuing operations: Basic $ 0.02 $ 0.84 $ (0.30 ) $ 1.15 Diluted**** $ 0.02 $ (0.26 ) $ (0.30 ) $ 1.12 Loss per share from discontinued operations: Basic $ - $ (0.01 ) $ (0.02 ) $ (0.01 ) Diluted $ - $ (0.01 ) $ (0.02 ) $ (0.01 ) Earnings (Loss) per share: Basic $ 0.02 $ 0.83 $ (0.32 ) $ 1.14 Diluted**** $ 0.02 $ (0.28 ) $ (0.32 ) $ 1.11 * Included in the first, second and third quarters were an unrealized loss on financial instruments of $5.2 million, an unrealized gain on financial instruments of $13.8 million and an unrealized loss on financial instruments of $44.8 million, respectively. Included in the fourth quarter was an income tax benefit of $130.0 million related to the U.S. Tax Cuts and Jobs Act (see Note 11) and an unrealized gain on financial instruments of $23.7 million. ** In 2017, the sum of quarterly diluted EPS amounts differs from the full year diluted EPS. The difference primarily relates to the exclusion from the calculation of diluted EPS of unrealized gains on financial instruments in the second and fourth quarters, and anti-dilutive shares in the third quarter, both related to the Amazon Warrant *** Included in the first quarter was **** In 2016, the sum of quarterly diluted EPS amounts differs from the full year diluted EPS. The difference primarily relates to the exclusion from the calculation of diluted EPS of an unrealized gain on financial instruments in the second quarter and anti-dilutive shares in the third quarter, both related to the Amazon Warrant.

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2017
Valuation And Qualifying Accounts [Abstract]
Valuation and Qualifying Accounts	Schedule II—Valuation and Qualifying Accounts (in thousands) Additions Description Balance at Beginning of Period Charged to Costs and Expenses Deductions, net of recoveries Balance at End of Period For the Year ended December 31, 2017 Allowances deducted in the balance sheet from the assets to which they apply: Allowance for doubtful accounts $ 997 $ 198 $ 299 $ 1,494 For the Year ended December 31, 2016 Allowances deducted in the balance sheet from the assets to which they apply: Allowance for doubtful accounts $ 1,247 $ 508 $ (758 ) $ 997 For the Year ended December 31, 2015 Allowances deducted in the balance sheet from the assets to which they apply: Allowance for doubtful accounts $ 1,658 $ 171 $ (582 ) $ 1,247

Summary of Significant Accoun30

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Use of Estimates Policy	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires us to make estimates and judgments that affect the amounts reported in these financial statements and the related disclosures. Actual results may differ from those estimates. Estimates are used in determining, among other items, asset lives and residual values, cash flows for impairment analysis, heavy maintenance costs, income tax accounting, business combinations, intangible assets, warrants,
Revenue Recognition Policy	Revenue Recognition Revenue from ACMI and CMI contracts is typically recognized as the block hours are operated on behalf of a customer during a given month, as defined contractually, based on flight departure. The time interval between when an aircraft departs the terminal until it arrives at the destination terminal is measured in hours and called a “Block Hour”. If a customer flies below a minimum contracted Block Hour guarantee, the contracted minimum revenue amounts are recognized as revenue. We recognize revenue for Charter upon flight departure. We record Dry Lease rental income on a straight-line basis over the term of the operating lease. In limited cases, leases provide for additional rentals based on usage, which is recorded as revenue as it is earned under the terms of the lease. Usage is calculated based on hourly usage or number of flights operated, depending on the lease agreement, and is typically reported monthly by the lessee. Customer maintenance reserves are amounts received under our Dry Leases that are subject to reimbursement to the lessee upon the completion of qualifying maintenance work on the specific Dry Leased aircraft and are included in Accrued liabilities. We defer revenue recognition until the end of the lease, when we are able to finalize the amount, if any, to be reimbursed to the customer. The Company recognizes revenue for management and administrative support services when the services are provided.
Cash and Cash Equivalents Policy	Cash and Cash Equivalents Cash and cash equivalents include cash on hand, demand deposits and other cash investments that are highly liquid in nature and have original maturities of three months or less at acquisition.
Short-Term Investments Policy	Short-term Investments Short-term investments are primarily comprised of certificates of deposit, current portions of debt securities and money market funds.
Restricted Cash Policy	Restricted Cash Cash that is restricted under secured aircraft debt agreements, whereby it can only be used to make principal and interest payments on the related debt secured by those aircraft, is classified as Restricted cash.
Accounts Receivable Policy	Accounts Receivable We perform a monthly evaluation of our accounts receivable and establish an allowance for doubtful accounts based on our best estimate of probable credit losses resulting from the inability or unwillingness of our customers to make required payments. Account balances are charged off against the allowance when we determine that the receivable will not be recovered.
Escrow Deposits and Letters of Credit Policy	Escrow Deposits and Letters of Credit We had $5.1 million as of December 31, 2017 and $5.0 million as of December 31, 2016, for certain deposits required in the normal course of business for various items including, but not limited to, surety and customs bonds, airfield privileges, judicial deposits, insurance and cash pledged under standby letters of credit related to collateral. These amounts are included in Deferred costs and other assets.
Expendable Parts Policy	Expendable Parts Expendable parts, materials and supplies for flight equipment are carried at average acquisition costs and are included in Prepaid expenses and other current assets. When used in operations, they are charged to maintenance expense. Allowances for excess and obsolescence for expendable parts expected to be on hand at the date aircraft are retired from service are provided over the estimated useful lives of the related airframes and engines. These allowances are based on management estimates, which are subject to change as conditions in the business evolve. The net book value of expendable parts inventory was $34.7 million as of December 31, 2017 and $24.2 million at December 31, 2016, net of allowances for obsolescence of $27.8 million at December 31, 2017 and $22.3 million at December 31, 2016.
Property and Equipment Policy	Property and Equipment We record property and equipment at cost and depreciate these assets to their estimated residual values on a straight-line basis over their estimated useful lives or average remaining fleet lives. We review these assumptions at least annually and adjust depreciation on a prospective basis. Expenditures for major additions, improvements and flight equipment modifications are generally capitalized and depreciated over the shorter of the estimated life of the improvement, the modified assets’ remaining life or remaining lease term. Most of our flight equipment is specifically pledged as collateral for our indebtedness. The estimated useful lives of our property and equipment are as follows: Range Flight equipment 30 to 40 years Computer software and equipment 3 to 5 years Ground handling equipment and other 3 to 5 years Depreciation expense related to property and equipment was $153.1 million in 2017, $141.5 million in 2016 and $122.2 million in 2015. The net book value of flight equipment on dry lease to customers was $1,270.7 million as of December 31, 2017 and $936.0 million as of December 31, 2016. The accumulated depreciation for flight equipment on dry lease to customers was $152.7 million as of December 31, 2017 and $99.8 million as of December 31, 2016. Rotable parts are recorded in Property and equipment, net, and are depreciated over their average remaining fleet lives and written off when they are determined to be beyond economic repair. The net book value of rotable parts inventory was $184.8 million as of December 31, 2017 and $142.7 million as of December 31, 2016.
Capitalized Interest on Flight Equipment Modifications in Progress Policy	Capitalized Interest on Flight Equipment Modifications in Progress Interest on funds used to finance the acquisition of flight equipment up to the date the asset is ready for its intended use is capitalized and included in the cost of the asset. Included in capitalized interest is the interest paid on the purchase deposit borrowings directly associated with the acquisition of flight equipment. The remainder of capitalized interest recorded on the acquisition of flight equipment is determined by taking the weighted average cost of funds associated with our other debt and applying it against the amounts paid as purchase deposits.
Goodwill Policy	Goodwill Goodwill represents the excess of an acquisition’s purchase price over the fair value of the identifiable net assets acquired and liabilities assumed. Goodwill is not amortized, but tested for impairment annually during the fourth quarter of each year, or more frequently if certain events or circumstances indicate that an impairment loss may have been incurred. Goodwill is not deductible for tax purposes. We may elect to perform a qualitative analysis on the reporting unit that has goodwill to determine whether it is more likely than not that fair value of the reporting unit is less than its carrying value. If the qualitative analysis indicates that it is more likely than not that the fair value of a reporting unit is less than its carrying amount, or if we elect not to perform a qualitative analysis, we perform a quantitative analysis to determine whether a goodwill impairment exists. If the goodwill’s carrying value exceeds its implied fair value calculated using the quantitative approach, an impairment charge is recorded for the difference. Fair value is determined using a discounted cash flow analysis based on key assumptions including, but not limited to, (i) a projection of revenues, expenses and other cash flows; (ii) terminal period revenue growth and cash flows; and (iii) an assumed discount rate. The total amount of goodwill was $40.4 million, which is included in Intangible assets, net and goodwill in the consolidated balance sheets as of December 31, 2017 and 2016 (see Notes 4 and 6). During the fourth quarter of 2017, we performed a qualitative analysis and determined that goodwill was not impaired.
Impairment of Long-Lived Assets Policy	Impairment of Long-Lived Assets We record impairment charges on long-lived assets when events and circumstances indicate that the assets may be impaired, the undiscounted cash flows estimated to be generated by those assets are less than the associated carrying amount and the net book value of the assets exceeds the associated estimated fair value. For flight equipment and finite-lived intangibles used in our ACMI and Charter segments, assets are grouped at the operating fleet level for impairment testing. For flight equipment and finite-lived intangibles used in our Dry Leasing segment, assets are tested on an individual basis for impairment. For assets classified as held for sale, an impairment is recognized when the fair value less the cost to sell the asset is less than its carrying amount. In developing estimates for flight equipment and cash flows, we use external appraisals and other industry data for the various equipment types, anticipated utilization of the assets, revenue generated, associated costs and length of service.
Long Term Investments Policy	Long-term Investments Long-term investments consist of debt securities, including accrued interest, for which management has the intent and ability to hold to maturity. These investments are classified as held-to-maturity and are reported at amortized cost. Interest on debt securities and accretion of discounts using the effective interest method are included in Interest income.
Variable Interest Entities and Off-Balance-Sheet Arrangements Policy	Variable Interest Entities and Off-Balance Sheet Arrangements We hold a 50% interest in GATS GP (BVI) Ltd. (“GATS”), a joint venture with an unrelated third party. The purpose of the joint venture is to purchase rotable parts and provide repair services for those parts, primarily for our 747-8F aircraft. The joint venture is a . Our investment in GATS was $22.1 million as of December 31, 2017 and $22.2 million as of December 31, 2016 and our maximum exposure to losses from the entity is limited to our investment, which is composed primarily of rotable inventory parts. GATS does not have any third-party debt obligations. We had Accounts payable to GATS of $ million as of December 31, 2017 and $ million as of December 31, 2016. A portion of our operating aircraft are owned or effectively owned and leased through trusts established specifically to purchase, finance and lease aircraft to us. We have not consolidated any aircraft in the related trusts because we are not the primary beneficiary. Our maximum exposure under these operating leases is the remaining lease payments, which amounts are reflected in the future lease commitments more fully described in Note 10.
Income Taxes Policy	Income Taxes Deferred income taxes are recognized for the tax consequences of reporting items in our income tax returns at different times than the items are reflected in our financial statements. These temporary differences result in deferred tax assets and liabilities that are calculated by applying enacted statutory tax rates applicable to future years to differences between the financial statement carrying amounts and the tax bases of existing assets and liabilities. If necessary, deferred income tax assets are reduced by a valuation allowance to an amount that is determined to be more likely than not recoverable. We must make significant estimates and assumptions about future taxable income and future tax consequences when determining the amount, if any, of the valuation allowance. We have recorded reserves for income taxes that may become payable in future years. Although management believes that its positions taken on income tax matters are reasonable, we have nevertheless established tax reserves in recognition that various taxing authorities may challenge certain of the positions taken by us, potentially resulting in additional liabilities for taxes. In accordance with recently issued SEC guidance to address the accounting for income tax reform, and based on our interpretation of the U.S. Tax Cuts and Jobs Act, we have recorded provisional income tax benefits in connection with the remeasurement of our U.S. net deferred tax liability. We have not recorded any provisional amount in connection with the one-time deemed repatriation tax on unremitted foreign earnings (see Note 11). The ultimate impact of the U.S. Tax Cuts and Jobs Act may differ from the provisional amounts reflected in our consolidated financial statements due to additional regulatory guidance that may be issued, changes in interpretations and assumptions, additional analysis, and actions we may take as a result. We expect to update these provisional amounts as the analysis is finalized within the one-year measurement period.
Heavy Maintenance Policy	Heavy Maintenance Except for engines used on our 747-8F aircraft, we account for heavy maintenance costs for airframes and engines used in our ACMI and Charter segments using the direct expense method. Under this method, heavy maintenance costs are charged to expense upon induction, based on our best estimate of the costs. We account for heavy maintenance costs for airframes and engines used in our Dry Leasing segment and engines used on our 747-8F aircraft using the deferral method. Under this method, we defer the expense recognition of scheduled heavy maintenance events, which are amortized over the estimated period until the next scheduled heavy maintenance event is required. Amortization of deferred maintenance expense is included in Depreciation and amortization. The following table provides a summary of Deferred maintenance included within Deferred costs and other assets as of December 31: 2017 2016 Beginning balance, net $ 19,100 $ - Deferred maintenance costs 50,675 19,644 Amortization of deferred maintenance (5,907 ) (544 ) Ending balance, net $ 63,868 $ 19,100
Prepaid Maintenance Deposits Policy	Prepaid Maintenance Deposits Certain of our aircraft financing agreements require security deposits to our finance providers to ensure that we perform major maintenance as required. These are substantially refundable to us and are, therefore, accounted for as deposits and included in Prepaid maintenance and in Deferred costs and other assets. Such amounts were $37.3 million as of December 31, 2017 and $53.4 million at December 31, 2016.
Foreign Currency Policy	Foreign Currency While most of our revenues are denominated in U.S. dollars, our results of operations may be exposed to the effect of fluctuations in the U.S. dollar value of foreign currency-denominated operating revenues and expenses. Our largest exposures come from the Brazilian real. We do not currently have a foreign currency hedging program related to our foreign currency-denominated transactions. Gains or losses resulting from foreign currency transactions are included within Non-operating Expenses (Income).
Stock-Based Compensation Policy	Stock-Based Compensation We have various stock-based compensation plans for certain employees and outside directors, which are described more fully in Note 15. We recognize based on the fair value on grant date We estimate option and restricted stock unit forfeitures at the time of grant and periodically revise those estimates in subsequent periods if actual forfeitures differ from those estimates. As a result, we record stock-based compensation expense only for those awards that are expected to vest.
Legal and Regulatory Matters Policy	Legal and Regulatory Matters We are party to legal and regulatory proceedings with respect to a variety of matters. We evaluate the likelihood of an unfavorable outcome of these proceedings each quarter. Our judgments are subjective and are based on the status of the legal or regulatory proceedings, the merits of our defenses and consultation with legal counsel. Due to the inherent uncertainties of the legal and regulatory proceedings in the multiple jurisdictions in which we operate, our judgments may be different from the actual outcomes.
Supplemental Cash Flow Information	Supplemental Cash Flow Information Cash interest paid to lenders is calculated on the face amount of our various debt instruments based on the contractual interest rates in effect during each payment period. The following table summarizes interest and income taxes paid: 2017 2016 2015 Interest paid $ 73,872 $ 66,306 $ 75,135 Income taxes paid, net of refunds $ 563 $ 1,160 $ (228 ) The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total shown in the consolidated statements of cash flows: 2017 2016 Cash and cash equivalents $ 280,809 $ 123,890 Restricted cash 11,055 14,360 Total Cash, cash equivalents and restricted cash shown in consolidated statements of cash flows $ 291,864 $ 138,250
Recent Accounting Pronouncements	Recent Accounting Pronouncements In March 2016, the Financial Accounting Standards Board (“FASB”) amended its accounting guidance for share-based compensation. The amended guidance changes how companies account for certain aspects of share-based payment awards to employees, including the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. We adopted this amended guidance on January 1, 2017 on a prospective basis. As a result, we recognized $1.9 million of excess tax benefits during the year ended December 31, 2017 as a reduction of income tax expense in our consolidated statements of operations. Excess tax benefits were previously recognized within equity. Additionally, our consolidated statements of cash flows present such excess tax benefits, which were previously presented as a financing activity, as an operating activity. In February 2016, the FASB amended its accounting guidance for leases. The guidance requires a lessee to recognize assets and liabilities on the balance sheet arising from leases with terms greater than 12 months. While lessor accounting guidance is relatively unchanged, certain amendments were made to conform with changes made to lessee accounting and the amended revenue recognition guidance. The new guidance will continue to classify leases as either finance or operating, with classification affecting the presentation and pattern of expense and income recognition, in the statement of operations. It also requires additional quantitative and qualitative disclosures about leasing arrangements. The amended guidance is effective as of the beginning of 2019, with early adoption permitted. While we are still assessing the impact the amended guidance will have on our financial statements, we expect that recognizing the right-of-use asset and related lease liability will impact our balance sheet materially. We plan to adopt the new guidance on its required effective date of January 1, 2019 In May 2014, the FASB amended its accounting guidance for revenue recognition. Subsequently, the FASB has issued several clarifications and updates. The fundamental principles of the new guidance are that companies should recognize revenue in a manner that reflects the timing of the transfer of services to customers and consideration that a company expects to receive for the services provided. It also requires additional disclosures necessary for the financial statement users to understand the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. The two permitted transition methods under the guidance are the full retrospective approach, under which the guidance is applied to all periods presented, or the modified retrospective approach, under which the guidance is applied only to the most current period presented. We adopted this amended guidance on January 1, 2018 using the modified retrospective approach and we do not believe it will have a material effect on our financial statements. As a result of adoption, revenue recognized under previous guidance based on flight departure will be recognized over time as the services are performed. In addition, revenue under certain ACMI and CMI contracts, such as revenue related to contracted minimum block hour guarantees, will be recognized in later periods, and some revenue adjustments related to meeting or exceeding on-time performance targets will be recognized in earlier periods.

Summary of Significant Accoun31

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2017
Summary Of Significant Accounting Policies Tables [Abstract]
Estimated Useful Lives of Property and Equipment	Range Flight equipment 30 to 40 years Computer software and equipment 3 to 5 years Ground handling equipment and other 3 to 5 years
Schedule of Deferred Maintenance	The following table provides a summary of Deferred maintenance included within Deferred costs and other assets as of December 31: 2017 2016 Beginning balance, net $ 19,100 $ - Deferred maintenance costs 50,675 19,644 Amortization of deferred maintenance (5,907 ) (544 ) Ending balance, net $ 63,868 $ 19,100
Supplemental Cash Flow Information	The following table summarizes interest and income taxes paid: 2017 2016 2015 Interest paid $ 73,872 $ 66,306 $ 75,135 Income taxes paid, net of refunds $ 563 $ 1,160 $ (228 )
Reconciliation of Cash, Cash Equivalents and Restricted Cash	The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total shown in the consolidated statements of cash flows: 2017 2016 Cash and cash equivalents $ 280,809 $ 123,890 Restricted cash 11,055 14,360 Total Cash, cash equivalents and restricted cash shown in consolidated statements of cash flows $ 291,864 $ 138,250

DHL Investment and Polar (Table

DHL Investment and Polar (Tables)	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
Summary of Aircraft Types, Services and Number of Aircraft Provided to DHL	The following table summarizes the aircraft types, services and number of aircraft provided to DHL as of December 31, 2017: Aircraft Service Total 747-8F ACMI 6 747-400F ACMI 8 777-200LRF CMI 5 767-300 CMI and Dry Leasing 4 767-200 CMI 9 737-400F CMI 5 757-200F Dry Leasing 1 Total 38
Summary of Transactions with Polar	The following table summarizes our transactions with Polar: Revenue and Expenses: 2017 2016 2015 Revenue from Polar $ 420,564 $ 407,891 $ 399,113 Ground handling and airport fees to Polar 2,746 1,667 2,019 Accounts receivable/payable as of December 31: 2017 2016 Receivables from Polar $ 9,558 $ 8,161 Payables to Polar 2,751 2,019 Aggregate Carrying Value of Polar Investment as of December 31: 2017 2016 Aggregate Carrying Value of Polar Investment $ 4,870 $ 4,870

Southern Air Acquisition (Table

Southern Air Acquisition (Tables)	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Schedule of Business Acquisition Consideration	Total consideration for Southern Air was $105.8 million, net of cash acquired, and consisted of the following: Fair value of consideration Cash paid, net of $15,615 cash acquired $ 107,498 Working capital adjustment (2,106 ) Other adjustments 372 Total consideration $ 105,764
Schedule of Amounts Recognized for Fair Values of Assets Acquired and Liabilities Assumed	The following table summarizes the amounts recognized for fair values of the assets acquired and liabilities assumed: Estimated Fair Value Accounts receivable, net $ 22,912 Prepaid expenses and other current assets 2,434 Property and equipment 6,355 Intangible assets and goodwill 67,341 Deferred income taxes, net 36,452 Other assets 1,498 Total assets acquired $ 136,992 Accounts payable and accrued liabilities $ 31,228 Total liabilities assumed 31,228 Net assets acquired $ 105,764
Schedule of Fair Values and Initial Useful Lives Assigned to Intangible Assets and Goodwill	The fair values and initial useful lives assigned to all intangible assets and goodwill are as follows: Estimated Useful Lives Estimated Fair Value Customer relationship 16 years $ 26,280 Trade name 1.5 years 700 Goodwill Indefinite 40,361 Total intangible assets and goodwill $ 67,341
Summary of Employee Termination Benefit Liabilities	A summary of the employee termination benefit liabilities, which are expected to be paid by the first quarter of 2018, is as follows: 2017 2016 Beginning balance $ 1,214 $ 3,797 Wind-down expenses 1,990 - Cash payments (3,133 ) (2,583 ) Ending balance $ 71 $ 1,214

Intangible Assets, Net and Go34

Intangible Assets, Net and Goodwill (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets, Net and Goodwill	The following table presents our Intangible assets, net and goodwill as of December 31: 2017 2016 Goodwill $ 40,361 $ 40,361 Fair value adjustments on operating leases 45,531 45,531 Lease intangible 54,891 57,203 Customer relationship 26,280 26,280 Trade name 700 700 Less: accumulated amortization (61,278 ) (54,046 ) $ 106,485 $ 116,029
Schedule of Estimated Future Amortization Expense of Intangible Assets	The estimated future amortization expense of intangible assets as of December 31, 2017 is as follows: 2018 $ 8,792 2019 8,094 2020 8,047 2021 8,547 2022 8,862 Thereafter 23,782 Total $ 66,124

Amazon (Tables)

Amazon (Tables)	12 Months Ended
	Dec. 31, 2017
Warrants And Rights Note Disclosure [Abstract]
Summary of the Customer Incentive Asset	The following table provides a summary of the customer incentive asset as of December 31: 2017 2016 Beginning balance $ 92,351 $ - Initial value for vested portion of warrant 19,448 92,888 Amortization of customer incentive asset (5,261 ) (537 ) Ending balance $ 106,538 $ 92,351

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Accrued Liabilities Current And Noncurrent [Abstract]
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following as of December 31: 2017 2016 Maintenance $ 156,042 $ 54,495 Customer maintenance reserves 89,037 81,830 Salaries, wages and benefits 65,546 55,063 U.S. class action settlement 30,000 35,000 Aircraft fuel 22,196 16,149 Deferred revenue 20,986 10,298 Other 71,036 68,052 Accrued liabilities $ 454,843 $ 320,887

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Obligations	Our debt obligations, as of December 31: 2017 2016 Range of Maturity Dates Interest Rates (1) Balance Interest Rates (1) Balance Ex-Im Guaranteed Notes 2021 to 2025 1.89% $ 564,184 1.89% $ 645,537 Term loans and capital leases 2020 to 2032 4.16% 1,145,116 4.34% 1,053,273 Private Placement Facility 2025 to 2026 3.17% 144,539 - - Convertible Notes 2022 to 2024 2.04% 513,500 2.25% 224,500 EETC 2019 7.52% 11,480 7.52% 20,084 Total principal amount of debt and capital leases 2,378,819 1,943,394 Less: unamortized debt discount and issuance costs (151,820 ) (91,983 ) Total debt 2,226,999 1,851,411 Less current portion of debt and capital leases (218,013 ) (184,748 ) Long-term debt $ 2,008,986 $ 1,666,663 (1) Interest rates reflect weighted-average rates as of year-end.
Schedule of Convertible Notes	The convertible notes consisted of the following as of December 31: 2017 2016 2017 Convertible Notes 2015 Convertible Notes 2015 Convertible Notes Remaining life in months 77 53 65 Liability component: Gross proceeds $ 289,000 $ 224,500 $ 224,500 Less: debt discount, net of amortization (65,187 ) (36,108 ) (42,956 ) Less: debt issuance cost, net of amortization (5,216 ) (3,445 ) (4,146 ) Net carrying amount $ 218,597 $ 184,947 $ 177,398 Equity component (1) $ 70,140 $ 52,903 $ 52,903 (1) Included in Additional paid-in capital on the consolidated balance sheets.
Summary of Convertible Note Hedges and Related Warrants	The following table summarizes the convertible note hedges and related warrants: 2017 Convertible Note 2015 Convertible Note Convertible Note Hedges: Number of shares (1) 4,731,306 3,031,558 Initial price per share $ 61.08 $ 74.05 Cost of hedge $ 70,140 $ 52,903 Convertible Note Warrants: Number of shares (1) 4,731,306 3,031,558 Initial price per share $ 92.20 $ 95.01 Proceeds from sale of warrants $ 38,148 $ 36,290 (1)
Summary of Interest Expense Recognized	The following table presents the amount of interest expense recognized related to the 2017 Convertible Notes and the 2015 Convertible Notes: For the Year Ended December 31, 2017 December 31, 2016 Contractual interest coupon $ 8,348 $ 5,051 Amortization of debt discount 11,801 6,421 Amortization of debt issuance costs 1,132 677 Total interest expense recognized $ 21,281 $ 12,149
Schedule of Future Cash Payments for Debt	The following table summarizes the cash required to be paid by year and the carrying value 2018 $ 230,464 2019 230,537 2020 343,624 2021 238,223 2022 426,789 Thereafter 909,182 Total debt cash payments 2,378,819 Less: unamortized debt discount and issuance costs (151,820 ) Debt $ 2,226,999
Term Loans and Capital Lease [Member]
Terms And Balances For Financing	The following table summarizes the terms for each term loan entered into during 2017 (in millions): Issue Face Collateral Original Fixed Interest Date Value Type Term Rate First 2017 Term Loan April 2017 $ 20.1 767-300 91 months 3.02% Second 2017 Term Loan April 2017 21.3 767-300 91 months 3.16% Third 2017 Term Loan May 2017 21.5 767-300 91 months 3.16% Fourth 2017 Term Loan June 2017 21.3 767-300 91 months 3.09% Fifth 2017 Term Loan June 2017 21.7 767-300 91 months 3.11% Sixth 2017 Term Loan June 2017 21.7 767-300 91 months 3.11% Seventh 2017 Term Loan June 2017 18.7 None 58 months 2.17% Eighth 2017 Term Loan July 2017 12.5 767-300 60 months 3.62% Ninth 2017 Term Loan Nov 2017 26.9 None 60 months 2.38% Total $ 185.7
Private Placement Facility [Member]
Terms And Balances For Financing	The following table summarizes the terms for each financing entered into during 2017 under the Private Placement Facility (in millions): Issue Face Collateral Original Fixed Interest Date Value Type Term Rate First 2017 Equipment Note Oct 2017 $ 21.2 Dry Lease and 767-300 87 months 2.93% First 2017 Equipment Term Loan Oct 2017 2.6 Dry Lease and 767-300 103 4.75% Second 2017 Equipment Note Oct 2017 21.4 Dry Lease and 767-300 88 months 2.93% Second 2017 Equipment Term Loan Oct 2017 3.2 Dry Lease and 767-300 107 months 4.75% Third 2017 Equipment Note Oct 2017 21.2 Dry Lease and 767-300 87 months 2.93% Third 2017 Equipment Term Loan Oct 2017 3.0 Dry Lease and 767-300 105 months 4.75% Fourth 2017 Equipment Note Dec 2017 21.2 Dry Lease and 767-300 88 months 2.93% Fourth 2017 Equipment Term Loan Dec 2017 2.9 Dry Lease and 767-300 104 4.87% Fifth 2017 Equipment Note Dec 2017 21.4 Dry Lease and 767-300 89 months 2.93% Fifth 2017 Equipment Term Loan Dec 2017 3.2 Dry Lease and 767-300 107 months 4.87% Sixth 2017 Equipment Note Dec 2017 21.4 Dry Lease and 767-300 88 months 2.93% Sixth 2017 Equipment Term Loan Dec 2017 3.1 Dry Lease and 767-300 106 months 4.94% Total $ 145.8
Convertible Notes [Member]
Schedule of Convertible Notes	The following table lists certain key terms for the Convertible Notes: 2017 Convertible Note 2015 Convertible Note Fixed interest rate 1.88 % 2.25 % Earliest conversion date September 1, 2023 September 1, 2021 Initial conversion price per share $ 61.08 $ 74.05 Conversion rate (shares for each $1,000 of principal) 16.3713 13.5036

Commitments (Tables)

Commitments (Tables)	12 Months Ended
	Dec. 31, 2017
Leases And Aircraft Purchase Commitments Tables [Abstract]
Summary of Rental Expenses	The following table summarizes rental expenses in: 2017 2016 2015 Aircraft and engines $ 142,945 $ 146,110 $ 145,031 Purchased capacity, office, vehicles and other $ 46,817 $ 23,727 $ 44,228
Summary of Minimum Annual Rental Commitments	The following table summarizes our minimum annual rental commitments as of the periods indicated under non-cancelable aircraft, engine, real estate and other operating leases with initial or remaining terms of more than one year, reflecting the terms that were in effect as of December 31, 2017: Aircraft and Engine Other Operating Operating Leases Leases Total 2018 $ 138,223 $ 7,003 $ 145,226 2019 154,461 6,466 160,927 2020 149,214 5,908 155,122 2021 157,985 4,680 162,665 2022 111,064 1,843 112,907 Thereafter 109,993 27 110,020 Total minimum rental payments $ 820,940 $ 25,927 $ 846,867
Summary of Contractual Amount of Minimum Dry Lease Income	The following table summarizes the contractual amount of minimum income under Dry Leases and the non-cancelable aircraft subleases, reflecting the terms that were in effect as of December 31, 2017: Dry Lease Sublease Income Income Total 2018 $ 139,663 $ 52,800 $ 192,463 2019 127,597 - 127,597 2020 117,222 - 117,222 2021 98,668 - 98,668 2022 95,424 - 95,424 Thereafter 219,033 - 219,033 Total minimum lease receipts $ 797,607 $ 52,800 $ 850,407

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Components of the Provision for Income Taxes	A reconciliation of the provision (benefit) for income taxes applying the statutory federal income tax rate of 35.0% for each of the years ended December 31, is as follows: 2017 2016 2015 Current: Federal $ (133 ) $ (376 ) $ 52 State and local (99 ) (298 ) 48 Foreign 596 84 1,292 Total current expense 364 (590 ) 1,392 Deferred: Federal (87,185 ) 46,391 (24,425 ) State and local 1,868 (1,436 ) (3,531 ) Foreign 3,987 2,426 2,058 Total deferred expense (benefit) (81,330 ) 47,381 (25,898 ) Total income tax expense (benefit) $ (80,966 ) $ 46,791 $ (24,506 )
Domestic and Foreign Earnings before Income Taxes	The domestic and foreign earnings before income taxes are as follows: 2017 2016 2015 Domestic $ 104,321 $ 61,006 $ (57,825 ) Foreign 39,051 28,410 40,605 Income (loss) before income taxes $ 143,372 $ 89,416 $ (17,220 )
Effective Income Tax Rate Reconciliation	A reconciliation of differences between the U.S. federal statutory income tax rate and the effective income tax rates is presented as a percent of expense (benefit) as follows: 2017 2016 2015 U.S. federal statutory income tax rate 35.0 % 35.0 % (35.0 %) State and local taxes based on income, net of federal benefit 0.3 % 1.10 % (2.0 %) Change in deferred foreign and state tax rates 0.6 % (2.2 %) (12.0 %) Nondeductible customer incentive related to Amazon 5.0 % 10.9 % 0.0 % Nondeductible compensation expenses related to Amazon — 13.0 % 0.0 % Other nondeductible expenses 1.4 % 4.3 % 10.2 % Extraterritorial income tax benefit — — (23.3 %) Tax incentives and additional deductions (0.6 %) (0.9 %) (4.9 %) Favorable resolution of income tax issues — — (13.8 %) Tax effect of foreign operations (7.7 %) (9.4 %) (66.4 %) Impact of U.S. Tax Cuts and Jobs Act (90.7 %) — — Other 0.2 % 0.5 % 4.9 % Effective income tax rate (56.5 %) 52.3 % (142.3 %)
Deferred Tax Assets (Liabilities)	The net noncurrent deferred tax asset (liability) was comprised of the following as of December 31: Assets (Liabilities) 2017 2016 Deferred tax assets: Net operating loss carryforwards and credits $ 345,245 $ 454,749 Accrued compensation 11,514 17,036 Accrued legal settlements 6,596 25,442 Aircraft leases 17,323 16,109 Goodwill and other intangibles 7,267 15,798 Interest rate derivatives 1,532 3,124 Long-term debt 1,923 3,409 Obsolescence reserve 5,734 7,804 Stock-based compensation 3,296 6,731 Other 977 685 Total deferred tax assets 401,407 550,887 Valuation allowance (30,869 ) (49,396 ) Net deferred tax assets $ 370,538 $ 501,491 Deferred tax liabilities: Fixed assets $ (562,210 ) $ (778,905 ) Accrued expenses - (10 ) Acquisition of EETC debt (1,247 ) (4,079 ) Incentive related to Amazon (6,709 ) (6,829 ) Deferred maintenance (14,151 ) (8,614 ) Total deferred tax liabilities $ (584,317 ) $ (798,437 ) Deferred taxes included within following balance sheet line items: Deferred taxes $ (214,694 ) $ (298,165 ) Deferred costs and other assets 915 1,219 Net deferred tax assets (liabilities) $ (213,779 ) $ (296,946 )
Unrecognized Income Tax Benefits	A reconciliation of the beginning and ending unrecognized income tax benefits is as follows: 2017 2016 2015 Beginning balance $ 113,892 $ 112,555 $ 109,993 Additions for tax positions related to the current year 1,366 1,587 551 Additions for tax positions related to prior years 40 - 5,503 Reductions for tax positions related to prior years (43,581 ) (250 ) (3,492 ) Ending balance $ 71,717 $ 113,892 $ 112,555

Financial Instruments (Tables)

Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Summary of Carrying Value, Estimated Fair Value and Classification of Financial Instruments	The following table summarizes the carrying value, estimated fair value and classification of our financial instruments as of: December 31, 2017 Carrying Value Fair Value Level 1 Level 2 Level 3 Assets Cash and cash equivalents $ 280,809 $ 280,809 $ 280,809 $ - $ - Short-term investments 13,604 13,604 - - 13,604 Restricted cash 11,055 11,055 11,055 - - Long-term investments and accrued interest 15,371 18,074 - - 18,074 $ 320,839 $ 323,542 $ 291,864 $ - $ 31,678 Liabilities Term loans and notes $ 1,791,918 $ 1,844,445 $ - $ - $ 1,844,445 Convertible notes (1) 403,544 602,846 602,846 - - Amazon Warrant 127,755 127,755 - 127,755 - $ 2,323,217 $ 2,575,046 $ 602,846 $ 127,755 $ 1,844,445 December 31, 2016 Carrying Value Fair Value Level 1 Level 2 Level 3 Assets Cash and cash equivalents $ 123,890 $ 123,890 $ 123,890 $ - $ - Short-term investments 4,313 4,313 - - 4,313 Restricted cash 14,360 14,360 14,360 - - Long-term investments and accrued interest 27,951 33,161 - - 33,161 $ 170,514 $ 175,724 $ 138,250 $ - $ 37,474 Liabilities Term loans and notes $ 1,674,013 $ 1,739,744 $ - $ - $ 1,739,744 Convertible notes (1) 177,398 228,429 228,429 - - Amazon Warrant 95,775 95,775 - 95,775 - $ 1,947,186 $ 2,063,948 $ 228,429 $ 95,775 $ 1,739,744 (1) Carrying value is net of debt discounts and debt issuance costs. Hedge transactions associated with the Convertible Notes are reflected in additional paid-in-capital (see Note 9).

Segment Reporting (Tables)

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting Tables [Abstract]
Operating Revenue and Direct Contribution For Our Reportable Business Segments	The following table sets forth Operating Revenue and Direct Contribution for our reportable segments reconciled to Operating Income and Income (loss) from continuing operations before income taxes: For the Years Ended December 31, 2017 2016 2015 Operating Revenue: ACMI $ 988,741 $ 834,997 $ 791,442 Charter 1,034,562 881,991 908,753 Dry Leasing 119,820 105,795 107,218 Customer incentive asset amortization (5,261 ) (537 ) - Other 18,598 17,381 15,246 Total Operating Revenue $ 2,156,460 $ 1,839,627 $ 1,822,659 Direct Contribution: ACMI $ 231,271 $ 200,563 $ 185,615 Charter 151,388 133,727 124,808 Dry Leasing 39,939 33,114 42,023 Total Direct Contribution for Reportable Segments 422,598 367,404 352,446 Unallocated income and expenses, net (261,942 ) (242,768 ) (294,451 ) Loss on early extinguishment of debt (167 ) (132 ) (69,728 ) Unrealized loss on financial instruments (12,533 ) (2,888 ) - Gain on investments - - 13,439 Special charge (106 ) (10,140 ) (17,388 ) Transaction-related expenses (4,509 ) (22,071 ) - Gain (loss) on disposal of aircraft 31 11 (1,538 ) Income (loss) from continuing operations before income taxes 143,372 89,416 (17,220 ) Add back (subtract): Interest income (6,009 ) (5,532 ) (12,554 ) Interest expense 99,687 84,650 96,756 Capitalized interest (7,389 ) (3,313 ) (1,027 ) Loss on early extinguishment of debt 167 132 69,728 Unrealized loss on financial instruments 12,533 2,888 - Gain on investments - - (13,439 ) Other (income) expense (387 ) 70 1,261 Operating Income $ 241,974 $ 168,311 $ 123,505
Depreciation and Amortization by Reportable Business Segments	2017 2016 2015 Depreciation and amortization expense: ACMI $ 71,097 $ 61,630 $ 62,253 Charter 36,539 37,239 27,294 Dry Leasing 47,426 40,164 31,326 Unallocated 11,651 9,843 7,867 Total Depreciation and Amortization $ 166,713 $ 148,876 $ 128,740

Stock-Based and Long-term Inc42

Stock-Based and Long-term Incentive Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2017
Stock Based Compensation Plans Tables [Abstract]
Summary of Our Options	A summary of our options as of December 31, 2017 and changes during the year then ended is presented below: Number of Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Outstanding as of December 31, 2016 4,500 $ 58.89 Granted — — Exercised — — Forfeited, net of adjustments (4,500 ) 58.89 Outstanding as of December 31, 2017 — — — — Exercisable as of December 31, 2017 — — — —
Summary of Our Restricted Shares	A summary of our restricted shares as of December 31, 2017 and changes during the year then ended are presented below: Weighted- Average Restricted Share Awards Number of Shares Grant-Date Fair Value Unvested as of December 31, 2016 730,146 $ 39.89 Granted 327,303 54.40 Vested (266,896 ) 38.29 Forfeited (18,396 ) 54.74 Unvested as of December 31, 2017 772,157 $ 44.95
Summary of Our Performance Shares	A summary of our performance shares as of December 31, 2017 and changes during the year then ended are presented below: Weighted- Average Performance Share Awards Number of Shares Grant-Date Fair Value Unvested as of December 31, 2016 576,166 $ 27.30 Granted 97,205 54.20 Vested (201,324 ) 32.07 Forfeited (17,971 ) 43.03 Unvested as of December 31, 2017 454,076 $ 43.63

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Calculations of Basic and Diluted EPS	The calculations of basic and diluted EPS were as follows: For the Years Ended December 31, Numerator: 2017 2016 2015 Income from continuing operations, net of taxes $ 224,338 $ 42,625 $ 7,286 Denominator: Basic EPS weighted average shares outstanding 25,241 24,843 24,833 Effect of dilutive convertible notes 27 - - Effect of dilutive stock options and restricted stock 586 277 185 Diluted EPS weighted average shares outstanding 25,854 25,120 25,018 Earnings per share from continuing operations: Basic $ 8.89 $ 1.72 $ 0.29 Diluted $ 8.68 $ 1.70 $ 0.29 Loss per share from discontinued operations: Basic $ (0.03 ) $ (0.04 ) $ - Diluted $ (0.03 ) $ (0.04 ) $ - Earnings per share: Basic $ 8.85 $ 1.67 $ 0.29 Diluted $ 8.64 $ 1.65 $ 0.29

Accumulated Other Comprehensi44

Accumulated Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2017
Accumulated Other Comprehensive Income Loss [Abstract]
Components of Accumulated Other Comprehensive Income (Loss)	The following table summarizes t he components of Accumulated other comprehensive income (loss): Interest Rate Foreign Currency Derivatives Translation Total Balance as of December 31, 2015 $ (6,072 ) $ 9 $ (6,063 ) Reclassification to interest expense 1,770 - 1,770 Tax effect (700 ) - (700 ) Balance as of December 31, 2016 (5,002 ) 9 (4,993 ) Reclassification to interest expense 1,621 - 1,621 Tax effect (621 ) - (621 ) Balance as of December 31, 2017 $ (4,002 ) $ 9 $ (3,993 )

Selected Quarterly Financial 45

Selected Quarterly Financial Information (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure Abstract
Summary of Quarterly Financial Information	The following tables summarize the 2017 and 2016 quarterly results: First Second Third Fourth 2017* Quarter Quarter Quarter Quarter Total Operating Revenue $ 475,394 $ 517,366 $ 535,748 $ 627,952 Operating Income 24,036 58,478 52,712 106,748 Income (Loss) from continuing operations, net of taxes 35 39,044 (24,195 ) 209,454 Income (Loss) from discontinued operations, net of taxes (787 ) (105 ) 33 (6 ) Net Income (Loss) $ (752 ) $ 38,939 $ (24,162 ) $ 209,448 Earnings (Loss) per share from continuing operations: Basic $ 0.00 $ 1.55 $ (0.96 ) $ 8.28 Diluted** $ 0.00 $ 0.92 $ (0.96 ) $ 6.71 Loss per share from discontinued operations: Basic $ (0.03 ) $ (0.00 ) $ 0.00 $ (0.00 ) Diluted $ (0.03 ) $ (0.00 ) $ 0.00 $ (0.00 ) Earnings (Loss) per share: Basic $ (0.03 ) $ 1.54 $ (0.96 ) $ 8.28 Diluted** $ (0.03 ) $ 0.92 $ (0.96 ) $ 6.71 First Second Third Fourth 2016*** Quarter Quarter Quarter Quarter Total Operating Revenue $ 418,615 $ 443,272 $ 448,015 $ 529,725 Operating Income 20,057 20,824 25,998 101,432 Income (Loss) from continuing operations, net of taxes 471 20,919 (7,501 ) 28,736 Loss from discontinued operations, net of taxes - (345 ) (445 ) (319 ) Net Income (Loss) $ 471 $ 20,574 $ (7,946 ) $ 28,417 Earnings (Loss) per share from continuing operations: Basic $ 0.02 $ 0.84 $ (0.30 ) $ 1.15 Diluted**** $ 0.02 $ (0.26 ) $ (0.30 ) $ 1.12 Loss per share from discontinued operations: Basic $ - $ (0.01 ) $ (0.02 ) $ (0.01 ) Diluted $ - $ (0.01 ) $ (0.02 ) $ (0.01 ) Earnings (Loss) per share: Basic $ 0.02 $ 0.83 $ (0.32 ) $ 1.14 Diluted**** $ 0.02 $ (0.28 ) $ (0.32 ) $ 1.11 * Included in the first, second and third quarters were an unrealized loss on financial instruments of $5.2 million, an unrealized gain on financial instruments of $13.8 million and an unrealized loss on financial instruments of $44.8 million, respectively. Included in the fourth quarter was an income tax benefit of $130.0 million related to the U.S. Tax Cuts and Jobs Act (see Note 11) and an unrealized gain on financial instruments of $23.7 million. ** In 2017, the sum of quarterly diluted EPS amounts differs from the full year diluted EPS. The difference primarily relates to the exclusion from the calculation of diluted EPS of unrealized gains on financial instruments in the second and fourth quarters, and anti-dilutive shares in the third quarter, both related to the Amazon Warrant *** Included in the first quarter was **** In 2016, the sum of quarterly diluted EPS amounts differs from the full year diluted EPS. The difference primarily relates to the exclusion from the calculation of diluted EPS of an unrealized gain on financial instruments in the second quarter and anti-dilutive shares in the third quarter, both related to the Amazon Warrant.

Basis of Presentation - Additio

Basis of Presentation - Additional Information (Details)	Apr. 07, 2016	Dec. 31, 2017
Southern Air and Subsidiaries [Member]
Basis Of Presentation [Line Items]
Acquisition completion date	Apr. 7, 2016
Polar [Member]
Basis Of Presentation [Line Items]
Equity interest		51.00%
Voting interest		75.00%

Summary of Significant Account

Summary of Significant Account Policies - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Escrow Deposits And Letters Of Credit Details [Abstract]
Escrow deposits and letters of credit	$ 5.1	$ 5
Expendable Parts Inventory Details [Abstract]
Expendable parts net book value	34.7	24.2
Allowance for expendable obsolescence	27.8	22.3
Property and Equipment [Abstract]
Depreciation expense	153.1	141.5	$ 122.2
Net book value on flight equipment dry leased to customers	1,270.7	936
Accumulated depreciation on flight equipment on dry lease	152.7	99.8
Rotable parts inventory, net book value	184.8	142.7
Goodwill [Abstract]
Goodwill total balance	40.4	40.4
Prepaid Maintenance Deposits Details [Abstract]
Prepaid maintenance deposits	37.3	53.4
Recent Accounting Pronouncements [Abstract]
Amount of excess tax benefits recognition	$ 1.9
GATS [Member]
Variable Interest Entities And Off Balance Sheet Arrangements Details [Abstract]
Voting interest	50.00%
Investment in joint venture	$ 22.1	22.2
GATS [Member]
Variable Interest Entities And Off Balance Sheet Arrangements Details [Abstract]
Payables to related party	$ 0.4	$ 2.4

Summary of Significant Accoun48

Summary of Significant Account Policies - Property and Equipment Depreciable Lives (Details)	12 Months Ended
	Dec. 31, 2017
Minimum [Member] | Flight equipment [Member]
Property Plant And Equipment [Line Items]
Property and Equipment, depreciable life	30 years
Minimum [Member] | Computer software and equipment [Member]
Property Plant And Equipment [Line Items]
Property and Equipment, depreciable life	3 years
Minimum [Member] | Ground handling equipment and other [Member]
Property Plant And Equipment [Line Items]
Property and Equipment, depreciable life	3 years
Maximum [Member] | Flight equipment [Member]
Property Plant And Equipment [Line Items]
Property and Equipment, depreciable life	40 years
Maximum [Member] | Computer software and equipment [Member]
Property Plant And Equipment [Line Items]
Property and Equipment, depreciable life	5 years
Maximum [Member] | Ground handling equipment and other [Member]
Property Plant And Equipment [Line Items]
Property and Equipment, depreciable life	5 years

Summary of Significant Accoun49

Summary of Significant Account Policies - Schedule of Deferred Maintenance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Heavy Maintenance {Abstract}
Beginning balance, net	$ 19,100
Deferred maintenance costs	50,675	$ 19,644
Amortization of deferred maintenance	(5,907)	(544)
Ending balance, net	$ 63,868	$ 19,100

Summary of Significant Accoun50

Summary of Significant Account Policies - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest paid [Abstract]
Interest paid	$ 73,872	$ 66,306	$ 75,135
Income taxes paid [Abstract]
Income taxes paid, net of refunds	$ 563	$ 1,160	$ (228)

Summary of Significant Accoun51

Summary of Significant Account Policies - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounting Policies [Abstract]
Cash and cash equivalents	$ 280,809	$ 123,890
Restricted cash	11,055	14,360
Total Cash, cash equivalents and restricted cash shown in consolidated statements of cash flows	$ 291,864	$ 138,250	$ 438,931	$ 312,882

DHL Investment and Polar - Addi

DHL Investment and Polar - Additional Information (Details) - DHL [Member] - Polar [Member]	12 Months Ended
	Dec. 31, 2017
Related Party Transaction [Line Items]
Equity interest	49.00%
Voting interest	25.00%

DHL Investment and Polar - Summ

DHL Investment and Polar - Summary of Aircraft Types, Services and Number of Aircraft Provided to DHL (Details)	12 Months Ended
	Dec. 31, 2017
Service [Member]
Aircraft type [Line Items]
747-8F	ACMI
747-400F	ACMI
777-200LRF	CMI
767-300	CMI and Dry Leasing
767-200	CMI
737-400F	CMI
757-200F	Dry Leasing
Total Aircraft [Member]
Aircraft type [Line Items]
747-8F	6
747-400F	8
777-200LRF	5
767-300	4
767-200	9
737-400F	5
757-200F	1
Total	38

DHL Investment and Polar - Su54

DHL Investment and Polar - Summary of Transactions with Polar (Details) - Polar [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Related Party Transaction [Line Items]
Revenue from related party	$ 420,564	$ 407,891	$ 399,113
Ground handling and airport fees to Polar	2,746	1,667	$ 2,019
Receivables from related party	9,558	8,161
Payables to related party	2,751	2,019
Aggregate Carrying Value of Polar Investment	$ 4,870	$ 4,870

Southern Air Acquisition - Addi

Southern Air Acquisition - Additional Information (Details) - USD ($)	Apr. 07, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Total consideration transferred	$ 105,764,000
Operating Revenue		$ 2,156,460,000	$ 1,839,627,000	$ 1,822,659,000
Transaction-related expenses		4,509,000	22,071,000	0
Southern Air and Subsidiaries [Member]
Business Acquisition [Line Items]
Acquisition completion date	Apr. 7, 2016
Total consideration transferred	$ 105,800,000
Amortization expense on intangible assets		2,000	1,600
Operating Revenue			79,800,000
Transaction-related expenses		$ 4,500,000	17,700,000
Unaudited pro forma operating revenue			$ 1,866,700,000	$ 1,912,400,000

Southern Air Acquisition - Sche

Southern Air Acquisition - Schedule of Business Acquisition Consideration (Details) $ in Thousands	Apr. 07, 2016USD ($)
Business Combination Consideration Transferred [Abstract]
Cash paid, net of cash acquired	$ 107,498
Working capital adjustment	(2,106)
Other adjustments	372
Total consideration	$ 105,764

Southern Air Acquisition - Sc57

Southern Air Acquisition - Schedule of Business Acquisition Consideration (Parenthetical) (Details) $ in Thousands	Apr. 07, 2016USD ($)
Business Combination Consideration Transferred [Abstract]
Cash acquired from acquisition	$ 15,615

Southern Air Acquisition - Sc58

Southern Air Acquisition - Schedule of Amounts Recognized for Fair Values of Assets Acquired and Liabilities Assumed (Details) $ in Thousands	Apr. 07, 2016USD ($)
Business Combination Recognized Identifiable Assets Acquired Goodwill And Liabilities Assumed Less Noncontrolling Interest [Abstract]
Accounts receivable, net	$ 22,912
Prepaid expenses and other current assets	2,434
Property and equipment	6,355
Intangible assets and goodwill	67,341
Deferred income taxes, net	36,452
Other assets	1,498
Total assets acquired	136,992
Accounts payable and accrued liabilities	31,228
Total liabilities assumed	31,228
Net assets acquired	$ 105,764

Southern Air Acquisition - Sc59

Southern Air Acquisition - Schedule of Fair Values and Initial Useful Lives Assigned to Intangible Assets and Goodwill (Details) - USD ($) $ in Thousands	Apr. 07, 2016	Dec. 31, 2017	Dec. 31, 2016
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangible Assets Other Than Goodwill [Abstract]
Customer relationship	$ 26,280
Trade name	700	$ 700	$ 700
Goodwill	40,361	$ 40,361	$ 40,361
Total intangible assets and goodwill	$ 67,341
Customer relationship estimated useful life	16 years
Trade name estimated useful life	1 year 6 months

Southern Air Acquisition - Summ

Southern Air Acquisition - Summary of Employee Termination Benefit Liabilities (Details) - Employee Severance [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Restructuring Cost And Reserve [Line Items]
Beginning balance	$ 1,214	$ 3,797
Wind-down expenses	1,990
Cash payments	(3,133)	(2,583)
Ending balance	$ 71	$ 1,214

Special Charge - Additional Inf

Special Charge - Additional Information (Details) - CF6-80 Engines [Member] $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)Engine	Dec. 31, 2016USD ($)Engine	Dec. 31, 2015USD ($)Engine
Impairment Of Aircraft Engines Held For Sale [Line Items]
Number of assets held for sale | Engine		6	5
Number of assets traded | Engine	1	9
Impairment loss recognized for held for sale assets | $		$ 10.1	$ 8.3
Early termination of operating leases for engines | $			$ 7.7
Number of operating leases | Engine			2
Prepaid Expenses and Other Current Assets [Member]
Impairment Of Aircraft Engines Held For Sale [Line Items]
Carrying value of asset held for sale | $	$ 1.3	$ 2.8

Intangible Assets, Net and Go62

Intangible Assets, Net and Goodwill - Schedule of Intangible Assets, Net and Goodwill (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Apr. 07, 2016
Intangible Assets Table Details [Abstract]
Goodwill	$ 40,361	$ 40,361	$ 40,361
Fair value adjustments on operating leases	45,531	45,531
Lease intangible	54,891	57,203
Customer relationship	26,280	26,280
Trade name	700	700	$ 700
Less: accumulated amortization	(61,278)	(54,046)
Intangible assets, net	$ 106,485	$ 116,029

Intangible Assets, Net and Go63

Intangible Assets, Net and Goodwill - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Intangible Assets Amortization Expense Details [Abstract]
Amortization of Intangible Assets	$ 9.5	$ 9.8	$ 8.9

Intangible Assets, Net and Go64

Intangible Assets, Net and Goodwill - Schedule of Estimated Future Amortization Expense of Intangible Assets (Details) $ in Thousands	Dec. 31, 2017USD ($)
Schedule Of Estimated Amortization Expense Table Details [Abstract]
2,018	$ 8,792
2,019	8,094
2,020	8,047
2,021	8,547
2,022	8,862
Thereafter	23,782
Total	$ 66,124

Amazon - Additional Information

Amazon - Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Sep. 20, 2016
Class Of Warrant Or Right [Line Items]
Right to acquire outstanding common shares		up to 20% of our outstanding common shares
Warrant exercise price		$ 37.50
Warrant for number of shares vested immediately		3,750,000
Warrant to buy number of shares vesting	750,000	3,750,000
Vesting increments of Amazon warrants		375,000
Warrant vesting year		2,021
Warrants exercised		0
Additional warrant to acquire outstanding shares		up to an additional 10% of our outstanding common shares
Additional warrant exercise price		$ 37.50
Additional warrant to buy number of shares vesting		3,750,000
Portion of warrant vested	0	0
Additional warrant vesting year		2,023
Shareholder approval threshold				99.90%
Warrant maximum issuance of stocks				30.00%
Accelerated compensation expense			$ 23,500
Share-based portion of compensation expense			13,300
Warrant liability unrealized loss (gain)		$ 12,500,000	2,900,000
Fair value of warrant liability	$ 127,800,000	$ 127,800,000	$ 95,800,000
Maximum [Member]
Class Of Warrant Or Right [Line Items]
Warrant providing right to acquire outstanding common shares percentage		20.00%
Percentage of additional warrant to acquire outstanding common shares		10.00%
Dry Leases [Member]
Class Of Warrant Or Right [Line Items]
Lease term		10 years
CMI Operation [Member]
Class Of Warrant Or Right [Line Items]
Lease term		7 years

Amazon - Summary of the Custome

Amazon - Summary of the Customer Incentive Asset (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Warrants And Rights Note Disclosure [Abstract]
Beginning balance	$ 92,351
Initial value for vested portion of warrant	19,448	$ 92,888
Amortization of customer incentive asset	(5,261)	(537)
Ending balance	$ 106,538	$ 92,351

Accrued Liabilities - Schedule

Accrued Liabilities - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Accrued Liabilities Current And Noncurrent [Abstract]
Maintenance	$ 156,042	$ 54,495
Customer maintenance reserves	89,037	81,830
Salaries, wages and benefits	65,546	55,063
U.S. class action settlement	30,000	35,000
Aircraft fuel	22,196	16,149
Deferred revenue	20,986	10,298
Other	71,036	68,052
Accrued liabilities	$ 454,843	$ 320,887

Debt - Debt Obligations (Detail

Debt - Debt Obligations (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total principal amount of debt and capital leases		$ 2,378,819	$ 1,943,394
Less: unamortized debt discount and issuance costs		(151,820)	(91,983)
Total debt		2,226,999	1,851,411
Less current portion of debt and capital leases		(218,013)	(184,748)
Long-term debt and capital lease		2,008,986	1,666,663
Ex-Im Guaranteed Notes [Member]
Debt Instrument [Line Items]
Ex-Im Guaranteed Notes		$ 564,184	$ 645,537
Interest Rates	[1]	1.89%	1.89%
Ex-Im Guaranteed Notes [Member] | Minimum [Member]
Debt Instrument [Line Items]
Range of Maturity Dates		2,021
Ex-Im Guaranteed Notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Range of Maturity Dates		2,025
Term Loans and Capital Lease [Member]
Debt Instrument [Line Items]
Term loans and capital leases		$ 1,145,116	$ 1,053,273
Interest Rates	[1]	4.16%	4.34%
Term Loans and Capital Lease [Member] | Minimum [Member]
Debt Instrument [Line Items]
Range of Maturity Dates		2,020
Term Loans and Capital Lease [Member] | Maximum [Member]
Debt Instrument [Line Items]
Range of Maturity Dates		2,032
Private Placement Facility [Member]
Debt Instrument [Line Items]
Private Placement Facility		$ 144,539
Interest Rates	[1]	3.17%
Private Placement Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Range of Maturity Dates		2,025
Private Placement Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Range of Maturity Dates		2,026
Convertible Notes [Member]
Debt Instrument [Line Items]
Convertible Notes		$ 513,500	$ 224,500
Interest Rates	[1]	2.04%	2.25%
Convertible Notes [Member] | Minimum [Member]
Debt Instrument [Line Items]
Range of Maturity Dates		2,022
Convertible Notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Range of Maturity Dates		2,024
EETCs [Member]
Debt Instrument [Line Items]
EETC		$ 11,480	$ 20,084
Range of Maturity Dates		2,019
Interest Rates	[1]	7.52%	7.52%
[1]	Interest rates reflect weighted-average rates as of year-end

Debt - Schedule of Term Loans (

Debt - Schedule of Term Loans (Details) - Term Loans and Capital Lease [Member]	12 Months Ended
	Dec. 31, 2017USD ($)
Debt Instrument [Line Items]
Face Value	$ 185,700,000
First 2017 Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-04
Face Value	$ 20,100,000
Collateral Type	767-300
Original Term	91 months
Fixed Interest Rate	3.02%
Second 2017 Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-04
Face Value	$ 21,300,000
Collateral Type	767-300
Original Term	91 months
Fixed Interest Rate	3.16%
Third 2017 Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-05
Face Value	$ 21,500,000
Collateral Type	767-300
Original Term	91 months
Fixed Interest Rate	3.16%
Fourth 2017 Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-06
Face Value	$ 21,300,000
Collateral Type	767-300
Original Term	91 months
Fixed Interest Rate	3.09%
Fifth 2017 Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-06
Face Value	$ 21,700,000
Collateral Type	767-300
Original Term	91 months
Fixed Interest Rate	3.11%
Sixth 2017 Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-06
Face Value	$ 21,700,000
Collateral Type	767-300
Original Term	91 months
Fixed Interest Rate	3.11%
Seventh 2017 Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-06
Face Value	$ 18,700,000
Collateral Type	None
Original Term	58 months
Fixed Interest Rate	2.17%
Eighth 2017 Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-07
Face Value	$ 12,500,000
Collateral Type	767-300
Original Term	60 months
Fixed Interest Rate	3.62%
Ninth 2017 Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-11
Face Value	$ 26,900,000
Collateral Type	None
Original Term	60 months
Fixed Interest Rate	2.38%

Debt - Term Loans and Capital L

Debt - Term Loans and Capital Leases - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2017
Debt Instrument [Line Items]
Lease extended expiration date	2032-06
Capital lease obligation	$ 32.4
Capital Lease Amended [Member]
Debt Instrument [Line Items]
Issue date	2017-03
Collateral Type		747-400 freighter

Debt - Private Placement Facili

Debt - Private Placement Facility - Additional Information (Details) - Private Placement Facility [Member]	1 Months Ended
	Sep. 30, 2017USD ($)FreighterAircraft
Debt Instrument [Line Items]
Debt facility amount | $	$ 145,800,000
Number of freighter aircraft dry leased | FreighterAircraft	6

Debt - Schedule of Financing un

Debt - Schedule of Financing under Private Placement Facility (Details) - Private Placement Facility [Member]	12 Months Ended
	Dec. 31, 2017USD ($)
Debt Instrument [Line Items]
Face Value	$ 145,800,000
First 2017 Equipment Note [Member]
Debt Instrument [Line Items]
Issue Date	2017-10
Face Value	$ 21,200,000
Collateral Type	Dry Lease and 767-300
Original Term	87 months
Fixed Interest Rate	2.93%
First 2017 Equipment Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-10
Face Value	$ 2,600,000
Collateral Type	Dry Lease and 767-300
Original Term	103 months
Fixed Interest Rate	4.75%
Second 2017 Equipment Note [Member]
Debt Instrument [Line Items]
Issue Date	2017-10
Face Value	$ 21,400,000
Collateral Type	Dry Lease and 767-300
Original Term	88 months
Fixed Interest Rate	2.93%
Second 2017 Equipment Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-10
Face Value	$ 3,200,000
Collateral Type	Dry Lease and 767-300
Original Term	107 months
Fixed Interest Rate	4.75%
Third 2017 Equipment Note [Member]
Debt Instrument [Line Items]
Issue Date	2017-10
Face Value	$ 21,200,000
Collateral Type	Dry Lease and 767-300
Original Term	87 months
Fixed Interest Rate	2.93%
Third 2017 Equipment Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-10
Face Value	$ 3,000,000
Collateral Type	Dry Lease and 767-300
Original Term	105 months
Fixed Interest Rate	4.75%
Fourth 2017 Equipment Note [Member]
Debt Instrument [Line Items]
Issue Date	2017-12
Face Value	$ 21,200,000
Collateral Type	Dry Lease and 767-300
Original Term	88 months
Fixed Interest Rate	2.93%
Fourth 2017 Equipment Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-12
Face Value	$ 2,900,000
Collateral Type	Dry Lease and 767-300
Original Term	104 months
Fixed Interest Rate	4.87%
Fifth 2017 Equipment Note [Member]
Debt Instrument [Line Items]
Issue Date	2017-12
Face Value	$ 21,400,000
Collateral Type	Dry Lease and 767-300
Original Term	89 months
Fixed Interest Rate	2.93%
Fifth 2017 Equipment Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-12
Face Value	$ 3,200,000
Collateral Type	Dry Lease and 767-300
Original Term	107 months
Fixed Interest Rate	4.87%
Sixth 2017 Equipment Note [Member]
Debt Instrument [Line Items]
Issue Date	2017-12
Face Value	$ 21,400,000
Collateral Type	Dry Lease and 767-300
Original Term	88 months
Fixed Interest Rate	2.93%
Sixth 2017 Equipment Term Loan [Member]
Debt Instrument [Line Items]
Issue Date	2017-12
Face Value	$ 3,100,000
Collateral Type	Dry Lease and 767-300
Original Term	106 months
Fixed Interest Rate	4.94%

Debt - Convertible Notes - Addi

Debt - Convertible Notes - Additional Information (Details) $ / shares in Units, $ in Thousands	1 Months Ended		12 Months Ended
	May 31, 2017USD ($)	Jun. 30, 2015USD ($)	Dec. 31, 2017USD ($)Day$ / shares	Dec. 31, 2015USD ($)	Dec. 31, 2016USD ($)
Debt Instrument [Line Items]
Refinanced enhanced equipment trust certificates (EETCs)				$ 187,800
Aggregate amount of EETCs refinanced interest rate				8.10%
Loss on early extinquishment for EETC				$ 66,700
Debt extinguishment costs paid to the EETC equipment note holders				34,000
Debt extinguishment write-off of the debt discount				32,700
Gain on investments from EETCs				$ 13,400
Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, repurchase percentage			100.00%
Debt instrument, convertible, threshold trading days | Day			20
Debt instrument, convertible, threshold consecutive trading days | Day			30
Debt instrument, convertible, threshold percentage of stock price trigger			130.00%
Debt instrument, convertible, threshold business days			5 days
Debt instrument, convertible, threshold consecutive measurement period			5 days
Debt instrument, convertible, threshold percentage of stock price trigger in measurement period			98.00%
2017 Convertible Notes [Member]
Debt Instrument [Line Items]
Convertible notes aggregate principal amount	$ 289,000		$ 289,000
Debt instrument, maturity date	Jun. 1, 2024
Debt instrument, conversion price | $ / shares			$ 61.08
Effective interest rate of debt			6.14%
Debt issuance costs			$ 7,500
Liability issuance costs			5,700
Equity issuance costs			$ 1,800
2017 Convertible Notes [Member] | Warrant [Member]
Debt Instrument [Line Items]
Debt instrument, conversion price | $ / shares			$ 92.20
2017 Convertible Notes [Member] | Long-term Debt and Capital Lease [Member] | Revolver [Member]
Debt Instrument [Line Items]
Repayment line of credit outstanding balance	$ 150,000
2015 Convertible Notes [Member]
Debt Instrument [Line Items]
Convertible notes aggregate principal amount		$ 224,500	$ 224,500		$ 224,500
Debt instrument, maturity date		Jun. 1, 2022
Debt instrument, conversion price | $ / shares			$ 74.05
Effective interest rate of debt			6.44%
Debt issuance costs			$ 6,800
Liability issuance costs			5,200
Equity issuance costs			$ 1,600
2015 Convertible Notes [Member] | Warrant [Member]
Debt Instrument [Line Items]
Debt instrument, conversion price | $ / shares			$ 95.01

Debt - Certain Key Terms for Co

Debt - Certain Key Terms for Convertible Note (Details)	12 Months Ended
	Dec. 31, 2017$ / shares
2017 Convertible Notes [Member]
Debt Instrument [Line Items]
Fixed Interest Rate	1.88%
Earliest conversion date	Sep. 1, 2023
Initial conversion price per share	$ 61.08
Conversion rate (shares for each $1,000 of principal)	16.3713
2015 Convertible Notes [Member]
Debt Instrument [Line Items]
Fixed Interest Rate	2.25%
Earliest conversion date	Sep. 1, 2021
Initial conversion price per share	$ 74.05
Conversion rate (shares for each $1,000 of principal)	13.5036

Debt - Summary of Convertible N

Debt - Summary of Convertible Note Hedges and Related Warrants (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Proceeds from sale of convertible note warrants		$ 38,148	$ 0	$ 36,290
2017 Convertible Notes [Member]
Debt Instrument [Line Items]
Number of shares	[1]	4,731,306
Initial price per share		$ 61.08
Cost of hedge		$ 70,140
2017 Convertible Notes [Member] | Warrant [Member]
Debt Instrument [Line Items]
Number of shares	[1]	4,731,306
Initial price per share		$ 92.20
Proceeds from sale of convertible note warrants		$ 38,148
2015 Convertible Notes [Member]
Debt Instrument [Line Items]
Number of shares	[1]	3,031,558
Initial price per share		$ 74.05
Cost of hedge		$ 52,903
2015 Convertible Notes [Member] | Warrant [Member]
Debt Instrument [Line Items]
Number of shares	[1]	3,031,558
Initial price per share		$ 95.01
Proceeds from sale of convertible note warrants		$ 36,290
[1]	Subject to adjustment for certain specified events

Debt - Schedule of Convertible

Debt - Schedule of Convertible Notes (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	May 31, 2017	Jun. 30, 2015
Debt Instrument [Line Items]
Less: debt discount, net of amortization		$ (151,820)
2017 Convertible Notes [Member]
Debt Instrument [Line Items]
Remaining life in months		77 months
Gross proceeds		$ 289,000		$ 289,000
Less: debt discount, net of amortization		(65,187)
Less: debt issuance cost, net of amortization		(5,216)
Net carrying amount		218,597
Equity component	[1]	$ 70,140
2015 Convertible Notes [Member]
Debt Instrument [Line Items]
Remaining life in months		53 months	65 months
Gross proceeds		$ 224,500	$ 224,500		$ 224,500
Less: debt discount, net of amortization		(36,108)	(42,956)
Less: debt issuance cost, net of amortization		(3,445)	(4,146)
Net carrying amount		184,947	177,398
Equity component	[1]	$ 52,903	$ 52,903
[1]	Included in Additional paid-in capital on the consolidated balance sheets.

Debt - Summary of Interest Expe

Debt - Summary of Interest Expense Recognized (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Short Term Debt [Line Items]
Total interest expense recognized	$ 99,687	$ 84,650	$ 96,756
Convertible Notes [Member]
Short Term Debt [Line Items]
Contractual interest coupon	8,348	5,051
Amortization of debt discount	11,801	6,421
Amortization of debt issuance costs	1,132	677
Total interest expense recognized	$ 21,281	$ 12,149

Debt - EETC - Additional Inform

Debt - EETC - Additional Information (Details) - EETC [Member] $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)
Debt Instrument [Line Items]
Issue Date	1,999
Face Value	$ 109.9
Debt instrument maturity date	2019-02
Collateral Type	747-400F
Effective interest rate of debt	7.52%
Minimum [Member]
Debt Instrument [Line Items]
Fixed Interest Rate	6.88%
Maximum [Member]
Debt Instrument [Line Items]
Fixed Interest Rate	8.77%

Debt - Revolving Credit Facilit

Debt - Revolving Credit Facility - Additional Information (Details) - Revolver [Member] - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Term of revolving credit facility		3 years
Borrowing capacity		$ 150,000,000
Revolver collateral	nine 747-400 and five 767-300 aircraft
Revolver interest rate description	LIBOR plus a margin of 2.25% per annum
Debt Instrument, Basis spread on variable Interest rate		2.25%
Interest rate of undrawn portion		0.40%
Outstanding balance	$ 0	$ 0
Unused availability	$ 139,300,000

Debt - Schedule of Future Cash

Debt - Schedule of Future Cash Payments for Debt (Details) $ in Thousands	Dec. 31, 2017USD ($)
Long Term Debt By Maturity [Abstract]
2,018	$ 230,464
2,019	230,537
2,020	343,624
2,021	238,223
2,022	426,789
Thereafter	909,182
Total debt cash payments	2,378,819
Less: unamortized debt discount and issuance costs	(151,820)
Debt	$ 2,226,999

Commitments - Additional Inform

Commitments - Additional Information (Details)	12 Months Ended
	Dec. 31, 2017IssuanceSeriesNumber
Operating Leased Assets [Line Items]
Number of series equipment notes are issued	3
Operating lease average remaining lease term	5 years 1 month 6 days
Description of lease agreement	As of December 31, 2017, 15 of our 73 aircraft were under operating leases, with lease term expiration dates ranging from 2020 to 2025 and an average remaining lease term of 5.1 years.
Minimum [Member]
Operating Leased Assets [Line Items]
Operating lease expiration year	2,020
Maximum [Member]
Operating Leased Assets [Line Items]
Operating lease expiration year	2,025
Original owner participant [Member]
Operating Leased Assets [Line Items]
Percentage of each aircraft cost invested on an equity basis	20.00%
Wells Fargo [Member]
Operating Leased Assets [Line Items]
Percentage of each aircraft cost financed with nonrecourse debt	80.00%

Commitments - Summary of Rental

Commitments - Summary of Rental Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Commitments [Abstract]
Aircraft and engines	$ 142,945	$ 146,110	$ 145,031
Purchased capacity, office, vehicles and other	$ 46,817	$ 23,727	$ 44,228

Commitments - Summary of Minimu

Commitments - Summary of Minimum Annual Rental Commitments (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)
Aircraft Operating Leases [Member]
Minimum Annual Commitments [Line Items]
2,018	$ 138,223
2,019	154,461
2,020	149,214
2,021	157,985
2,022	111,064
Thereafter	109,993
Total minimum rental payments	820,940
Other Operating Leases [Member]
Minimum Annual Commitments [Line Items]
2,018	7,003
2,019	6,466
2,020	5,908
2,021	4,680
2,022	1,843
Thereafter	27
Total minimum rental payments	25,927
Total [Member]
Minimum Annual Commitments [Line Items]
2,018	145,226
2,019	160,927
2,020	155,122
2,021	162,665
2,022	112,907
Thereafter	110,020
Total minimum rental payments	$ 846,867

Commitments - Summary of Contra

Commitments - Summary of Contractual Amount of Minimum Dry Lease Income (Details) $ in Thousands	Dec. 31, 2017USD ($)
Operating Leased Assets [Line Items]
2,018	$ 192,463
2,019	127,597
2,020	117,222
2,021	98,668
2,022	95,424
Thereafter	219,033
Total minimum lease receipts	850,407
Dry Lease Income [Member]
Operating Leased Assets [Line Items]
2,018	139,663
2,019	127,597
2,020	117,222
2,021	98,668
2,022	95,424
Thereafter	219,033
Total minimum lease receipts	797,607
Sublease Income [Member]
Operating Leased Assets [Line Items]
2,018	52,800
2,019	0
2,020	0
2,021	0
2,022	0
Thereafter	0
Total minimum lease receipts	$ 52,800

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Line Items]
U.S. federal corporate income tax rate			35.00%	35.00%	35.00%
Provisional income tax benefits in connection with remeasurement of U.S. net deferred tax liability	$ 130		$ 130
U.S. NOLs	1,200		$ 1,200	$ 1,000
NOL Expirations			2,037
U.S. federal tax credits	4.5		$ 4.5	4.7
Credits refundable on income tax returns period description			Pursuant to the U.S. Tax Cuts and Jobs Act, these credits are refundable on our income tax returns from 2018 through 2021.
Foreign NOLs for HK and Singapore	465.3		$ 465.3	463.5
Aircraft leasing incentive program, reduced tax rate			10.00%
Aircraft leasing incentive program participation expire date			Jul. 31, 2018
Aircraft leasing incentive program, reduced tax rate upon renewal			8.00%
Aircraft leasing incentive program, tax rate if not renewed			17.00%
Valuation allowance	30.9		$ 30.9	49.4
Adjustment to the valuation allowance primarily due to change in federal income tax rate under U.S. Tax Cuts and Jobs Act			18.5	1.3
Tax-related interest benefit			0	0
Cumulative liability for tax-related interest	$ 0.1		$ 0.1	$ 0.1
Income tax examination description			For U.S. federal income tax purposes, the 2012 through 2017 income tax years remain subject to examination. The Company is currently undergoing a federal income tax examination for the tax year ending 2015 as well as income tax examinations in Illinois and New Jersey. The Company files income tax returns in multiple foreign jurisdictions, primarily in Singapore and Hong Kong. The 2012 through 2017 Singapore income tax years and 2010 through 2017 Hong Kong income tax years are subject to examination. The Company is currently undergoing income tax examinations in Hong Kong for the periods 2010 through 2016.
U.S. Federal [Member]
Income Taxes [Line Items]
Income tax examination tax year under examination			2,015
Foreign [Member] | Hong Kong [Member] | Tax Year 2010 [Member]
Income Taxes [Line Items]
Income tax examination tax year under examination			2,010
Foreign [Member] | Hong Kong [Member] | Tax Year 2016 [Member]
Income Taxes [Line Items]
Income tax examination tax year under examination			2,016
Scenario Forecast [Member]
Income Taxes [Line Items]
U.S. federal corporate income tax rate		21.00%

Income Taxes - Components of th

Income Taxes - Components of the Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Federal	$ (133)	$ (376)	$ 52
State and local	(99)	(298)	48
Foreign	596	84	1,292
Total current expense	364	(590)	1,392
Deferred:
Federal	(87,185)	46,391	(24,425)
State and local	1,868	(1,436)	(3,531)
Foreign	3,987	2,426	2,058
Total deferred expense (benefit)	(81,330)	47,381	(25,898)
Total income tax expense (benefit)	$ (80,966)	$ 46,791	$ (24,506)

Income Taxes - Domestic and For

Income Taxes - Domestic and Foreign Earnings before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Domestic and foreign earnings before income taxes
Domestic	$ 104,321	$ 61,006	$ (57,825)
Foreign	39,051	28,410	40,605
Income (loss) from continuing operations before income taxes	$ 143,372	$ 89,416	$ (17,220)

Income Taxes - Effective Income

Income Taxes - Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of differences between the U.S. federal statutory income tax rate and the effective income tax rates
U.S. federal statutory income tax rate	35.00%	35.00%	35.00%
State and local taxes based on income, net of federal benefit	0.30%	1.10%	2.00%
Change in deferred foreign and state tax rates	0.60%	(2.20%)	12.00%
Nondeductible customer incentive related to Amazon	5.00%	10.90%	0.00%
Nondeductible compensation expenses related to Amazon		13.00%	0.00%
Other nondeductible expenses	1.40%	4.30%	(10.20%)
Extraterritorial income tax benefit			23.30%
Tax incentives and additional deductions	(0.60%)	(0.90%)	4.90%
Favorable resolution of income tax issues			13.80%
Tax effect of foreign operations	(7.70%)	(9.40%)	66.40%
Impact of U.S. Tax Cuts and Jobs Act	(90.70%)
Other	0.20%	0.50%	(4.90%)
Effective income tax rate	(56.50%)	52.30%	142.30%

Income Taxes - Deferred Tax Ass

Income Taxes - Deferred Tax Assets (Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax assets:
Net operating loss carryforwards and credits	$ 345,245	$ 454,749
Accrued compensation	11,514	17,036
Accrued legal settlements	6,596	25,442
Aircraft leases	17,323	16,109
Goodwill and other intangibles	7,267	15,798
Interest rate derivatives	1,532	3,124
Long-term debt	1,923	3,409
Obsolescence reserve	5,734	7,804
Stock-based compensation	3,296	6,731
Other	977	685
Total deferred tax assets	401,407	550,887
Valuation allowance	(30,869)	(49,396)
Net deferred tax assets	370,538	501,491
Deferred tax liabilities:
Fixed assets	(562,210)	(778,905)
Accrued expenses		(10)
Acquisition of EETC debt	(1,247)	(4,079)
Incentive related to Amazon	(6,709)	(6,829)
Deferred maintenance	(14,151)	(8,614)
Total deferred tax liabilities	(584,317)	(798,437)
Deferred taxes included within following balance sheet line items:
Deferred taxes	(214,694)	(298,165)
Deferred costs and other assets	915	1,219
Net deferred tax assets (liabilities)	$ (213,779)	$ (296,946)

Income Taxes - Unrecognized Inc

Income Taxes - Unrecognized Income Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 113,892	$ 112,555	$ 109,993
Additions for tax positions related to the current year	1,366	1,587	551
Additions for tax positions related to prior years	40		5,503
Reductions for tax positions related to prior years	(43,581)	(250)	(3,492)
Ending balance	$ 71,717	$ 113,892	$ 112,555

Financial Instruments - Additio

Financial Instruments - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Long Term Investments Details [Abstract]
Long-term investments maturing period	5 years
Gross unrealized gains on long-term investments and accrued interest	$ 2,700	$ 5,200
Gain on investments	$ 0	$ 0	$ 13,439
Debt redemption premium			5,700
Gain from investment discount			$ 7,700

Financial Instruments - Summary

Financial Instruments - Summary of Carrying Value, Estimated Fair Value and Classification of Financial Instruments (Details) - USD ($) $ in Thousands		Dec. 31, 2017	Dec. 31, 2016
Assets
Short-term investments		$ 13,604	$ 4,313
Restricted cash		11,055	14,360
Long-term investments and accrued interest		15,371	27,951
Liabilities
Amazon Warrant		106,538	92,351
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Assets
Cash and cash equivalents		280,809	123,890
Short-term investments		13,604	4,313
Restricted cash		11,055	14,360
Long-term investments and accrued interest		15,371	27,951
Financial instruments assets		320,839	170,514
Liabilities
Term loans and notes		1,791,918	1,674,013
Convertible notes (1)	[1]	403,544	177,398
Amazon Warrant		127,755	95,775
Financial instruments liabilities		2,323,217	1,947,186
Estimate of Fair Value, Fair Value Disclosure [Member]
Assets
Cash and cash equivalents		280,809	123,890
Short-term investments		13,604	4,313
Restricted cash		11,055	14,360
Long-term investments and accrued interest		18,074	33,161
Financial instruments assets		323,542	175,724
Liabilities
Term loans and notes		1,844,445	1,739,744
Convertible notes (1)	[1]	602,846	228,429
Amazon Warrant		127,755	95,775
Financial instruments liabilities		2,575,046	2,063,948
Fair Value, Inputs, Level 1 [Member]
Assets
Cash and cash equivalents		280,809	123,890
Short-term investments		0	0
Restricted cash		11,055	14,360
Long-term investments and accrued interest		0	0
Financial instruments assets		291,864	138,250
Liabilities
Term loans and notes		0	0
Convertible notes (1)	[1]	602,846	228,429
Amazon Warrant		0	0
Financial instruments liabilities		602,846	228,429
Fair Value, Inputs, Level 2 [Member]
Assets
Cash and cash equivalents		0	0
Short-term investments		0	0
Restricted cash		0	0
Long-term investments and accrued interest		0	0
Financial instruments assets		0	0
Liabilities
Term loans and notes		0	0
Convertible notes (1)	[1]	0	0
Amazon Warrant		127,755	95,775
Financial instruments liabilities		127,755	95,775
Fair Value, Inputs, Level 3 [Member]
Assets
Cash and cash equivalents		0	0
Short-term investments		13,604	4,313
Restricted cash		0	0
Long-term investments and accrued interest		18,074	33,161
Financial instruments assets		31,678	37,474
Liabilities
Term loans and notes		1,844,445	1,739,744
Convertible notes (1)	[1]	0	0
Amazon Warrant		0	0
Financial instruments liabilities		$ 1,844,445	$ 1,739,744
[1]	Carrying value is net of debt discounts and debt issuance costs. Hedge transactions associated with the Convertible Notes are reflected in additional paid-in-capital (see Note 9).

Segment Reporting - Additional

Segment Reporting - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)Segment	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | Segment	3
Operating Revenue	$ 2,156,460	$ 1,839,627	$ 1,822,659
DHL [Member]
Segment Reporting Information [Line Items]
Operating Revenue	262,600	195,100	113,000
Charter [Member]
Segment Reporting Information [Line Items]
Operating Revenue	1,034,562	881,991	908,753
Charter [Member] | AMC Charter [Member]
Segment Reporting Information [Line Items]
Operating Revenue	$ 496,300	$ 436,100	$ 418,300

Segment Reporting - Operating R

Segment Reporting - Operating Revenue and Direct Contribution For Our Reportable Business Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Revenue:
Operating Revenue	$ 2,156,460	$ 1,839,627	$ 1,822,659
Customer incentive asset amortization	(5,261)	(537)	0
Other	18,598	17,381	15,246
Direct Contribution:
Total Direct Contribution for Reportable Segments	422,598	367,404	352,446
Unallocated income and expenses, net	(261,942)	(242,768)	(294,451)
Loss on early extinguishment of debt	(167)	(132)	(69,728)
Unrealized loss on financial instruments	(12,533)	(2,888)	0
Gain on investments	0	0	13,439
Special charge	(106)	(10,140)	(17,388)
Transaction-related expenses	(4,509)	(22,071)	0
Gain (loss) on disposal of aircraft	31	11	(1,538)
Income (loss) from continuing operations before income taxes	143,372	89,416	(17,220)
Interest income	(6,009)	(5,532)	(12,554)
Interest expense	99,687	84,650	96,756
Capitalized interest	(7,389)	(3,313)	(1,027)
Unrealized loss on financial instruments	12,533	2,888	0
Gain on investments	0	0	(13,439)
Other (income) expense	(387)	70	1,261
Operating Income	241,974	168,311	123,505
ACMI [Member]
Operating Revenue:
Operating Revenue	988,741	834,997	791,442
Direct Contribution:
Total Direct Contribution for Reportable Segments	231,271	200,563	185,615
Charter [Member]
Operating Revenue:
Operating Revenue	1,034,562	881,991	908,753
Direct Contribution:
Total Direct Contribution for Reportable Segments	151,388	133,727	124,808
Dry Leasing [Member]
Operating Revenue:
Operating Revenue	119,820	105,795	107,218
Direct Contribution:
Total Direct Contribution for Reportable Segments	$ 39,939	$ 33,114	$ 42,023

Segment Reporting - Depreciatio

Segment Reporting - Depreciation and Amortization by Reportable Business Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segmentreportingdepreciationandamortizationabstract
ACMI	$ 71,097	$ 61,630	$ 62,253
Charter	36,539	37,239	27,294
Dry Leasing	47,426	40,164	31,326
Unallocated	11,651	9,843	7,867
Total Depreciation and Amortization	$ 166,713	$ 148,876	$ 128,740

Labor and Legal Proceedings - A

Labor and Legal Proceedings - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Jan. 31, 2018	Dec. 31, 2016
Loss Contingencies [Line Items]
Total legal settlement accrued for the U. S. class action	$ 30
Matters Related To Alleged Pricing Practices | Subsequent Event [Member]
Loss Contingencies [Line Items]
Legal settlement last payment amount		$ 30
Brazilian Customs Claim [Member]
Loss Contingencies [Line Items]
Brazilian claims in the aggregate	9.2
Amounts on deposit for Brazilian claims included in deferred costs and other assets	$ 5.1		$ 5
Atlas Pilots [Member]
Loss Contingencies [Line Items]
Collective bargaining agreement period	5 years
Southern Air Pilots [Member]
Loss Contingencies [Line Items]
Collective bargaining agreement period	4 years
Atlas and Polar Dispatchers [Member]
Loss Contingencies [Line Items]
Collective bargaining agreement period	5 years

Stock-Based and Long-term Inc97

Stock-Based and Long-term Incentive Compensation Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for issuance under the 2007 LTIP	600,000
Number of shares authorized under the 2007 LTIP	2,800,000
2007 LTIP terms	In 2016, the stockholders approved a revised Long-Term Incentive Plan (the “2016 Plan”), which replaced the 2007 Plan.
2016 LTIP number of shares available for future award grants	800,000
Maximum term of award under the 2016 LTIP	P10Y
LTIP compensation expense	$ 20,900	$ 30,900	$ 15,000
Tax benefit recognized for stock-based compensation arrangements	$ 5,300	8,700	5,700
Shares of common stock available for future award grants under 2016 plan	500,000
Non-qualified stock options terms	Nonqualified stock options, which have not been granted since 2007, vest over a three- or four-year period and expire seven to ten years from the date of grant.
Proceeds from stock option exercises	$ 0	0	$ 1,193
Number of Options, Exercised	0		25,373
Restricted shares vesting period	Restricted shares granted vest and are expensed over one-, three- or four- year periods.
Restricted shares unrecognized compensation cost	$ 20,400
Restricted shares remaining weighted average life (in years)	2 years 1 month 6 days
Total fair value, on vesting date, of restricted shares vested	$ 14,800	19,800	$ 13,700
Performance shares vesting period	Performance share and performance cash awards granted are expensed over three years, which generally is the requisite service period. Awards generally become vested if (1) we achieve certain specified performance levels compared with predetermined performance thresholds during a three-year period starting in the grant year and ending on December 31 three years later, and (2) the employee remains employed by us through the determination date which can be no later than four months following the end of the Performance Period. Full or partial vesting may occur for certain employee terminations.
Total performance shares granted	1,800,000
Performance shares unrecognized compensation cost	$ 5,800
Performance shares remaining weighted average life (in years)	1 year 4 months 24 days
Accrued performance cash awards	$ 13,800	13,100
Performance cash awards expense	7,100	13,900	1,600
Total fair value, on vesting date, of performance shares vested	$ 10,600	$ 5,800	$ 3,700
Restricted Share Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted	327,303
Weighted average grant date fair value	$ 54.40	$ 36.10	$ 47.10
Performance Share Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted	97,205
Weighted average grant date fair value	$ 54.20	$ 37.21	$ 47.48
2007 and 2016 Plans [Member] | Restricted Share Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, granted	3,800,000

Stock-Based and Long-term Inc98

Stock-Based and Long-term Incentive Compensation Plans - Summary of Our Options (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2015
Share Based Compensation [Abstract]
Number of Options, Outstanding beginning balance	4,500
Number of Options, Granted	0
Number of Options, Exercised	0	25,373
Number of Options, Forfeited, net of adjustments	(4,500)
Number of Options, Outstanding ending balance	0
Number of Options, Exercisable as of December 31, 2017	0
Weighted-Average Exercise Price, Outstanding beginning balance	$ 58.89
Weighted-Average Exercise Price, Granted	0
Weighted-Average Exercise Price, Exercised	0
Weighted-Average Exercise Price, Forfeited, net of adjustments	58.89
Weighted-Average Exercise Price, Outstanding ending balance	0
Weighted-Average Exercise Price, Exercisable as of December 31, 2017	$ 0
Weighted-Average Remaining Contractual Term, Outstanding	0 years
Weighted-Average Remaining Contractual Term, Exercisable	0 years
Aggregate Intrinsic Value, Outstanding	$ 0
Aggregate Intrinsic Value, Exercisable	$ 0

Stock-Based and Long-term Inc99

Stock-Based and Long-term Incentive Compensation Plans - Summary of Our Restricted Shares (Details) - Restricted Share Awards [Member] - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Unvested beginning balance	730,146
Number of Shares, Granted	327,303
Number of Shares, Vested	(266,896)
Number of Shares, Forfeited	(18,396)
Number of Shares, Unvested ending balance	772,157	730,146
Weighted-Average Grant-Date Fair Value, Unvested beginning balance	$ 39.89
Weighted-Average Grant-Date Fair Value, Granted	54.40	$ 36.10	$ 47.10
Weighted-Average Grant-Date Fair Value, Vested	38.29
Weighted-Average Grant-Date Fair Value, Forfeited	54.74
Weighted-Average Grant-Date Fair Value, Unvested ending balance	$ 44.95	$ 39.89

Stock-Based and Long-term In100

Stock-Based and Long-term Incentive Compensation Plans - Summary of Our Performance Shares (Details) - Performance Share Awards [Member] - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Unvested beginning balance	576,166
Number of Shares, Granted	97,205
Number of Shares, Vested	(201,324)
Number of Shares, Forfeited	(17,971)
Number of Shares, Unvested ending balance	454,076	576,166
Weighted-Average Grant-Date Fair Value, Unvested beginning balance	$ 27.30
Weighted-Average Grant-Date Fair Value, Granted	54.20	$ 37.21	$ 47.48
Weighted-Average Grant-Date Fair Value, Vested	32.07
Weighted-Average Grant-Date Fair Value, Forfeited	43.03
Weighted-Average Grant-Date Fair Value, Unvested ending balance	$ 43.63	$ 27.30

Profit Sharing, Incentive an101

Profit Sharing, Incentive and Retirement Plans - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Profit Sharing And Incentive Plans Details [Abstract]
Accrual for profit sharing and incentive plans liabilities	$ 26.9	$ 22.1
Profit sharing and incentive plans expense recognized	$ 26.9	21.8	$ 28.5
Retirement Plans Details [Abstract]
Matching contributions vesting period	Employee contributions in the plan are vested at all times and our matching contributions are subject to a three-year cliff vesting provision, except for employees who are represented by a collective bargaining agreement and are subject to a three-year graded vesting provision.
401(k) compensation expense	$ 10.9	$ 10.5	$ 9.5

Stock Repurchases - Additional

Stock Repurchases - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Nov. 30, 2013	Dec. 31, 2008
Treasury Stock Details [Abstract]
Amount authorized for the repurchase of common stock					$ 100
Treasury stock repurchase incremental authorization				$ 51
Shares of treasury stock acquired under the repurchase program	3,307,911
Cumulative cost of treasury shares repurchased	$ 126	$ 126
Treasury stock repurchase remaining authorization	$ 25	$ 25
Treasury stock shares acquired from management vests		195,831	297,569
Average cost per share of treasury stock acquired from management		$ 54.20	$ 37.89

Earnings Per Share - Calculatio

Earnings Per Share - Calculations of Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Numerator:
Income from continuing operations, net of taxes									$ 224,338	$ 42,625	$ 7,286
Denominator:
Basic EPS weighted average shares outstanding									25,241	24,843	24,833
Effect of dilutive convertible notes									27
Effect of dilutive stock options and restricted stock									586	277	185
Diluted EPS weighted average shares outstanding									25,854	25,120	25,018
Earnings per share from continuing operations:
Basic	$ 8.28	$ (0.96)	$ 1.55	$ 0	$ 1.15	$ (0.30)	$ 0.84	$ 0.02	$ 8.89	$ 1.72	$ 0.29
Diluted	6.71	(0.96)	0.92	0	1.12	(0.30)	(0.26)	0.02	8.68	1.70	0.29
Loss per share from discontinued operations:
Basic	0	0	0	(0.03)	(0.01)	(0.02)	(0.01)	0	(0.03)	(0.04)	0
Diluted	0	0	0	(0.03)	(0.01)	(0.02)	(0.01)	0	(0.03)	(0.04)	0
Earnings per share:
Basic	8.28	(0.96)	1.54	(0.03)	1.14	(0.32)	0.83	0.02	8.85	1.67	0.29
Diluted	$ 6.71	$ (0.96)	$ 0.92	$ (0.03)	$ 1.11	$ (0.32)	$ (0.28)	$ 0.02	$ 8.64	$ 1.65	$ 0.29

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Restricted shares and units in which performance or market conditions were not satisfied	6.8	7.5	0.3
Warrants and Stock Options [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from the calculation of diluted EPS	7.8	3.3	3

Accumulated Other Comprehens105

Accumulated Other Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	$ 1,517,338	$ 1,454,183	$ 1,417,795
Reclassification to interest expense	1,621	1,770	6,129
Income tax expense	(621)	(700)	(2,277)
Ending Balance	1,789,856	1,517,338	1,454,183
Interest Rate Derivatives [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(5,002)	(6,072)
Reclassification to interest expense	1,621	1,770
Income tax expense	(621)	(700)
Ending Balance	(4,002)	(5,002)	(6,072)
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	9	9
Income tax expense	0	0
Ending Balance	9	9	9
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning Balance	(4,993)	(6,063)	(9,572)
Ending Balance	$ (3,993)	$ (4,993)	$ (6,063)

Accumulated Other Comprehens106

Accumulated Other Comprehensive Income (Loss) - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income Loss [Abstract]
Unamortized realized loss in Accumulated other comprehensive income (loss) related to forward-starting interest rate swaps	$ 6.5
Net realized losses reclassified into earnings	1.6	$ 1.8
Realized losses related to forward-starting interest rate swaps expected to be reclassified into earnings within the next 12 months	$ 1.5

Selected Quarterly Financial107

Selected Quarterly Financial Information (Unaudited) - Summary of Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Selected Quarterly Financial Information Detail [Abstract]
Total Operating Revenue	$ 627,952	$ 535,748	$ 517,366	$ 475,394	$ 529,725	$ 448,015	$ 443,272	$ 418,615
Operating Income	106,748	52,712	58,478	24,036	101,432	25,998	20,824	20,057
Income (Loss) from continuing operations, net of taxes	209,454	(24,195)	39,044	35	28,736	(7,501)	20,919	471
Loss from discontinued operations, net of taxes	(6)	33	(105)	(787)	(319)	(445)	(345)	0	$ (865)	$ (1,109)	$ 0
Net Income (Loss)	$ 209,448	$ (24,162)	$ 38,939	$ (752)	$ 28,417	$ (7,946)	$ 20,574	$ 471
Earnings (Loss) per share from continuing operations:
Basic	$ 8.28	$ (0.96)	$ 1.55	$ 0	$ 1.15	$ (0.30)	$ 0.84	$ 0.02	$ 8.89	$ 1.72	$ 0.29
Diluted	6.71	(0.96)	0.92	0	1.12	(0.30)	(0.26)	0.02	8.68	1.70	0.29
Loss per share from discontinued operations:
Basic	0	0	0	(0.03)	(0.01)	(0.02)	(0.01)	0	(0.03)	(0.04)	0
Diluted	0	0	0	(0.03)	(0.01)	(0.02)	(0.01)	0	(0.03)	(0.04)	0
Earnings (Loss) per share:
Basic	8.28	(0.96)	1.54	(0.03)	1.14	(0.32)	0.83	0.02	8.85	1.67	0.29
Diluted	$ 6.71	$ (0.96)	$ 0.92	$ (0.03)	$ 1.11	$ (0.32)	$ (0.28)	$ 0.02	$ 8.64	$ 1.65	$ 0.29

Selected Quarterly Financial108

Selected Quarterly Financial Information (Unaudited) - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017
Selected Quarterly Financial Information Narrative Detail [Abstract]
Special Charge					$ 3.5			$ 6.6
Unrealized gain (loss) on financial instruments	$ 23.7	$ (44.8)	$ 13.8	$ (5.2)	(27.9)	$ (1.5)	$ 26.5
Income tax benefit related to the U.S. tax cuts and jobs act	$ 130								$ 130
Transaction-related expenses					$ 0.6	3.9	16.8
Accrual for legal matters							$ 6.7
Compensation costs related to a change in control						$ 26.2

Schedule II - Valuation and 109

Schedule II - Valuation and Qualifying Accounts (Details) - Allowance for Doubtful Accounts [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 997	$ 1,247	$ 1,658
Additions Charged to Costs and Expenses	198	508	171
Deductions, net of recoveries	299	(758)	(582)
Balance at End of Period	$ 1,494	$ 997	$ 1,247