PHI (PHIG) 10-K 18 Mar 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2018	Mar. 07, 2019	Jun. 29, 2018
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Trading Symbol	PHII
Entity Registrant Name	PHI INC
Entity Central Index Key	0000350403
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Shell Company	false
Entity Filer Category	Accelerated Filer
Entity Public Float			$ 161,759,638
Voting Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		2,905,757
Non-Voting Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		12,919,681

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 50,874	$ 8,770
Short-term investments	14,232	64,237
Accounts receivable – net
Trade	168,459	168,153
Other	14,006	17,826
Inventories of spare parts – net	56,698	80,881
Prepaid expenses	11,419	11,475
Income taxes receivable	950	1,271
Total current assets	316,638	352,613
Property and equipment – net	902,485	946,765
Restricted cash and investments	19,781	12,396
Other assets	18,378	8,741
Deferred income taxes	4,944	3,309
Goodwill	0	61,299
Intangibles	0	16,723
Total assets	1,262,226	1,401,846
Current Liabilities:
Senior Notes issued March 17, 2014, net of unamortized debt issuance costs of $260	499,740	0
Accounts payable	50,289	37,186
Accrued and other current liabilities	45,292	41,850
Total current liabilities	595,321	79,036
Long-term debt:
Revolving credit facility	0	117,500
Senior Notes issued March 17, 2014, net of unamortized debt issuance costs of $1,506	0	498,494
Related Party Term Loan issued September 28, 2018, net of debt issuance costs of $765	129,235	0
Deferred income taxes	59,178	86,005
Other long-term liabilities	5,059	8,157
Commitments and contingencies (Note 13)
Shareholders’ Equity:
Additional paid-in capital	314,316	308,353
Accumulated other comprehensive loss	(3,952)	(280)
Retained earnings	161,487	303,001
Total shareholders’ equity	473,433	612,654
Total liabilities and shareholders’ equity	1,262,226	1,401,846
Voting Common Stock [Member]
Shareholders’ Equity:
Common stock	291	291
Non-Voting Common Stock [Member]
Shareholders’ Equity:
Common stock	$ 1,291	$ 1,289

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt issuance costs, current	$ 260
Debt issuance costs, noncurrent	$ 1,506
Voting Common Stock [Member]
Common stock, par value	$ 0.10	$ 0.10
Common stock, shares authorized	12,500,000	12,500,000
Common stock, shares issued	2,905,757	2,905,757
Common stock, shares outstanding	2,905,757	2,905,757
Non-Voting Common Stock [Member]
Common stock, par value	$ 0.10	$ 0.10
Common stock, shares authorized	37,500,000	37,500,000
Common stock, shares issued	12,919,681	12,897,614
Common stock, shares outstanding	12,919,681	12,897,614
Related Party Term Loan [Member]
Debt issuance costs, noncurrent	$ 765

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Operating revenues, net	$ 674,423	$ 579,545	$ 634,098
Expenses:
Direct expenses	631,807	546,699	592,550
Selling, general and administrative expenses	66,685	53,817	44,418
Total operating expenses	698,492	600,516	636,968
Loss (gain) on disposition of assets, net	753	298	(3,350)
Impairments of assets	109,024	368	407
Equity in loss (profit) of unconsolidated affiliate	(188)	385	(151)
Operating (loss) income	(133,658)	(22,022)	224
Interest expense	33,981	32,183	30,644
Other income, net	(179)	(2,764)	(3,271)
Total expenses	33,802	29,419	27,373
(Loss) earnings before income taxes	(167,460)	(51,441)	(27,149)
Income tax (benefit) expense	(25,946)	(58,973)	(469)
Net earnings (loss)	$ (141,514)	$ 7,532	$ (26,680)
Earnings (loss) per share:
Basic (USD per share)	$ (8.95)	$ 0.48	$ (1.70)
Diluted (USD per share)	$ (8.95)	$ 0.48	$ (1.70)
Weighted average shares outstanding:
Basic (shares)	15,818	15,762	15,663
Diluted (shares)	15,818	15,762	15,663

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net earnings (loss)	$ (105,907)	$ (11,531)	$ (7,093)	$ (16,983)	$ 29,330	$ (3,277)	$ (3,273)	$ (15,248)	$ (141,514)	$ 7,532	$ (26,680)
Net unrealized gain (loss) on short-term investments									364	310	241
Changes in pension plan assets and benefit obligations									(1)	(3)	(39)
Tax effect of the above-listed adjustments									(85)	(109)	(113)
Currency translation adjustment									(3,950)	0	0
Total comprehensive income (loss)									$ (145,186)	$ 7,730	$ (26,591)

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]Voting Common Stock [Member]	Common Stock [Member]Non-Voting Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]
Balance at Dec. 31, 2015	$ 626,998	$ 291	$ 1,269	$ 304,884	$ (567)	$ 321,121
Balance, Shares at Dec. 31, 2015		2,906	12,685
Net earnings (loss)	(26,680)					(26,680)
Unrealized loss on short-term investments	113				113
Changes in pension plan assets and benefit obligations	(24)				(24)
Amortization of unearned stock-based compensation	4,819			4,819
Currency translation	0
Issuance of non-voting common stock (upon vesting of restricted stock units)	12		$ 12
Issuance of non-voting common stock (upon vesting of restricted stock units), shares			130
Cancellation of restricted non-voting stock units for tax withholdings on vested shares	(531)		$ (3)	(528)
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, shares			(28)
Purchase and retirement of treasury stock	(4,929)			(4,929)
Other, shares			(8)
Balance at Dec. 31, 2016	599,778	$ 291	$ 1,278	304,246	(478)	294,441
Balance, Shares at Dec. 31, 2016		2,906	12,779
Net earnings (loss)	7,532					7,532
Unrealized loss on short-term investments	200				200
Changes in pension plan assets and benefit obligations	(2)				(2)
Amortization of unearned stock-based compensation	4,374			4,374
Currency translation	0
Cumulative effect adjustment of unrecognized tax benefits	1,028					1,028
Issuance of non-voting common stock (upon vesting of restricted stock units)	0		$ 11	(11)
Issuance of non-voting common stock (upon vesting of restricted stock units), shares			140
Cancellation of restricted non-voting stock units for tax withholdings on vested shares	(256)			(256)
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, shares			(22)
Other	0				0
Other, shares			0
Balance at Dec. 31, 2017	612,654	$ 291	$ 1,289	308,353	(280)	303,001
Balance, Shares at Dec. 31, 2017		2,906	12,897
Net earnings (loss)	(141,514)					(141,514)
Unrealized loss on short-term investments	279				279
Changes in pension plan assets and benefit obligations	(1)				(1)
Amortization of unearned stock-based compensation	6,070			6,070
Currency translation	(3,950)				(3,950)
Issuance of non-voting common stock (upon vesting of restricted stock units)	2		$ 2
Issuance of non-voting common stock (upon vesting of restricted stock units), shares			33
Cancellation of restricted non-voting stock units for tax withholdings on vested shares	(107)			(107)
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, shares			(11)
Balance at Dec. 31, 2018	$ 473,433	$ 291	$ 1,291	$ 314,316	$ (3,952)	$ 161,487
Balance, Shares at Dec. 31, 2018		2,906	12,919

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating activities:
Net earnings (loss)		$ (141,514)	$ 7,532	$ (26,680)
Adjustments to reconcile net earnings (loss) to net cash (used in) provided by operating activities:
Depreciation and amortization		79,254	68,027	65,743
Deferred income taxes		(28,552)	(59,272)	(2,424)
Gain (loss) on asset dispositions		753	298	(3,350)
Equity in loss (income) of unconsolidated affiliate		(188)	385	(151)
Impairment of assets		109,024	368	407
Inventory valuation reserves		2,230	2,410	5,179
Changes in operating assets and liabilities:
Accounts receivable	[1]	3,788	(28,329)	(351)
Inventories of spare parts	[1]	4,328	(6,793)	(5,064)
Income taxes receivable	[1]	320	186	220
Other assets	[1]	(21,105)	(9,050)	(14,837)
Accounts payable and accrued liabilities	[1]	16,812	5,754	(19,111)
Other long-term liabilities	[1]	(7,502)	(619)	(142)
Net cash (used in) provided by operating activities	[1]	17,648	(19,103)	(564)
Investing activities:
Purchase of property and equipment		(43,176)	(56,757)	(81,842)
Proceeds from asset dispositions		14,245	1,296	14,983
Purchase of short-term investments		(284,481)	(637,980)	(321,453)
Proceeds from sale of short-term investments		334,488	862,942	316,543
Payments of deposits on aircraft		0	0	(2,249)
Loan to unconsolidated affiliate		(274)	0	(1,200)
Loan to third party		0	(824)	0
Business acquisitions net of cash acquired		0	(126,644)	0
Net cash provided by (used in) investing activities		20,802	42,033	(75,218)
Financing activities:
Debt Issuance costs		(874)	0	0
Repurchase of common stock		(106)	(256)	(529)
Proceeds from line of credit		34,295	152,150	264,700
Payments on line of credit		(151,795)	(168,650)	(188,200)
Proceeds from related party term loan		130,000	0	0
Net cash provided by (used in) financing activities		11,520	(16,756)	75,971
Effect of exchange rate changes on cash and cash equivalents		(176)	0	0
Increase (decrease) in cash, cash equivalents and restricted cash		49,794	6,174	189
Cash, cash equivalents and restricted cash at beginning of period		8,770	2,596	2,407
Cash, cash equivalents and restricted cash at end of period		58,564	8,770	2,596
Cash paid during the period for:
Interest		30,828	30,517	29,169
Income Taxes		2,273	1,231	2,637
Accrued payables related to purchases of property and equipment		$ 52	$ 42	$ 29
[1]	Net of the effect of business acquisitions.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Nature of Operations, Basis of Consolidation, and Other General Principles PHI, Inc. and its subsidiaries (“PHI,” the “Company,” “we,” “us,” or “our”) provide transportation services to, from, and among offshore facilities for customers engaged in the oil and gas exploration, development, and production industry. We provide these offshore services primarily in the United States and to a lesser extent in Canada, Trinidad, Australia, New Zealand, the Philippines, West Africa and the Middle East. We also provide air medical transportation services for hospitals and emergency service agencies, as well as aircraft maintenance and repair services to third parties in North America. The consolidated financial statements include the accounts of PHI, Inc. and its subsidiaries after the elimination of all intercompany accounts and transactions. We apply the equity method of accounting for investments in entities, if we have the ability to exercise significant influence over the operating and financial policies of the entity. We report our share of earnings or losses of equity investees in the accompanying Consolidated Statements of Operations as equity in (loss) profit of unconsolidated affiliate. At December 31, 2018 , Al A. Gonsoulin, Chairman of the Board and Chief Executive Officer, beneficially owned stock representing approximately 70.9% of the total voting power. As a result, he exercises control over the election of PHI’s directors and the outcome of matters requiring a shareholder vote. Chapter 11 Cases As of December 31, 2018, the Company’s total senior indebtedness was $630 million , consisting of (i) $500.0 million principal amount of our 5.25% Senior Notes due March 15, 2019 and (ii) $130.0 million principal amount of borrowings under its two -year term loan with the financing affiliate of its controlling shareholder (in each case excluding debt issuance costs). The Company also had $19.8 million of letters of credit outstanding at December 31, 2018. As of December 31, 2018, the Company had approximately $159.5 million of aggregate lease commitments. As discussed further elsewhere herein, the Company borrowed an additional $70 million on March 13, 2019. Beginning in late 2017, the Company considered its options for refinancing its unsecured senior notes due March 15, 2019. However, in light of the challenging operating environment for companies providing offshore energy services generally, the financing market was constrained and the Company was not able to identify a refinancing option that it believed provided a suitable capital platform to promote the best interests of the Company and its stakeholders. In the fall of 2018, the Company announced that it had engaged financial advisors to assist the Company in exploring and evaluating a broad range of potential strategic alternatives. After working closely with the Company’s advisors, communicating with the Company’s various stakeholders, and carefully evaluating all possible options, the Board concluded that pursuing Chapter 11 protection was the most appropriate course of action to address the Company’s maturing debt and strengthen its balance sheet. Prior to the maturity of the Company’s unsecured senior notes, on March 14, 2019 (the “Petition Date”), the Company and its principal U.S. subsidiaries. PHI Tech Services, Inc., AM Equity Holdings, L.L.C., PHI Air Medical, L.L.C. and PHI Helipass, L.L.C. (together with the Company, collectively, the “Debtors”) filed voluntary petitions (the “Chapter 11 Cases”) in the United States Bankruptcy Court for the Northern District of Texas (the “Bankruptcy Court”) seeking relief under Chapter 11 of Title 11 of the United States Code (the “Bankruptcy Code”). The Debtors have requested joint administration of their Chapter 11 Cases under the caption In re: PHI, Inc., et al., Main Case No. 19-30923. The Debtors continue to operate their businesses and manage their properties as “debtors-in-possession” under the jurisdiction of the Bankruptcy Court and in accordance with the applicable provisions of the Bankruptcy Code and orders of the Bankruptcy Court. To ensure their ability to continue operating in the ordinary course of business, the Debtors have filed with the Bankruptcy Court motions seeking a variety of “first-day” relief (collectively, the “First Day Motions”), including authority to pay employee wages and benefits, honor customer programs, and pay utilities providers, insurance providers and other vendors and suppliers in the ordinary course for all goods and services provided after the Petition Date. We currently retain the exclusive right to propose a Chapter 11 plan of reorganization. If the Bankruptcy Court terminates that right, however, or the exclusivity period expires, our ability to achieve confirmation of a Chapter 11 plan of reorganization could be materially adversely affected. Going Concern The Company expects to continue operations in the normal course during the pendency of the Chapter 11 Cases described immediately above under the heading "Chapter 11 Cases". The significant risks and uncertainties related to the company’s Chapter 11 Case raise substantial doubt about the company's ability to continue as a going concern. The consolidated financial statements have been prepared on a going concern basis of accounting, which contemplates continuity of operations, realization of assets, and satisfaction of liabilities and commitments in the normal course of business. The consolidated financial statements do not include any adjustments that might result from the outcome of the going concern uncertainty. See Note 19 for further information and details on the Company’s restructuring and Chapter 11 proceedings. Use of Estimates The preparation of financial statements is in conformity with accounting principles generally accepted in the United States of America (“GAAP”), which requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates. Significant estimates include: Estimates of contractual allowances applicable to billings in the Air Medical segment, Valuation reserve related to obsolete and excess inventory, Reserves related to unpaid accounts, Depreciable lives and salvage values of property and equipment, Valuation allowance for deferred tax assets, Fair values of assets acquired and liabilities assumed, Income taxes, Healthcare insurance claims and workers’ compensation liability, and Impairment of long-lived assets, Impairment of Goodwill and Intangible assets. Cash and Cash Equivalents We consider all highly liquid investments with maturities of three months or less , when purchased, to be cash equivalents. Trade Receivables, net Trade and other receivables are stated at net realizable value. Air Medical trade receivables are presented net of allowances for contractual discounts and uncompensated care. We estimate contractual allowances and uncompensated care based on historical collection experience by payor category. The main payor categories are Medicare, Medicaid, private insurance, and self-pay. We analyze our historical payment of accounts by payor category on a monthly basis, and adjust our accounts receivable allowance based upon each category’s historical collection percentage plus any adjustments for current trends in payor behavior. Provisions for contractual discounts and uncompensated care that we applied to our Air Medical trade receivables (expressed as a percentage of total segment accounts receivable at December 31 were as follows: 2018 2017 Allowance for contractual discounts 51% 53% Allowance for uncompensated care 22% 24% Short-term Investments Short-term investments consist of commercial paper, debt issued by the U.S. government or its agencies, and corporate bonds and notes, which represent funds available for current operations. In accordance with GAAP, these short-term investments are classified as available for sale. Inventories of Spare Parts The Company’s inventories are stated at average cost and consist primarily of spare aircraft parts. Portions of the Company’s inventories are used parts that are often exchanged with parts removed from aircraft, reworked to a useable condition according to manufacturers’ and FAA specifications, and returned to inventory. Reusable aircraft parts are included in inventory at the average cost of comparable parts. The rework costs are expensed as incurred. The Company also records an allowance for obsolete and slow-moving parts, relying principally on specific identification of such inventory. Valuation reserves related to obsolescence and slow-moving inventory were $17.9 million and $20.9 million at December 31, 2018 and 2017 , respectively. Property and Equipment The Company records its property and equipment at cost less accumulated depreciation. For financial reporting purposes, the Company uses the straight-line method to compute depreciation based upon estimated useful lives of 5 to 15 years for flight equipment and 3 to 10 years for other equipment. Leasehold improvements are amortized over the shorter of the life of the respective asset or the term of the lease agreement and range from 6 to 10 years. The salvage value used in calculating depreciation of aircraft ranges from 25% to 54% of the aircraft’s carrying value, based upon historical aircraft sales data. The cost of scheduled inspections and modifications for flight equipment are charged to maintenance expense as incurred. We charge maintenance and repair costs to earnings as the costs are incurred. The cost of certain aircraft components are covered under contractual arrangements with the applicable aircraft manufacturer, commonly referred to as “power-by-the-hour” contracts. Under these agreements, we are charged an agreed amount per hour of flying time. The costs charged under these contractual arrangements are recognized in the period in which the flight hours occur. To the extent that we have not yet been billed for costs incurred under these arrangements, these costs are included in accrued expenses on our consolidated balance sheets. Modifications that enhance the operating performance or extend the useful lives of the aircraft are capitalized and depreciated over the remaining life of the aircraft. Upon selling or otherwise disposing of property and equipment, the Company removes the cost and accumulated depreciation from the accounts and reflects any resulting gain or loss in earnings at the time of sale or other disposition. The Company reviews its long-lived tangible assets for impairment annually, or more frequently if events or a change of circumstances indicate that an impairment may have occurred. In such evaluation, the estimated future undiscounted cash flows generated by a particular asset group are compared with the book value of the asset group to determine if an impairment charge is necessary. Similar aircraft model types are grouped together for impairment testing purposes. The Company measures recoverability of assets to be held and used by comparing the carrying amount of an asset to future undiscounted net cash flows that it expects the asset to generate. When the Company determines that an asset is impaired, the Company recognizes that impairment amount, which is measured by the amount that the carrying value of the asset exceeds its fair value. In addition to the periodic review of its active long-lived tangible assets for impairment when circumstances warrant, the Company also performs a review of its parked aircraft not expected to return to service annually or whenever changes in circumstances indicate the carrying amount of an aircraft may not be recoverable. Management estimates the fair value of each aircraft not expected to return to service by considering items such as the aircraft’s age, length of time parked, likelihood of return to active service, and actual recent sales of similar aircraft. For more significant aircraft carrying values, we obtain an estimate of the fair value of the parked aircraft from third-party appraisers for use in our determination of fair value estimates. The Company records an impairment charge when the carrying value of a parked aircraft not expected to return to active service exceeds its estimated fair market value. During the twelve months ended December 31, 2018 , we sold or disposed of one heavy, three medium and one light aircraft and related parts inventory utilized in our Oil and Gas segment and one light aircraft in our Air Medical segment. Cash proceeds totaled $14.2 million , resulting in a loss of $0.8 million . These aircraft no longer met our strategic needs. During the twelve months ended December 31, 2017 , we sold or disposed of six medium, one fixed wing aircraft and related parts inventory previously utilized in our Oil and Gas segment. Cash proceeds totaled $ 1.3 million , resulting in a loss of $ 0.3 million . These aircraft no longer met our strategic needs. During the twelve months ended December 31, 2016, we sold twelve light, eleven medium aircraft, and related parts inventory previously utilized in our Oil and Gas segment. Cash proceeds totaled $15.0 million , resulting in a gain of $3.3 million . These aircraft no longer met our strategic needs. Impairment Losses for Aircraft The Company estimates cash flows and asset appraisals based upon historical data adjusted for the Company’s best estimate of expected future market performance. If an asset group fails the undiscounted cash flow test or appraisal value, the Company compares the market value to the book value of each asset group in order to determine if impairment exists (considered Level 3, as defined by ASC 820, Fair Value Measurements and Disclosures). If impairment exists, the book value of the asset group is reduced to its estimated fair value. We recorded an impairment loss in the year ended December 31, 2018 for two light, seventeen medium and one heavy aircraft and related spare parts in our Oil and Gas segment. The carrying value of these aircraft was $109.6 million . Following a market analysis, we determined that the market value for these aircraft is $85.2 million (based on a Level 3 review, as defined by ASC 820, Fair Value Measurements and Disclosures). As a result of this analysis, we recorded an aggregate non-cash pre-tax impairment loss of $23.2 million for 2018 . We had $0.4 million impairment losses in the year ended December 31, 2017 . We had $0.4 million impairment losses for the year ended December 31, 2016 . (see note 18) Fair Value of Assets and Liabilities Acquired and Identification of Associated Goodwill and Intangible Assets In conjunction with each acquisition we make, we must allocate the cost of the acquired entity to the assets and liabilities assumed based on their estimated fair values at the date of acquisition. As additional information becomes available, we may adjust the original estimates within a short time period subsequent to the acquisition. In addition, we are required to recognize intangible assets separately from goodwill. Determining the fair value of assets and liabilities acquired, as well as intangible assets that relate to such items as customer relationships, contracts, trade names and non-compete agreements involves professional judgment and is ultimately based on acquisition models and management’s assessment of the value of the assets acquired, and to the extent available, third party assessments. Intangible assets with finite lives are amortized over their estimated useful life as determined by management. Whenever events or changes in circumstances indicate that the carrying amount of the intangible assets may not be recoverable, the intangible assets will be reviewed for impairment. Goodwill is not amortized but instead is periodically assessed for impairment. Uncertainties associated with these estimates include fluctuations in economic obsolescence factors in the area and potential future sources of cash flow. We cannot provide assurance that actual amounts will not vary significantly from estimated amounts. (see note 2) Goodwill Goodwill represents the amount the purchase price exceeds the fair value of net assets acquired in a business combination. Goodwill has an indefinite useful life and is not amortized, but is assessed for impairment annually or when events or changes in circumstances indicate that a potential impairment exists. The Company performs the goodwill impairment test on an annual basis during the fourth quarter or on an interim basis if events or circumstances indicate that the fair value of the asset has decreased below its carrying value. The company performed its goodwill impairment test in the fourth quarter. In order to estimate the fair value of the reporting units (which is consistent with the reported business segments), the Company used a weighting of the discounted cash flow method and the public company guideline method of determining fair value of each reporting unit. The Company weighted the discounted cash flow method 80% and the public company guideline method 20% due to differences between the Company’s reporting units and the peer companies’ size, profitability and diversity of operations. These fair value estimates were then compared to the carrying value of the reporting units. If the fair value of the reporting unit exceeds the carrying amount, no impairment loss is recognized. If the estimated fair value of the reporting unit is below the carrying value, then an impairment is recorded, which represents the amount by which a reporting unit’s carrying value exceeds its fair value. The inputs used to determine fair value were classified as level 3 in the fair value hierarchy. A significant amount of judgment was involved in performing these evaluations since the results are based on estimated future events. At December 31, 2018, the Company’s accumulated impairments of goodwill was $61.6 million . As of December 31, 2018 there is no remaining goodwill in our financial statements. (see note 18). Other Intangible Assets In connection with our acquisition of the HNZ Offshore Business, we also recognized in the fourth quarter of 2017 intangible assets for customer relationship, non-compete and tradenames. Intangible assets with finite useful lives are amortized over estimated useful lives on a straight-line basis. The Company reviews its intangible assets for impairment annually, or more frequently if events or a change of circumstances indicate that the carrying amount of any such asset may not be recoverable. The determination of recoverability is made based upon the estimated undiscounted future net cash flows. In such evaluation, the estimated future undiscounted cash flows generated by a particular asset group are compared with the book value of the asset group to determine if an impairment charge is necessary. The Company measures recoverability of assets to be held and used by comparing the carrying amount of an asset to future undiscounted net cash flows that it expects the asset to generate. When the Company determines that an asset is impaired, the Company recognizes that impairment amount, which is measured by the amount that the carrying value of the asset exceeds its fair value. The estimated fair values for these assets were determined using discounted future cash flows. The significant level 3 unobservable inputs used in the determination of the fair value of these assets were the estimated future cash flows and the weighted average cost of capital ("WACC"). During the fourth quarter of 2018, the Company recorded $15.5 million in impairments of values of intangibles in the Oil & Gas segment (see note 18) Our intangible assets by types consist of the following (in thousands): Estimated Useful Lives Gross Amount Accumulated Amortization Impairments of assets Net Balance Customer Relationship 15 11,622 (581 ) (11,041 ) — Non-Compete Agreements 5 900 (135 ) (765 ) — Tradenames 7 4,201 (450 ) (3,751 ) — Total 16,723 (1,166 ) (15,557 ) — Deferred Financing Costs Costs incurred to obtain long-term debt financing are deferred and amortized ratably over the term of the related debt agreement. Self-Insurance The Company maintains a self-insurance program for a portion of its healthcare costs. Self-insurance costs are accrued based upon the aggregate of the liability for reported claims and the estimated liability for claims incurred but not reported. The Company’s insurance retention was $250,000 per claim through December 31, 2018 . As of December 31, 2018 and 2017 , the Company had $1.8 million and $1.3 million , respectively, of accrued liabilities related to healthcare claims. There is also a $0.5 million deductible per incident on our workers’ compensation program. We have accrued $1.9 million and $2.9 million for the years 2018 and 2017 , respectively, related to workers’ compensation claims. The Company owns an offshore insurance company to realize savings in reinsurance costs on its insurance premiums. We paid $0.3 million and $0.5 million , respectively, to this captive company in 2018 and 2017 , which were eliminated in consolidation. The results of the captive are fully consolidated in the accompanying consolidated financial statements. Revenue Recognition In 2014, the Financial Accounting Standard Board ("the FASB") issued ASC 606, Revenue from Contracts with Customers (“ASC 606”), replacing the existing accounting standard and industry specific guidance for revenue recognition with a five-step model for recognizing and measuring revenue from contracts with customers. The underlying principle of the new standard is to recognize revenue to depict the transfer of goods or services to customers at the amount expected to be collected. ASC 606 became effective on January 1, 2018 and we adopted it using the modified retrospective method applied to open contracts and only to the version of the contracts in effect as of January 1, 2018. Prior period amounts have not been adjusted and continue to be reflected in accordance with our historical accounting. There was no impact on the condensed consolidated financial statements and no cumulative effect adjustment was recognized. In general, under ASC 606, we recognize revenue when a service or good is sold to a customer and there is a contract. At contract inception, we assess the goods and services promised in our contracts with customers and identify all performance obligations for each distinct promise that transfers a good or service (or bundle of goods or services) to the customer. To identify the performance obligations, we consider all goods or services promised in the contract, whether explicitly stated or implied based on customary business practices. Revenue is recognized when control of the identified distinct goods or services has been transferred to the customer, the transaction price has been determined and allocated to the performed performance obligations and we have determined that collection has occurred or is probable of occurring. We measure revenue as the amount of consideration we expect to receive in exchange for the services provided. Taxes collected from customers and remitted to governmental authorities and revenues are reported on a net basis in the financial statements. Thus, we exclude taxes imposed on the customer and collected on behalf of governmental agencies to be remitted to these agencies from the transaction price in determining the revenue related to contracts with a customer. Oil & Gas Revenue Recognition - We provide helicopter services to oil and gas customers operating in the Gulf of Mexico and a number of foreign countries. Revenues are recognized when performance obligations are satisfied over time in accordance with contractual terms, in an amount that reflects the consideration the Company expects to be entitled to in exchange for services rendered. Air Medical Revenue Recognition - We provide helicopter services to hospitals and emergency service providers in several U.S. states, or to individual patients in the U.S. in which case we are paid by either a commercial insurance company, federal or state agency, or the patient. Our Air Medical segment operates primarily under the independent provider model and, to a lesser extent, under the traditional provider model. Revenues related to the independent provider model services are recorded in the period in which we satisfy our performance obligations under contracts by providing our services to our customers based upon established billing rates net of contractual allowances under agreements with third party payors and net of uncompensated care allowances. These amounts are due from patients, third-party payors (including health insurers and government programs), and others and includes variable consideration for retroactive revenue adjustments due to settlement of audits, reviews, and investigations. Generally, we bill the patients and third-party payors several days after the services are performed. Revenues generated under the traditional provider model are recognized as performance obligations are satisfied over time in accordance with contractual terms, in an amount that reflects the consideration the Company expects to be entitled in exchange for services rendered. Oil & Gas Performance Obligations - A performance obligation arises under contracts with customers to render services and is the unit of account under ASC 606. Operating revenue from our Oil and Gas segment is derived mainly from fixed-term contracts with our customers, a substantial portion of which are competitively bid. A small portion of our Oil and Gas segment revenue is derived from providing services on an "ad-hoc" basis. Our fixed-term contracts typically have original terms of one to seven years (subject to provisions permitting early termination on relatively short notice by the customers), with payment in U.S. dollars. We account for services rendered separately if they are distinct and the services are separately identifiable from other items provided to a customer and if a customer can benefit from the services rendered on its own or with other resources that are readily available to the customer. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. Within this contract type for helicopter services, we determined that each contract has a single distinct performance obligation. These services include a fixed monthly rate for a particular model of aircraft, and flight hour services, which represents the variable component of a typical contract with a customer. Rates for these services vary depending on the type of services provided and can be based on a per flight hour, per day, or per month basis. We also provide services to clients on an “ad hoc” basis, which usually entails a shorter contract notice period and duration. The charges for ad hoc services are based on an hourly rate or a daily or monthly fixed fee plus additional fees for each hour flown. The nature of our variable charges within our flight services contracts are not effective until a customer-initiated flight order and the actual hours flown are determined; therefore, the associated flight revenue generally cannot be reasonably and reliably estimated beforehand. A contract’s standalone selling prices are determined based upon the prices that we charge for our services rendered. The majority of our revenue is recognized as performance obligations satisfied over time, by measuring progress towards satisfying the contracted services in a manner that best depicts the transfer of services to the customer, which is generally represented by a period of 30 days or less. We typically invoice customers on a monthly basis with the term between invoicing and when the payment is due typically being between 30 and 60 days. Air Medical Performance Obligations - Performance obligations are determined based upon the nature of the services provided. Under the independent provider model, we measure the performance obligation from the moment the patient is loaded into the aircraft until it reaches its destination. Under this model, we have no fixed revenue stream and compete for transport referrals on a daily basis with other independent operators in the area. As an independent provider, we bill for our services on the basis of a flat rate plus a variable charge per patient-loaded mile, regardless of aircraft model, and are typically compensated by private insurance, Medicaid or Medicare, or directly by transported patients who self-pay. We recognize revenues for performance obligations satisfied at a point in time, which generally relate to patients receiving air medical services when: (1) services are provided; and (2) we do not believe the patient requires additional services. For the independent provider model, we determine the transaction price based upon gross charges for services provided reduced by contractual adjustments provided to third-party payors, discounts provided to uninsured patients in accordance with Company policy, and/or implicit price concessions provided to uninsured patients. We determine estimates of contractual adjustments and discounts based upon contractual agreements, our discount policy, and historical experience. We determine our estimate of implicit price concessions based upon our historical collection experience with these classes of patients using a portfolio approach as a practical expedient to account for patient contracts as collective groups, rather than individually. The financial statement effects of using this practical expedient are not materially different from an individual contract approach. Under the traditional provider model, we contract directly with the customer to provide their transportation services. These contracts are typically awarded or renewed through competitive bidding and typically permit early termination by the customer on relatively short notice. As a traditional provider, we typically bill a fixed monthly rate for aircraft availability and an hourly rate for flight time. For each of these types of helicopter services, we have determined that each has a single distinct performance obligation. Traditional provider models services include fixed monthly rate for a particular model of aircraft, and flight hour services, which represents the variable component of a typical contract with a customer. Rates for these services vary depending on the type of services provided and can be based on a per flight hour, per day, or per month basis. The variable charges within such contracts are not effective until the customer initiates a flight order and the actual hours flown are determined; therefore, the associated revenue generally cannot be reasonably and reliably estimated beforehand. For the traditional provider model, we determine the transaction price based upon standard charges for goods and services provided. Independent provider revenues are recorded net of contractual allowances under agreements with third party payors and estimated uncompensated care at the time the services are provided. Contractual allowances and uncompensated care are estimated based on historical collection experience by payor category (consisting mainly of private insurance, Medicaid, Medicare, and self-pay). The allowance percentages calculated are applied to the payor categories, and the necessary adjustments are made to the revenue allowance. Agreements with third-party payors typically provide for payments at amounts less than established charges. We estimate contractual allowances and uncompensated care based on historical collection experience by payor category. The main payor categories are Medicaid, Medicare, private insurance, and self-pay. Changes in payor mix, reimbursement rates and uncompensated care rates are the factors most subject to sensitivity and variability in calculating our allowances. We compute a historical payment analysis of accounts by category. The allowance percentages calculated are applied to the payor categories, and the necessary adjustments are made to the revenue allowance. In our Air Medical Segment, the allowance for contractual discounts against outstanding accounts receivable was $123.8 million , $117.8 million , and $111.9 million as of December 31, 2018 , 2017 , and 2016 , r

Acquisition of Business

Acquisition of Business	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
Acquisition of Business	ACQUISITION OF BUSINESS On December 29, 2017, we completed a series of transactions with HNZ Group, Inc. (“HNZ”) and 2075568 Alberta ULC, a company newly-formed by the former Chief Executive Officer of HNZ for purposes of purchasing the stock of HNZ (the “Canadian Purchaser”). On December 29, 2017, we provided term loans to the Canadian Purchaser in an aggregate principal amount of approximately CAD $167.5 million (equivalent to USD $131.6 million ) substantially all of which was repaid the same date in exchange for receipt of HNZ’s offshore helicopter services business conducted in New Zealand, Australia, the Philippines and Papua New Guinea (the “HNZ Offshore Business”). The remaining balance of USD $0.8 million is expected to be repaid on or prior to December 31, 2019, or at such other time as mutually-agreed between the Canadian Purchaser and us. We funded our term loans to the Canadian Purchaser on December 29, 2017 primarily with the proceeds of maturing or liquidated short-term investments. In the fourth quarter of 2017, we recognized the assets that we acquired and the liabilities that we assumed in connection with the HNZ Offshore Business at their estimated acquisition date fair values. The company recorded approximately $61 million of goodwill which is included in our Oil & Gas segment. See Note 1 for information on goodwill and other intangible assets that we recorded in connection with the acquisition. As of December 31, 2017, we had recognized approximately $2.3 million in cumulative merger-related transaction costs, including legal and advisory fees in the selling, general and administrative expenses section of the accompanying Consolidated Statements of Operations. The fair value of the acquired assets and liabilities noted in the table may change during the provisional period, which may last up to twelve months subsequent to the acquisition date. The Company may obtain additional information to refine the valuation of the acquired assets and liabilities and adjust the recorded fair value. Adjustments recorded to the acquired assets and liabilities will be applied prospectively. The purchase price allocation for this transaction has been finalized. Our finalized purchase price allocation was adjusted by an immaterial amount that was recorded in the consolidated financial statements for the year ended December 31, 2018. The following amounts represent the fair value of assets acquired and liabilities assumed in the merger. Thousands of dollars Cash $ 4,142 Accounts receivable 27,819 Inventories 3,096 Fixed assets 43,689 Intangible assets: Noncompete agreements (weighted-average life of 5 years) 900 Customer relationships (weighted-average life of 15 years) 11,622 Tradenames (weighted-average life of 7 years) 4,201 Other assets 5,310 Accounts payable and accrued liabilities (25,272 ) Deferred taxes (1) (5,270 ) Other liabilities (750 ) Total identifiable net assets 69,487 Goodwill (2) 61,299 Total consideration transferred $ 130,786 (1) In connection with the acquisition accounting, PHI provided deferred taxes related to the estimated fair value adjustments for acquired intangible assets. (2) Goodwill is the excess of purchase price over fair market value of the net assets acquired under the acquisition method of accounting. The amount of goodwill that is deductible for income tax purposes is not significant. During the fourth quarter of 2018, we recorded an impairment charge which eliminated all of this goodwill. We did not record earnings in December 2017 for the acquired business due to the immateriality of the earnings resulting after the acquisition for the last two days of 2017. ASC 805, Business Combinations, requires the disclosure of additional information including the revenue and earnings of the combined entity as though the business combination that occurred during the current year had occurred at the beginning of the prior annual reporting period (supplemental pro forma information). The Company has determined that disclosure of such information was impractical and is not provided as the financial records of the acquiree were not adequate to allow the preparation of supplemental pro forma information.

Investments

Investments	12 Months Ended
	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Investments	INVESTMENTS We classify all of our short term investments as available-for-sale. We carry these at fair value and report unrealized gains and losses, net of taxes, in accumulated other comprehensive (loss) income, which is a separate component of shareholders’ equity in our consolidated balance sheets. These unrealized gains and losses are also reflected in our Condensed Consolidated Statement of Comprehensive Income and Condensed Consolidated Statement of Shareholders' Equity. We determined cost, gains, and losses using the specific identification method. In the years ended December 31, 2018 , 2017 , and 2016 , we received proceeds from the sales of these securities of $334.5 million , $862.9 million , and $316.5 million , respectively. Gains and losses on these sales were negligible and all amounts reclassified from accumulated other comprehensive income were immaterial. Investments consisted of the following as of December 31, 2018 : Cost Basis Unrealized Gains Unrealized Losses Fair Value (Thousands of dollars) Investments: Money market mutual funds $ 26,308 $ — $ — $ 26,308 Deferred compensation plan assets included in other assets 772 — — 772 Total $ 27,080 $ — $ — $ 27,080 Investments consisted of the following as of December 31, 2017 : Cost Basis Unrealized Gains Unrealized Losses Fair Value (Thousands of dollars) Investments: Money market mutual funds $ 5,601 $ — $ — $ 5,601 U.S. government agencies 7,501 — (34 ) 7,467 Corporate bonds and notes 63,880 — (330 ) 63,550 Subtotal 76,982 — (364 ) 76,618 Deferred compensation plan assets included in other assets 2,685 — — 2,685 Total $ 79,667 $ — $ (364 ) $ 79,303 At December 31, 2018 and December 31, 2017 , we classified $19.8 million and $12.4 million , respectively of our aggregate investments as long-term investments and recorded them in our Condensed Consolidated Balance Sheets as restricted cash and investments, as they are securing outstanding letters of credit with maturities beyond one year. The following table presents the cost and fair value of our debt investments based on maturities as of December 31, 2018 2017 Amortized Costs Fair Value Amortized Costs Fair Value (Thousands of dollars) Due in one year or less $ — $ — $ 31,348 $ 31,254 Due within two years — — 40,032 39,763 Total $ — $ — $ 71,380 $ 71,017 The following table presents the average coupon rate percentage and the average days to maturity of our debt investments as of December 31, 2018 2017 Average Coupon Rate (%) Average Days To Maturity Average Coupon Rate (%) Average Days To Maturity U.S. government agencies — 0 1.370 370 Corporate bonds and notes — 0 1.766 392 The following table presents the fair value and unrealized losses related to our investments that have been in a continuous unrealized loss position for less than twelve months as of December 31, 2018 2017 Fair Value Unrealized Losses Fair Value Unrealized Losses (Thousands of dollars) U.S. government agencies $ — $ — $ 5,472 $ (28 ) Corporate bonds and notes — — 44,069 (271 ) Total $ — $ — $ 49,541 $ (299 ) The following table presents the fair value and unrealized losses related to our investments that have been in a continuous unrealized loss position for twelve months or more as of December 31, 2018 2017 Fair Value Unrealized Losses Fair Value Unrealized Losses (Thousands of dollars) U.S. government agencies $ — $ — $ 1,994 $ (6 ) Corporate bonds and notes — — 19,482 (59 ) Total $ — $ — $ 21,476 $ (65 ) From time to time over the periods covered in our financial statements included herein (an as illustrated in the forgoing tables), our investments have experience net unrealizable losses. We consider these declines in market value to be due to customary market fluctuations, and we typically do not plan to sell these investments prior to maturity. For these reasons, we do not considered any of our investments to be other than temporarily impaired at December 31, 2017. For additional information regarding our criteria for making these assessments, see Note 3 to the financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2017.

Fair Value

Fair Value	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value	FAIR VALUE Accounting guidance defines fair value as the price that would be received to sell an asset or transfer a liability in an orderly transaction between market participants at the measurement date. This guidance establishes a hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available. The hierarchy for inputs is categorized into three levels based on the reliability of inputs as follows: Level 1: Quoted market prices in active markets for identical assets or liabilities. Level 2: Observable market based inputs or unobservable inputs that are corroborated by market data. Level 3: Unobservable inputs that are not corroborated by market data. The following tables summarize the valuation of our investments and financial instruments by the above pricing levels as of the valuation dates listed: December 31, 2018 Total (Level 1) (Level 2) (Thousands of dollars) Investments: Money market mutual funds $ 26,308 $ 26,308 $ — Deferred compensation plan assets 772 772 Total $ 27,080 $ 27,080 $ — December 31, 2017 Total (Level 1) (Level 2) (Thousands of dollars) Investments: Money market mutual funds $ 5,601 $ 5,601 $ — U.S. government agencies 7,467 — 7,467 Corporate bonds and notes 63,550 — 63,550 76,618 5,601 71,017 Deferred compensation plan assets 2,685 2,685 — Total $ 79,303 $ 8,286 $ 71,017 We hold our short-term investments in an investment fund consisting of high quality money market instruments of governmental and private issuers, which is classified as a short-term investment. Level 1 inputs are quoted prices (unadjusted) for identical assets or liabilities in active markets. These items are traded with sufficient frequency and volume to provide pricing on an ongoing basis. The fair values of the investments in these funds are based on observable market prices, and therefore, have been categorized in Level 1 in the fair value hierarchy. Level 2 inputs reflect quoted prices for identical assets or liabilities that are not actively traded. These items may not be traded daily; examples include commercial paper, corporate bonds and U.S. government agencies debt. There have been no reclassifications of assets between Level 1 and Level 2 investments during the periods covered by the financial statements included in this report. We hold no Level 3 investments. Investments reflected on our balance sheets as Other Assets, which we hold to fund liabilities under our Officers’ Deferred Compensation Plan, consist mainly of multiple investment funds that are highly liquid and diversified. Cash, accounts receivable, accounts payable and accrued liabilities, revolving credit facilities and related party term loan all had fair values approximating their carrying amounts at December 31, 2018 and 2017 . We determine the estimated fair value of our 5.25% Senior Notes due 2019 using Level 2 inputs, including quoted market indications of similar publicly-traded debt. The fair value of our 5.25% Senior Notes was $344.2 million at December 31, 2018.

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Property and Equipment	PROPERTY AND EQUIPMENT The following table summarizes the Company’s property and equipment at December 31 of the following years: 2018 2017 (Thousands of dollars) Flight equipment $ 1,227,341 $ 1,225,205 Facility & improvements 67,784 64,316 Operating equipment 30,832 29,913 Data processing equipment 35,889 34,747 Vehicles 3,798 8,202 Medical equipment 8,710 8,354 Other 6,056 6,523 1,380,410 1,377,260 Less accumulated depreciation and amortization (477,925 ) (430,495 ) Property and equipment, net $ 902,485 $ 946,765 Depreciation expense related to property and equipment was $56.8 million in 2018 , $50.6 million in 2017 , and $49.2 million in 2016 . These amounts are reported as Direct expenses and Selling, general, and administrative expenses in our Consolidated Statements of Operations included elsewhere herein.

Other Assets

Other Assets	12 Months Ended
	Dec. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets	OTHER ASSETS The following table summarizes the Company’s other assets at December 31 of the following years: 2018 2017 (Thousands of dollars) Deposits on future purchases of aircraft $ 501 $ 501 Investment in Variable Interest Entities 519 330 Investments (Officers’ Deferred Compensation Plan) 772 2,685 Deferred Cost 2,721 — Receivables / Deposits Long Term 12,187 4,875 Other 1,678 350 Total $ 18,378 $ 8,741

Accrued and Other Current Liabi

Accrued and Other Current Liabilities	12 Months Ended
	Dec. 31, 2018
Payables and Accruals [Abstract]
Accrued and Other Current Liabilities	ACCRUED AND OTHER CURRENT LIABILITIES Accrued and other current liabilities as of December 31 consisted of the following: 2018 2017 (Thousands of dollars) Salaries & wages $ 9,130 $ 6,240 Incentive compensation 5,226 8,991 Income taxes 895 930 Interest 7,774 8,108 Vacation payable 8,838 7,619 Group medical 1,755 1,344 Transportations tax 301 971 Operating lease 658 710 Workers compensation 846 959 Other 9,869 5,978 Total accrued liabilities $ 45,292 $ 41,850

Debt

Debt	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt	T Listed below is information regarding our indebtedness. All indebtedness owed under our Senior Notes as of December 31, 2018 is classified as short-term debt on our balance sheet as of such date. December 31, 2018 December 31, 2017 Principal Unamortized Debt Issuance Debt Cost Principal Unamortized Debt Issuance Debt Cost (Thousands of dollars) Senior Notes issued March 17, 2014, interest only payable semi-annually at 5.25%, maturing March 15, 2019. $ 500,000 $ 260 $ 500,000 $ 1,506 Revolving Credit Facility due March 7, 2019 with a group of commercial banks, interest payable at variable rates. — — 117,500 — Related Party Loan - Thirty Two L.L.C., interest payable quarterly at 6%, due September 28, 2020. 130,000 765 — — Total long-term debt. $ 630,000 $ 1,025 $ 617,500 $ 1,506 Listed below is information on our future annual maturities of long-term debt (in thousands): 2019 $ 500,000 2020 130,000 2021 — 2022 — 2023 — Thereafter — Total $ 630,000 Senior Notes - Subject to the automatic stay of the Bankruptcy Code, our 5.25% Senior Notes (the “2019 Notes”) matured on March 15, 2019. These notes are unconditionally guaranteed on a senior basis by each of PHI, Inc.’s wholly-owned domestic subsidiaries. These notes and related guarantees are the general, unsecured obligations of PHI, Inc. and the guarantors. Interest is payable semi-annually on March 15 and September 15 of each year. PHI has the option to redeem some or all of the 2019 Notes at any time on or after March 15, 2018 at par plus accrued interest. The indenture governing the 2019 Notes (the “2019 Indenture”) contains, among other things, certain restrictive covenants, including limitations on incurring indebtedness, creating liens, selling assets and entering into certain transactions with affiliates. The covenants also limit PHI’s ability to, among other things, pay cash dividends on common stock, repurchase or redeem common or preferred equity, prepay subordinated debt and make certain investments. Related Party Term Loan - On September 28, 2018, we entered into a term loan agreement with Thirty Two L.L.C., which provided us with a term loan of $130 million maturing on September 28, 2020. This loan bears interest at an annual fixed rate of 6% payable quarterly, with all principal due on maturity. Thirty Two L.L.C., an entity wholly-owned by our CEO and controlling shareholder, is a related party. Contemporaneously with borrowing $130.0 million under the term loan, we applied approximately $122.7 million of the loan proceeds to repay principal and accrued interest under our senior secured revolving credit facility, which was terminated in connection with such repayment, and applied the remainder of the proceeds to cash collateralize certain outstanding letters of credit. Obligations under the term loan are guaranteed by PHI Air Medical, L.L.C. and PHI Tech Services, Inc., both of which are wholly-owned by us. Our obligations and the guarantors’ obligations are secured by all of their respective inventory and accounts receivable located in the U.S., as well as certain spare parts. The term loan agreement contains customary restrictive covenants that, subject to certain exceptions and limitations, limit or restrict our ability to, among other things, (i) purchase, retire or redeem any shares of our capital stock; (ii) incur indebtedness; (iii) mortgage or encumber our assets; (iv) make loans to, or guarantee the indebtedness of, any individual or entity; (v) effect a change of control of PHI; (vi) consolidate with or merge into any other corporation, or permit any other corporation to merge into us; (vii) sell or lease all or substantially all of our assets; or (viii) acquire all or a substantial part of the assets or capital stock of another entity. The term loan agreement contains no financial covenants. The term loan agreement contains customary representations and warranties, affirmative covenants and events of default. Letter of Credit - At December 31, 2018 , we had $19.8 million of outstanding letters of credit secured by a like amount of restricted cash and investments, $12.1 million of which secured certain domestic operations or insurance policies and $7.7 million of which guaranteed our performance under an international contract. At December 31, 2017, we had $19.6 million of outstanding letters of credit issued for the same purposes. Other - PHI, Inc. has cash management arrangements with certain of its principal subsidiaries, in which substantial portions of the subsidiaries’ cash is regularly advanced to PHI, Inc. Although PHI, Inc. periodically repays these advances to fund the subsidiaries’ cash requirements throughout the year, at any given point in time PHI, Inc. may owe a substantial sum to its subsidiaries under these advances, which, in accordance with GAAP, are eliminated in consolidation and therefore not recognized on our consolidated balance sheets. For additional information, see Note 17. Subsequent Event - New Term Loan Agreement - On March 13, 2019, we entered into a Loan Agreement, dated the same date (the “Term Loan Agreement”), by and among the Company, as borrower, certain of our subsidiaries as guarantors party thereto, the lenders from time to time party thereto, and Blue Torch Finance, LLC, as administrative agent and collateral agent, for a first lien term loan of up to $70 million (the “Term Loan”). Immediately upon entering into the Term Loan Agreement, and prior to the filing of the Chapter 11 Cases, we borrowed $70 million thereunder, the net proceeds of which (after the payment of transaction expenses and fees thereunder) are expected to be used to fund the working capital and liquidity requirements of the Company during the pendency of the Chapter 11 Cases and thereafter. For additional information regarding our Chapter 11 Cases, see Notes 1 and 19. The full principal amount of the Term Loan is due March 13, 2023. At our election, borrowings under the Term Loan will bear interest at either (x) the LIBOR Rate (as defined in the Term Loan Agreement) plus 6% or (y) the Base Rate (as defined in the Term Loan Agreement) plus 5% . The Term Loan is secured by a first lien on 91 aircraft registered and located in Antarctica, Australia, Canada, and the United States (which are currently deployed primarily in our oil and gas and technical services operations), the related spare parts for such aircraft, and certain other non-working capital assets, as well as a second lien on all working capital assets (second in priority to the liens granted under our above-described term loan agreement, dated as of September 28, 2018, with Thirty Two, L.L.C.). The Term Loan Agreement contains customary pre-payment requirements. In addition, we have paid a funding fee, which is subject to forgiveness based on certain future events. The Term Loan Agreement contains certain customary negative covenants that, among other things, restrict, subject to certain exceptions, the Company’s and each guarantor’s incurrence of additional indebtedness or liens, mergers, dispositions of assets, investments, restricted payments, modifications to material agreements, sale and leasebacks, transactions with affiliates, fundamental changes, locations of certain aircraft and acquisitions of assets. In addition, the financial covenants under the Term Loan Agreement require us to maintain (a) minimum liquidity of the Company, the guarantors and their respective subsidiaries, as of the last day of any calendar month, of at least $20 million of unrestricted cash and cash equivalents (provided that at least $10 million of such cash and cash equivalents shall, as of any date of determination, be held solely by the Company and the guarantors); (b) a minimum fixed charge coverage ratio, as of the last day of the following test periods, commencing with the first full fiscal quarter following the effective date of the plan of reorganization in the Chapter 11 Cases, of at least (i) 0.0000 :1.00 for quarters ending on or prior to March 31, 2020, (ii) 0.1875 :1.00 for quarters ending from June 30, 2020 through September 30, 2020, (iii) 0.3750 :1.00 for quarters ending from December 31, 2020 through March 31, 2021, (iv) 0.9125 :1.00 for quarters ending from June 30, 2021 through September 30, 2021, and (v) 1.2000 :1.00 for quarters ending on December 31, 2021 and thereafter; (c) a secured leverage ratio, as of the last day of each of the following test periods, commencing with the first full fiscal quarter ending following the effective date of the plan of reorganization in the Chapter 11 Cases (as defined below), of no greater than (i) 4.50 :1.00 on or prior to September 30, 2020, (ii) 4.25 :1.00 from December 31, 2020 through September 30, 2021, (iii) 4.00 :1.00 from December 31, 2021 through December 30, 2022 and (iv) 3.75 :1.00 on December 31, 2022 and thereafter; and (d) a total appraisal ratio of the aircraft collateral (less dispositions permitted under the Term Loan Agreement) to borrowings outstanding under the Term Loan, as of the last day of any calendar month, of at least 4.00 :1.00. The Term Loan Agreement also contains customary affirmative covenants and customary representations and warranties. The Term Loan Agreement specifies certain customary events of default, including, among others, failure to pay principal or interest on the Term Loan when due, the breach of representations or warranties in any material respect, non-performance of other covenants and obligations, judgments in excess of $2.5 million , the occurrence of certain ERISA events resulting in liability in excess of $2.5 million , impairments of more than $2.5 million of the collateral securing the Term Loan, and certain change of control events. The filings of the Chapter 11 Cases neither constitute an event of default nor accelerate payment of the Company’s indebtedness under the Term Loan Agreement. Subsequent Events - Acceleration of Certain Debt Obligations - The commencement of the Chapter 11 Cases constituted an event of default that accelerated the obligations under the indenture governing our 5.25% Senior Notes due 2019 and our term loan agreement with Thirty Two, L.L.C. Any efforts to enforce payment of such financial obligations under such instruments and agreements are automatically stayed as a result of the filing of the Chapter 11 Cases and the holders’ rights of enforcement in respect of such financial obligations are subject to the applicable provisions of the Bankruptcy Code.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES For financial reporting purposes, (loss) earnings before income taxes includes the following components: Year Ended December 31, 2018 2017 2016 (Thousands of dollars) United States $ (95,590 ) $ (50,871 ) $ (25,604 ) Foreign (71,870 ) (570 ) (1,546 ) Total (167,460 ) (51,441 ) (27,149 ) The provision for income taxes for 2018, 2017, and 2016 consisted of the following: Year Ended December 31, 2018 2017 2016 (Thousands of dollars) U.S. Federal: Current $ — $ — $ — Deferred (21,061 ) (57,637 ) (5,488 ) (21,061 ) (57,637 ) (5,488 ) U.S. State: Current $ 392 $ 199 $ 427 Deferred $ (2,058 ) $ (717 ) $ 3,218 $ (1,666 ) $ (518 ) $ 3,645 Foreign: Current $ 2,371 $ 108 $ 1,374 Deferred $ (5,590 ) (926 ) — $ (3,219 ) $ (818 ) $ 1,374 Provision for income taxes $ (25,946 ) $ (58,973 ) $ (469 ) Income tax expense as a percentage of pre-tax earnings varies from the effective Federal statutory rate of 21% as a result of the following: Year Ended Year Ended Year Ended (Thousands of dollars, except percentage amounts) Amount Tax Amount Tax Amount Tax Income taxes at statutory rate $ (35,167 ) 21.0 % $ (18,004 ) 35.0 % $ (9,502 ) 35.0 % Increase (decrease) in taxes resulting from: Valuation allowance on foreign tax credits 229 -0.1 % 6,145 -12.0 % 8,991 -33.0 % Valuation allowance on state net operating loss carryforwards 107 -0.1 % 868 -2.0 % 5,028 -19.0 % Valuation Allowance - Other 88 -0.1 % 1,353 -3.0 % — — % Goodwill impairment 17,729 -10.6 % — — % — — % Change in tax rate on deferred items (1,163 ) 0.7 % — — % (4,772 ) 18.0 % Tax reform – Impact of change in tax rate — — % (49,219 ) 96.0 % — — % State income taxes, net of federal benefit (1,774 ) 1.1 % (1,386 ) 3.0 % (1,384 ) 5.0 % Foreign income tax rate differential (6,245 ) 3.7 % Other items – net 250 -0.1 % 1,270 -2.0 % 1,170 -4.0 % Total $ (25,946 ) 15.5 % $ (58,973 ) 115.0 % $ (469 ) 2.0 % On December 22, 2017, the Tax Cuts and Jobs Act (the “Act”) was enacted which significantly reformed the U.S. Internal Revenue Code (the “Code”). The Act, among other things, reduced the federal corporate income tax rate from 35% to 21% effective January 1, 2018. The change in the federal tax rate required us under applicable accounting rules to remeasure our deferred tax assets and liabilities, and to recognize the impact of this remeasurement in the period of enactment of the rate change. As a result, we provisionally recognized a net benefit of $49.2 million in our consolidated statement of operations for the year ended December 31, 2017. Pursuant to the Act, the SEC staff issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act (SAB 118), which allowed us to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. As a result, we previously provided a provisional estimate of the effect of the Act in our consolidated financial statements. In the fourth quarter of 2018, we completed our analysis to determine the effect of the Act and recorded immaterial adjustments as of December 31, 2018. In 2018 and 2016, the change in tax rate on deferred items is mainly related to increases or reductions in the estimated effective tax rate that will be present at the time the deferred tax assets and liabilities reverse for tax purposes. The decrease in 2018 is attributable to a change in composition of earnings in the various jurisdictions in which we operate. The decrease in 2016 is attributable to a decline in the apportionment percentages in the various jurisdictions in which we operate, primarily as a result of a change in law related to apportionment factor calculations in one jurisdiction and a change in the composition of earnings in the various jurisdictions in which we operate. In 2018 and 2016, the overall impact of state apportionment percentage changes was a tax benefit of $1.2 million and $4.8 million , respectively. In 2017, the impact of state apportionment changes are included within the overall provisional net benefit described above. In fiscal year 2018, the Company recognized tax expense of $17.7 million related to the impairment of Goodwill discussed in Note 18. Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The tax effects of significant items comprising our net deferred tax balance at December 31 are as follows: 2018 2017 (Thousands of dollars) Deferred tax assets: Deferred compensation $ 162 $ 626 Foreign tax credits 18,826 19,453 Vacation and bonus accrual 2,170 3,936 Inventory valuation 6,686 4,954 Interest disallowance 5,497 — Rental accrual 601 747 Hurricane relief credit 1,308 1,255 Stock-based compensation 2,118 988 Other 2,653 2,235 Net operating losses 95,307 82,044 Total deferred tax assets 135,328 116,238 Valuation allowance – state NOL carryforwards (6,105 ) (5,998 ) Valuation allowance – tax credit carryforwards (16,127 ) (16,537 ) Valuation allowance – foreign NOL carryforwards (186 ) (98 ) Total deferred tax assets, net 112,910 93,605 Deferred tax liabilities: Tax depreciation in excess of book depreciation (165,193 ) (171,116 ) Other (1,951 ) (5,185 ) Total deferred tax liabilities (167,144 ) (176,301 ) Net deferred tax liabilities $ (54,234 ) $ (82,696 ) Deferred tax assets – short-term — — Deferred tax assets – long-term 4,944 3,309 Deferred tax liability – long-term (59,178 ) (86,005 ) Net deferred tax liabilities $ (54,234 ) $ (82,696 ) The Company has U.S. Federal net operating loss carryforwards (“NOLs”) of approximately $352.4 million that, if not used, will expire beginning in 2028 through 2038 . Additionally, for state income tax purposes, the Company has NOLs of approximately $264.6 million available to reduce future state taxable income. These NOLs expire in varying amounts through 2038 , the majority of which expire in 2024 through 2038 . The Company had a valuation allowance of $6.1 million as of December 31, 2018 against certain net operating losses in six states which we have determined are more likely than not to be forfeited in future years. During 2018 , the Company recorded $0.1 million of valuation allowances on state NOLs. The Company’s deferred income tax balance as of December 31, 2018 includes deferred tax balances related to foreign entities that were acquired by the Company pursuant to the purchase of the HNZ Group Inc.’s offshore business on December 29, 2017. As of December 31, 2018, the Company has $3.6 million of net deferred tax assets related to its acquired Australian operation and $0.6 million of net deferred tax liabilities related to its acquired New Zealand operation. The net deferred tax assets related to Australia is mainly comprised of net operating losses of approximately $15.2 million that, if not used, can be carried forward indefinitely. The Company also has foreign tax credits of approximately $18.8 million and general business credits of approximately $1.3 million which expire at various dates through 2028. The estimated future U.S. taxable income, after utilization of the available net operating loss carryforwards, will limit the ability of the Company to utilize some of the foreign tax credit carryforwards during their carry forward period and it is not more likely than not that a portion of these credits will be utilized in future years. Therefore, the Company has a valuation allowance of $16.1 million on these credits, $0.2 million of which was recorded in 2018 . The increase in the valuation allowance is attributable to a change in estimate where it has been determined that the tax credits will expire before being fully utilized. The Company files income tax returns in the U.S. federal jurisdiction and in many U.S. state jurisdictions. The tax years 2015 to 2018 remain open to examination by the major taxing jurisdictions in which the Company is subject to tax. Income taxes paid were approximately $2.3 million , $1.2 million , and $2.6 million for each of the years ended December 31, 2018 , 2017 , and 2016, respectively. At December 31, 2018 , the Company had no unrecognized tax benefits. It is the Company’s practice to recognize interest and penalties related to income tax expense as part of non-operating expenses.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE The components of basic and diluted earnings per share for the years ended December 31, are as follows: 2018 2017 2016 (in thousands) Weighted average outstanding shares of common stock, basic 15,818 15,762 15,663 Dilutive effect of unvested restricted stock units — — — Weighted average outstanding shares of common stock, diluted 15,818 15,762 15,663 For the years ended December 31, 2018 and December 31, 2017, there were no unvested restricted stock units excluded from the weighted average outstanding shares of common stock, diluted. There were 24,468 shares of stock that were anti-dilutive to earnings for the year ended December 31, 2016.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2018
Postemployment Benefits [Abstract]
Employee Benefit Plans	EMPLOYEE BENEFIT PLANS Deferred Compensation Plan The Company maintains an Officer Deferred Compensation Plan that permits key officers to defer a portion of their compensation. The plan is nonqualified and we are not obligated to fund it. The Company has established a separate bookkeeping account for each participant, which is treated as if invested and reinvested from time to time in investments that the participant selects from a list of available investment choices. These accruals are periodically adjusted for gains and losses to reflect the performance of the hypothetical investments. Earnings and losses on the book reserve accounts accrue to the plan participants. Liabilities for the plan are included in other long-term liabilities, and the corresponding investment accounts funded by voluntary contributions are included in other assets. Aggregate amounts deferred under the plans were $0.8 million and $2.7 million for the years ended December 31, 2018 and 2017 , respectively. Incentive Compensation The Company has one incentive compensation plan. The incentive compensation plan for non-executive employees allows the Company to pay up to 3.0% of the employee's annual earnings upon achieving a specified earnings threshold. The Company also has an executive/senior management plan for certain corporate and business unit management employees. Under this plan, the bonus is a percentage of each participating employee’s base salary based upon the each segment’s achievement of the financial target established by the Board of Directors at three levels – a threshold level, a target level, and a stretch level, subject to a positive or negative adjustment for the Company’s safety performance. Pursuant to these plans, the Company incentive compensation expense for the years ended December 31, 2018 , 2017 , and 2016 were $5.7 million , $9.0 million , and $1.6 million , respectively. We also have a Safety Incentive Plan related to Occupational Safety and Health Administration recordable incidents, for which we expensed and paid $0.7 million , $0.6 million , and $0.9 million for the years 2018 , 2017 , and 2016 , respectively. 401(k) Plan We sponsor a 401(k) Plan (“Plan”) for our employees. An employee is eligible to participate in the Plan immediately upon employment and receive a dollar matching contribution up to 6% of his or her base compensation. The vesting for matching contributions is 25% per year beginning at the end of the second year of employment. Employees are fully vested after completing five years of service to the Company. The matching contribution for the years ended December 31, 2018 , 2017 , and 2016 were $10.0 million , $9.5 million , and $10.1 million , respectively.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	STOCK-BASED COMPENSATION Compensation expense for our stock-based plans was $6.1 million , $4.4 million , and $(0.1) million for 2018 , 2017 , and 2016 , respectively. 2012 Long-Term Incentive Plan – Under our Second Amended and Restated Long-Term Incentive Plan (“LTIP”), we are authorized to issue up to 3,500,000 shares of non-voting stock. As of December 31, 2018 , 1,149,175 shares remained available for grant. Time-vested restricted stock units granted under the LTIP generally have forfeiture restrictions that lapse 100% after three years. Performance-based restricted stock units that have been granted under the LTIP, whose vesting is contingent upon meeting company-wide performance goals, have forfeiture restrictions that lapse, at the end of a three-year performance period if all performance and continued service conditions are met. Non-Voting Time-Vested Restricted Stock Units – The following table summarizes the activity for non-voting time-vested restricted stock units granted to employees for the year ended December 31, 2018 . Share Units Weighted Average Grant-Date Fair Value Remaining Average Contractual Life ( in years) Aggregate Value ( in thousands) Outstanding at January 1, 2018 534,711 $ 12.80 2.26 $ 6,844 Granted 366,055 12.55 Forfeited (6,755 ) 19.86 Vested and released to participants (28,723 ) 29.45 Outstanding at December 31, 2018 865,288 $ 11.73 1.88 $ 10,146 The weighted average grant-date fair value of time-vested restricted stock units granted during 2018 and 2017 was $12.55 and $11.42 per share, respectively. The total fair value of awards that vested in 2018 was $0.3 million . The total fair value of awards that vested in 2017 was $1.5 million . The total fair value of awards forfeited in 2018 was less than $0.1 million . The total fair value of awards forfeited in 2017 was $0.4 million . As of December 31, 2018 , there was $5.9 million that is expected to be recognized over a weighted average period of 1.88 years. The following table summarizes the activity for non-voting time-vested restricted stock units granted to non-employee directors for the year ended December 31, 2018 . Share Units Weighted Average Grant-Date Fair Value Remaining Average Contractual Life (in years) Aggregate Value (in thousands) Outstanding at January 1, 2018 19,680 $ 14.94 2.71 $ 292 Granted 15,225 8.77 Forfeited — — Vested and released to participants (4,452 ) 21.42 Outstanding at December 31, 2018 30,453 $ 10.99 2.19 $ 335 Non-Voting Performance-Based Restricted Stock Units – The following table summarizes the activity for non-voting performance-based restricted stock units for the year ended December 31, 2018 . Share Units Weighted Average Grant-Date Fair Value Remaining Average Contractual Life ( in years) Aggregate Value ( in thousands) Outstanding at January 1, 2018 818,150 $ 18.60 1.20 $ 15,218 Granted 448,012 12.54 Forfeited (165,397 ) 31.33 Vested and released to participants — — Outstanding at December 31, 2018 1,100,765 $ 13.23 1.99 $ 14,564 The aggregate value of the awards in the above table reflects the impact of current expectations of achievement through the end of the performance cycle. The average grant-date fair value of performance based restricted stock units granted during 2018 was $12.54 per share. The total fair value of awards that vested in 2018 was $0 . Total fair value of awards forfeited in 2018 was $2.1 million . As of December 31, 2018 , there was a total of $4.9 million of unrecognized compensation cost related to the non-vested performance-based restricted stock units. Subsequent Event – On February 20, 2019 the PHI Compensation committee approved the vesting of the 2017 performance RSUs based on the company’s financial results and exceeding the pre-determined business performance metrics set in 2017 for the two year performance period (January 1, 2017 - December 31, 2018). The PHI compensation committee also agreed to settle these RSU award vesting in cash effective at the closing market price on February 20, 2019 which was $2.21 . This represents a modification of these awards. The total amount paid was $0.8 million .

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Operating Leases The Company leases certain aircraft, facilities, and equipment used in its operations. The related lease agreements, which include both non-cancelable and month-to-month terms, generally provide for fixed monthly rentals and, for certain real estate leases, renewal options. The Company generally pays all insurance, taxes, and maintenance expenses associated with these aircraft leases and some of these leases contain renewal and purchase options at fair market values. Rental expense incurred under these leases consisted of the following: Year Ended Year Ended Year Ended (Thousands of dollars) Aircraft $ 35,740 $ 39,815 $ 44,130 Other 11,718 9,504 9,451 Total $ 47,458 $ 49,319 $ 53,581 The following table presents the remaining aggregate lease commitments under operating leases having initial non-cancelable terms in excess of one year as of December 31, 2018. The table includes renewal periods on the principal operating facility lease. Aircraft Other Total (Thousands of dollars) 2019 $ 29,705 $ 6,765 $ 36,470 2020 27,406 5,403 32,809 2021 27,272 3,855 31,127 2022 26,758 2,018 28,776 2023 19,170 516 19,686 Thereafter 9,907 761 10,668 $ 140,218 $ 19,318 $ 159,536 A majority of our aircraft operating leases contain financial covenants that are substantially similar to the financial covenants that were contained in our revolving credit facility at the time the leases were entered into. We have solicited and received amendments and waivers of certain covenants in some of these leases. We remain in active discussions with our aircraft lessors to resolve open issues and pursue any additional waivers or amendments that may be required, but cannot assure you that these efforts will be successful. Furthermore the aircraft operating leases may be impacted by our Chapter 11 Cases. For additional information regarding our Chapter 11 Cases see Notes 1 and 19. Generally in the event of a default, the applicable lessor has the option of terminating the lease and requiring the return of the leased aircraft, with the repayment of any arrears of lease payments plus additional damages which may include the present value of all future lease payments and certain other amounts which could be material to our financial position. Purchase Options As of December 31, 2018 , we had options to purchase aircraft under lease becoming exercisable in 2019 through 2020. The aggregate option purchase prices are, $129.0 million in 2019, and $22.7 million in 2020. Under current conditions, we believe that it is unlikely that we will exercise the 2019 purchase options. Whether we exercise the remaining options will depend upon several factors, including market conditions and our available cash at the respective exercise dates. Guarantees In the normal course of business with customers, vendors, and others, we provide guarantees, performance, and payment bonds pursuant to certain agreements. The aggregate amount of these guarantees and bonds at December 31, 2018 was $1.0 million . Environmental Matters PHI has recorded an estimated liability of $0.15 million as of December 31, 2018 for environmental response costs. Previously, PHI conducted environmental surveys of its former Lafayette Facility located at the Lafayette Regional Airport, which former facility PHI vacated in 2001, and determined that limited soil and groundwater contamination exist at two parcels of land at the former facility. An Assessment Report for both parcels was submitted in 2003 (and updated in 2006) to the Louisiana Department of Environmental Quality (LDEQ) and the Louisiana Department of Natural Resources (LDNR). Approvals for the Assessment Report were received from the LDEQ and LDNR in 2010 and 2011, respectively. Since that time, PHI has performed groundwater sampling of the required groundwater monitor well installations at both former PHI facility parcels and submitted these sampling reports to the LDEQ. Pursuant to an agreement with the LDEQ, PHI provided groundwater sample results semi-annually to the LDEQ for both former PHI facility parcels from 2005 to 2015. LDEQ approved a reduction in the sampling program from semi-annual to annual groundwater monitoring in 2015. Based on PHI’s working relationship and agreements with the LDEQ, and the results of ongoing former facility parcel monitoring, PHI believes that ultimate remediation costs for the subject parcels will not be material to PHI’s consolidated financial position, operations or cash flows. Legal Matters On September 25, 2017, we brought a suit in the U.S. District Court for the Western District of Louisiana against Office & Professional Employees International Union and Office & Professional Employees International Union, Local 108 (Civil Action No. 6:17 cv 01216), which collectively represent our domestic pilot workforce. In this suit, we sought declaratory relief and other remedies under federal law to confirm that we could increase the wages of most of our unionized pilots and provide enhanced benefits of employment without negotiating these proposed changes with the defendants. On February 20, 2018, we dismissed our suit without prejudice in connection with the defendants' withdrawal of their prior demand to negotiate these charges. On March 14, 2019 (the “Petition Date”), the Company and its four principal U.S. subsidiaries listed on Exhibit 99.1 hereto (collectively, the “Debtors”) filed voluntary petitions (the “Chapter 11 Cases”) in the United States Bankruptcy Court for the Northern District of Texas (the “Bankruptcy Court”) seeking relief under Chapter 11 of Title 11 of the United States Code (the “Bankruptcy Code”). The Debtors have requested joint administration of their Chapter 11 Cases under the caption In re: PHI, Inc., et al., Case N0. 19-30923. The Debtors continue to operate their businesses and manage their properties as “debtors-in-possession” under the jurisdiction of the Bankruptcy Court and in accordance with the applicable provisions of the Bankruptcy Code and orders of the Bankruptcy Court. To ensure their ability to continue operating in the ordinary course of business, the Debtors have filed with the Bankruptcy Court motions seeking a variety of “first-day” relief, including authority to pay employee wages and benefits, honor customer programs, and pay utilities providers, insurance providers and other vendors and suppliers in the ordinary course for all goods and services provided after the Petition Date. From time to time, we are involved in various legal actions incidental to our business, including actions relating to employee claims, actions relating to medical malpractice claims, various tax issues, grievance hearings before labor regulatory agencies, and miscellaneous third party tort actions. The outcome of these proceedings is not predictable. However, based on current circumstances, we do not believe that the ultimate resolution of these proceedings, after considering available defenses and any insurance coverage or indemnification rights, will have a material adverse effect on our financial position, results of operations or cash flows.

Business Segments and Geographi

Business Segments and Geographic Areas	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Business Segments and Geographic Areas	BUSINESS SEGMENTS AND GEOGRAPHIC AREAS Under Accounting Standards Codification 280, “Segment Reporting,” we have determined that we have the following three reportable segments: • Oil and Gas • Air Medical • Technical Services. A segment’s operating profit or loss is its operating revenues less its direct expenses and selling, general and administrative expenses. Each segment has a portion of selling, general and administrative expenses that is charged directly to the segment and a portion that is allocated. Direct charges represent the vast majority of segment selling, general and administrative expenses. Allocated selling, general and administrative expenses is based primarily on total segment costs as a percentage of total operating costs. In addition, a portion of our selling, general and administrative expenses are not allocated to any segment. The Oil and Gas segment provides helicopter services to oil and gas customers operating in the Gulf of Mexico and a selected number of foreign countries. The Air Medical segment provides helicopter services to hospitals and emergency service providers in several U.S. states, and individuals, in which case the Company is paid by either a commercial insurance company, federal or state agency, or the patient. The Technical Services segment provides helicopter repair and overhaul services for existing flight operations customers that own their own aircraft. Under this segment, the Company periodically provides certain services to governmental customers, including the Company’s agreement to operate six aircraft for the National Science Foundation in Antarctica. Under this segment, we also offer certain software as a service to our Oil and Gas customers. Air Medical operations are headquartered in Phoenix, Arizona, where the Company maintains significant separate facilities and administrative staff dedicated to this segment. Those costs are charged directly to the Air Medical segment, resulting in a disproportionate share of selling, general and administrative expenses compared to the Company’s other reportable segments. The customers, individually or considered as a group under common ownership, which accounted for greater than 10% of accounts receivable or 10% of operating revenues during the periods reflected were as follows: Accounts Receivable December 31, Operating Revenues Years Ended December 31, 2018 2017 2018 2017 2016 Oil and Gas segment: Customer A 15 % 11 % 17 % 14 % 14 % Customer B 5 % 5 % 7 % 9 % 10 % Air Medical & Technical Services segments: Customer C — % 10 % — % — % 5 % The following table shows information about the profit or loss and assets of each of the Company’s reportable segments for the years ended December 31, 2018 , 2017 , and 2016 . The information contains certain allocations, including allocations of depreciation, rents, insurance, and overhead expenses that the Company deems reasonable and appropriate for the evaluation of its results of operations. The Company does not allocate gains on dispositions of property and equipment, other income, interest expense, income taxes, and corporate selling, general, and administrative expenses to its segments. Where applicable, the tables present the unallocated amounts to reconcile the totals to the Company’s consolidated financial statements. Corporate assets are principally cash, short-term investments, other assets, and certain property and equipment. Year Ended December 31, 2018 2017 2016 (Thousands of dollars) Segment operating revenues Oil and Gas $ 380,238 $ 298,398 $ 324,129 Air Medical 257,132 257,273 281,868 Technical Services 37,053 23,874 28,101 Total operating revenues 674,423 579,545 634,098 Segment direct expenses Oil and Gas (1) 371,930 321,272 344,640 Air Medical 230,840 208,987 227,877 Technical Services 28,849 16,825 19,882 Total segment direct expenses 631,619 547,084 592,399 Segment selling, general and administrative expenses Oil and Gas 18,485 5,899 6,739 Air Medical 13,833 12,442 10,968 Technical Services 1,418 1,405 1,101 Total segment selling, general and administrative expenses 33,736 19,746 18,808 Total segment expenses 665,355 566,830 611,207 Net segment (loss) profit Oil and Gas (10,177 ) (28,773 ) (27,250 ) Air Medical 12,459 35,844 43,023 Technical Services 6,786 5,644 7,118 Total net segment profit 9,068 12,715 22,891 Impairments of assets (109,024 ) (368 ) (407 ) Other, net (2) (574 ) 2,466 6,621 Unallocated selling, general and administrative expenses (32,949 ) (34,071 ) (25,610 ) Interest expense (33,981 ) (32,183 ) (30,644 ) (Loss) earnings before income taxes $ (167,460 ) $ (51,441 ) $ (27,149 ) (1) Includes equity in gain/loss of unconsolidated affiliate. (2) Includes gain/loss on disposition of property and equipment and other income. Year Ended December 31, 2018 2017 2016 (Thousands of dollars) Expenditures for Long-Lived Assets Oil and Gas $ 34,171 $ 52,525 $ 59,278 Air Medical 7,268 5,696 22,429 Corporate 1,469 257 1,164 Total $ 42,908 $ 58,478 $ 82,871 As of or for Year Ended December 31, 2018 2017 2016 (Thousands of dollars) Depreciation and Amortization Oil and Gas $ 47,723 $ 39,655 $ 40,170 Air Medical 22,606 20,413 19,716 Technical Services 499 581 564 Corporate 8,426 7,378 5,293 Total 79,254 68,027 65,743 Assets Oil and Gas $ 594,331 $ 722,734 Air Medical 387,701 372,646 Technical Services 5,515 5,979 Corporate 274,679 300,487 Total 1,262,226 1,401,846 The following table presents the Company’s revenues from external customers attributed to operations in the United States and foreign areas and long-lived assets in the United States and foreign areas. As of or for Year Ended December 31, 2018 2017 2016 (Thousands of dollars) Operating Revenues: United States $ 516,717 $ 530,115 $ 579,300 International 157,706 49,430 54,798 Total $ 674,423 $ 579,545 $ 634,098 Long-Lived Assets: United States $ 552,350 $ 601,530 International 350,135 345,235 Total $ 902,485 $ 946,765 Certain of those foreign customers pay us less promptly and regularly than our domestic customers. To date, these payment delays and irregularities have not resulted in any material losses. Nonetheless, these payment delays and irregularities have, among other things, disrupted our cash flows and exposed us to greater risks of non-payment, and could in the future potentially have a material adverse effect upon our financial position, liquidity, business or results of operations.

Quarterly Financial Data (Unaud

Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data (Unaudited)	QUARTERLY FINANCIAL DATA (UNAUDITED) The condensed quarterly results of operations for the years ended December 31, 2018 and 2017 (in thousands of dollars, except per share data) were as follows: Quarter Ended March 31, June 30, September 30, December 31, 2018 2018 2018 2018 (Thousands of dollars, except per share data) Operating revenues, net $ 160,370 $ 169,243 $ 168,787 $ 176,023 (Loss) gain on disposition of assets, net 879 (171 ) — 45 (Loss) earnings before income taxes (21,473 ) (8,777 ) (14,062 ) (123,148 ) Net (loss) earnings (16,983 ) (7,093 ) (11,531 ) (105,907 ) Net (loss) earnings per share Basic (1.07 ) (0.45 ) (0.73 ) (6.70 ) Diluted (1.07 ) (0.45 ) (0.73 ) (6.70 ) Quarter Ended March 31, June 30, September 30, December 31, 2017 2017 2017 2017 (Thousands of dollars, except per share data) Operating revenues, net $ 134,618 $ 146,424 $ 150,167 $ 148,336 Gain (loss) on disposition of assets, net — 7 4 287 Earnings before income taxes (23,073 ) (3,150 ) (4,899 ) (20,319 ) Net earnings (15,248 ) (3,273 ) (3,277 ) 29,330 Net earnings per share Basic (0.97 ) (0.21 ) (0.21 ) 1.87 Diluted (0.97 ) (0.21 ) (0.21 ) 1.87

Variable Interest Entity

Variable Interest Entity	12 Months Ended
	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Investment in Variable Interest Entity and Other Investments and Affiliates	INVESTMENT IN VARIABLE INTEREST ENTITY AND OTHER INVESTMENTS AND AFFILIATES We account for our investment in certain international operations as variable interest entities, which is defined as an entity that either (a) has insufficient equity to permit the entity to finance its operations without additional subordinated financial support or (b) has equity investors who lack the characteristics of a controlling financial interest. We account for our investment in PHI Century Limited ("PHIC") as a variable interest entity, which is defined as an entity that either (a) has insufficient equity to permit the entity to finance its operations without additional subordinated financial support or (b) has equity investors who lack the characteristics of a controlling financial interest. As of December 31, 2018 , we had a 49% investment in the common stock of PHIC, a Ghanaian entity. We acquired our 49% interest on May 26, 2011 , PHIC’s date of incorporation. The purpose of PHIC is to provide oil and gas flight services in Ghana and the West African region. For the year ended December 31, 2018 we recorded a gain in equity of this unconsolidated affiliate of $0.2 million and in 2017 we recorded a loss of $1.0 million relative to our 49% equity ownership. We had $4.8 million and $4.0 million of trade receivables from PHIC as of December 31, 2018 and 2017, respectively. In 2018 we loaned PHIC $0.4 million for operating purposes. This loan balance is included in account receivable - other on our Condensed Consolidated Balance Sheet at December 31, 2018 . Our investment in the common stock of PHIC is included in Other Assets on our Condensed Consolidated Balance Sheets and was $0.5 million for December 31, 2018 and 2017.

Condensed Consolidating Financi

Condensed Consolidating Financial Information - Guarantor Subsidiaries	12 Months Ended
	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Condensed Consolidating Financial Information - Guarantor Subsidiaries	CONDENSED CONSOLIDATING FINANCIAL INFORMATION – GUARANTOR SUBSIDIARIES As discussed further in Note 8, on March 17, 2014, PHI, Inc. issued $500.0 million aggregate principal amount of 5.25% Senior Notes due 2019 that are fully and unconditionally guaranteed on a joint and several, senior basis by all of PHI, Inc.’s domestic subsidiaries. PHI, Inc. directly or indirectly owns 100% of all of its domestic subsidiaries. The supplemental condensed financial information on the following pages sets forth, on a consolidated basis, the balance sheet, statement of operations, statement of comprehensive income, and statement of cash flows information for PHI, Inc. (“Parent Company”) the guarantor subsidiaries and the non-guarantor subsidiaries, each under separate headings. The eliminating entries eliminate investments in subsidiaries, intercompany balances, and intercompany revenues and expenses. The condensed consolidating financial statements have been prepared on the same basis as the consolidated financial statements of PHI, Inc. The equity method is followed by the Parent Company within the financial information presented below. The transactions reflected in “Due to/from affiliates, net” in the following condensed consolidated statements of cash flows primarily consist of centralized cash management activities between PHI, Inc. and its subsidiaries, pursuant to which cash earned by the guarantor subsidiaries is regularly transferred to PHI, Inc. to be centrally managed. Because these balances are treated as short-term borrowings of the Parent Company, serve as a financing and cash management tool to meet our short-term operating needs, turn over quickly and are payable to the guarantor subsidiaries on demand, we present borrowings and repayments with our affiliates on a net basis within the condensed consolidating statement of cash flows. Net receivables from our affiliates are considered advances and net payables to our affiliates are considered borrowings, and both changes are presented as financing activities in the following condensed consolidating statements of cash flows. Subsequent to the issuance of the Company's 2017 financial statements, the Company's management identified misstatements in the condensed consolidating balance sheet as of December 31, 2017, primarily related to consolidating eliminations for Non-Guarantor Subsidiaries. Investment in subsidiaries and others, other assets, and common stock and paid-in capital of the Parent Company and Non-Guarantor Subsidiaries, and the related Eliminations, have been restated to reflect the corrected amounts. The corrections increased investment in subsidiaries and others and decreased other assets in the Parent Company, increased other assets and common stock and paid-in capital in the Non-Guarantor Subsidiaries, and increased eliminations for investment in subsidiaries and others and common stock and paid-in capital by $131.9 million as compared to the previously reported amounts. These misstatements had no impact on our consolidated financial statements. The Company evaluated the materiality of these misstatements from quantitative and qualitative perspectives and concluded that they were immaterial to the prior period financial statements. PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS (Thousands of dollars) December 31, 2018 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated ASSETS Current Assets: Cash $ 39,091 $ 1,259 $ 10,524 $ — $ 50,874 Short-term investments 14,232 — — — 14,232 Accounts receivable – net 64,416 93,060 28,812 (3,823 ) 182,465 Intercompany receivable — 91,468 — (91,468 ) — Inventories of spare parts – net 43,933 9,577 3,188 — 56,698 Prepaid expenses 7,295 2,520 1,604 — 11,419 Deferred income taxes — — — — — Income taxes receivable 394 556 — — 950 Total current assets 169,361 198,440 44,128 (95,291 ) 316,638 Investment in subsidiaries and others 471,790 — — (471,790 ) — Property and equipment – net 576,763 287,375 38,347 — 902,485 Restricted cash and investments 19,781 — — — 19,781 Other assets 17,179 1,199 — — $ 18,378 Deferred income tax — — 4,944 — 4,944 Total assets $ 1,254,874 $ 487,014 $ 87,419 $ (567,081 ) $ 1,262,226 LIABILITIES AND SHAREHOLDERS’ EQUITY Current Liabilities: Senior Notes issued March 17, 2014 $ 499,740 $ — $ — $ — $ 499,740 Accounts payable $ 44,089 $ 4,587 $ 5,452 $ (3,839 ) $ 50,289 Accrued and other current liabilities 25,158 12,335 7,799 — 45,292 Intercompany payable 74,336 — 17,116 (91,452 ) — Total current liabilities 643,323 16,922 30,367 (95,291 ) 595,321 Long-term debt 129,235 — — — 129,235 Deferred income taxes and other long-term liabilities 4,934 58,752 551 — 64,237 Shareholders’ Equity: Common stock and paid-in capital 315,898 77,951 132,650 (210,601 ) 315,898 Accumulated other comprehensive loss (3 ) — (3,949 ) — (3,952 ) Retained earnings 161,487 333,389 (72,200 ) (261,189 ) 161,487 Total shareholders’ equity 477,382 411,340 56,501 (471,790 ) 473,433 Total liabilities and shareholders’ equity $ 1,254,874 $ 487,014 $ 87,419 $ (567,081 ) $ 1,262,226 PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS (Thousands of dollars) December 31, 2017 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated ASSETS Current Assets: Cash $ 47 $ 1,072 $ 7,651 $ — $ 8,770 Short-term investments 64,237 — — — 64,237 Accounts receivable – net 90,077 74,886 38,020 (17,004 ) 185,979 Intercompany receivable — 126,366 — (126,366 ) — Inventories of spare parts – net 68,737 9,049 3,095 — 80,881 Prepaid expenses 8,348 1,898 1,229 — 11,475 Deferred income taxes — — — — — Income taxes receivable 345 9 917 — 1,271 Total current assets 231,791 213,280 50,912 (143,370 ) 352,613 Investment in subsidiaries 529,222 — — (529,222 ) — Property and equipment – net 617,488 284,984 44,293 — 946,765 Restricted investments 12,382 — 14 — 12,396 Other assets 7,833 908 — — 8,741 Deferred income tax — — 3,309 — 3,309 Goodwill — — 61,299 — 61,299 Intangible assets — — 16,723 — 16,723 Total assets $ 1,398,716 $ 499,172 $ 176,550 $ (672,592 ) $ 1,401,846 LIABILITIES AND SHAREHOLDERS’ EQUITY Current Liabilities: Accounts payable $ 28,130 $ 4,636 $ 21,425 $ (17,005 ) $ 37,186 Accrued liabilities 23,147 10,577 8,126 — 41,850 Intercompany payable 113,387 — 12,978 (126,365 ) — Total current liabilities 164,664 15,213 42,529 (143,370 ) 79,036 Long-term debt 615,994 — — — 615,994 Deferred income taxes and other long-term liabilities 5,404 84,300 4,458 — 94,162 Shareholders’ Equity: Common stock and paid-in capital 309,933 77,951 133,296 (211,247 ) 309,933 Accumulated other comprehensive loss (280 ) — — — (280 ) Retained earnings 303,001 321,708 (3,733 ) (317,975 ) 303,001 Total shareholders’ equity 612,654 399,659 129,563 (529,222 ) 612,654 Total liabilities and shareholders’ equity $ 1,398,716 $ 499,172 $ 176,550 $ (672,592 ) $ 1,401,846 PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Thousands of dollars) For the year ended December 31, 2018 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Operating revenues, net $ 329,268 $ 263,679 $ 109,882 $ (28,406 ) $ 674,423 Expenses: Direct expenses 331,785 236,366 92,062 (28,406 ) 631,807 Selling, general, and administrative expenses 40,715 13,834 12,154 (18 ) 66,685 Total operating expenses 372,500 250,200 104,216 (28,424 ) 698,492 Loss on disposition of assets, net 774 — (21 ) — 753 Impairment of assets 31,824 — 77,200 — 109,024 Equity in loss of unconsolidated affiliate (188 ) — — — (188 ) Operating (loss) income (75,642 ) 13,479 (71,513 ) 18 (133,658 ) Equity in net earnings of consolidated subsidiaries 56,786 — — (56,786 ) — Interest expense 33,964 13 4 — 33,981 Other income, net (547 ) — 350 18 (179 ) 90,203 13 354 (56,768 ) 33,802 (Loss) earnings before income taxes (165,845 ) 13,466 (71,867 ) 56,786 (167,460 ) Income tax (benefit) expense (24,331 ) 1,785 (3,400 ) — (25,946 ) Net earnings (loss) $ (141,514 ) $ 11,681 $ (68,467 ) $ 56,786 $ (141,514 ) For the year ended December 31, 2017 Parent Non- Company Guarantor Guarantor Only (issuer) Subsidiaries Subsidiaries Eliminations Consolidated Operating revenues, net $ 310,449 $ 262,229 $ 23,871 $ (17,004 ) $ 579,545 Expenses: Direct expenses 326,152 212,691 24,860 (17,004 ) 546,699 Selling, general, and administrative expenses 41,134 12,462 221 — 53,817 Total operating expenses 367,286 225,153 25,081 (17,004 ) 600,516 Gain on disposition of assets, net 300 (2 ) — — 298 Impairment of assets 368 — — — 368 Equity in profit of unconsolidated affiliate 1,021 — (636 ) — 385 Operating (loss) income (58,526 ) 37,078 (574 ) — (22,022 ) Equity in net earnings of consolidated subsidiaries (38,553 ) — — 38,553 — Interest expense 32,161 22 — — 32,183 Other income, net (2,757 ) (2 ) (5 ) — (2,764 ) (9,149 ) 20 (5 ) 38,553 29,419 (Loss) earnings before income taxes (49,377 ) 37,058 (569 ) (38,553 ) (51,441 ) Income tax (benefit) expense (56,909 ) (1,138 ) (926 ) — (58,973 ) Net (loss) earnings $ 7,532 $ 38,196 $ 357 $ (38,553 ) $ 7,532 PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Thousands of dollars) For the year ended December 31, 2016 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Operating revenues, net $ 339,829 $ 293,329 $ 940 $ — $ 634,098 Expenses: Direct expenses 347,532 237,635 7,383 — 592,550 Selling, general, and administrative expenses 32,911 10,984 541 (18 ) 44,418 Total operating expenses 380,443 248,619 7,924 (18 ) 636,968 Loss on disposition of assets, net (3,350 ) — — (3,350 ) Equity in loss of unconsolidated affiliate (151 ) — — (151 ) Operating income (37,520 ) 44,710 (6,984 ) 18 224 Equity in net earnings of consolidated subsidiaries (22,182 ) — — 22,182 — Interest expense 30,585 46 13 — 30,644 Other income, net (3,284 ) (5 ) — 18 (3,271 ) 5,119 41 13 22,200 27,373 Earnings before income taxes (42,639 ) 44,669 (6,997 ) (22,182 ) (27,149 ) Income tax (benefit) expense (15,959 ) 15,490 — — (469 ) Net earnings $ (26,680 ) $ 29,179 $ (6,997 ) $ (22,182 ) $ (26,680 ) PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (Thousands of dollars) For the year ended December 31, 2018 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Net (loss) earnings $ (141,514 ) $ 11,681 $ (68,467 ) $ 56,786 $ (141,514 ) Unrealized gain on short-term investments 364 — — — 364 Changes in pension plan assets and benefit obligations (1 ) — — — (1 ) Tax effect (85 ) — — — (85 ) Currency translation adjustment — — (3,950 ) $ — (3,950 ) Total comprehensive income $ (141,236 ) $ 11,681 $ (72,417 ) $ 56,786 $ (145,186 ) For the year ended December 31, 2017 Parent Non- Company Guarantor Guarantor Only Subsidiaries Subsidiaries Eliminations Consolidated Net (loss) earnings $ 7,532 $ 38,196 $ 357 $ (38,553 ) $ 7,532 Unrealized gain on short-term investments 310 — — — 310 Changes in pension plan assets and benefit obligations (3 ) — — — (3 ) Tax effect (109 ) — — — (109 ) Total comprehensive (loss) income $ 7,730 $ 38,196 $ 357 $ (38,553 ) $ 7,730 For the year ended December 31, 2016 Parent Non- Company Guarantor Guarantor Only Subsidiaries Subsidiaries Eliminations Consolidated Net earnings $ (26,680 ) $ 29,179 $ (6,997 ) $ (22,182 ) $ (26,680 ) Unrealized loss on short-term investments 241 — — — 241 Other unrealized gain — — — — — Changes in pension plan assets and benefit obligations (39 ) — — — (39 ) Tax effect (113 ) — — — (113 ) Total comprehensive income $ (26,591 ) $ 29,179 $ (6,997 ) $ (22,182 ) $ (26,591 ) PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (Thousands of dollars) For the year ended December 31, 2018 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Net cash (used in) provided by operating activities $ 24,123 $ (16,952 ) $ 10,477 $ — $ 17,648 Investing activities: Purchase of property and equipment (40,865 ) — (2,311 ) — (43,176 ) Proceeds from asset dispositions 14,245 — — — 14,245 Purchase of short-term investments (284,481 ) — — — (284,481 ) Proceeds from sale of short-term investments 334,488 — — — 334,488 Loan to unconsolidated affiliate (274 ) — — — (274 ) Net cash provided by (used in) investing activities 23,113 — (2,311 ) — 20,802 Financing activities: Debt issuance costs (874 ) — — — (874 ) Repurchase of common stock (106 ) — — — (106 ) Proceeds on line of credit 34,295 — — — 34,295 Payments on line of credit (151,795 ) — — — (151,795 ) Proceeds from term loan 130,000 — — — 130,000 Due to/from affiliate, net (12,022 ) 17,139 (5,117 ) — — Net cash (used in) provided by financing activities (502 ) 17,139 (5,117 ) — 11,520 Effect of exchange rate changes on cash and cash equivalent — — (176 ) — (176 ) Increase (decrease) in cash, cash equivalents and restricted cash 46,734 187 2,873 — 49,794 Cash, cash equivalents and restricted cash at beginning of period 47 1,072 7,651 — 8,770 Cash, cash equivalents and restricted cash at end of period $ 46,781 $ 1,259 $ 10,524 $ — $ 58,564 (1) Net of the effect of business acquisitions. PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (Thousands of dollars) For the year ended December 31, 2017 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Net cash (used in) by operating activities $ (62,581 ) $ 40,628 $ 2,850 $ — $ (19,103 ) Investing activities: Purchase of property and equipment (56,757 ) — — — (56,757 ) Proceeds from asset dispositions 1,296 — — — 1,296 Purchase of short-term investments (637,980 ) — — — (637,980 ) Proceeds from sale of short-term investments 862,942 — — — 862,942 Payments of deposits on aircraft — — — — — Loan to third party (824 ) — — — (824 ) Business acquisitions net of cash acquired (130,788 ) — 4,144 — (126,644 ) Net cash used in investing activities 37,889 — 4,144 — 42,033 Financing activities: Repurchase of common stock (256 ) — — — (256 ) Proceeds on line of credit 152,150 — — — 152,150 Payments on line of credit (168,650 ) — — — (168,650 ) Due to/from affiliate, net 41,459 (41,656 ) 197 — — Net cash provided by (used in) financing activities 24,703 (41,656 ) 197 — (16,756 ) Increase (decrease) in cash, cash equivalents and restricted cash 11 (1,028 ) 7,191 — 6,174 Cash, cash equivalents and restricted cash at beginning of period 36 2,100 460 — 2,596 Cash, cash equivalents and restricted cash at end of period $ 47 $ 1,072 $ 7,651 $ — $ 8,770 PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (Thousands of dollars) For the year ended December 31, 2016 Parent Guarantor Non- Eliminations Consolidated Net cash provided by operating activities $ (46,738 ) $ 52,873 $ (6,699 ) $ — $ (564 ) Investing activities: Purchase of property and equipment (81,484 ) — (358 ) — (81,842 ) Proceeds from asset dispositions 14,983 — — — 14,983 Purchase of short-term investments (321,453 ) — — — (321,453 ) Proceeds from sale of short-term investments 316,543 — — — 316,543 Payments of deposits on aircraft (2,249 ) — — — (2,249 ) Loan to unconsolidated affiliate (1,200 ) — — — (1,200 ) Net cash used in investing activities (74,860 ) — (358 ) — (75,218 ) Financing activities: Repurchase of common stock (529 ) — — — (529 ) Proceeds on line of credit 264,700 — — — 264,700 Payments on line of credit (188,200 ) — — — (188,200 ) Due to/from affiliate, net 45,617 (52,445 ) 6,828 — — Net cash provided by (used in) financing activities 121,588 (52,445 ) 6,828 — 75,971 Decrease in cash (10 ) 428 (229 ) — 189 Cash, beginning of year 46 1,672 689 — 2,407 Cash, end of year $ 36 $ 2,100 $ 460 $ — $ 2,596

Asset Impairment

Asset Impairment	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Asset Impairment	ASSET IMPAIRMENT The below table summarizes the combined fair value of the assets that incurred impairments during the years ended December 31, 2018 , 2017 and 2016 , along with the amount of the impairment. The impairment charges were recorded in Impairment of assets in the consolidated statement of operations. See Note 1 for additional information. Year Ended December 31, 2018 2017 2016 Goodwill $ 61,643 $ — $ — Intangible assets 15,557 — — Aircraft and related inventory 31,824 368 407 Total $ 109,024 $ 368 $ 407 Goodwill impairment During the fourth quarter of 2018, the Company performed the impairment test of goodwill and recorded $61.6 million goodwill impairment relating to its Oil and Gas Segment. The Company determined that the fair value of its goodwill for the Oil and Gas segment was less than its carrying value and recorded a $61.6 million impairment charge. The reduction in value of goodwill in the Oil and Gas segment was primarily driven by further deterioration of market conditions and the Company’s forecast did not indicate a timely recovery sufficient to support the carrying values of the goodwill. Intangible asset impairment The impairment of assets during the fourth quarter of 2018 was comprised of $15.5 million related to customer relationship, Non-compete agreements and Tradenames from the HNZ offshore acquisition completed in December 2017. Aircraft and related inventory impairment During the fourth quarter of 2018, we recognized an impairment of $23.2 million related to a value of aircraft impairment primarily driven by the decline in demand for a specific medium model. The demand for this model continued to decline and the Company’s forecast did not indicate a timely recovery sufficient to support the carrying values of these assets. In connection with the evaluation of our current inventory levels and result of changes in expected future utilization for certain Medium aircraft. We also recorded charges of approximately $8.6 million to write-down of certain spare parts within inventories to its net realizable value. These charges were recorded as a direct reduction in the value of spare parts inventories to record them at net realizable value. This charge was recorded in Direct expenses on the Consolidated Statement of Operations.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS Chapter 11 Cases On March 14, 2019 (the “Petition Date”), the Company and its principal U.S. subsidiaries listed in Exhibit 99.1 hereto (collectively, the “Debtors”) filed voluntary petitions (the “Chapter 11 Cases”) in the United States Bankruptcy Court for the Northern District of Texas (the “Bankruptcy Court”) seeking relief under Chapter 11 of Title 11 of the United States Code (the “Bankruptcy Code”). The Debtors have requested joint administration of their Chapter 11 Cases under the caption In re: PHI, Inc., et al., Case No. 19-30923. See Note 1, Summary of Significant Accounting Policies - Chapter 11 Cases. New Term Loan Agreement As discussed in Note 8, Debt on March 13, 2019, we entered into the Term Loan Agreement. The full principal amount of the Term Loan is due March 11, 2023. Acceleration of Certain Debt Obligations As discussed in Note 8, Debt, the commencement of the Chapter 11 Cases constituted an event of default that accelerated the obligations under certain of our debt instruments. Any efforts to enforce payment of such financial obligations under such debt instruments are automatically stayed as a result of the filing of the Chapter 11 Cases. Notification of NASDAQ Delisting On March 15, 2019, the Nasdaq Stock Market (“Nasdaq”) notified us that, as a result of the filing of the Chapter 11 Cases and in accordance with applicable rules, Nasdaq has determined to delist the Company’s common stock from Nasdaq. The Company is considering whether to appeal this determination.

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Consolidated Accounts	12 Months Ended
	Dec. 31, 2018
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Schedule II - Valuation and Qualifying Consolidated Accounts	PHI, INC. AND SUBSIDIARIES Schedule II – Valuation and Qualifying Consolidated Accounts (Thousands of dollars) Additions Balance at Beginning Charged to Costs and Balance at End Description of Year Expenses Deductions (1) of Year Year ended December 31, 2018: Allowance for doubtful accounts $ 7,239 $ — $ 1,135 $ 6,104 Allowance for inventory 20,875 — 2,940 17,935 Allowance for contractual discounts 117,782 541,709 535,700 123,791 Allowance for uncompensated care 52,515 78,298 78,873 51,940 Year ended December 31, 2017: Allowance for doubtful accounts $ 6,021 $ 1,218 $ — $ 7,239 Allowance for inventory 17,305 3,570 — 20,875 Allowance for contractual discounts 111,856 480,645 474,719 117,782 Allowance for uncompensated care 46,310 78,883 72,678 52,515 Year ended December 31, 2016: Allowance for doubtful accounts $ 5,151 $ 870 $ — $ 6,021 Allowance for inventory 15,385 1,920 — 17,305 Allowance for contractual discounts 103,601 483,449 475,194 111,856 Allowance for uncompensated care 41,924 88,787 84,401 46,310 (1) Deductions from provisions represent losses or expenses for which the respective provisions were created. In the case of the provision for contractual discounts and uncompensated care, such deductions are reduced by recoveries of amounts previously written off.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Nature of Operations, Basis of Consolidation, and Other General Principles	Nature of Operations, Basis of Consolidation, and Other General Principles PHI, Inc. and its subsidiaries (“PHI,” the “Company,” “we,” “us,” or “our”) provide transportation services to, from, and among offshore facilities for customers engaged in the oil and gas exploration, development, and production industry. We provide these offshore services primarily in the United States and to a lesser extent in Canada, Trinidad, Australia, New Zealand, the Philippines, West Africa and the Middle East. We also provide air medical transportation services for hospitals and emergency service agencies, as well as aircraft maintenance and repair services to third parties in North America. The consolidated financial statements include the accounts of PHI, Inc. and its subsidiaries after the elimination of all intercompany accounts and transactions. We apply the equity method of accounting for investments in entities, if we have the ability to exercise significant influence over the operating and financial policies of the entity. We report our share of earnings or losses of equity investees in the accompanying Consolidated Statements of Operations as equity in (loss) profit of unconsolidated affiliate. At December 31, 2018 , Al A. Gonsoulin, Chairman of the Board and Chief Executive Officer, beneficially owned stock representing approximately 70.9% of the total voting power. As a result, he exercises control over the election of PHI’s directors and the outcome of matters requiring a shareholder vote. Chapter 11 Cases As of December 31, 2018, the Company’s total senior indebtedness was $630 million , consisting of (i) $500.0 million principal amount of our 5.25% Senior Notes due March 15, 2019 and (ii) $130.0 million principal amount of borrowings under its two -year term loan with the financing affiliate of its controlling shareholder (in each case excluding debt issuance costs). The Company also had $19.8 million of letters of credit outstanding at December 31, 2018. As of December 31, 2018, the Company had approximately $159.5 million of aggregate lease commitments. As discussed further elsewhere herein, the Company borrowed an additional $70 million on March 13, 2019. Beginning in late 2017, the Company considered its options for refinancing its unsecured senior notes due March 15, 2019. However, in light of the challenging operating environment for companies providing offshore energy services generally, the financing market was constrained and the Company was not able to identify a refinancing option that it believed provided a suitable capital platform to promote the best interests of the Company and its stakeholders. In the fall of 2018, the Company announced that it had engaged financial advisors to assist the Company in exploring and evaluating a broad range of potential strategic alternatives. After working closely with the Company’s advisors, communicating with the Company’s various stakeholders, and carefully evaluating all possible options, the Board concluded that pursuing Chapter 11 protection was the most appropriate course of action to address the Company’s maturing debt and strengthen its balance sheet. Prior to the maturity of the Company’s unsecured senior notes, on March 14, 2019 (the “Petition Date”), the Company and its principal U.S. subsidiaries. PHI Tech Services, Inc., AM Equity Holdings, L.L.C., PHI Air Medical, L.L.C. and PHI Helipass, L.L.C. (together with the Company, collectively, the “Debtors”) filed voluntary petitions (the “Chapter 11 Cases”) in the United States Bankruptcy Court for the Northern District of Texas (the “Bankruptcy Court”) seeking relief under Chapter 11 of Title 11 of the United States Code (the “Bankruptcy Code”). The Debtors have requested joint administration of their Chapter 11 Cases under the caption In re: PHI, Inc., et al., Main Case No. 19-30923. The Debtors continue to operate their businesses and manage their properties as “debtors-in-possession” under the jurisdiction of the Bankruptcy Court and in accordance with the applicable provisions of the Bankruptcy Code and orders of the Bankruptcy Court. To ensure their ability to continue operating in the ordinary course of business, the Debtors have filed with the Bankruptcy Court motions seeking a variety of “first-day” relief (collectively, the “First Day Motions”), including authority to pay employee wages and benefits, honor customer programs, and pay utilities providers, insurance providers and other vendors and suppliers in the ordinary course for all goods and services provided after the Petition Date. We currently retain the exclusive right to propose a Chapter 11 plan of reorganization. If the Bankruptcy Court terminates that right, however, or the exclusivity period expires, our ability to achieve confirmation of a Chapter 11 plan of reorganization could be materially adversely affected. Going Concern The Company expects to continue operations in the normal course during the pendency of the Chapter 11 Cases described immediately above under the heading "Chapter 11 Cases". The significant risks and uncertainties related to the company’s Chapter 11 Case raise substantial doubt about the company's ability to continue as a going concern. The consolidated financial statements have been prepared on a going concern basis of accounting, which contemplates continuity of operations, realization of assets, and satisfaction of liabilities and commitments in the normal course of business. The consolidated financial statements do not include any adjustments that might result from the outcome of the going concern uncertainty.
Use of Estimates	Use of Estimates The preparation of financial statements is in conformity with accounting principles generally accepted in the United States of America (“GAAP”), which requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates. Significant estimates include: Estimates of contractual allowances applicable to billings in the Air Medical segment, Valuation reserve related to obsolete and excess inventory, Reserves related to unpaid accounts, Depreciable lives and salvage values of property and equipment, Valuation allowance for deferred tax assets, Fair values of assets acquired and liabilities assumed, Income taxes, Healthcare insurance claims and workers’ compensation liability, and Impairment of long-lived assets, Impairment of Goodwill and Intangible assets.
Cash and Cash Equivalents	Cash and Cash Equivalents We consider all highly liquid investments with maturities of three months or less , when purchased, to be cash equivalents.
Trade Receivables, net	Trade Receivables, net Trade and other receivables are stated at net realizable value. Air Medical trade receivables are presented net of allowances for contractual discounts and uncompensated care. We estimate contractual allowances and uncompensated care based on historical collection experience by payor category. The main payor categories are Medicare, Medicaid, private insurance, and self-pay. We analyze our historical payment of accounts by payor category on a monthly basis, and adjust our accounts receivable allowance based upon each category’s historical collection percentage plus any adjustments for current trends in payor behavior. Provisions for contractual discounts and uncompensated care that we applied to our Air Medical trade receivables (expressed as a percentage of total segment accounts receivable at December 31 were as follows: 2018 2017 Allowance for contractual discounts 51% 53% Allowance for uncompensated care 22% 24%
Short-term Investments	Short-term Investments Short-term investments consist of commercial paper, debt issued by the U.S. government or its agencies, and corporate bonds and notes, which represent funds available for current operations. In accordance with GAAP, these short-term investments are classified as available for sale.
Inventories of Spare Parts	Inventories of Spare Parts The Company’s inventories are stated at average cost and consist primarily of spare aircraft parts. Portions of the Company’s inventories are used parts that are often exchanged with parts removed from aircraft, reworked to a useable condition according to manufacturers’ and FAA specifications, and returned to inventory. Reusable aircraft parts are included in inventory at the average cost of comparable parts. The rework costs are expensed as incurred. The Company also records an allowance for obsolete and slow-moving parts, relying principally on specific identification of such inventory.
Property and Equipment	Property and Equipment The Company records its property and equipment at cost less accumulated depreciation. For financial reporting purposes, the Company uses the straight-line method to compute depreciation based upon estimated useful lives of 5 to 15 years for flight equipment and 3 to 10 years for other equipment. Leasehold improvements are amortized over the shorter of the life of the respective asset or the term of the lease agreement and range from 6 to 10 years. The salvage value used in calculating depreciation of aircraft ranges from 25% to 54% of the aircraft’s carrying value, based upon historical aircraft sales data. The cost of scheduled inspections and modifications for flight equipment are charged to maintenance expense as incurred. We charge maintenance and repair costs to earnings as the costs are incurred. The cost of certain aircraft components are covered under contractual arrangements with the applicable aircraft manufacturer, commonly referred to as “power-by-the-hour” contracts. Under these agreements, we are charged an agreed amount per hour of flying time. The costs charged under these contractual arrangements are recognized in the period in which the flight hours occur. To the extent that we have not yet been billed for costs incurred under these arrangements, these costs are included in accrued expenses on our consolidated balance sheets. Modifications that enhance the operating performance or extend the useful lives of the aircraft are capitalized and depreciated over the remaining life of the aircraft. Upon selling or otherwise disposing of property and equipment, the Company removes the cost and accumulated depreciation from the accounts and reflects any resulting gain or loss in earnings at the time of sale or other disposition. The Company reviews its long-lived tangible assets for impairment annually, or more frequently if events or a change of circumstances indicate that an impairment may have occurred. In such evaluation, the estimated future undiscounted cash flows generated by a particular asset group are compared with the book value of the asset group to determine if an impairment charge is necessary. Similar aircraft model types are grouped together for impairment testing purposes. The Company measures recoverability of assets to be held and used by comparing the carrying amount of an asset to future undiscounted net cash flows that it expects the asset to generate. When the Company determines that an asset is impaired, the Company recognizes that impairment amount, which is measured by the amount that the carrying value of the asset exceeds its fair value. In addition to the periodic review of its active long-lived tangible assets for impairment when circumstances warrant, the Company also performs a review of its parked aircraft not expected to return to service annually or whenever changes in circumstances indicate the carrying amount of an aircraft may not be recoverable. Management estimates the fair value of each aircraft not expected to return to service by considering items such as the aircraft’s age, length of time parked, likelihood of return to active service, and actual recent sales of similar aircraft. For more significant aircraft carrying values, we obtain an estimate of the fair value of the parked aircraft from third-party appraisers for use in our determination of fair value estimates. The Company records an impairment charge when the carrying value of a parked aircraft not expected to return to active service exceeds its estimated fair market value. During the twelve months ended December 31, 2018 , we sold or disposed of one heavy, three medium and one light aircraft and related parts inventory utilized in our Oil and Gas segment and one light aircraft in our Air Medical segment. Cash proceeds totaled $14.2 million , resulting in a loss of $0.8 million . These aircraft no longer met our strategic needs. During the twelve months ended December 31, 2017 , we sold or disposed of six medium, one fixed wing aircraft and related parts inventory previously utilized in our Oil and Gas segment. Cash proceeds totaled $ 1.3 million , resulting in a loss of $ 0.3 million . These aircraft no longer met our strategic needs. During the twelve months ended December 31, 2016, we sold twelve light, eleven medium aircraft, and related parts inventory previously utilized in our Oil and Gas segment. Cash proceeds totaled $15.0 million , resulting in a gain of $3.3 million . These aircraft no longer met our strategic needs.
Impairment Losses for aircraft	Impairment Losses for Aircraft The Company estimates cash flows and asset appraisals based upon historical data adjusted for the Company’s best estimate of expected future market performance. If an asset group fails the undiscounted cash flow test or appraisal value, the Company compares the market value to the book value of each asset group in order to determine if impairment exists (considered Level 3, as defined by ASC 820, Fair Value Measurements and Disclosures). If impairment exists, the book value of the asset group is reduced to its estimated fair value. We recorded an impairment loss in the year ended December 31, 2018 for two light, seventeen medium and one heavy aircraft and related spare parts in our Oil and Gas segment. The carrying value of these aircraft was $109.6 million . Following a market analysis, we determined that the market value for these aircraft is $85.2 million (based on a Level 3 review, as defined by ASC 820, Fair Value Measurements and Disclosures). As a result of this analysis, we recorded an aggregate non-cash pre-tax impairment loss of $23.2 million for 2018 . We had $0.4 million impairment losses in the year ended December 31, 2017 . We had $0.4 million impairment losses for the year ended December 31, 2016 .
Fair Value of Assets and Liabilities Acquired and Identification of Associated Goodwil and Intangible Assets	Fair Value of Assets and Liabilities Acquired and Identification of Associated Goodwill and Intangible Assets In conjunction with each acquisition we make, we must allocate the cost of the acquired entity to the assets and liabilities assumed based on their estimated fair values at the date of acquisition. As additional information becomes available, we may adjust the original estimates within a short time period subsequent to the acquisition. In addition, we are required to recognize intangible assets separately from goodwill. Determining the fair value of assets and liabilities acquired, as well as intangible assets that relate to such items as customer relationships, contracts, trade names and non-compete agreements involves professional judgment and is ultimately based on acquisition models and management’s assessment of the value of the assets acquired, and to the extent available, third party assessments. Intangible assets with finite lives are amortized over their estimated useful life as determined by management. Whenever events or changes in circumstances indicate that the carrying amount of the intangible assets may not be recoverable, the intangible assets will be reviewed for impairment. Goodwill is not amortized but instead is periodically assessed for impairment. Uncertainties associated with these estimates include fluctuations in economic obsolescence factors in the area and potential future sources of cash flow. We cannot provide assurance that actual amounts will not vary significantly from estimated amounts.
Goodwill	Goodwill Goodwill represents the amount the purchase price exceeds the fair value of net assets acquired in a business combination. Goodwill has an indefinite useful life and is not amortized, but is assessed for impairment annually or when events or changes in circumstances indicate that a potential impairment exists. The Company performs the goodwill impairment test on an annual basis during the fourth quarter or on an interim basis if events or circumstances indicate that the fair value of the asset has decreased below its carrying value. The company performed its goodwill impairment test in the fourth quarter. In order to estimate the fair value of the reporting units (which is consistent with the reported business segments), the Company used a weighting of the discounted cash flow method and the public company guideline method of determining fair value of each reporting unit. The Company weighted the discounted cash flow method 80% and the public company guideline method 20% due to differences between the Company’s reporting units and the peer companies’ size, profitability and diversity of operations. These fair value estimates were then compared to the carrying value of the reporting units. If the fair value of the reporting unit exceeds the carrying amount, no impairment loss is recognized. If the estimated fair value of the reporting unit is below the carrying value, then an impairment is recorded, which represents the amount by which a reporting unit’s carrying value exceeds its fair value. The inputs used to determine fair value were classified as level 3 in the fair value hierarchy. A significant amount of judgment was involved in performing these evaluations since the results are based on estimated future events. At December 31, 2018, the Company’s accumulated impairments of goodwill was $61.6 million . As of December 31, 2018 there is no remaining goodwill in our financial statements. (see note 18).
Other Intangible Assets	Other Intangible Assets In connection with our acquisition of the HNZ Offshore Business, we also recognized in the fourth quarter of 2017 intangible assets for customer relationship, non-compete and tradenames. Intangible assets with finite useful lives are amortized over estimated useful lives on a straight-line basis. The Company reviews its intangible assets for impairment annually, or more frequently if events or a change of circumstances indicate that the carrying amount of any such asset may not be recoverable. The determination of recoverability is made based upon the estimated undiscounted future net cash flows. In such evaluation, the estimated future undiscounted cash flows generated by a particular asset group are compared with the book value of the asset group to determine if an impairment charge is necessary. The Company measures recoverability of assets to be held and used by comparing the carrying amount of an asset to future undiscounted net cash flows that it expects the asset to generate. When the Company determines that an asset is impaired, the Company recognizes that impairment amount, which is measured by the amount that the carrying value of the asset exceeds its fair value. The estimated fair values for these assets were determined using discounted future cash flows. The significant level 3 unobservable inputs used in the determination of the fair value of these assets were the estimated future cash flows and the weighted average cost of capital ("WACC").
Deferred Financing Costs	Deferred Financing Costs Costs incurred to obtain long-term debt financing are deferred and amortized ratably over the term of the related debt agreement.
Self-Insurance	Self-Insurance The Company maintains a self-insurance program for a portion of its healthcare costs. Self-insurance costs are accrued based upon the aggregate of the liability for reported claims and the estimated liability for claims incurred but not reported. The Company’s insurance retention was $250,000 per claim through December 31, 2018 . As of December 31, 2018 and 2017 , the Company had $1.8 million and $1.3 million , respectively, of accrued liabilities related to healthcare claims. There is also a $0.5 million deductible per incident on our workers’ compensation program. We have accrued $1.9 million and $2.9 million for the years 2018 and 2017 , respectively, related to workers’ compensation claims. The Company owns an offshore insurance company to realize savings in reinsurance costs on its insurance premiums. We paid $0.3 million and $0.5 million , respectively, to this captive company in 2018 and 2017 , which were eliminated in consolidation. The results of the captive are fully consolidated in the accompanying consolidated financial statements.
Revenue Recognition	Revenue Recognition In 2014, the Financial Accounting Standard Board ("the FASB") issued ASC 606, Revenue from Contracts with Customers (“ASC 606”), replacing the existing accounting standard and industry specific guidance for revenue recognition with a five-step model for recognizing and measuring revenue from contracts with customers. The underlying principle of the new standard is to recognize revenue to depict the transfer of goods or services to customers at the amount expected to be collected. ASC 606 became effective on January 1, 2018 and we adopted it using the modified retrospective method applied to open contracts and only to the version of the contracts in effect as of January 1, 2018. Prior period amounts have not been adjusted and continue to be reflected in accordance with our historical accounting. There was no impact on the condensed consolidated financial statements and no cumulative effect adjustment was recognized. In general, under ASC 606, we recognize revenue when a service or good is sold to a customer and there is a contract. At contract inception, we assess the goods and services promised in our contracts with customers and identify all performance obligations for each distinct promise that transfers a good or service (or bundle of goods or services) to the customer. To identify the performance obligations, we consider all goods or services promised in the contract, whether explicitly stated or implied based on customary business practices. Revenue is recognized when control of the identified distinct goods or services has been transferred to the customer, the transaction price has been determined and allocated to the performed performance obligations and we have determined that collection has occurred or is probable of occurring. We measure revenue as the amount of consideration we expect to receive in exchange for the services provided. Taxes collected from customers and remitted to governmental authorities and revenues are reported on a net basis in the financial statements. Thus, we exclude taxes imposed on the customer and collected on behalf of governmental agencies to be remitted to these agencies from the transaction price in determining the revenue related to contracts with a customer. Oil & Gas Revenue Recognition - We provide helicopter services to oil and gas customers operating in the Gulf of Mexico and a number of foreign countries. Revenues are recognized when performance obligations are satisfied over time in accordance with contractual terms, in an amount that reflects the consideration the Company expects to be entitled to in exchange for services rendered. Air Medical Revenue Recognition - We provide helicopter services to hospitals and emergency service providers in several U.S. states, or to individual patients in the U.S. in which case we are paid by either a commercial insurance company, federal or state agency, or the patient. Our Air Medical segment operates primarily under the independent provider model and, to a lesser extent, under the traditional provider model. Revenues related to the independent provider model services are recorded in the period in which we satisfy our performance obligations under contracts by providing our services to our customers based upon established billing rates net of contractual allowances under agreements with third party payors and net of uncompensated care allowances. These amounts are due from patients, third-party payors (including health insurers and government programs), and others and includes variable consideration for retroactive revenue adjustments due to settlement of audits, reviews, and investigations. Generally, we bill the patients and third-party payors several days after the services are performed. Revenues generated under the traditional provider model are recognized as performance obligations are satisfied over time in accordance with contractual terms, in an amount that reflects the consideration the Company expects to be entitled in exchange for services rendered. Oil & Gas Performance Obligations - A performance obligation arises under contracts with customers to render services and is the unit of account under ASC 606. Operating revenue from our Oil and Gas segment is derived mainly from fixed-term contracts with our customers, a substantial portion of which are competitively bid. A small portion of our Oil and Gas segment revenue is derived from providing services on an "ad-hoc" basis. Our fixed-term contracts typically have original terms of one to seven years (subject to provisions permitting early termination on relatively short notice by the customers), with payment in U.S. dollars. We account for services rendered separately if they are distinct and the services are separately identifiable from other items provided to a customer and if a customer can benefit from the services rendered on its own or with other resources that are readily available to the customer. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. Within this contract type for helicopter services, we determined that each contract has a single distinct performance obligation. These services include a fixed monthly rate for a particular model of aircraft, and flight hour services, which represents the variable component of a typical contract with a customer. Rates for these services vary depending on the type of services provided and can be based on a per flight hour, per day, or per month basis. We also provide services to clients on an “ad hoc” basis, which usually entails a shorter contract notice period and duration. The charges for ad hoc services are based on an hourly rate or a daily or monthly fixed fee plus additional fees for each hour flown. The nature of our variable charges within our flight services contracts are not effective until a customer-initiated flight order and the actual hours flown are determined; therefore, the associated flight revenue generally cannot be reasonably and reliably estimated beforehand. A contract’s standalone selling prices are determined based upon the prices that we charge for our services rendered. The majority of our revenue is recognized as performance obligations satisfied over time, by measuring progress towards satisfying the contracted services in a manner that best depicts the transfer of services to the customer, which is generally represented by a period of 30 days or less. We typically invoice customers on a monthly basis with the term between invoicing and when the payment is due typically being between 30 and 60 days. Air Medical Performance Obligations - Performance obligations are determined based upon the nature of the services provided. Under the independent provider model, we measure the performance obligation from the moment the patient is loaded into the aircraft until it reaches its destination. Under this model, we have no fixed revenue stream and compete for transport referrals on a daily basis with other independent operators in the area. As an independent provider, we bill for our services on the basis of a flat rate plus a variable charge per patient-loaded mile, regardless of aircraft model, and are typically compensated by private insurance, Medicaid or Medicare, or directly by transported patients who self-pay. We recognize revenues for performance obligations satisfied at a point in time, which generally relate to patients receiving air medical services when: (1) services are provided; and (2) we do not believe the patient requires additional services. For the independent provider model, we determine the transaction price based upon gross charges for services provided reduced by contractual adjustments provided to third-party payors, discounts provided to uninsured patients in accordance with Company policy, and/or implicit price concessions provided to uninsured patients. We determine estimates of contractual adjustments and discounts based upon contractual agreements, our discount policy, and historical experience. We determine our estimate of implicit price concessions based upon our historical collection experience with these classes of patients using a portfolio approach as a practical expedient to account for patient contracts as collective groups, rather than individually. The financial statement effects of using this practical expedient are not materially different from an individual contract approach. Under the traditional provider model, we contract directly with the customer to provide their transportation services. These contracts are typically awarded or renewed through competitive bidding and typically permit early termination by the customer on relatively short notice. As a traditional provider, we typically bill a fixed monthly rate for aircraft availability and an hourly rate for flight time. For each of these types of helicopter services, we have determined that each has a single distinct performance obligation. Traditional provider models services include fixed monthly rate for a particular model of aircraft, and flight hour services, which represents the variable component of a typical contract with a customer. Rates for these services vary depending on the type of services provided and can be based on a per flight hour, per day, or per month basis. The variable charges within such contracts are not effective until the customer initiates a flight order and the actual hours flown are determined; therefore, the associated revenue generally cannot be reasonably and reliably estimated beforehand. For the traditional provider model, we determine the transaction price based upon standard charges for goods and services provided. Independent provider revenues are recorded net of contractual allowances under agreements with third party payors and estimated uncompensated care at the time the services are provided. Contractual allowances and uncompensated care are estimated based on historical collection experience by payor category (consisting mainly of private insurance, Medicaid, Medicare, and self-pay). The allowance percentages calculated are applied to the payor categories, and the necessary adjustments are made to the revenue allowance. Agreements with third-party payors typically provide for payments at amounts less than established charges. We estimate contractual allowances and uncompensated care based on historical collection experience by payor category. The main payor categories are Medicaid, Medicare, private insurance, and self-pay. Changes in payor mix, reimbursement rates and uncompensated care rates are the factors most subject to sensitivity and variability in calculating our allowances. We compute a historical payment analysis of accounts by category. The allowance percentages calculated are applied to the payor categories, and the necessary adjustments are made to the revenue allowance. In our Air Medical Segment, the allowance for contractual discounts against outstanding accounts receivable was $123.8 million , $117.8 million , and $111.9 million as of December 31, 2018 , 2017 , and 2016 , respectively, and the allowance for uncompensated care against outstanding accounts receivable was $51.9 million , $52.5 million , and $46.3 million as of December 31, 2018 , 2017 , and 2016 , respectively. Included in the allowance for uncompensated care above is the value of services to patients who are unable to pay when it is determined that they qualify as charity care. The value of these services was $7.2 million , $7.1 million , and $8.8 million for the years ended December 31, 2018 , 2017 , and 2016 , respectively. The estimated cost of providing charity services was $1.7 million , $1.6 million , and $1.9 million for the years ended December 31, 2018 , 2017 , and 2016 , respectively. The estimated costs of providing charity services are based on a calculation that applies a ratio of costs to the charges for uncompensated charity care. The ratio of costs to charges is based on the Air Medical independent provider model’s total expenses divided by gross patient service revenue. In determining the allowance estimates for our Air Medical segment’s billing, receivables and revenue, we utilize the prior twelve months’ payment history and current trends in payor behavior by each separate payor group, which we evaluate on a state by state basis. A percentage of amounts collected compared to the total invoice is determined from this process and applied to the current month’s billings and receivables. If a receivable related to the self-pay category is outstanding twelve months or greater, we record a reserve equal to 100% of the receivable. Receivables related to other payor categories are scrutinized when they are outstanding for nine months or longer and additional allowances are recorded if warranted. Provisions for contractual discounts and estimated uncompensated care that we applied to our Air Medical revenues (expressed as a percentage of total independent provider model billings) were as follows: Year Ended December 31, 2018 2017 2016 Provision for contractual discounts 67 % 66 % 67 % Provision for uncompensated care 8 % 7 % 6 % Amounts attributable to Medicaid, Medicare, private insurance, and self-pay as a percentage of net Air Medical independent provider model revenues were as follows: Year Ended December 31, 2018 2017 2016 Insurance 71 % 72 % 72 % Medicare 20 % 18 % 18 % Medicaid 8 % 9 % 9 % Self-Pay 1 % 1 % 1 % As of December 31, 3018 and December 31, 2017, receivables related to our (i) Oil and Gas segment were $74.1 million and $86.9 million , (ii) Air Medical segment were $90.2 million and $76.6 million and (iii) Technical Services segment were $4.1 million and $4.7 million , respectively. Contract assets and contract liabilities were immaterial as of December 31, 2018. Our contracts typically include termination clauses that allow both parties to terminate existing contracts with a 30 to 180 day notice period. We generally have a right to consideration in an amount that corresponds directly with the value to the customer of the entity's performance completed to date and may recognize revenue in the amount to which the entity has a right to invoice. We have elected to use the invoice practical expedient for revenue recognized when performance obligations are satisfied over time. In addition, payment for goods and services rendered is typically due in the subsequent month following satisfaction of our performance obligation. Our Technical Services segment provides helicopter flight services and helicopter repair and overhaul services for existing flight operations customers that own their own aircraft. Under this segment, we periodically provide certain services to governmental customers, including our agreement to operate six aircraft for the National Science Foundation in Antarctica. Under this segment, we also offer certain software as a service to our Oil and Gas customers. Revenues are recognized when performance obligations are satisfied in accordance with contractual terms, in an amount that reflects the consideration we expect to be entitled to in exchange for services rendered. For these helicopter services, we determined that each has a single distinct performance obligation. The following table presents the Company’s revenues by segment disaggregated by type (in thousands): For the Year Ended December 31, 2018 2017 Service Revenue Oil & Gas $ 380,238 $ 298,398 Air Medical 257,132 257,273 Technical Services 37,053 23,874 Total Services $ 674,423 $ 579,545 Air Medical Revenue Traditional provider model $ 45,220 $ 44,147 Independent provider model 211,912 213,126 Total Air Medicals Revenues $ 257,132 $ 257,273 Under a contract that commenced on September 29, 2012, our Air Medical affiliate provided multiple products and services to a customer in the Middle East, including helicopter leasing, emergency medical helicopter flight services, aircraft maintenance, provision of spare parts and insurance coverage for the customer-owned aircraft, training services, and base construction. The initial contract expired in late September 2015 and was extended through September 30, 2016, when it lapsed. Each of the major deliverables mentioned above qualify as separate units of accounting under the accounting guidance for such arrangements. The selling price for each service was determined based upon third-party evidence and estimates.
Income Taxes	Income Taxes Income taxes are accounted for in accordance with the provisions of Accounting Standards Codification 740, Income Taxes . The Company provides for income taxes using the asset and liability method under which deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. The deferred tax assets and liabilities measurement uses enacted tax rates that are expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The Company recognizes the effect of any tax rate changes in income of the period that includes the enactment date. In connection with recording deferred income tax assets and liabilities, the Company establishes valuation allowances when necessary to reduce deferred income tax assets to amounts that it believes are more likely than not to be realized. The Company evaluates its deferred tax assets quarterly to determine whether positive or negative adjustments to its valuation allowances are appropriate in light of changes in facts or circumstances, such as changes in tax law or interactions with taxing authorities. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion of the deferred tax assets will not be realized. Adjustments to the amount of our valuation allowances can materially impact our financial condition and results of operations. The Tax Cuts and Jobs Act (the "Act") was enacted on December 22, 2017. The Act reduced the U.S. federal corporate tax rate from 35% to 21%. Following the enactment of Tax Reform Legislation in December 2017, the SEC staff issued Staff Accounting Bulletin 118 - "Income Tax Accounting Implications of the Tax Cuts and Jobs Act" (SAB 118), which provides for a measurement period of up to one year from the enactment date to complete accounting under GAAP for the tax effects of the legislation. In connection with the initial analysis of the Act, the Company remeasured its net deferred tax liability at December 31, 2017 and provisionally recognized a net benefit of $49.2 million in its consolidated statement of operations for the year ended December 31, 2017. In the fourth quarter of 2018, the Company finalized it accounting under the Act and recorded immaterial differences from the provisional amounts previously recorded. The Act also includes provisions to tax a new class of income called Global Intangible Low-Taxed Income (“GILTI”). Under GAAP, the Company is allowed to make an accounting policy choice of either (i) treating taxes due on future U.S. inclusions in taxable income related to GILTI as a current period expense when incurred or (ii) factoring such amounts into the measurement of deferred taxes. The Company has evaluated each of the alternatives and has elected to account for GILTI as a current period expense. The Company does not have a GILTI inclusion in 2018; therefore, no tax expense with respect to GILTI has been recorded for the year ended December 31, 2018.
Earnings per Share	Earnings per Share Basic earnings per share is computed by dividing earnings (loss) during the period by the weighted average number of voting and non-voting shares outstanding during each period. Diluted earnings per share is computed by dividing net income (loss) during the period by the weighted average number of shares of common stock that would have been outstanding assuming the issuance of potentially dilutive shares of common stock, as if such shares were outstanding during the reporting period, net of shares to be repurchased using the treasury stock method. Dilutive shares for this purpose assumes restricted stock unit awards have vested.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of trade accounts receivables. Approximately 10.7% of our trade accounts receivables at December 31, 2018 were owed by an overseas customer. For a variety of reasons, the Company believes it will be paid all or substantially all of the amounts due under these receivables. Accordingly, the Company does not believe that it had significant credit risk at December 31, 2018 with respect to these overseas trade accounts receivable specifically or its aggregate trade accounts receivable generally. PHI conducts a majority of its business with major and independent oil and gas exploration and production companies with operations in the Gulf of Mexico. The Company also provides services to major medical centers. The Company continually evaluates the financial strength of its customers, but generally does not require collateral to secure its customer receivables. The Company establishes an allowance for doubtful accounts based upon factors pertaining to the credit risk of specific customers, current market conditions, and other information. Amounts are charged off as uncollectible when collection efforts have been exhausted. The allowance for doubtful accounts was $6.1 million and $7.2 million at December 31, 2018 and 2017 , respectively. Trade receivables representing amounts due pursuant to air medical independent provider model services are carried net of an allowance for estimated contractual adjustments and uncompensated care on unsettled invoices. The Company monitors its collection experience by payor category within the Air Medical segment and updates its estimated collections to be realized as deemed necessary. In our Air Medical segments, the allowance for contractual discounts was $123.8 million , $117.8 million , and $111.9 million as of December 31, 2018 , 2017 , and 2016 , respectively, and the allowance for uncompensated care was $51.9 million , $52.5 million , and $46.3 million as of December 31, 2018 , 2017 , and 2016 , respectively. The Company’s two largest oil and gas customers accounted for 24% of consolidated operating revenues for the year ended December 31, 2018 , 23% for the year ended December 31, 2017 , and 24% for the year ended December 31, 2016 . The Company also carried accounts receivable from these same customers totaling 20% and 16% of net trade receivables on December 31, 2018 and 2017 , respectively. The customer base of our Air Medical and Technical Services operations has traditionally been less concentrated than the customer base of our Oil and Gas operations. Over the past three years, none of our current Air Medical or Technical Services customers accounted for more than 2% of our consolidated operating revenues. One of our former Air Medical customers, however, did account for 5% of our consolidated operating revenues for 2016. The Company also carried accounts receivable from its largest customer totaling 13.5% and 10.0% of net trade receivables on December 31, 2018 and 2017 , respectively. Substantially all of the Company’s cash is maintained in one financial institution in amounts that typically exceed federally insured limits. The Company has not experienced any losses in such accounts and based on current circumstances does not believe that it is exposed to significant credit risk.
Foreign Currency Translation	Foreign Currency Translation Our consolidated financial statements are reported in U.S. dollars. Our foreign subsidiaries maintain their records primarily in the currency of the country in which they operate. Assets and liabilities of foreign subsidiaries in non-highly inflationary economies are translated into U.S. dollars using rates of exchange at the balance sheet date. Translation adjustments are recorded in other comprehensive income (loss). Revenues and expenses are translated at rates of exchange in effect during the year. Transaction gains and losses are recorded in net earnings (loss).
New Accounting Pronouncements	Effective January 1, 2017, we adopted Accounting Standards Update (“ASU”) 2016-09, Compensation - Stock Compensation (Topic 718) : Improvements to Employee Share-Based Payment Accounting, which was issued by the Financial Accounting Standards Board (“FASB”) in March 2016. This new standard requires that excess tax benefits and deficiencies resulting from stock-based compensation awards vesting and exercises be recognized in the income statement. Previously, these amounts were recognized in additional paid-in capital. As a result, during the first quarter of 2017 we recorded a cumulative-effect adjustment of $1.0 million increasing retained earnings and decreasing deferred tax liability on our balance sheet dated December 31, 2017. Accordingly, we recorded income tax expense of $0.9 million in our consolidated statement of operations for the year ended December 31, 2017, in recognition of excess tax deficiencies related to equity compensation. Under this new standard, the corresponding cash flows are now reflected in cash provided by operating activities instead of financing activities, as was previously required. On January 26, 2017, the FASB issued ASU No. 2017-04, Intangibles - Goodwill and Other (Topic 350) : Simplifying the Test for Goodwill Impairment (ASU 2017-04). ASU 2017-04 removes the requirement to compare the implied fair value of goodwill with the carrying amount as part of Step 2 of the goodwill impairment test. Under the new standard, the goodwill impairment loss will be measured as the excess of a reporting unit's carrying amount over its fair value, not exceeding the total amount of goodwill allocated to that reporting unit, which may increase the frequency of goodwill impairment charges if a future goodwill impairment test does not pass the Step 1 evaluation. ASU 2017-04 is effective prospectively for periods beginning on or after December 15, 2019, with early adoption permitted. The Company adopted ASU 2017-04 effective January 1, 2018. The Company performed its goodwill impairment test under the new standard in fourth quarter of 2018. In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes , which requires that deferred tax assets and liabilities be classified as noncurrent in a classified balance sheet. PHI, Inc. adopted this ASU in the fourth quarter of 2017 on a prospective basis. Beginning with the December 31, 2017 balances, all deferred taxes were classified as non-current. Periods prior to December 31, 2017 were not retrospectively adjusted. In 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (ASU 2016-18). ASU 2016-18 eliminates the need to reflect transfers between cash and restricted cash in operating, investing, and financing activities in the statements of cash flows. In addition, the net change in cash and cash equivalents during the period includes amounts generally described as restricted cash or restricted cash equivalents. The Company adopted ASU 2016-18 retrospectively effective January 1, 2018. New Accounting Pronouncements In February 2016, the FASB issued ASU 2016-02 , Leases (Topic 842) (ASC 842). ASC 842 replaces the existing guidance on leasing transactions in ASC 840 and requires lessees to recognize on the balance sheet a lease liability and a right-of-use asset for all leases. ASC 842 also changes the recognition, measurement, and presentation of expense associated with leases and provides clarification regarding the identification of certain components of contracts that would represent a lease. ASC 842 is effective for fiscal years beginning after December 15, 2018 and the Company adopted the new standard effective January 1, 2019.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Provisions for Contractual Discounts and Uncompensated Care Applied to Air Medical Trade Receivables Expressed as Percentage of Total Segment Accounts Receivable	Provisions for contractual discounts and uncompensated care that we applied to our Air Medical trade receivables (expressed as a percentage of total segment accounts receivable at December 31 were as follows: 2018 2017 Allowance for contractual discounts 51% 53% Allowance for uncompensated care 22% 24%
Schedule of Intangible Assets	Our intangible assets by types consist of the following (in thousands): Estimated Useful Lives Gross Amount Accumulated Amortization Impairments of assets Net Balance Customer Relationship 15 11,622 (581 ) (11,041 ) — Non-Compete Agreements 5 900 (135 ) (765 ) — Tradenames 7 4,201 (450 ) (3,751 ) — Total 16,723 (1,166 ) (15,557 ) —
Schedule of Provisions for Contractual Discounts and Estimated Uncompensated Care Applied to Air Medical Revenues Expressed as Percentage of Total Independent Provider Model Billings	Provisions for contractual discounts and estimated uncompensated care that we applied to our Air Medical revenues (expressed as a percentage of total independent provider model billings) were as follows: Year Ended December 31, 2018 2017 2016 Provision for contractual discounts 67 % 66 % 67 % Provision for uncompensated care 8 % 7 % 6 %
Schedule of Net Revenue Attributable to Medicaid, Medicare, Private Insurance and Self Pay as Percentage of Net Air Medical Independent Provider Model Revenues	Amounts attributable to Medicaid, Medicare, private insurance, and self-pay as a percentage of net Air Medical independent provider model revenues were as follows: Year Ended December 31, 2018 2017 2016 Insurance 71 % 72 % 72 % Medicare 20 % 18 % 18 % Medicaid 8 % 9 % 9 % Self-Pay 1 % 1 % 1 %
Schedule of Disaggregation of Revenue	The following table presents the Company’s revenues by segment disaggregated by type (in thousands): For the Year Ended December 31, 2018 2017 Service Revenue Oil & Gas $ 380,238 $ 298,398 Air Medical 257,132 257,273 Technical Services 37,053 23,874 Total Services $ 674,423 $ 579,545 Air Medical Revenue Traditional provider model $ 45,220 $ 44,147 Independent provider model 211,912 213,126 Total Air Medicals Revenues $ 257,132 $ 257,273
Schedule of Cash and Cash Equivalents	The following tables provide a reconciliation of cash, cash equivalents, and restricted cash reported within the consolidated balance sheets that total to the amounts shown in the statements of cash flows for the Company at December 31, 2018: Year Ended December 31, 2018 2017 2016 Cash and Cash Equivalents $ 50,874 $ 8,770 $ 2,596 Restricted Cash 7,690 — — Total Cash, Cash Equivalents and Restricted Cash $ 58,564 $ 8,770 $ 2,596
Schedule of Restricted Cash	The following tables provide a reconciliation of cash, cash equivalents, and restricted cash reported within the consolidated balance sheets that total to the amounts shown in the statements of cash flows for the Company at December 31, 2018: Year Ended December 31, 2018 2017 2016 Cash and Cash Equivalents $ 50,874 $ 8,770 $ 2,596 Restricted Cash 7,690 — — Total Cash, Cash Equivalents and Restricted Cash $ 58,564 $ 8,770 $ 2,596

Acquisition of Business (Tables

Acquisition of Business (Tables)	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
Schedule of Fair Value of Assets Acquired and Liabilities Assumed	The following amounts represent the fair value of assets acquired and liabilities assumed in the merger. Thousands of dollars Cash $ 4,142 Accounts receivable 27,819 Inventories 3,096 Fixed assets 43,689 Intangible assets: Noncompete agreements (weighted-average life of 5 years) 900 Customer relationships (weighted-average life of 15 years) 11,622 Tradenames (weighted-average life of 7 years) 4,201 Other assets 5,310 Accounts payable and accrued liabilities (25,272 ) Deferred taxes (1) (5,270 ) Other liabilities (750 ) Total identifiable net assets 69,487 Goodwill (2) 61,299 Total consideration transferred $ 130,786 (1) In connection with the acquisition accounting, PHI provided deferred taxes related to the estimated fair value adjustments for acquired intangible assets. (2) Goodwill is the excess of purchase price over fair market value of the net assets acquired under the acquisition method of accounting. The amount of goodwill that is deductible for income tax purposes is not significant.

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Schedule of Investments	Investments consisted of the following as of December 31, 2018 : Cost Basis Unrealized Gains Unrealized Losses Fair Value (Thousands of dollars) Investments: Money market mutual funds $ 26,308 $ — $ — $ 26,308 Deferred compensation plan assets included in other assets 772 — — 772 Total $ 27,080 $ — $ — $ 27,080 Investments consisted of the following as of December 31, 2017 : Cost Basis Unrealized Gains Unrealized Losses Fair Value (Thousands of dollars) Investments: Money market mutual funds $ 5,601 $ — $ — $ 5,601 U.S. government agencies 7,501 — (34 ) 7,467 Corporate bonds and notes 63,880 — (330 ) 63,550 Subtotal 76,982 — (364 ) 76,618 Deferred compensation plan assets included in other assets 2,685 — — 2,685 Total $ 79,667 $ — $ (364 ) $ 79,303
Debt Investments Classified by Contractual Maturity	The following table presents the cost and fair value of our debt investments based on maturities as of December 31, 2018 2017 Amortized Costs Fair Value Amortized Costs Fair Value (Thousands of dollars) Due in one year or less $ — $ — $ 31,348 $ 31,254 Due within two years — — 40,032 39,763 Total $ — $ — $ 71,380 $ 71,017
Average Coupon Rate Percentage and Average Days to Maturity of Debt	The following table presents the average coupon rate percentage and the average days to maturity of our debt investments as of December 31, 2018 2017 Average Coupon Rate (%) Average Days To Maturity Average Coupon Rate (%) Average Days To Maturity U.S. government agencies — 0 1.370 370 Corporate bonds and notes — 0 1.766 392
Investments in Continuous Unrealized Loss Position for Less Than Twelve Months	The following table presents the fair value and unrealized losses related to our investments that have been in a continuous unrealized loss position for less than twelve months as of December 31, 2018 2017 Fair Value Unrealized Losses Fair Value Unrealized Losses (Thousands of dollars) U.S. government agencies $ — $ — $ 5,472 $ (28 ) Corporate bonds and notes — — 44,069 (271 ) Total $ — $ — $ 49,541 $ (299 )
Investments in Continuous Unrealized Loss Position For Twelve Months Or More	The following table presents the fair value and unrealized losses related to our investments that have been in a continuous unrealized loss position for twelve months or more as of December 31, 2018 2017 Fair Value Unrealized Losses Fair Value Unrealized Losses (Thousands of dollars) U.S. government agencies $ — $ — $ 1,994 $ (6 ) Corporate bonds and notes — — 19,482 (59 ) Total $ — $ — $ 21,476 $ (65 )

Fair Value (Tables)

Fair Value (Tables)	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Summary of Valuation of Investments and Financial Instruments Pricing Levels	The following tables summarize the valuation of our investments and financial instruments by the above pricing levels as of the valuation dates listed: December 31, 2018 Total (Level 1) (Level 2) (Thousands of dollars) Investments: Money market mutual funds $ 26,308 $ 26,308 $ — Deferred compensation plan assets 772 772 Total $ 27,080 $ 27,080 $ — December 31, 2017 Total (Level 1) (Level 2) (Thousands of dollars) Investments: Money market mutual funds $ 5,601 $ 5,601 $ — U.S. government agencies 7,467 — 7,467 Corporate bonds and notes 63,550 — 63,550 76,618 5,601 71,017 Deferred compensation plan assets 2,685 2,685 — Total $ 79,303 $ 8,286 $ 71,017

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Summary of Company's Property and Equipment	The following table summarizes the Company’s property and equipment at December 31 of the following years: 2018 2017 (Thousands of dollars) Flight equipment $ 1,227,341 $ 1,225,205 Facility & improvements 67,784 64,316 Operating equipment 30,832 29,913 Data processing equipment 35,889 34,747 Vehicles 3,798 8,202 Medical equipment 8,710 8,354 Other 6,056 6,523 1,380,410 1,377,260 Less accumulated depreciation and amortization (477,925 ) (430,495 ) Property and equipment, net $ 902,485 $ 946,765

Other Assets (Tables)

Other Assets (Tables)	12 Months Ended
	Dec. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Schedule of Company's Other Assets	The following table summarizes the Company’s other assets at December 31 of the following years: 2018 2017 (Thousands of dollars) Deposits on future purchases of aircraft $ 501 $ 501 Investment in Variable Interest Entities 519 330 Investments (Officers’ Deferred Compensation Plan) 772 2,685 Deferred Cost 2,721 — Receivables / Deposits Long Term 12,187 4,875 Other 1,678 350 Total $ 18,378 $ 8,741

Accrued and Other Current Lia_2

Accrued and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2018
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued and other current liabilities as of December 31 consisted of the following: 2018 2017 (Thousands of dollars) Salaries & wages $ 9,130 $ 6,240 Incentive compensation 5,226 8,991 Income taxes 895 930 Interest 7,774 8,108 Vacation payable 8,838 7,619 Group medical 1,755 1,344 Transportations tax 301 971 Operating lease 658 710 Workers compensation 846 959 Other 9,869 5,978 Total accrued liabilities $ 45,292 $ 41,850

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Components of Long-term Debt	December 31, 2018 December 31, 2017 Principal Unamortized Debt Issuance Debt Cost Principal Unamortized Debt Issuance Debt Cost (Thousands of dollars) Senior Notes issued March 17, 2014, interest only payable semi-annually at 5.25%, maturing March 15, 2019. $ 500,000 $ 260 $ 500,000 $ 1,506 Revolving Credit Facility due March 7, 2019 with a group of commercial banks, interest payable at variable rates. — — 117,500 — Related Party Loan - Thirty Two L.L.C., interest payable quarterly at 6%, due September 28, 2020. 130,000 765 — — Total long-term debt. $ 630,000 $ 1,025 $ 617,500 $ 1,506
Summary of Annual Maturities of Long-term Debt	Listed below is information on our future annual maturities of long-term debt (in thousands): 2019 $ 500,000 2020 130,000 2021 — 2022 — 2023 — Thereafter — Total $ 630,000

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	For financial reporting purposes, (loss) earnings before income taxes includes the following components: Year Ended December 31, 2018 2017 2016 (Thousands of dollars) United States $ (95,590 ) $ (50,871 ) $ (25,604 ) Foreign (71,870 ) (570 ) (1,546 ) Total (167,460 ) (51,441 ) (27,149 )
Schedule of Income Tax Expense	The provision for income taxes for 2018, 2017, and 2016 consisted of the following: Year Ended December 31, 2018 2017 2016 (Thousands of dollars) U.S. Federal: Current $ — $ — $ — Deferred (21,061 ) (57,637 ) (5,488 ) (21,061 ) (57,637 ) (5,488 ) U.S. State: Current $ 392 $ 199 $ 427 Deferred $ (2,058 ) $ (717 ) $ 3,218 $ (1,666 ) $ (518 ) $ 3,645 Foreign: Current $ 2,371 $ 108 $ 1,374 Deferred $ (5,590 ) (926 ) — $ (3,219 ) $ (818 ) $ 1,374 Provision for income taxes $ (25,946 ) $ (58,973 ) $ (469 )
Schedule of Income Tax Expense as Percentage of Pre-Tax Earnings	Income tax expense as a percentage of pre-tax earnings varies from the effective Federal statutory rate of 21% as a result of the following: Year Ended Year Ended Year Ended (Thousands of dollars, except percentage amounts) Amount Tax Amount Tax Amount Tax Income taxes at statutory rate $ (35,167 ) 21.0 % $ (18,004 ) 35.0 % $ (9,502 ) 35.0 % Increase (decrease) in taxes resulting from: Valuation allowance on foreign tax credits 229 -0.1 % 6,145 -12.0 % 8,991 -33.0 % Valuation allowance on state net operating loss carryforwards 107 -0.1 % 868 -2.0 % 5,028 -19.0 % Valuation Allowance - Other 88 -0.1 % 1,353 -3.0 % — — % Goodwill impairment 17,729 -10.6 % — — % — — % Change in tax rate on deferred items (1,163 ) 0.7 % — — % (4,772 ) 18.0 % Tax reform – Impact of change in tax rate — — % (49,219 ) 96.0 % — — % State income taxes, net of federal benefit (1,774 ) 1.1 % (1,386 ) 3.0 % (1,384 ) 5.0 % Foreign income tax rate differential (6,245 ) 3.7 % Other items – net 250 -0.1 % 1,270 -2.0 % 1,170 -4.0 % Total $ (25,946 ) 15.5 % $ (58,973 ) 115.0 % $ (469 ) 2.0 %
Schedule of Tax Effects of Temporary Differences that Give Rise to Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities	The tax effects of significant items comprising our net deferred tax balance at December 31 are as follows: 2018 2017 (Thousands of dollars) Deferred tax assets: Deferred compensation $ 162 $ 626 Foreign tax credits 18,826 19,453 Vacation and bonus accrual 2,170 3,936 Inventory valuation 6,686 4,954 Interest disallowance 5,497 — Rental accrual 601 747 Hurricane relief credit 1,308 1,255 Stock-based compensation 2,118 988 Other 2,653 2,235 Net operating losses 95,307 82,044 Total deferred tax assets 135,328 116,238 Valuation allowance – state NOL carryforwards (6,105 ) (5,998 ) Valuation allowance – tax credit carryforwards (16,127 ) (16,537 ) Valuation allowance – foreign NOL carryforwards (186 ) (98 ) Total deferred tax assets, net 112,910 93,605 Deferred tax liabilities: Tax depreciation in excess of book depreciation (165,193 ) (171,116 ) Other (1,951 ) (5,185 ) Total deferred tax liabilities (167,144 ) (176,301 ) Net deferred tax liabilities $ (54,234 ) $ (82,696 ) Deferred tax assets – short-term — — Deferred tax assets – long-term 4,944 3,309 Deferred tax liability – long-term (59,178 ) (86,005 ) Net deferred tax liabilities $ (54,234 ) $ (82,696 )

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Components of Basic and Diluted Earnings Per Share	The components of basic and diluted earnings per share for the years ended December 31, are as follows: 2018 2017 2016 (in thousands) Weighted average outstanding shares of common stock, basic 15,818 15,762 15,663 Dilutive effect of unvested restricted stock units — — — Weighted average outstanding shares of common stock, diluted 15,818 15,762 15,663

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Summary of Activity for Non-voting Time-vested Restricted Stock	The following table summarizes the activity for non-voting time-vested restricted stock units granted to non-employee directors for the year ended December 31, 2018 . Share Units Weighted Average Grant-Date Fair Value Remaining Average Contractual Life (in years) Aggregate Value (in thousands) Outstanding at January 1, 2018 19,680 $ 14.94 2.71 $ 292 Granted 15,225 8.77 Forfeited — — Vested and released to participants (4,452 ) 21.42 Outstanding at December 31, 2018 30,453 $ 10.99 2.19 $ 335
Non-Voting Time-Vested Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Summary of Activity for Non-voting Time-vested Restricted Stock	The following table summarizes the activity for non-voting time-vested restricted stock units granted to employees for the year ended December 31, 2018 . Share Units Weighted Average Grant-Date Fair Value Remaining Average Contractual Life ( in years) Aggregate Value ( in thousands) Outstanding at January 1, 2018 534,711 $ 12.80 2.26 $ 6,844 Granted 366,055 12.55 Forfeited (6,755 ) 19.86 Vested and released to participants (28,723 ) 29.45 Outstanding at December 31, 2018 865,288 $ 11.73 1.88 $ 10,146
Non-Voting Performance Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Summary of Activity for Non-voting Time-vested Restricted Stock	The following table summarizes the activity for non-voting performance-based restricted stock units for the year ended December 31, 2018 . Share Units Weighted Average Grant-Date Fair Value Remaining Average Contractual Life ( in years) Aggregate Value ( in thousands) Outstanding at January 1, 2018 818,150 $ 18.60 1.20 $ 15,218 Granted 448,012 12.54 Forfeited (165,397 ) 31.33 Vested and released to participants — — Outstanding at December 31, 2018 1,100,765 $ 13.23 1.99 $ 14,564

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Summary of Rental Expense Incurred under Leases	Rental expense incurred under these leases consisted of the following: Year Ended Year Ended Year Ended (Thousands of dollars) Aircraft $ 35,740 $ 39,815 $ 44,130 Other 11,718 9,504 9,451 Total $ 47,458 $ 49,319 $ 53,581
Summary of Remaining Aggregate Lease Commitments Under Operating Leases Having Initial Non-Cancelable Terms in Excess of One Year	The table includes renewal periods on the principal operating facility lease. Aircraft Other Total (Thousands of dollars) 2019 $ 29,705 $ 6,765 $ 36,470 2020 27,406 5,403 32,809 2021 27,272 3,855 31,127 2022 26,758 2,018 28,776 2023 19,170 516 19,686 Thereafter 9,907 761 10,668 $ 140,218 $ 19,318 $ 159,536

Business Segments and Geograp_2

Business Segments and Geographic Areas (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Schedule of Accounts Receivable and Revenue by Major Customers by Reporting Segments	The customers, individually or considered as a group under common ownership, which accounted for greater than 10% of accounts receivable or 10% of operating revenues during the periods reflected were as follows: Accounts Receivable December 31, Operating Revenues Years Ended December 31, 2018 2017 2018 2017 2016 Oil and Gas segment: Customer A 15 % 11 % 17 % 14 % 14 % Customer B 5 % 5 % 7 % 9 % 10 % Air Medical & Technical Services segments: Customer C — % 10 % — % — % 5 %
Schedule of Profit or Loss and Assets of Each of Company's Reportable Segments	The following table shows information about the profit or loss and assets of each of the Company’s reportable segments for the years ended December 31, 2018 , 2017 , and 2016 . The information contains certain allocations, including allocations of depreciation, rents, insurance, and overhead expenses that the Company deems reasonable and appropriate for the evaluation of its results of operations. The Company does not allocate gains on dispositions of property and equipment, other income, interest expense, income taxes, and corporate selling, general, and administrative expenses to its segments. Where applicable, the tables present the unallocated amounts to reconcile the totals to the Company’s consolidated financial statements. Corporate assets are principally cash, short-term investments, other assets, and certain property and equipment. Year Ended December 31, 2018 2017 2016 (Thousands of dollars) Segment operating revenues Oil and Gas $ 380,238 $ 298,398 $ 324,129 Air Medical 257,132 257,273 281,868 Technical Services 37,053 23,874 28,101 Total operating revenues 674,423 579,545 634,098 Segment direct expenses Oil and Gas (1) 371,930 321,272 344,640 Air Medical 230,840 208,987 227,877 Technical Services 28,849 16,825 19,882 Total segment direct expenses 631,619 547,084 592,399 Segment selling, general and administrative expenses Oil and Gas 18,485 5,899 6,739 Air Medical 13,833 12,442 10,968 Technical Services 1,418 1,405 1,101 Total segment selling, general and administrative expenses 33,736 19,746 18,808 Total segment expenses 665,355 566,830 611,207 Net segment (loss) profit Oil and Gas (10,177 ) (28,773 ) (27,250 ) Air Medical 12,459 35,844 43,023 Technical Services 6,786 5,644 7,118 Total net segment profit 9,068 12,715 22,891 Impairments of assets (109,024 ) (368 ) (407 ) Other, net (2) (574 ) 2,466 6,621 Unallocated selling, general and administrative expenses (32,949 ) (34,071 ) (25,610 ) Interest expense (33,981 ) (32,183 ) (30,644 ) (Loss) earnings before income taxes $ (167,460 ) $ (51,441 ) $ (27,149 ) (1) Includes equity in gain/loss of unconsolidated affiliate. (2) Includes gain/loss on disposition of property and equipment and other income.
Summary of Gains on Disposition of Property and Equipment and Other Income	Year Ended December 31, 2018 2017 2016 (Thousands of dollars) Expenditures for Long-Lived Assets Oil and Gas $ 34,171 $ 52,525 $ 59,278 Air Medical 7,268 5,696 22,429 Corporate 1,469 257 1,164 Total $ 42,908 $ 58,478 $ 82,871 As of or for Year Ended December 31, 2018 2017 2016 (Thousands of dollars) Depreciation and Amortization Oil and Gas $ 47,723 $ 39,655 $ 40,170 Air Medical 22,606 20,413 19,716 Technical Services 499 581 564 Corporate 8,426 7,378 5,293 Total 79,254 68,027 65,743 Assets Oil and Gas $ 594,331 $ 722,734 Air Medical 387,701 372,646 Technical Services 5,515 5,979 Corporate 274,679 300,487 Total 1,262,226 1,401,846
Summary of Company's Revenues from External Customers and Long-Lived Assets, by Geographical Areas	The following table presents the Company’s revenues from external customers attributed to operations in the United States and foreign areas and long-lived assets in the United States and foreign areas. As of or for Year Ended December 31, 2018 2017 2016 (Thousands of dollars) Operating Revenues: United States $ 516,717 $ 530,115 $ 579,300 International 157,706 49,430 54,798 Total $ 674,423 $ 579,545 $ 634,098 Long-Lived Assets: United States $ 552,350 $ 601,530 International 350,135 345,235 Total $ 902,485 $ 946,765

Quarterly Financial Data (Una_2

Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Summary of Condensed Quarterly Results of Operations	The condensed quarterly results of operations for the years ended December 31, 2018 and 2017 (in thousands of dollars, except per share data) were as follows: Quarter Ended March 31, June 30, September 30, December 31, 2018 2018 2018 2018 (Thousands of dollars, except per share data) Operating revenues, net $ 160,370 $ 169,243 $ 168,787 $ 176,023 (Loss) gain on disposition of assets, net 879 (171 ) — 45 (Loss) earnings before income taxes (21,473 ) (8,777 ) (14,062 ) (123,148 ) Net (loss) earnings (16,983 ) (7,093 ) (11,531 ) (105,907 ) Net (loss) earnings per share Basic (1.07 ) (0.45 ) (0.73 ) (6.70 ) Diluted (1.07 ) (0.45 ) (0.73 ) (6.70 ) Quarter Ended March 31, June 30, September 30, December 31, 2017 2017 2017 2017 (Thousands of dollars, except per share data) Operating revenues, net $ 134,618 $ 146,424 $ 150,167 $ 148,336 Gain (loss) on disposition of assets, net — 7 4 287 Earnings before income taxes (23,073 ) (3,150 ) (4,899 ) (20,319 ) Net earnings (15,248 ) (3,273 ) (3,277 ) 29,330 Net earnings per share Basic (0.97 ) (0.21 ) (0.21 ) 1.87 Diluted (0.97 ) (0.21 ) (0.21 ) 1.87

Condensed Consolidating Finan_2

Condensed Consolidating Financial Information - Guarantor Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Condensed Consolidating Balance Sheets	PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS (Thousands of dollars) December 31, 2018 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated ASSETS Current Assets: Cash $ 39,091 $ 1,259 $ 10,524 $ — $ 50,874 Short-term investments 14,232 — — — 14,232 Accounts receivable – net 64,416 93,060 28,812 (3,823 ) 182,465 Intercompany receivable — 91,468 — (91,468 ) — Inventories of spare parts – net 43,933 9,577 3,188 — 56,698 Prepaid expenses 7,295 2,520 1,604 — 11,419 Deferred income taxes — — — — — Income taxes receivable 394 556 — — 950 Total current assets 169,361 198,440 44,128 (95,291 ) 316,638 Investment in subsidiaries and others 471,790 — — (471,790 ) — Property and equipment – net 576,763 287,375 38,347 — 902,485 Restricted cash and investments 19,781 — — — 19,781 Other assets 17,179 1,199 — — $ 18,378 Deferred income tax — — 4,944 — 4,944 Total assets $ 1,254,874 $ 487,014 $ 87,419 $ (567,081 ) $ 1,262,226 LIABILITIES AND SHAREHOLDERS’ EQUITY Current Liabilities: Senior Notes issued March 17, 2014 $ 499,740 $ — $ — $ — $ 499,740 Accounts payable $ 44,089 $ 4,587 $ 5,452 $ (3,839 ) $ 50,289 Accrued and other current liabilities 25,158 12,335 7,799 — 45,292 Intercompany payable 74,336 — 17,116 (91,452 ) — Total current liabilities 643,323 16,922 30,367 (95,291 ) 595,321 Long-term debt 129,235 — — — 129,235 Deferred income taxes and other long-term liabilities 4,934 58,752 551 — 64,237 Shareholders’ Equity: Common stock and paid-in capital 315,898 77,951 132,650 (210,601 ) 315,898 Accumulated other comprehensive loss (3 ) — (3,949 ) — (3,952 ) Retained earnings 161,487 333,389 (72,200 ) (261,189 ) 161,487 Total shareholders’ equity 477,382 411,340 56,501 (471,790 ) 473,433 Total liabilities and shareholders’ equity $ 1,254,874 $ 487,014 $ 87,419 $ (567,081 ) $ 1,262,226 PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS (Thousands of dollars) December 31, 2017 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated ASSETS Current Assets: Cash $ 47 $ 1,072 $ 7,651 $ — $ 8,770 Short-term investments 64,237 — — — 64,237 Accounts receivable – net 90,077 74,886 38,020 (17,004 ) 185,979 Intercompany receivable — 126,366 — (126,366 ) — Inventories of spare parts – net 68,737 9,049 3,095 — 80,881 Prepaid expenses 8,348 1,898 1,229 — 11,475 Deferred income taxes — — — — — Income taxes receivable 345 9 917 — 1,271 Total current assets 231,791 213,280 50,912 (143,370 ) 352,613 Investment in subsidiaries 529,222 — — (529,222 ) — Property and equipment – net 617,488 284,984 44,293 — 946,765 Restricted investments 12,382 — 14 — 12,396 Other assets 7,833 908 — — 8,741 Deferred income tax — — 3,309 — 3,309 Goodwill — — 61,299 — 61,299 Intangible assets — — 16,723 — 16,723 Total assets $ 1,398,716 $ 499,172 $ 176,550 $ (672,592 ) $ 1,401,846 LIABILITIES AND SHAREHOLDERS’ EQUITY Current Liabilities: Accounts payable $ 28,130 $ 4,636 $ 21,425 $ (17,005 ) $ 37,186 Accrued liabilities 23,147 10,577 8,126 — 41,850 Intercompany payable 113,387 — 12,978 (126,365 ) — Total current liabilities 164,664 15,213 42,529 (143,370 ) 79,036 Long-term debt 615,994 — — — 615,994 Deferred income taxes and other long-term liabilities 5,404 84,300 4,458 — 94,162 Shareholders’ Equity: Common stock and paid-in capital 309,933 77,951 133,296 (211,247 ) 309,933 Accumulated other comprehensive loss (280 ) — — — (280 ) Retained earnings 303,001 321,708 (3,733 ) (317,975 ) 303,001 Total shareholders’ equity 612,654 399,659 129,563 (529,222 ) 612,654 Total liabilities and shareholders’ equity $ 1,398,716 $ 499,172 $ 176,550 $ (672,592 ) $ 1,401,846
Condensed Consolidating Statements of Operations	PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Thousands of dollars) For the year ended December 31, 2018 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Operating revenues, net $ 329,268 $ 263,679 $ 109,882 $ (28,406 ) $ 674,423 Expenses: Direct expenses 331,785 236,366 92,062 (28,406 ) 631,807 Selling, general, and administrative expenses 40,715 13,834 12,154 (18 ) 66,685 Total operating expenses 372,500 250,200 104,216 (28,424 ) 698,492 Loss on disposition of assets, net 774 — (21 ) — 753 Impairment of assets 31,824 — 77,200 — 109,024 Equity in loss of unconsolidated affiliate (188 ) — — — (188 ) Operating (loss) income (75,642 ) 13,479 (71,513 ) 18 (133,658 ) Equity in net earnings of consolidated subsidiaries 56,786 — — (56,786 ) — Interest expense 33,964 13 4 — 33,981 Other income, net (547 ) — 350 18 (179 ) 90,203 13 354 (56,768 ) 33,802 (Loss) earnings before income taxes (165,845 ) 13,466 (71,867 ) 56,786 (167,460 ) Income tax (benefit) expense (24,331 ) 1,785 (3,400 ) — (25,946 ) Net earnings (loss) $ (141,514 ) $ 11,681 $ (68,467 ) $ 56,786 $ (141,514 ) For the year ended December 31, 2017 Parent Non- Company Guarantor Guarantor Only (issuer) Subsidiaries Subsidiaries Eliminations Consolidated Operating revenues, net $ 310,449 $ 262,229 $ 23,871 $ (17,004 ) $ 579,545 Expenses: Direct expenses 326,152 212,691 24,860 (17,004 ) 546,699 Selling, general, and administrative expenses 41,134 12,462 221 — 53,817 Total operating expenses 367,286 225,153 25,081 (17,004 ) 600,516 Gain on disposition of assets, net 300 (2 ) — — 298 Impairment of assets 368 — — — 368 Equity in profit of unconsolidated affiliate 1,021 — (636 ) — 385 Operating (loss) income (58,526 ) 37,078 (574 ) — (22,022 ) Equity in net earnings of consolidated subsidiaries (38,553 ) — — 38,553 — Interest expense 32,161 22 — — 32,183 Other income, net (2,757 ) (2 ) (5 ) — (2,764 ) (9,149 ) 20 (5 ) 38,553 29,419 (Loss) earnings before income taxes (49,377 ) 37,058 (569 ) (38,553 ) (51,441 ) Income tax (benefit) expense (56,909 ) (1,138 ) (926 ) — (58,973 ) Net (loss) earnings $ 7,532 $ 38,196 $ 357 $ (38,553 ) $ 7,532 PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Thousands of dollars) For the year ended December 31, 2016 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Operating revenues, net $ 339,829 $ 293,329 $ 940 $ — $ 634,098 Expenses: Direct expenses 347,532 237,635 7,383 — 592,550 Selling, general, and administrative expenses 32,911 10,984 541 (18 ) 44,418 Total operating expenses 380,443 248,619 7,924 (18 ) 636,968 Loss on disposition of assets, net (3,350 ) — — (3,350 ) Equity in loss of unconsolidated affiliate (151 ) — — (151 ) Operating income (37,520 ) 44,710 (6,984 ) 18 224 Equity in net earnings of consolidated subsidiaries (22,182 ) — — 22,182 — Interest expense 30,585 46 13 — 30,644 Other income, net (3,284 ) (5 ) — 18 (3,271 ) 5,119 41 13 22,200 27,373 Earnings before income taxes (42,639 ) 44,669 (6,997 ) (22,182 ) (27,149 ) Income tax (benefit) expense (15,959 ) 15,490 — — (469 ) Net earnings $ (26,680 ) $ 29,179 $ (6,997 ) $ (22,182 ) $ (26,680 )
Condensed Consolidated Statements of Comprehensive Income	PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (Thousands of dollars) For the year ended December 31, 2018 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Net (loss) earnings $ (141,514 ) $ 11,681 $ (68,467 ) $ 56,786 $ (141,514 ) Unrealized gain on short-term investments 364 — — — 364 Changes in pension plan assets and benefit obligations (1 ) — — — (1 ) Tax effect (85 ) — — — (85 ) Currency translation adjustment — — (3,950 ) $ — (3,950 ) Total comprehensive income $ (141,236 ) $ 11,681 $ (72,417 ) $ 56,786 $ (145,186 ) For the year ended December 31, 2017 Parent Non- Company Guarantor Guarantor Only Subsidiaries Subsidiaries Eliminations Consolidated Net (loss) earnings $ 7,532 $ 38,196 $ 357 $ (38,553 ) $ 7,532 Unrealized gain on short-term investments 310 — — — 310 Changes in pension plan assets and benefit obligations (3 ) — — — (3 ) Tax effect (109 ) — — — (109 ) Total comprehensive (loss) income $ 7,730 $ 38,196 $ 357 $ (38,553 ) $ 7,730 For the year ended December 31, 2016 Parent Non- Company Guarantor Guarantor Only Subsidiaries Subsidiaries Eliminations Consolidated Net earnings $ (26,680 ) $ 29,179 $ (6,997 ) $ (22,182 ) $ (26,680 ) Unrealized loss on short-term investments 241 — — — 241 Other unrealized gain — — — — — Changes in pension plan assets and benefit obligations (39 ) — — — (39 ) Tax effect (113 ) — — — (113 ) Total comprehensive income $ (26,591 ) $ 29,179 $ (6,997 ) $ (22,182 ) $ (26,591 )
Condensed Consolidating Statements of Cash Flows	PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (Thousands of dollars) For the year ended December 31, 2018 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Net cash (used in) provided by operating activities $ 24,123 $ (16,952 ) $ 10,477 $ — $ 17,648 Investing activities: Purchase of property and equipment (40,865 ) — (2,311 ) — (43,176 ) Proceeds from asset dispositions 14,245 — — — 14,245 Purchase of short-term investments (284,481 ) — — — (284,481 ) Proceeds from sale of short-term investments 334,488 — — — 334,488 Loan to unconsolidated affiliate (274 ) — — — (274 ) Net cash provided by (used in) investing activities 23,113 — (2,311 ) — 20,802 Financing activities: Debt issuance costs (874 ) — — — (874 ) Repurchase of common stock (106 ) — — — (106 ) Proceeds on line of credit 34,295 — — — 34,295 Payments on line of credit (151,795 ) — — — (151,795 ) Proceeds from term loan 130,000 — — — 130,000 Due to/from affiliate, net (12,022 ) 17,139 (5,117 ) — — Net cash (used in) provided by financing activities (502 ) 17,139 (5,117 ) — 11,520 Effect of exchange rate changes on cash and cash equivalent — — (176 ) — (176 ) Increase (decrease) in cash, cash equivalents and restricted cash 46,734 187 2,873 — 49,794 Cash, cash equivalents and restricted cash at beginning of period 47 1,072 7,651 — 8,770 Cash, cash equivalents and restricted cash at end of period $ 46,781 $ 1,259 $ 10,524 $ — $ 58,564 (1) Net of the effect of business acquisitions. PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (Thousands of dollars) For the year ended December 31, 2017 Parent Guarantor Non-Guarantor Subsidiaries Eliminations Consolidated Net cash (used in) by operating activities $ (62,581 ) $ 40,628 $ 2,850 $ — $ (19,103 ) Investing activities: Purchase of property and equipment (56,757 ) — — — (56,757 ) Proceeds from asset dispositions 1,296 — — — 1,296 Purchase of short-term investments (637,980 ) — — — (637,980 ) Proceeds from sale of short-term investments 862,942 — — — 862,942 Payments of deposits on aircraft — — — — — Loan to third party (824 ) — — — (824 ) Business acquisitions net of cash acquired (130,788 ) — 4,144 — (126,644 ) Net cash used in investing activities 37,889 — 4,144 — 42,033 Financing activities: Repurchase of common stock (256 ) — — — (256 ) Proceeds on line of credit 152,150 — — — 152,150 Payments on line of credit (168,650 ) — — — (168,650 ) Due to/from affiliate, net 41,459 (41,656 ) 197 — — Net cash provided by (used in) financing activities 24,703 (41,656 ) 197 — (16,756 ) Increase (decrease) in cash, cash equivalents and restricted cash 11 (1,028 ) 7,191 — 6,174 Cash, cash equivalents and restricted cash at beginning of period 36 2,100 460 — 2,596 Cash, cash equivalents and restricted cash at end of period $ 47 $ 1,072 $ 7,651 $ — $ 8,770 PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (Thousands of dollars) For the year ended December 31, 2016 Parent Guarantor Non- Eliminations Consolidated Net cash provided by operating activities $ (46,738 ) $ 52,873 $ (6,699 ) $ — $ (564 ) Investing activities: Purchase of property and equipment (81,484 ) — (358 ) — (81,842 ) Proceeds from asset dispositions 14,983 — — — 14,983 Purchase of short-term investments (321,453 ) — — — (321,453 ) Proceeds from sale of short-term investments 316,543 — — — 316,543 Payments of deposits on aircraft (2,249 ) — — — (2,249 ) Loan to unconsolidated affiliate (1,200 ) — — — (1,200 ) Net cash used in investing activities (74,860 ) — (358 ) — (75,218 ) Financing activities: Repurchase of common stock (529 ) — — — (529 ) Proceeds on line of credit 264,700 — — — 264,700 Payments on line of credit (188,200 ) — — — (188,200 ) Due to/from affiliate, net 45,617 (52,445 ) 6,828 — — Net cash provided by (used in) financing activities 121,588 (52,445 ) 6,828 — 75,971 Decrease in cash (10 ) 428 (229 ) — 189 Cash, beginning of year 46 1,672 689 — 2,407 Cash, end of year $ 36 $ 2,100 $ 460 $ — $ 2,596

Asset Impairment (Tables)

Asset Impairment (Tables)	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule Of Asset Impairment Charges	The impairment charges were recorded in Impairment of assets in the consolidated statement of operations. See Note 1 for additional information. Year Ended December 31, 2018 2017 2016 Goodwill $ 61,643 $ — $ — Intangible assets 15,557 — — Aircraft and related inventory 31,824 368 407 Total $ 109,024 $ 368 $ 407

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended	12 Months Ended
	Dec. 31, 2018USD ($)	Dec. 31, 2018USD ($)Aircraft	Dec. 31, 2017USD ($)Aircraft	Dec. 31, 2016USD ($)Aircraft	Mar. 31, 2019USD ($)	Mar. 13, 2019USD ($)	Mar. 17, 2014
Summary Of Significant Accounting Policies [Line Items]
Percentage of stock owned by CEO		70.90%
Principal	$ 630,000,000	$ 630,000,000	$ 617,500,000
Letters of credit outstanding under the facility	19,800,000	19,800,000	19,600,000
Aggregate lease commitments	159,536,000	$ 159,536,000
Maturities Period of liquid investments		Three months or less
Valuation reserves related to obsolescence and slow moving inventory	17,900,000	$ 17,900,000	20,900,000
Impairments of assets		$ 109,024,000	368,000	$ 407,000
Goodwill impairment, discounted cash flow method (percent)		80.00%
Goodwill impairment, public company guideline method (percent)		20.00%
Accumulatec impairment of goodwill	61,600,000	$ 61,600,000
Intangible assets	15,500,000	15,557,000	0	0
Insurance retention per claim		250,000
Accrued liabilities related to health care claims	1,800,000	1,800,000	1,300,000
Amount deductible per incident		500,000
Accrued expense related to workers compensation claims	1,900,000	1,900,000	2,900,000
Amounts paid to offshore insurance captive		$ 300,000	500,000
Typical contract length		30 days
Allowance for contractual discounts against outstanding accounts receivable	123,800,000	$ 123,800,000	117,800,000	111,900,000
Allowance for uncompensated care against outstanding accounts receivable	51,900,000	51,900,000	52,500,000	46,300,000
Value of uncompensated care services	7,200,000	7,200,000	7,100,000	8,800,000
Estimated cost of providing charity services		$ 1,700,000	1,600,000	1,900,000
Percentage of reserved category of self pay		100.00%
Provisionally recognized tax benefit			(49,200,000)
Tax expense with respect to GILTI		$ 0
Allowance for doubtful accounts	6,100,000	$ 6,100,000	7,200,000
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable invoice term		60 days
Contract termination notice period		180 days
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable invoice term		30 days
Contract termination notice period		30 days
Light Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Impairments of assets		$ 23,200,000	400,000	400,000
Oil and Gas [Member]
Summary Of Significant Accounting Policies [Line Items]
Cash proceeds		14,200,000	1,300,000	15,000,000
Gain (loss) on disposal of assets		(800,000)	(300,000)	$ 3,300,000
Accounts receivable	74,100,000	$ 74,100,000	$ 86,900,000
Oil and Gas [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Typical contract length		7 years
Oil and Gas [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Typical contract length		1 year
Oil and Gas [Member] | Heavy Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of aircraft sold | Aircraft		1
Number of aircraft impaired | Aircraft		1
Oil and Gas [Member] | Light Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of aircraft sold | Aircraft		1		12
Number of aircraft impaired | Aircraft		2
Carrying value of aircraft	109,600,000	$ 109,600,000
Oil and Gas [Member] | Light Aircraft [Member] | Fair Value, Inputs, Level 3 [Member]
Summary Of Significant Accounting Policies [Line Items]
Market value of aircraft	85,200,000	$ 85,200,000
Oil and Gas [Member] | Medium Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of aircraft sold | Aircraft		3	6	11
Number of aircraft impaired | Aircraft		17
Oil and Gas [Member] | Fixed Wing Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of aircraft sold | Aircraft			1
Air Medical and Technical Services [Member]
Summary Of Significant Accounting Policies [Line Items]
Threshold customer percentage for operating revenue not exceeded during the year (percent)		2.00%	2.00%	2.00%
Air Medical [Member]
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable	90,200,000	$ 90,200,000	$ 76,600,000
Technical Services [Member]
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable	$ 4,100,000	$ 4,100,000	$ 4,700,000
Aircraft [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Salvage value of aircraft	54.00%	54.00%
Aircraft [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Salvage value of aircraft	25.00%	25.00%
Flight Equipment [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life		15 years
Flight Equipment [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life		5 years
Other Equipment [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life		10 years
Other Equipment [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life		3 years
Leasehold Improvements [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life		10 years
Leasehold Improvements [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life		6 years
Accounts Receivable [Member] | Customer Concentration Risk [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage owed by an overseas customer (percent)		10.70%
Two Largest Customers [Member] | Oil and Gas [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of consolidated operating revenues		24.00%	23.00%	24.00%
Percentage of trade receivables	20.00%	20.00%	16.00%
One Customer [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of trade receivables	13.50%	13.50%	10.00%
One Customer [Member] | Air Medical [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of consolidated operating revenues			5.00%
Scenario, Forecast [Member] | Accounting Standards Update 2016-02 [Member]
Summary Of Significant Accounting Policies [Line Items]
Lease liabilities					$ 172,900,000
Right-of-use assets					$ 172,100,000
5.25% Senior Notes due March 15, 2019 [Member] | Senior Notes [Member]
Summary Of Significant Accounting Policies [Line Items]
Principal	$ 500,000,000	$ 500,000,000	$ 500,000,000
Interest rate on Senior Notes	5.25%	5.25%					5.25%
6% Related Party Term Loan [Member] | Medium-term Notes [Member]
Summary Of Significant Accounting Policies [Line Items]
Principal	$ 130,000,000	$ 130,000,000
Interest rate on Senior Notes	6.00%	6.00%
Maturity term of loan		2 years
Subsequent Event [Member] | Medium-term Notes [Member]
Summary Of Significant Accounting Policies [Line Items]
Principal						$ 70,000,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Provisions for Contractual Discounts and Uncompensated Care Applied to Air Medical Trade Receivables Expressed as Percentage of Total Segment Accounts Receivable (Detail) - Air Medical [Member]	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Provisions For Contractual Discounts And Estimated Uncompensated Care [Line Items]
Allowance for contractual discounts	67.00%	66.00%	67.00%
Trade Accounts Receivable [Member]
Provisions For Contractual Discounts And Estimated Uncompensated Care [Line Items]
Allowance for contractual discounts	51.00%	53.00%
Allowance for uncompensated care	22.00%	24.00%

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Intangible Assets (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)
Finite-Lived Intangible Assets [Line Items]
Gross amount	$ 16,723
Accumulated amortization	(1,166)
Impairment of assets	(15,557)
Net balance	$ 0
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets	15 years
Gross amount	$ 11,622
Accumulated amortization	(581)
Impairment of assets	(11,041)
Net balance	$ 0
Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets	5 years
Gross amount	$ 900
Accumulated amortization	(135)
Impairment of assets	(765)
Net balance	$ 0
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets	7 years
Gross amount	$ 4,201
Accumulated amortization	(450)
Impairment of assets	(3,751)
Net balance	$ 0

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Schedule of Provisions for Contractual Discounts and Estimated Uncompensated Care Applied to Air Medical Revenues Expressed as Percentage of Total Independent Provider Model Billings (Detail) - Air Medical [Member]	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Provisions For Contractual Discounts And Estimated Uncompensated Care [Line Items]
Provision for contractual discounts	67.00%	66.00%	67.00%
Provision for uncompensated care	8.00%	7.00%	6.00%

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Schedule of Net Revenue Attributable to Medicaid, Medicare, Private Insurance and Self Pay as Percentage of Net Air Medical Independent Provider Model Revenues (Detail) - Air Medical [Member]	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Insurance [Member]
Segment Reporting Information [Line Items]
Percentage of net Air Medical revenues	71.00%	72.00%	72.00%
Medicare [Member]
Segment Reporting Information [Line Items]
Percentage of net Air Medical revenues	20.00%	18.00%	18.00%
Medicaid [Member]
Segment Reporting Information [Line Items]
Percentage of net Air Medical revenues	8.00%	9.00%	9.00%
Self Pay [Member]
Segment Reporting Information [Line Items]
Percentage of net Air Medical revenues	1.00%	1.00%	1.00%

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Disaggregated Revenue by Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Operating revenues, net	$ 176,023	$ 168,787	$ 169,243	$ 160,370	$ 148,336	$ 150,167	$ 146,424	$ 134,618	$ 674,423	$ 579,545	$ 634,098
Operating Segments [Member]
Disaggregation of Revenue [Line Items]
Operating revenues, net									674,423	579,545	634,098
Operating Segments [Member] | Oil and Gas [Member]
Disaggregation of Revenue [Line Items]
Operating revenues, net									380,238	298,398	324,129
Operating Segments [Member] | Air Medical [Member]
Disaggregation of Revenue [Line Items]
Operating revenues, net									257,132	257,273	281,868
Operating Segments [Member] | Technical Services [Member]
Disaggregation of Revenue [Line Items]
Operating revenues, net									37,053	23,874	$ 28,101
Traditional Provider Model [Member] | Operating Segments [Member] | Air Medical [Member]
Disaggregation of Revenue [Line Items]
Operating revenues, net									45,220	44,147
Independent Provider Model [Member] | Operating Segments [Member] | Air Medical [Member]
Disaggregation of Revenue [Line Items]
Operating revenues, net									$ 211,912	$ 213,126

Summary of Significant Accou_10

Summary of Significant Accounting Policies - New Accounting Pronouncements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred income taxes	$ 59,178	$ 86,005
Income tax expense	$ (25,946)	(58,973)	$ (469)
Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred income taxes		1,000
Income tax expense		$ 900
Retained Earnings [Member] | Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment				$ 1,000

Summary of Significant Accou_11

Summary of Significant Accounting Policies - Summary of Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Cash and Cash Equivalents	$ 50,874	$ 8,770	$ 2,596	$ 2,407
Restricted Cash	7,690	0	0
Total Cash, Cash Equivalents and Restricted Cash	$ 58,564	$ 8,770	$ 2,596	$ 2,407

Acquisition of Business (Detail

Acquisition of Business (Details) $ in Thousands, $ in Millions	Dec. 29, 2017CAD ($)	Dec. 29, 2017USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Business Acquisition [Line Items]
Aggregate principal amount of term loans provided			$ 0	$ 824	$ 0
Goodwill		$ 61,299	0	61,299
Cumulative merger-related transaction costs				2,300
Purchaser [Member]
Business Acquisition [Line Items]
Aggregate principal amount of term loans provided	$ 167.5	$ 131,600
Loans receivable expected to be repaid prior to December 31, 2019			$ 800
Oil and Gas [Member]
Business Acquisition [Line Items]
Goodwill				$ 61,000

Acquisition of Business - Asset

Acquisition of Business - Assets acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Dec. 29, 2017	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Cash	$ 4,142
Accounts receivable	27,819
Inventories	3,096
Fixed assets	43,689
Intangible assets:
Other assets	5,310
Accounts payable and accrued liabilities	(25,272)
Deferred taxes	(5,270)
Other liabilities	(750)
Total identifiable net assets	69,487
Goodwill	61,299	$ 0	$ 61,299
Total consideration transferred	130,786
Noncompete Agreements [Member]
Intangible assets:
Intangible assets	$ 900
Weighted average useful life of intangible assets	5 years
Customer Relationships [Member]
Intangible assets:
Intangible assets	$ 11,622
Weighted average useful life of intangible assets	15 years
Trade Names [Member]
Intangible assets:
Intangible assets	$ 4,201
Weighted average useful life of intangible assets	7 years

Investments - Additional Inform

Investments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Proceeds from sales of short term investments	$ 334,488	$ 862,942	$ 316,543
Restricted cash and investments	$ 19,781	$ 12,396

Investments - Components of Inv

Investments - Components of Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Total, Amortized Costs	$ 27,080	$ 79,667
Unrealized Gains	0	0
Unrealized Losses	0	(364)
Fair Value	27,080	79,303
Deferred Compensation Plan Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Total, Amortized Costs	772	2,685
Fair Value	772	2,685
Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Total, Amortized Costs		76,982
Unrealized Gains		0
Unrealized Losses		(364)
Fair Value		76,618
Money Market Mutual Funds [Member]
Debt Securities, Available-for-sale [Line Items]
Total, Amortized Costs	26,308	5,601
Fair Value	$ 26,308	5,601
US Government Agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Total, Amortized Costs		7,501
Unrealized Losses		(34)
Fair Value		7,467
Corporate Bonds and Notes [Member]
Debt Securities, Available-for-sale [Line Items]
Total, Amortized Costs		63,880
Unrealized Gains		0
Unrealized Losses		(330)
Fair Value		$ 63,550

Investments - Cost and Fair Val

Investments - Cost and Fair Value of Debt Investments Based on Maturities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Available-for-sale Securities, Debt Maturities [Abstract]
Due in one year or less, Amortized Costs	$ 0	$ 31,348
Due within two years, Amortized Costs	0	40,032
Total, Amortized Costs	0	71,380
Due in one year or less, Fair Value	0	31,254
Due within two years, Fair Value	0	39,763
Total, Fair Value	$ 0	$ 71,017

Investments - Average Coupon Ra

Investments - Average Coupon Rate Percentage and the Average Days to Maturity of Debt (Detail)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
US Government Agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Average Coupon Rate	0.00%	1.37%
Average Days To Maturity	0 days	370 days
Corporate Bonds and Notes [Member]
Debt Securities, Available-for-sale [Line Items]
Average Coupon Rate	0.00%	1.766%
Average Days To Maturity	0 days	392 days

Investments - Investments in Co

Investments - Investments in Continuous Unrealized Loss Position for Less Than Twelve Months (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 0	$ 49,541
Unrealized Losses	0	(299)
US Government Agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	5,472
Unrealized Losses	0	(28)
Corporate Bonds and Notes [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	44,069
Unrealized Losses	$ 0	$ (271)

Investments - Investments in _2

Investments - Investments in Continuous Unrealized Loss Position for More Than Twelve Months (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 0	$ 21,476
Unrealized Losses	0	(65)
US Government Agencies [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	1,994
Unrealized Losses	0	(6)
Corporate Bonds and Notes [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	19,482
Unrealized Losses	$ 0	$ (59)

Fair Value - Summary of Valuati

Fair Value - Summary of Valuation of Investments and Financial Instruments Pricing Levels (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	$ 27,080	$ 79,303
Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total		76,618
Money Market Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	26,308	5,601
US Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total		7,467
Corporate Bonds and Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total		63,550
Deferred Compensation Plan Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	772	2,685
(Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	27,080	8,286
(Level 1) [Member] | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total		5,601
(Level 1) [Member] | Money Market Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	26,308	5,601
(Level 1) [Member] | Deferred Compensation Plan Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	772	2,685
(Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	$ 0	71,017
(Level 2) [Member] | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total		71,017
(Level 2) [Member] | US Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total		7,467
(Level 2) [Member] | Corporate Bonds and Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total		$ 63,550

Fair Value - Additional Informa

Fair Value - Additional Information (Details) - Senior Notes [Member] - 5.25% Senior Notes due March 15, 2019 [Member] - USD ($) $ in Millions	Dec. 31, 2018	Mar. 17, 2014
Debt Instrument [Line Items]
Interest rate on Senior Notes	5.25%	5.25%
Senior notes, fair value	$ 344.2

Property and Equipment - Summar

Property and Equipment - Summary of Company's Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,380,410	$ 1,377,260
Less accumulated depreciation and amortization	(477,925)	(430,495)
Property and equipment, net	902,485	946,765
Flight Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,227,341	1,225,205
Facility & Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	67,784	64,316
Operating Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	30,832	29,913
Data Processing Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	35,889	34,747
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,798	8,202
Medical Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	8,710	8,354
Other [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 6,056	$ 6,523

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Depreciation expense related to property and equipment	$ 56.8	$ 50.6	$ 49.2

Other Assets - Schedule of Comp

Other Assets - Schedule of Company's Other Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deposits on future purchases of aircraft	$ 501	$ 501
Investment in Variable Interest Entity	519	330
Investments (Officers' Deferred Compensation Plan)	772	2,685
Deferred Cost	2,721	0
Receivables / Deposits Long Term	12,187	4,875
Other	1,678	350
Total	$ 18,378	$ 8,741

Accrued and Other Current Lia_3

Accrued and Other Current Liabilities - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Salaries & wages	$ 9,130	$ 6,240
Incentive compensation	5,226	8,991
Income taxes	895	930
Interest	7,774	8,108
Vacation payable	8,838	7,619
Group medical	1,755	1,344
Transportations tax	301	971
Operating lease	658	710
Workers compensation	846	959
Other	9,869	5,978
Total accrued liabilities	$ 45,292	$ 41,850

Debt - Components of Long-term

Debt - Components of Long-term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Principal	$ 630,000	$ 617,500
Unamortized debt issuance debt costs	1,025	1,506
5.25% Senior Notes due March 15, 2019 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Principal	500,000	500,000
Unamortized debt issuance debt costs	260	1,506
6% Related Party Term Loan [Member] | Medium-term Notes [Member]
Debt Instrument [Line Items]
Principal	130,000
Unamortized debt issuance debt costs	765
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Principal	$ 0	$ 117,500

Debt - Summary of Annual Maturi

Debt - Summary of Annual Maturities of Long-term Debt (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Debt Disclosure [Abstract]
2019	$ 500,000
2020	130,000
2021	0
2022	0
2023	0
Thereafter	0
Total	$ 630,000

Debt - Additional Information (

Debt - Additional Information (Detail)

Mar. 13, 2019USD ($)Aircraft

Sep. 28, 2018USD ($)

Mar. 13, 2023

Sep. 30, 2021

Mar. 31, 2021

Sep. 30, 2020

Sep. 30, 2021

Dec. 30, 2022

Mar. 31, 2020

Mar. 13, 2023

Sep. 30, 2020

Dec. 31, 2018USD ($)

Dec. 31, 2017USD ($)

Mar. 17, 2014USD ($)

Debt Instrument [Line Items]

Letters of credit outstanding under the facility

$ 19,800,000

$ 19,600,000

Principal

$ 630,000,000

617,500,000

5.25% Senior Notes due March 15, 2019 [Member] | Senior Notes [Member]

Debt Instrument [Line Items]

Interest rate on Senior Notes

5.25%

5.25%

Debt issued

$ 500,000,000

Principal

$ 500,000,000

500,000,000

6% Related Party Term Loan [Member] | Medium-term Notes [Member]

Debt Instrument [Line Items]

Interest rate on Senior Notes

6.00%

Debt issued

$ 130,000,000

Proceeds from Related Party Debt

130,000,000

Principal

$ 130,000,000

Letter of Credit to Secure workers Compensation Policies, Air Medical License, and a Traditional Provider Contract [Member]

Debt Instrument [Line Items]

Letters of credit outstanding under the facility

12,100,000

Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Letters of credit outstanding under the facility

7,700,000

Repayments of Lines of Credit

$ 122,700,000

Principal

$ 0

$ 117,500,000

Subsequent Event [Member] | Medium-term Notes [Member]

Debt Instrument [Line Items]

Debt issued

$ 70,000,000

Principal

$ 70,000,000

Number of aircraft securing debt agreement | Aircraft

91

Debt covenant, minimum unrestricted cash requirement at the end of each calendar month

$ 20,000,000

Debt covenant, minimum cash and cash equivalents held solly by the Company and guarantors

$ 10,000,000

Debt covenant, appraisal ratio of aircraft collateral at quarter end

4

Event of default, judgments (in excess of)

$ 2,500,000

Event of default, ERISA event liabilities (in excess of)

2,500,000

Event of default, impairments of collateral (in excess of)

$ 2,500,000

LIBOR [Member] | Subsequent Event [Member] | Medium-term Notes [Member]

Debt Instrument [Line Items]

Basis spread on variable rate (percent)

6.00%

Base Rate [Member] | Subsequent Event [Member] | Medium-term Notes [Member]

Debt Instrument [Line Items]

Basis spread on variable rate (percent)

5.00%

Scenario, Forecast [Member] | Medium-term Notes [Member]

Debt Instrument [Line Items]

Debt covenant, minimum fixed charge ratio at the end of each test period

0.9125

0.3750

0.1875

0

1.2000

Debt covenant, secured leverage ratio, at test period end

3.75

4.25

4

4.50

Income Taxes - Income before Ta

Income Taxes - Income before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
United States									$ (95,590)	$ (50,871)	$ (25,604)
Foreign									(71,870)	(570)	(1,546)
(Loss) earnings before income taxes	$ (123,148)	$ (14,062)	$ (8,777)	$ (21,473)	$ (20,319)	$ (4,899)	$ (3,150)	$ (23,073)	$ (167,460)	$ (51,441)	$ (27,149)

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
U.S. Federal:
Current	$ 0	$ 0	$ 0
Deferred	(21,061)	(57,637)	(5,488)
U. S. Federal Income Tax Expense (Benefit)	(21,061)	(57,637)	(5,488)
U.S. State:
Current	392	199	427
Deferred	(2,058)	(717)	3,218
State and Local Income Tax Expense (Benefit)	(1,666)	(518)	3,645
Foreign Income Tax Expense (Benefit), Continuing Operations [Abstract]
Foreign	2,371	108	1,374
Deferred	(5,590)	(926)	0
Foreign Income Tax Expense (Benefit)	(3,219)	(818)	1,374
Total	$ (25,946)	$ (58,973)	$ (469)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018USD ($)States	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Income Taxes Disclosure [Line Items]
Federal Statutory rate (percent)	21.00%	35.00%	35.00%
Provisional income tax benefit related to remeasurement of deferred tax balances	$ 49,200,000
Impact on state apportionment percentage changes on income tax expense (benefit)	(1,200,000)		$ (4,800,000)
Operating loss carryforwards	$ 352,400,000
Operating loss carryforwards, expiration date start	2028
Operating loss carryforwards, expiration date end	2038
Net operating loss carryforwards, majority expiration date start	2024
Net operating loss carryforwards, majority expiration date end	2038
Number of states where net operating losses will likely be forfeited | States	6
Net deferred tax liabilities	$ 54,234,000	$ 82,696,000
Foreign tax credits	18,826,000	19,453,000
Australian net operating loss carryforward	1,300,000
Valuation allowance - tax credit carryforwards	16,100,000
Valuation allowance - tax credit carryforwards recorded in 2014	200,000
Income taxes paid	2,273,000	1,231,000	2,637,000
Unrecognized tax benefits	0
Goodwill impairment	17,729,000	0	$ 0
State and Local Jurisdiction [Member]
Income Taxes Disclosure [Line Items]
Operating loss carryforwards	$ 264,600,000
Operating loss carryforwards, expiration date end	2038
Valuation allowance - state NOL carryforwards	$ 6,105,000	$ 5,998,000
State and Local Jurisdiction [Member] | SEC Schedule, 12-09, Valuation Allowance, Operating Loss Carryforward [Member]
Income Taxes Disclosure [Line Items]
Valuation allowance - state NOL carryforwards	100,000
Australian Operation [Member]
Income Taxes Disclosure [Line Items]
Net deferred tax assets	3,600,000
Deferred tax assets, net operating loss	15,200,000
New Zealand Operation [Member]
Income Taxes Disclosure [Line Items]
Net deferred tax liabilities	$ 600,000

Income Taxes - Schedule of In_2

Income Taxes - Schedule of Income Tax Expense as Percentage of Pre-Tax Earnings (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income taxes at statutory rate (percent)	21.00%	35.00%	35.00%
Valuation allowance on foreign tax credits (percent)	(0.10%)	(12.00%)	(33.00%)
Valuation allowance on state net operating loss carryforwards (percent)	(0.10%)	(2.00%)	(19.00%)
Valuation Allowance – Other (percent)	(0.10%)	(3.00%)	0.00%
Goodwill impairment (percent)	(10.60%)	0.00%	0.00%
Change in tax rate on deferred items (percent)	0.70%	0.00%	18.00%
Tax reform – Impact of change in tax rate (percent)	0.00%	96.00%	0.00%
State income taxes, net of federal benefit (percent)	1.10%	3.00%	5.00%
Foreign income tax rate differential (percent)	3.70%
Other items - net (percent)	(0.10%)	(2.00%)	(4.00%)
Total (percent)	15.50%	115.00%	2.00%
Increase (decrease) in taxes resulting from:
Income taxes at statutory rate	$ (35,167)	$ (18,004)	$ (9,502)
Valuation allowance on foreign tax credits	229	6,145	8,991
Valuation allowance on state net operating loss carryforwards	107	868	5,028
Valuation Allowance - Other	88	1,353	0
Goodwill impairment	17,729	0	0
Change in tax rate on deferred items	(1,163)	0	(4,772)
Tax reform – Impact of change in tax rate	0	(49,219)	0
State income taxes, net of federal benefit	(1,774)	(1,386)	(1,384)
Foreign income tax rate differential	(6,245)
Other items - net	250	1,270	1,170
Total	$ (25,946)	$ (58,973)	$ (469)

Income Taxes - Schedule of Tax

Income Taxes - Schedule of Tax Effects of Temporary Differences that Give Rise to Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Deferred compensation	$ 162	$ 626
Foreign tax credits	18,826	19,453
Vacation and bonus accrual	2,170	3,936
Inventory valuation	6,686	4,954
Interest disallowance	5,497	0
Rental accrual	601	747
Hurricane relief credit	1,308	1,255
Stock-based compensation	2,118	988
Other	2,653	2,235
Net operating losses	95,307	82,044
Total deferred tax assets	135,328	116,238
Valuation allowance - tax credit carryforwards	(16,127)	(16,537)
Total deferred tax assets, net	112,910	93,605
Deferred tax liabilities:
Tax depreciation in excess of book depreciation	(165,193)	(171,116)
Other	(1,951)	(5,185)
Total deferred tax liabilities	(167,144)	(176,301)
Net deferred tax liabilities	(54,234)	(82,696)
Deferred tax assets – short-term	0	0
Deferred tax assets – long-term	4,944	3,309
Deferred tax liability - long-term	(59,178)	(86,005)
Net deferred tax liabilities	(54,234)	(82,696)
State and Local Jurisdiction [Member]
Deferred tax assets:
Valuation allowance - state NOL carryforwards	(6,105)	(5,998)
Foreign Tax Authority [Member]
Deferred tax assets:
Valuation allowance - state NOL carryforwards	$ (186)	$ (98)

Earnings Per Share - Components

Earnings Per Share - Components of Basic and Diluted Earnings Per Share (Detail) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Weighted average outstanding shares of common stock, basic	15,818	15,762	15,663
Dilutive effect of unvested restricted stock units	0	0	0
Weighted average outstanding shares of common stock, diluted	15,818	15,762	15,663

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Anti-dilutive securities	0	0	24,468

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)CompensationPlan	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Defined Benefit Plan Disclosure [Line Items]
Aggregate deferred under Compensation Plan	$ 0.8	$ 2.7
Number of incentive compensation plans | CompensationPlan	1
Earnings before tax upon achieving a specified earnings threshold	3.00%
Accrued Incentive Compensation expense	$ 5.7	9	$ 1.6
Percentage of employee compensation contribution	6.00%
Percentage of vesting contribution	25.00%
Vesting period of employees	5 years
Matching contribution of employees	$ 10	9.5	10.1
Safety Incentive Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Compensation expense related to incentive plans	$ 0.7	$ 0.6	$ 0.9

Stock-based Compensation - Addi

Stock-based Compensation - Additional Information (Detail) - USD ($)	Feb. 20, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock Based Compensation [Line Items]
Compensation expense related to incentive plans		$ 6,100,000	$ 4,400,000	$ (100,000)
Non-Voting Time-Vested Restricted Stock Units [Member]
Stock Based Compensation [Line Items]
Weighted average grant date fair value (in USD per share)		$ 12.55	$ 11.42
Aggregate value of vested shares		$ 300,000	$ 1,500,000
Recognized / Unrecognized compensation cost		$ 5,900,000
Weighted average period		1 year 10 months 17 days
Aggregate value of forfeited shares			$ 400,000
Non-Voting Time-Vested Restricted Stock Units [Member] | Maximum [Member]
Stock Based Compensation [Line Items]
Aggregate value of forfeited shares		$ 77,000
Non-Voting Performance Based Restricted Stock Units [Member]
Stock Based Compensation [Line Items]
Weighted average grant date fair value (in USD per share)		$ 12.54
Aggregate value of vested shares		$ 0
Recognized / Unrecognized compensation cost		4,900,000
Aggregate value of forfeited shares		$ 2,100,000
2012 Long - Term Incentive Plan [Member] | Amended and Restated 2015 Long Term Incentive Plan [Member]
Stock Based Compensation [Line Items]
Shares available for issuance (shares)		1,149,175
Forfeiture restrictions percentage		100.00%
Vesting period of employees		3 years
2012 Long - Term Incentive Plan [Member] | Amended and Restated 2015 Long Term Incentive Plan [Member] | Non-Voting Common Stock [Member]
Stock Based Compensation [Line Items]
Common stock authorized to issue (shares)		3,500,000
Subsequent Event [Member] | Non-Voting Performance Based Restricted Stock Units [Member]
Stock Based Compensation [Line Items]
Performance period for performance RSUs	2 years
Closing market price on effective date for RSU settlement (in USD per share)	$ 2.21
Vested performance RSUs settled with cash	$ 800,000

Stock-based Compensation - Summ

Stock-based Compensation - Summary of Activity for Non-voting Time-vested Restricted Stock (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Non-Voting Time-Vested Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Share unit, Beginning Balance (shares)	534,711
Share unit, Granted (shares)	366,055
Share unit, Forfeited (shares)	(6,755)
Share unit, Vested and released to participants (shares)	(28,723)
Share unit, Ending Balance (shares)	865,288	534,711
Weighted Average Grant Fair Value, Beginning Balance (in USD per share)	$ 12.80
Weighted average grant date fair value, grants (in USD per share)	12.55	$ 11.42
Weighted Average Grants Date Fair Value, Forfeited (in USD per share)	19.86
Weighted Average Grants Date Fair Value, Vested and released to participants (in USD per share)	29.45
Weighted Average Grant Fair Value, Ending Balance (in USD per share)	$ 11.73	$ 12.80
Remaining Average Contractual Life, Ending	1 year 10 months 17 days	2 years 3 months 4 days
Aggregate Value	$ 10,146	$ 6,844
Non-Voting Performance Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Share unit, Beginning Balance (shares)	818,150
Share unit, Granted (shares)	448,012
Share unit, Forfeited (shares)	(165,397)
Share unit, Vested and released to participants (shares)	0
Share unit, Ending Balance (shares)	1,100,765	818,150
Weighted Average Grant Fair Value, Beginning Balance (in USD per share)	$ 18.60
Weighted average grant date fair value, grants (in USD per share)	12.54
Weighted Average Grants Date Fair Value, Forfeited (in USD per share)	31.33
Weighted Average Grants Date Fair Value, Vested and released to participants (in USD per share)	0
Weighted Average Grant Fair Value, Ending Balance (in USD per share)	$ 13.23	$ 18.60
Remaining Average Contractual Life, Ending	1 year 11 months 27 days	1 year 2 months 12 days
Aggregate Value	$ 14,564	$ 15,218

Stock-based Compensation - Su_2

Stock-based Compensation - Summary of Activity for Non-voting Time-vested Restricted Stock Granted to Directors (Detail) - Non-Voting Time-Vested Restricted Stock Units [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Share unit, Beginning Balance (shares)	534,711
Share unit, Granted (shares)	366,055
Share unit, Forfeited (shares)	(6,755)
Share unit, Vested and released to participants (shares)	(28,723)
Share unit, Ending Balance (shares)	865,288	534,711
Weighted Average Grant Fair Value, Beginning Balance (in USD per share)	$ 12.80
Weighted average grant date fair value, grants (in USD per share)	12.55	$ 11.42
Weighted Average Grants Date Fair Value, Forfeited (in USD per share)	19.86
Weighted Average Grants Date Fair Value, Vested and released to participants (in USD per share)	29.45
Weighted Average Grant Fair Value, Ending Balance (in USD per share)	$ 11.73	$ 12.80
Remaining Average Contractual Life, Ending	1 year 10 months 17 days	2 years 3 months 4 days
Aggregate Value	$ 10,146	$ 6,844
Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Share unit, Beginning Balance (shares)	19,680
Share unit, Granted (shares)	15,225
Share unit, Forfeited (shares)	0
Share unit, Vested and released to participants (shares)	(4,452)
Share unit, Ending Balance (shares)	30,453	19,680
Weighted Average Grant Fair Value, Beginning Balance (in USD per share)	$ 14.94
Weighted average grant date fair value, grants (in USD per share)	8.77
Weighted Average Grants Date Fair Value, Forfeited (in USD per share)	0
Weighted Average Grants Date Fair Value, Vested and released to participants (in USD per share)	21.42
Weighted Average Grant Fair Value, Ending Balance (in USD per share)	$ 10.99	$ 14.94
Remaining Average Contractual Life, Ending	2 years 2 months 9 days	2 years 8 months 16 days
Aggregate Value	$ 335	$ 292

Stock-based Compensation - Su_3

Stock-based Compensation - Summary of Activity for Non-voting Performance Units (Detail) - Non-Voting Performance Based Restricted Stock Units [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Share unit, Beginning Balance (shares)	818,150
Share unit, Granted (shares)	448,012
Share unit, Forfeited (shares)	(165,397)
Share unit, Vested and released to participants (shares)	0
Share unit, Ending Balance (shares)	1,100,765	818,150
Weighted Average Grant Fair Value, Beginning Balance (in USD per share)	$ 18.60
Weighted average grant date fair value, grants (in USD per share)	12.54
Weighted Average Grants Date Fair Value, Forfeited (in USD per share)	31.33
Weighted Average Grants Date Fair Value, Vested and released to participants (in USD per share)	0
Weighted Average Grant Fair Value, Ending Balance (in USD per share)	$ 13.23	$ 18.60
Remaining Average Contractual Life, Ending	1 year 11 months 27 days	1 year 2 months 12 days
Aggregate Value	$ 14,564	$ 15,218

Commitments and Contingencies -

Commitments and Contingencies - Summary of Rental Expense Incurred Under Leases (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Aircraft	$ 35,740	$ 39,815	$ 44,130
Other	11,718	9,504	9,451
Total	$ 47,458	$ 49,319	$ 53,581

Commitments and Contingencies_2

Commitments and Contingencies - Summary of Remaining Aggregate Lease Commitments Under Operating Leases Having Initial Non-Cancelable Terms in Excess of One Year (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Operating Leased Assets [Line Items]
2019	$ 36,470
2020	32,809
2021	31,127
2022	28,776
2023	19,686
Thereafter	10,668
Total	159,536
Other [Member]
Operating Leased Assets [Line Items]
2019	6,765
2020	5,403
2021	3,855
2022	2,018
2023	516
Thereafter	761
Total	19,318
Aircraft [Member]
Operating Leased Assets [Line Items]
2019	29,705
2020	27,406
2021	27,272
2022	26,758
2023	19,170
Thereafter	9,907
Total	$ 140,218

Commitments and Contingencies_3

Commitments and Contingencies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)Land_Parcel
Long-term Purchase Commitment [Line Items]
Aggregate amount of guarantees and bonds	$ 1,000
Aggregate estimated probable liability environmental matters	$ 150
Number of parcels of land exists | Land_Parcel	2
2019 [Member]
Long-term Purchase Commitment [Line Items]
Aggregate purchase price for aircraft	$ 129,000
2020 [Member]
Long-term Purchase Commitment [Line Items]
Aggregate purchase price for aircraft	$ 22,700

Business Segments and Geograp_3

Business Segments and Geographic Areas - Schedule of Accounts Receivable and Revenue by Major Customers by Reporting Segments (Detail) - Segment	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue, Major Customer [Line Items]
Number of reportable segments	3
Customer Concentration Risk [Member] | Accounts Receivable [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	10.70%
Customer Concentration Risk [Member] | Oil and Gas [Member] | Operating Revenues [Member] | Customer A [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	17.00%	14.00%	14.00%
Customer Concentration Risk [Member] | Oil and Gas [Member] | Operating Revenues [Member] | Customer B [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	7.00%	9.00%	10.00%
Customer Concentration Risk [Member] | Air Medical and Technical Services [Member] | Operating Revenues [Member] | Customer C [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	0.00%	0.00%	5.00%
Concentration of Credit Risk [Member] | Oil and Gas [Member] | Accounts Receivable [Member] | Customer A [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	15.00%	11.00%
Concentration of Credit Risk [Member] | Oil and Gas [Member] | Accounts Receivable [Member] | Customer B [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	5.00%	5.00%
Concentration of Credit Risk [Member] | Air Medical and Technical Services [Member] | Accounts Receivable [Member] | Customer C [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	0.00%	10.00%

Business Segments and Geograp_4

Business Segments and Geographic Areas - Schedule of Financial Information Concerning Reportable Operating Segments (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Total operating revenues	$ 176,023	$ 168,787	$ 169,243	$ 160,370	$ 148,336	$ 150,167	$ 146,424	$ 134,618	$ 674,423	$ 579,545	$ 634,098
Total segment direct expenses									631,807	546,699	592,550
Total segment selling, general and administrative expenses									66,685	53,817	44,418
Total net segment profit									(133,658)	(22,022)	224
Impairment of assets									(109,024)	(368)	(407)
Interest expense									(33,981)	(32,183)	(30,644)
(Loss) earnings before income taxes	$ (123,148)	$ (14,062)	$ (8,777)	$ (21,473)	$ (20,319)	$ (4,899)	$ (3,150)	$ (23,073)	(167,460)	(51,441)	(27,149)
Reportable Operating Segments [Member]
Segment Reporting Information [Line Items]
Total operating revenues									674,423	579,545	634,098
Total segment direct expenses									631,619	547,084	592,399
Total segment selling, general and administrative expenses									33,736	19,746	18,808
Total segment expenses									665,355	566,830	611,207
Total net segment profit									9,068	12,715	22,891
Reportable Operating Segments [Member] | Oil and Gas [Member]
Segment Reporting Information [Line Items]
Total operating revenues									380,238	298,398	324,129
Total segment direct expenses									371,930	321,272	344,640
Total segment selling, general and administrative expenses									18,485	5,899	6,739
Total net segment profit									(10,177)	(28,773)	(27,250)
Reportable Operating Segments [Member] | Air Medical [Member]
Segment Reporting Information [Line Items]
Total operating revenues									257,132	257,273	281,868
Total segment direct expenses									230,840	208,987	227,877
Total segment selling, general and administrative expenses									13,833	12,442	10,968
Total net segment profit									12,459	35,844	43,023
Reportable Operating Segments [Member] | Technical Services [Member]
Segment Reporting Information [Line Items]
Total operating revenues									37,053	23,874	28,101
Total segment direct expenses									28,849	16,825	19,882
Total segment selling, general and administrative expenses									1,418	1,405	1,101
Total net segment profit									6,786	5,644	7,118
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Impairment of assets									(109,024)	(368)	(407)
Other, net									(574)	2,466	6,621
Interest expense									(33,981)	(32,183)	(30,644)
Corporate [Member]
Segment Reporting Information [Line Items]
Unallocated selling, general and administrative costs									$ (32,949)	$ (34,071)	$ (25,610)

Business Segments and Geograp_5

Business Segments and Geographic Areas - Summary of Gains on Disposition of Property and Equipment and Other Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting, Asset Reconciling Item [Line Items]
Expenditures for long-lived assets	$ 42,908	$ 58,478	$ 82,871
Depreciation and amortization	79,254	68,027	65,743
Total assets	1,262,226	1,401,846
Reportable Operating Segments [Member] | Oil and Gas [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Expenditures for long-lived assets	34,171	52,525	59,278
Depreciation and amortization	47,723	39,655	40,170
Total assets	594,331	722,734
Reportable Operating Segments [Member] | Air Medical [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Expenditures for long-lived assets	7,268	5,696	22,429
Depreciation and amortization	22,606	20,413	19,716
Total assets	387,701	372,646
Reportable Operating Segments [Member] | Technical Services [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Depreciation and amortization	499	581	564
Total assets	5,515	5,979
Corporate [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Expenditures for long-lived assets	1,469	257	1,164
Depreciation and amortization	8,426	7,378	$ 5,293
Total assets	$ 274,679	$ 300,487

Business Segments and Geograp_6

Business Segments and Geographic Areas - Summary of Company's Revenues from External Customers and Long-Lived Assets, by Geographical Areas (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Total operating revenues	$ 176,023	$ 168,787	$ 169,243	$ 160,370	$ 148,336	$ 150,167	$ 146,424	$ 134,618	$ 674,423	$ 579,545	$ 634,098
Total Long-Lived Assets	902,485				946,765				902,485	946,765
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total operating revenues									516,717	530,115	579,300
Total Long-Lived Assets	552,350				601,530				552,350	601,530
International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total operating revenues									157,706	49,430	$ 54,798
Total Long-Lived Assets	$ 350,135				$ 345,235				$ 350,135	$ 345,235

Quarterly Financial Data - Summ

Quarterly Financial Data - Summary of Condensed Quarterly Results of Operations (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Operating revenues, net	$ 176,023	$ 168,787	$ 169,243	$ 160,370	$ 148,336	$ 150,167	$ 146,424	$ 134,618	$ 674,423	$ 579,545	$ 634,098
(Loss) gain on disposition of assets, net	45	0	(171)	879	287	4	7	0	(753)	(298)	3,350
(Loss) earnings before income taxes	(123,148)	(14,062)	(8,777)	(21,473)	(20,319)	(4,899)	(3,150)	(23,073)	(167,460)	(51,441)	(27,149)
Net earnings (loss)	$ (105,907)	$ (11,531)	$ (7,093)	$ (16,983)	$ 29,330	$ (3,277)	$ (3,273)	$ (15,248)	$ (141,514)	$ 7,532	$ (26,680)
Net (loss) earnings per share
Basic (USD per share)	$ (6.70)	$ (0.73)	$ (0.45)	$ (1.07)	$ 1.87	$ (0.21)	$ (0.21)	$ (0.97)	$ (8.95)	$ 0.48	$ (1.70)
Diluted (USD per share)	$ (6.70)	$ (0.73)	$ (0.45)	$ (1.07)	$ 1.87	$ (0.21)	$ (0.21)	$ (0.97)	$ (8.95)	$ 0.48	$ (1.70)

Variable Interest Entity - Addi

Variable Interest Entity - Additional Information (Detail) - PHI Century Limited [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Variable Interest Entity [Line Items]
Investment in the common stock	49.00%
PHIC's date of incorporation	May 26, 2011
Earnings (loss) in equity of unconsolidated affiliate	$ 0.2	$ (1)
Trade receivables	4.8	4
Other assets	0.5	$ 0.5
Accounts Receivable - Other [Member]
Variable Interest Entity [Line Items]
Loan to affiliate	$ 0.4

Condensed Consolidating Finan_3

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Mar. 17, 2014
Supplemental Guarantor Financial Information [Line Items]
Ownership of subsidiaries (percent)		100.00%
Impact of misclassifications	$ 0
5.25% Senior Notes due March 15, 2019 [Member] | Senior Notes [Member]
Supplemental Guarantor Financial Information [Line Items]
Debt issued			$ 500,000,000
Interest rate on Senior Notes		5.25%	5.25%
Parent Company Only (issuer) [Member] | Other Assets [Member]
Supplemental Guarantor Financial Information [Line Items]
Impact of misclassifications	(131,900,000)
Parent Company Only (issuer) [Member] | Investment in Subsidiaries and Others [Member]
Supplemental Guarantor Financial Information [Line Items]
Impact of misclassifications	$ 131,900,000

Condensed Consolidating Finan_4

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidating Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 29, 2017	Dec. 31, 2016	Dec. 31, 2015
Current Assets:
Cash and cash equivalents	$ 50,874	$ 8,770		$ 2,596	$ 2,407
Short-term investments	14,232	64,237
Accounts receivable - net	182,465	185,979
Inventories of spare parts – net	56,698	80,881
Prepaid expenses	11,419	11,475
Income taxes receivable	950	1,271
Total current assets	316,638	352,613
Property and equipment – net	902,485	946,765
Restricted cash and investments	19,781	12,396
Other assets	18,378	8,741
Deferred income taxes	4,944	3,309
Goodwill	0	61,299	$ 61,299
Intangibles	0	16,723
Total assets	1,262,226	1,401,846
Current Liabilities:
Senior Notes issued March 17, 2014	499,740	0
Accounts payable	50,289	37,186
Accrued and other current liabilities	45,292	41,850
Total current liabilities	595,321	79,036
Long-term debt	129,235	615,994
Deferred income taxes and other long-term liabilities	64,237	94,162
Shareholders’ Equity:
Common stock and paid-in capital	315,898	309,933
Accumulated other comprehensive loss	(3,952)	(280)
Retained earnings	161,487	303,001
Total shareholders’ equity	473,433	612,654		599,778	626,998
Total liabilities and shareholders’ equity	1,262,226	1,401,846
Parent Company Only (issuer) [Member]
Current Assets:
Cash and cash equivalents				36	46
Guarantor Subsidiaries [Member]
Current Assets:
Cash and cash equivalents				2,100	1,672
Non-Guarantor Subsidiaries [Member]
Current Assets:
Cash and cash equivalents				460	689
Reportable Legal Entities [Member] | Parent Company Only (issuer) [Member]
Current Assets:
Cash and cash equivalents	39,091	47
Short-term investments	14,232	64,237
Accounts receivable - net	64,416	90,077
Inventories of spare parts – net	43,933	68,737
Prepaid expenses	7,295	8,348
Income taxes receivable	394	345
Total current assets	169,361	231,791
Investment in subsidiaries and others	471,790	529,222
Property and equipment – net	576,763	617,488
Restricted cash and investments	19,781	12,382
Other assets	17,179	7,833
Total assets	1,254,874	1,398,716
Current Liabilities:
Senior Notes issued March 17, 2014	499,740
Accounts payable	44,089	28,130
Accrued and other current liabilities	25,158	23,147
Intercompany payable	74,336	113,387
Total current liabilities	643,323	164,664
Long-term debt	129,235	615,994
Deferred income taxes and other long-term liabilities	4,934	5,404
Shareholders’ Equity:
Common stock and paid-in capital	315,898	309,933
Accumulated other comprehensive loss	(3)	(280)
Retained earnings	161,487	303,001
Total shareholders’ equity	477,382	612,654
Total liabilities and shareholders’ equity	1,254,874	1,398,716
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Current Assets:
Cash and cash equivalents	1,259	1,072
Accounts receivable - net	93,060	74,886
Intercompany receivable	91,468	126,366
Inventories of spare parts – net	9,577	9,049
Prepaid expenses	2,520	1,898
Income taxes receivable	556	9
Total current assets	198,440	213,280
Property and equipment – net	287,375	284,984
Other assets	1,199	908
Total assets	487,014	499,172
Current Liabilities:
Accounts payable	4,587	4,636
Accrued and other current liabilities	12,335	10,577
Total current liabilities	16,922	15,213
Deferred income taxes and other long-term liabilities	58,752	84,300
Shareholders’ Equity:
Common stock and paid-in capital	77,951	77,951
Retained earnings	333,389	321,708
Total shareholders’ equity	411,340	399,659
Total liabilities and shareholders’ equity	487,014	499,172
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Current Assets:
Cash and cash equivalents	10,524	7,651
Accounts receivable - net	28,812	38,020
Inventories of spare parts – net	3,188	3,095
Prepaid expenses	1,604	1,229
Income taxes receivable		917
Total current assets	44,128	50,912
Property and equipment – net	38,347	44,293
Restricted cash and investments		14
Other assets	0	0
Deferred income taxes	4,944	3,309
Goodwill		61,299
Intangibles		16,723
Total assets	87,419	176,550
Current Liabilities:
Accounts payable	5,452	21,425
Accrued and other current liabilities	7,799	8,126
Intercompany payable	17,116	12,978
Total current liabilities	30,367	42,529
Deferred income taxes and other long-term liabilities	551	4,458
Shareholders’ Equity:
Common stock and paid-in capital	132,650	133,296
Accumulated other comprehensive loss	(3,949)
Retained earnings	(72,200)	(3,733)
Total shareholders’ equity	56,501	129,563
Total liabilities and shareholders’ equity	87,419	176,550
Eliminations [Member]
Current Assets:
Cash and cash equivalents				$ 0	$ 0
Accounts receivable - net	(3,823)	(17,004)
Intercompany receivable	(91,468)	(126,366)
Total current assets	(95,291)	(143,370)
Investment in subsidiaries and others	(471,790)	(529,222)
Total assets	(567,081)	(672,592)
Current Liabilities:
Accounts payable	(3,839)	(17,005)
Intercompany payable	(91,452)	(126,365)
Total current liabilities	(95,291)	(143,370)
Shareholders’ Equity:
Common stock and paid-in capital	(210,601)	(211,247)
Retained earnings	(261,189)	(317,975)
Total shareholders’ equity	(471,790)	(529,222)
Total liabilities and shareholders’ equity	$ (567,081)	$ (672,592)

Condensed Consolidating Finan_5

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidating Statements of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Income Statements, Captions [Line Items]
Operating revenues, net	$ 176,023	$ 168,787	$ 169,243	$ 160,370	$ 148,336	$ 150,167	$ 146,424	$ 134,618	$ 674,423	$ 579,545	$ 634,098
Expenses:
Direct expenses									631,807	546,699	592,550
Selling, general, and administrative expenses									66,685	53,817	44,418
Total operating expenses									698,492	600,516	636,968
Loss (gain) on disposition of assets, net	(45)	0	171	(879)	(287)	(4)	(7)	0	753	298	(3,350)
Impairment of assets									109,024	368	407
Equity in profit (loss) of unconsolidated affiliate									(188)	385	(151)
Operating (loss) income									(133,658)	(22,022)	224
Interest expense									33,981	32,183	30,644
Other income, net									(179)	(2,764)	(3,271)
Total expenses									33,802	29,419	27,373
(Loss) earnings before income taxes	(123,148)	(14,062)	(8,777)	(21,473)	(20,319)	(4,899)	(3,150)	(23,073)	(167,460)	(51,441)	(27,149)
Income tax (benefit) expense									(25,946)	(58,973)	(469)
Net earnings (loss)	$ (105,907)	$ (11,531)	$ (7,093)	$ (16,983)	$ 29,330	$ (3,277)	$ (3,273)	$ (15,248)	(141,514)	7,532	(26,680)
Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues, net									(28,406)	(17,004)
Expenses:
Direct expenses									(28,406)	(17,004)
Selling, general, and administrative expenses									(18)		(18)
Total operating expenses									(28,424)	(17,004)	(18)
Operating (loss) income									18	0	18
Equity in net earnings of consolidated subsidiaries									(56,786)	38,553	22,182
Other income, net									18		18
Total expenses									(56,768)	38,553	22,200
(Loss) earnings before income taxes									56,786	(38,553)	(22,182)
Net earnings (loss)									56,786	(38,553)	(22,182)
Reportable Legal Entities [Member] | Parent Company Only (issuer) [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues, net									329,268	310,449	339,829
Expenses:
Direct expenses									331,785	326,152	347,532
Selling, general, and administrative expenses									40,715	41,134	32,911
Total operating expenses									372,500	367,286	380,443
Loss (gain) on disposition of assets, net									774	300	(3,350)
Impairment of assets									31,824	368
Equity in profit (loss) of unconsolidated affiliate									(188)	1,021	(151)
Operating (loss) income									(75,642)	(58,526)	(37,520)
Equity in net earnings of consolidated subsidiaries									56,786	(38,553)	(22,182)
Interest expense									33,964	32,161	30,585
Other income, net									(547)	(2,757)	(3,284)
Total expenses									90,203	(9,149)	5,119
(Loss) earnings before income taxes									(165,845)	(49,377)	(42,639)
Income tax (benefit) expense									(24,331)	(56,909)	(15,959)
Net earnings (loss)									(141,514)	7,532	(26,680)
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues, net									263,679	262,229	293,329
Expenses:
Direct expenses									236,366	212,691	237,635
Selling, general, and administrative expenses									13,834	12,462	10,984
Total operating expenses									250,200	225,153	248,619
Loss (gain) on disposition of assets, net										(2)
Operating (loss) income									13,479	37,078	44,710
Interest expense									13	22	46
Other income, net										(2)	(5)
Total expenses									13	20	41
(Loss) earnings before income taxes									13,466	37,058	44,669
Income tax (benefit) expense									1,785	(1,138)	15,490
Net earnings (loss)									11,681	38,196	29,179
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues, net									109,882	23,871	940
Expenses:
Direct expenses									92,062	24,860	7,383
Selling, general, and administrative expenses									12,154	221	541
Total operating expenses									104,216	25,081	7,924
Loss (gain) on disposition of assets, net									(21)
Impairment of assets									77,200
Equity in profit (loss) of unconsolidated affiliate										(636)
Operating (loss) income									(71,513)	(574)	(6,984)
Interest expense									4		13
Other income, net									350	(5)
Total expenses									354	(5)	13
(Loss) earnings before income taxes									(71,867)	(569)	(6,997)
Income tax (benefit) expense									(3,400)	(926)
Net earnings (loss)									$ (68,467)	$ 357	$ (6,997)

Condensed Consolidating Finan_6

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidated Statements of Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Financial Statements, Captions [Line Items]
Net earnings (loss)	$ (105,907)	$ (11,531)	$ (7,093)	$ (16,983)	$ 29,330	$ (3,277)	$ (3,273)	$ (15,248)	$ (141,514)	$ 7,532	$ (26,680)
Unrealized gain (loss) on short-term investments									364	310	241
Changes in pension plan assets and benefit obligations									(1)	(3)	(39)
Tax effect									(85)	(109)	(113)
Other unrealized gain											0
Currency translation adjustment									(3,950)	0	0
Total comprehensive income (loss)									(145,186)	7,730	(26,591)
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net earnings (loss)									56,786	(38,553)	(22,182)
Total comprehensive income (loss)									56,786	(38,553)	(22,182)
Reportable Legal Entities [Member] | Parent Company Only (issuer) [Member]
Condensed Financial Statements, Captions [Line Items]
Net earnings (loss)									(141,514)	7,532	(26,680)
Unrealized gain (loss) on short-term investments									364	310	241
Changes in pension plan assets and benefit obligations									(1)	(3)	(39)
Tax effect									(85)	(109)	(113)
Other unrealized gain											0
Currency translation adjustment									0
Total comprehensive income (loss)									(141,236)	7,730	(26,591)
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net earnings (loss)									11,681	38,196	29,179
Total comprehensive income (loss)									11,681	38,196	29,179
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net earnings (loss)									(68,467)	357	(6,997)
Currency translation adjustment									(3,950)
Total comprehensive income (loss)									$ (72,417)	$ 357	$ (6,997)

Condensed Consolidating Finan_7

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidating Statements of Cash Flows (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities	[1]	$ 17,648	$ (19,103)	$ (564)
Investing activities:
Purchase of property and equipment		(43,176)	(56,757)	(81,842)
Proceeds from asset dispositions		14,245	1,296	14,983
Purchase of short-term investments		(284,481)	(637,980)	(321,453)
Proceeds from sale of short-term investments		334,488	862,942	316,543
Payments of deposits on aircraft		0	0	(2,249)
Loan to third party		0	(824)	0
Business acquisitions net of cash acquired		0	(126,644)	0
Loan to unconsolidated affiliate		(274)	0	(1,200)
Net cash provided by (used in) investing activities		20,802	42,033	(75,218)
Financing activities:
Debt issuance costs		(874)	0	0
Repurchase of common stock		(106)	(256)	(529)
Proceeds from line of credit		34,295	152,150	264,700
Payments on line of credit		(151,795)	(168,650)	(188,200)
Proceeds from related party term loan		130,000	0	0
Due to/from affiliate, net		0	0	0
Net cash provided by (used in) financing activities		11,520	(16,756)	75,971
Effect of exchange rate changes on cash and cash equivalents		(176)	0	0
Increase (decrease) in cash, cash equivalents and restricted cash		49,794	6,174	189
Cash, cash equivalents and restricted cash at beginning of period		8,770	2,596	2,407
Cash, cash equivalents and restricted cash at end of period		58,564	8,770	2,596
Parent Company Only (issuer) [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities				(46,738)
Investing activities:
Purchase of property and equipment				(81,484)
Proceeds from asset dispositions				14,983
Purchase of short-term investments				(321,453)
Proceeds from sale of short-term investments				316,543
Payments of deposits on aircraft				(2,249)
Loan to unconsolidated affiliate				(1,200)
Net cash provided by (used in) investing activities				(74,860)
Financing activities:
Repurchase of common stock				(529)
Proceeds from line of credit				264,700
Payments on line of credit				(188,200)
Due to/from affiliate, net				45,617
Net cash provided by (used in) financing activities				121,588
Increase (decrease) in cash, cash equivalents and restricted cash				(10)
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities				52,873
Investing activities:
Net cash provided by (used in) investing activities				0
Financing activities:
Due to/from affiliate, net				(52,445)
Net cash provided by (used in) financing activities				(52,445)
Increase (decrease) in cash, cash equivalents and restricted cash				428
Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities				(6,699)
Investing activities:
Purchase of property and equipment				(358)
Net cash provided by (used in) investing activities				(358)
Financing activities:
Due to/from affiliate, net				6,828
Net cash provided by (used in) financing activities				6,828
Increase (decrease) in cash, cash equivalents and restricted cash				(229)
Eliminations [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities		0	0	0
Investing activities:
Net cash provided by (used in) investing activities		0	0	0
Financing activities:
Net cash provided by (used in) financing activities		0	0	0
Increase (decrease) in cash, cash equivalents and restricted cash		0	0	0
Cash, cash equivalents and restricted cash at beginning of period		0	0
Cash, cash equivalents and restricted cash at end of period		0	0	0
Reportable Legal Entities [Member] | Parent Company Only (issuer) [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities		24,123	(62,581)
Investing activities:
Purchase of property and equipment		(40,865)	(56,757)
Proceeds from asset dispositions		14,245	1,296
Purchase of short-term investments		(284,481)	(637,980)
Proceeds from sale of short-term investments		334,488	862,942
Payments of deposits on aircraft			0
Loan to third party			(824)
Business acquisitions net of cash acquired			(130,788)
Loan to unconsolidated affiliate		(274)
Net cash provided by (used in) investing activities		23,113	37,889
Financing activities:
Debt issuance costs		(874)
Repurchase of common stock		(106)	(256)
Proceeds from line of credit		34,295	152,150
Payments on line of credit		(151,795)	(168,650)
Proceeds from related party term loan		130,000
Due to/from affiliate, net		(12,022)	41,459
Net cash provided by (used in) financing activities		(502)	24,703
Increase (decrease) in cash, cash equivalents and restricted cash		46,734	11
Cash, cash equivalents and restricted cash at beginning of period		47	36
Cash, cash equivalents and restricted cash at end of period		46,781	47	36
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities		(16,952)	40,628
Investing activities:
Net cash provided by (used in) investing activities		0	0
Financing activities:
Due to/from affiliate, net		17,139	(41,656)
Net cash provided by (used in) financing activities		17,139	(41,656)
Increase (decrease) in cash, cash equivalents and restricted cash		187	(1,028)
Cash, cash equivalents and restricted cash at beginning of period		1,072	2,100
Cash, cash equivalents and restricted cash at end of period		1,259	1,072	2,100
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash (used in) provided by operating activities		10,477	2,850
Investing activities:
Purchase of property and equipment		(2,311)
Business acquisitions net of cash acquired			4,144
Net cash provided by (used in) investing activities		(2,311)	4,144
Financing activities:
Due to/from affiliate, net		(5,117)	197
Net cash provided by (used in) financing activities		(5,117)	197
Effect of exchange rate changes on cash and cash equivalents		(176)
Increase (decrease) in cash, cash equivalents and restricted cash		2,873	7,191
Cash, cash equivalents and restricted cash at beginning of period		7,651	460
Cash, cash equivalents and restricted cash at end of period		$ 10,524	$ 7,651	$ 460
[1]	Net of the effect of business acquisitions.

Asset Impairment (Details)

Asset Impairment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 61,600	$ 61,643	$ 0	$ 0
Intangible assets	15,500	15,557	0	0
Aircraft and related inventory	$ 23,200	31,824	368	407
Total		$ 109,024	$ 368	$ 407

Asset Impairment - Additional I

Asset Impairment - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Impaired Long-Lived Assets Held and Used [Line Items]
Goodwill	$ 61,600	$ 61,643	$ 0	$ 0
Impairment of assets		109,024	368	407
Intangible assets	15,500	15,557	0	0
Aircraft	23,200	$ 31,824	$ 368	$ 407
Direct Expenses [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Inventory Write-down	$ 8,600

Schedule II - Valuation and Q_2

Schedule II - Valuation and Qualifying Consolidated Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 7,239	$ 6,021	$ 5,151
Additions Charged to Costs and Expenses	0	1,218	870
Deductions	1,135	0	0
Balance at End of Year	6,104	7,239	6,021
SEC Schedule, 12-09, Reserve, Inventory [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	20,875	17,305	15,385
Additions Charged to Costs and Expenses	0	3,570	1,920
Deductions	2,940	0	0
Balance at End of Year	17,935	20,875	17,305
Allowance for Contractual Discounts [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	117,782	111,856	103,601
Additions Charged to Costs and Expenses	541,709	480,645	483,449
Deductions	535,700	474,719	475,194
Balance at End of Year	123,791	117,782	111,856
Allowance for Uncompensated Care [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	52,515	46,310	41,924
Additions Charged to Costs and Expenses	78,298	78,883	88,787
Deductions	78,873	72,678	84,401
Balance at End of Year	$ 51,940	$ 52,515	$ 46,310