PHI (PHIG) 10-K 29 Feb 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2015	Feb. 22, 2016	Jun. 30, 2015
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Trading Symbol	PHII
Entity Registrant Name	PHI INC
Entity Central Index Key	350,403
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Public Float			$ 265,080,759
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		12,677,707

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current Assets:
Cash	$ 2,407	$ 6,270
Short-term investments	284,523	185,244
Accounts receivable - net
Trade	138,309	178,833
Other	6,469	1,928
Inventories of spare parts - net	69,491	73,793
Prepaid expenses	8,951	9,314
Deferred income taxes	10,379	9,915
Income taxes receivable	761	1,227
Total current assets	521,290	466,524
Property and equipment - net	883,529	877,818
Restricted investments	15,336	15,485
Other	10,177	16,253
Total assets	1,430,332	1,376,080
Current Liabilities:
Accounts payable	31,373	27,700
Accrued and other current liabilities	44,759	52,812
Total current liabilities	76,132	80,512
Long-term debt	557,500	543,000
Deferred income taxes	153,645	140,532
Other long-term liabilities	$ 16,057	$ 14,968
Commitments and contingencies (Note 12)
Shareholders' Equity:
Additional paid-in capital	$ 304,884	$ 301,533
Accumulated other comprehensive loss	(567)	(211)
Retained earnings	321,121	294,197
Total shareholders' equity	626,998	597,068
Total liabilities and shareholders' equity	1,430,332	1,376,080
Voting Common Stock [Member]
Shareholders' Equity:
Common stock	291	291
Non-Voting Common Stock [Member]
Shareholders' Equity:
Common stock	1,269	1,258
Total shareholders' equity	$ 1,269	$ 1,258

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
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	25,000,000	25,000,000
Common stock, shares issued	12,576,916	12,458,992
Common stock, shares outstanding	12,576,916	12,458,992

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Operating revenues, net	$ 804,228	$ 836,270	$ 856,500
Expenses:
Direct expenses	687,050	670,007	713,090
Selling, general and administrative expenses	46,422	43,171	38,820
Total operating expenses	733,472	713,178	751,910
Loss (gain) on disposition of assets, net	339	848	(16,604)
Impairments of assets		10,508	1,648
Equity in loss of unconsolidated affiliate	306	96	262
Operating income	70,111	111,640	119,284
Interest expense	29,066	29,510	29,756
Loss on debt extinguishment		29,833
Other income, net	(2,211)	(818)	(613)
Total expenses	26,855	58,525	29,143
Earnings before income taxes	43,256	53,115	90,141
Income tax expense	16,332	20,427	31,185
Net earnings	$ 26,924	$ 32,688	$ 58,956
Earnings per share:
Basic	$ 1.73	$ 2.11	$ 3.81
Diluted	$ 1.72	$ 2.08	$ 3.77
Weighted average shares outstanding:
Basic	15,566	15,483	15,474
Diluted	15,642	15,685	15,639

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net earnings	$ 2,438	$ 7,669	$ 6,454	$ 10,363	$ 7,392	$ 17,249	$ 13,368	$ (5,321)	$ 26,924	$ 32,688	$ 58,956
Net unrealized (loss) gain on short-term investments									(641)	(285)	44
Other unrealized gain (loss)									24	(24)
Changes in pension plan assets and benefit obligations									7	17	(2)
Tax impact of the above-listed adjustments									254	105	(15)
Total comprehensive income									$ 26,568	$ 32,501	$ 58,983

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Non-Voting Common Stock [Member]	Voting Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]
Balance at Dec. 31, 2012	$ 499,615	$ 1,246	$ 285	$ 295,582	$ (51)	$ 202,553
Balance, Shares at Dec. 31, 2012		12,565	2,853
Net earnings	58,956					58,956
Unrealized gain (loss) on short-term investments	28				28
Changes in pension plan assets and benefit obligations	(1)				(1)
Amortization of unearned stock-based compensation	2,403			2,403
Issuance of non-voting common stock (upon vesting of restricted stock units)	17	$ 17
Issuance of non-voting common stock (upon vesting of restricted stock units), shares		4
Cancellation of restricted non-voting stock units for tax withholdings on vested shares	(65)	$ (6)		(59)
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, shares		(1)
Issuance of voting common stock (upon vesting of restricted stock units)	9		$ 9
Issuance of voting common stock (upon vesting of restricted stock units), shares			84
Cancellation of restricted voting stock units for tax withholdings on vested shares	(997)		$ (3)	(994)
Cancellation of restricted voting stock units for tax withholdings on vested shares, shares			(31)
Balance at Dec. 31, 2013	559,965	$ 1,257	$ 291	296,932	(24)	261,509
Balance, Shares at Dec. 31, 2013		12,568	2,906
Net earnings	32,688					32,688
Unrealized gain (loss) on short-term investments	(173)				(173)
Changes in pension plan assets and benefit obligations	10				10
Amortization of unearned stock-based compensation	4,753			4,753
Issuance of non-voting common stock (upon vesting of restricted stock units)	1	$ 1
Issuance of non-voting common stock (upon vesting of restricted stock units), shares		12
Cancellation of restricted non-voting stock units for tax withholdings on vested shares	(178)			(178)
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, shares		(4)
Other	2			26	(24)
Balance at Dec. 31, 2014	597,068	$ 1,258	$ 291	301,533	(211)	294,197
Balance, Shares at Dec. 31, 2014		12,576	2,906
Net earnings	26,924					26,924
Unrealized gain (loss) on short-term investments	(384)				(384)
Changes in pension plan assets and benefit obligations	4				4
Amortization of unearned stock-based compensation	5,799			5,799
Issuance of non-voting common stock (upon vesting of restricted stock units)	18	$ 18
Issuance of non-voting common stock (upon vesting of restricted stock units), shares		179
Cancellation of restricted non-voting stock units for tax withholdings on vested shares	(2,203)	$ (7)		(2,196)
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, shares		(70)
Purchase and retirement of treasury stock	(252)			(252)
Other	24				24
Balance at Dec. 31, 2015	$ 626,998	$ 1,269	$ 291	$ 304,884	$ (567)	$ 321,121
Balance, Shares at Dec. 31, 2015		12,685	2,906

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating activities:
Net earnings	$ 26,924	$ 32,688	$ 58,956
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	71,618	50,848	42,848
Deferred income taxes	12,894	16,071	21,921
Loss (gain) on asset dispositions	339	848	(16,604)
Equity in loss of unconsolidated affiliate	306	96	262
Loss on debt extinguishment		29,833
Impairment of assets		10,507	1,648
Inventory valuation reserves	3,231
Other	(1,277)	(96)	427
Changes in operating assets and liabilities:
Accounts receivable	36,579	(6,758)	(32,123)
Inventories of spare parts	1,441	(2,656)	(5,062)
Income taxes receivable	466	644	(1,015)
Other assets	(14,998)	(1,212)	3,104
Accounts payable and accrued liabilities	(3,859)	(10,946)	27,191
Other long-term liabilities	254	(348)	3,543
Net cash provided by operating activities	133,918	119,519	105,096
Investing activities:
Purchase of property and equipment	(57,123)	(157,690)	(102,726)
Proceeds from asset dispositions	5,236	10,266	42,197
Purchase of short-term investments	(608,649)	(465,094)	(375,503)
Proceeds from sale of short-term investments	505,966	363,110	338,970
Payments of deposits on aircraft	(1,273)	(6,948)	(9,318)
Refunds of deposits on aircraft	6,010	11,506	8,161
Loan to unconsolidated affiliate		(200)
Net cash used in investing activities	(149,833)	(245,050)	(98,219)
Financing activities:
Proceeds from issuance of Senior Notes due 2019		500,000
Repayment of Senior Notes due 2018		(300,000)
Premium and costs to retire debt early		(26,749)
Debt issuance costs		(6,232)
Repurchase of common stock	(2,448)	(152)	(1,037)
Proceeds from line of credit	232,660	264,253	164,771
Payments on line of credit	(218,160)	(300,253)	(172,526)
Net cash provided by (used in) financing activities	12,052	130,867	(8,792)
(Decrease) increase in cash	(3,863)	5,336	(1,915)
Cash, beginning of year	6,270	934	2,849
Cash, end of year	2,407	6,270	934
Cash paid during the period for:
Interest	27,657	25,415	28,675
Income Taxes	5,521	9,590	1,161
Accrued payables related to purchases of property and equipment	$ 1,339	$ 192	$ 176

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	(1) 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 North America and to a lesser extent in 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 and the Middle East. 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 earnings (loss) of unconsolidated affiliates. At December 31, 2015, Al A. Gonsoulin, Chairman of the Board and Chief Executive Officer, beneficially owned stock representing approximately 70.2% 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. 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, Inventories of spare parts, 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, Income taxes, Healthcare insurance claims and workers’ compensation liability, and Impairment of long-lived 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. Provisions for contractual discounts and uncompensated care that we applied to our Air Medical trade receivables (expressed as a percentage of total segment billings) at December 31 were as follows: 2015 2014 Allowance for contractual discounts 56 % 53 % Allowance for uncompensated care 23 % 23 % Short-term Investments Short-term investments consist of money market funds, 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. The Company recorded less than $0.9 million in net unrealized losses in 2015. These losses are reflected as a separate component of stockholders’ equity. 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 $15.4 million and $13.5 million at December 31, 2015 and 2014, 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 five to fifteen years for flight equipment and three to ten 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 six to ten 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 (historical as of 2007). 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 asset. 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 assets for impairment annually, or more frequently if events or a change of circumstances indicate that an impairment may have occurred. The Company reviews certain identifiable intangibles for impairment whenever events or changes in circumstances indicate that the carrying amount of any such asset may not be recoverable. 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 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 form 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, 2015, we sold and disposed of eight light and six medium aircraft previously utilized in our Oil and Gas segment. The carrying value of these assets prior to the sale was $3.7 million. These assets were sold for $3.7 million, which resulted in no gain. These aircraft no longer met our strategic needs. We also sold the associated spare parts inventory for these aircraft, which resulted in a $0.3 million loss. During the twelve months ended December 31, 2014, we sold nine light and three fixed wing aircraft previously utilized in our Oil and Gas segment. The carrying value of these assets prior to the sale was $5.5 million. These assets were sold for $5.9 million, which resulted in a gain of $0.4 million. We also sold or disposed of one medium and four light aircraft previously utilized in our Air Medical segment. The carrying value of these assets prior to the sale was $10.8 million. These assets were sold for $8.2 million, resulting in a loss of $2.6 million. These aircraft no longer met our strategic needs. Sales and disposals of various ancillary equipment resulted in a gain of $1.4 million. Impairment Losses In connection with our normal recurring impairment testing, we recorded an impairment loss in the year ended December 31, 2014 for 13 medium aircraft in our Oil and Gas segment and one medium aircraft in our Air Medical segment. The carrying value of these aircraft was $16.5 million. Following a market analysis, we determined that the market value for these aircraft was $6.0 million. Similarly, we also recorded an impairment loss in the year ended 2013 for two medium aircraft in our Oil and Gas segment and two medium aircraft in our Air Medical segment. The carrying value of these aircraft was $4.0 million. Following a market analysis, we determined that the market value of these aircraft was $2.4 million. As a result of these analyses, we recorded aggregate non-cash pre-tax impairment losses of $10.5 million and $1.6 million for 2014 and 2013, respectively. We did not record an impairment loss in the year ended December 31, 2015. See Note 3 for additional information. 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, 2015. As of December 31, 2015 and 2014, the Company had $1.9 million and $1.7 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 $2.6 million and $2.5 million for the years 2015 and 2014, 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 $1.0 million and $0.9 million, respectively, to this captive company in 2015 and 2014, which were eliminated in consolidation. The results of the captive are fully consolidated in the accompanying consolidated financial statements. Revenue Recognition The Company recognizes revenue related to aviation transportation services after the services are performed or the contractual obligations are met. Aircraft maintenance services revenues are recognized at the time the repair or services work is completed. Revenues related to the Company’s Air Medical segment independent provider model services are recorded net of contractual allowances under agreements with third party payors, and also recorded net of uncompensated care allowances when the services are provided. Revenues generated under the traditional provider model consist of a fixed monthly rate for aircraft availability and an hourly rate for flight time. 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. The allowance for contractual discounts against outstanding accounts receivable was $103.6 million, $96.6 million, and $74.7 million as of December 31, 2015, 2014, and 2013, respectively. The allowance for uncompensated care against outstanding accounts receivable was $41.9 million, $41.9 million, and $46.4 million as of December 31, 2015, 2014, and 2013, 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 $9.3 million, $9.1 million, and $7.9 million for the years ended December 31, 2015, 2014, and 2013, respectively. The estimated cost of providing charity services was $2.0 million, $2.1 million, and $3.0 million for the years ended December 31, 2015, 2014, and 2013, 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 segment’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 by each individual 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 nine 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 segment billings) were as follows: Year Ended December 31, 2015 2014 2013 Provision for contractual discounts 65 % 72 % 60 % Provision for uncompensated care 8 % 2 % 10 % Amounts attributable to Medicaid, Medicare, private insurance, and self-pay as a percentage of net Air Medical revenues were as follows: Year Ended December 31, 2015 2014 2013 Insurance 74 % 74 % 73 % Medicare 17 % 18 % 19 % Medicaid 8 % 8 % 7 % Self-Pay 1 % 0 % 1 % Under a three-year 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 has been extended to June 29, 2016 on terms that have reduced the number of aircraft operated by us and the scope of our services and responsibilities. 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 are accounted for in accordance with the provisions of Accounting Standards Codification 740, Income Taxes 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 Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of trade accounts receivables. The Company does not believe significant credit risk existed with respect to these trade accounts receivable at December 31, 2015. 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 and U.S. governmental agencies. 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 in the Oil and Gas and Technical Services segments was $3.2 million and $0.1 million at December 31, 2015 and 2014, 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. The allowance for contractual discounts was $103.6 million, $96.6 million, and $74.7 million as of December 31, 2015, 2014, and 2013, respectively. The allowance for uncompensated care was $41.9 million, $41.9 million, and $46.4 million as of December 31, 2015, 2014, and 2013, respectively. The Company’s two largest oil and gas customers accounted for 26% of consolidated operating revenues for the year ended December 31, 2015, 30% for the year ended December 31, 2014, and 28% for the year ended December 31, 2013. The Company also carried accounts receivable from these same customers totaling 15% and 18% of net trade receivables on December 31, 2015 and 2014, respectively. The Company’s largest Air Medical customer accounted for 9% and 10% of consolidated operating revenues for the years ended December 31, 2015 and 2014, respectively. The Company also carried accounts receivable from this customer totaling 15% and 20% of net trade receivables on December 31, 2015 and 2014, 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. New Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers In August 2014, the FASB issued ASU 2014-15 Presentation of Financial Statements – Going Concern (Subtopic 205-40): of Uncertainties about an Entity’s Ability to Continue as a Going Concern In April 2015, the FASB issued ASU No. 2015-03, Simplifying the Presentation of Debt Issuance Costs. In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes

Investments

Investments	12 Months Ended
	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Investments	(2) 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, and in our consolidated statements of shareholders’ equity. Cost, gains, and losses are determined using the specific identification method. In the years ended December 31, 2015, 2014, and 2013, we received proceeds from the sales of these securities of $506.0 million, $363.1 million, and $339.0 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, 2015: Unrealized Unrealized Fair Cost Basis Gains Losses Value (Thousands of dollars) Investments: Money market mutual funds $ 18,181 $ — $ — $ 18,181 Commercial paper 5,986 — (5 ) 5,981 U.S. government agencies 11,499 — (30 ) 11,469 Corporate bonds and notes 265,069 — (841 ) 264,228 Subtotal 300,735 — (876 ) 299,859 Deferred compensation plan assets included in other assets 2,294 — — 2,294 Total $ 303,029 $ — $ (876 ) $ 302,153 $15.3 million of our investments at December 31, 2015 were long-term and included on the balance sheet as Restricted investments as they are securing outstanding letters of credit with maturities beyond one year. Investments consisted of the following as of December 31, 2014: Unrealized Unrealized Fair Cost Basis Gains Losses Value (Thousands of dollars) Investments: Money market mutual funds $ 68,612 $ — $ — $ 68,612 Municipal bonds and notes 1,500 2 — 1,502 Corporate bonds and notes 130,864 19 (268 ) 130,615 Subtotal 200,976 21 (268 ) 200,729 Deferred compensation plan assets included in other assets 2,386 — — 2,386 Total $ 203,362 $ 21 $ (268 ) $ 203,115 $15.5 million of our investments at December 31, 2014 were long-term and included on the balance sheet as Restricted 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, 2015 2014 Amortized Fair Amortized Fair Costs Value Costs Value (Thousands of dollars) Due in one year or less $ 152,444 $ 152,212 $ 70,180 $ 70,169 Due within two years 130,110 129,466 62,184 61,948 Total $ 282,554 $ 281,678 $ 132,364 $ 132,117 The following table presents the average coupon rate percentage and the average days to maturity of our debt investments as of December 31, 2015 2014 Average Average Average Average Coupon Days To Coupon Days To Rate (%) Maturity Rate (%) Maturity Commercial paper 0.553 154 n/a n/a U.S. government agencies 0.865 599 n/a n/a Municipal bonds and notes n/a n/a 0.528 134 Corporate bonds and notes 1.757 331 1.828 348 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, 2015 2014 Unrealized Unrealized Fair Value Losses Fair Value Losses (Thousands of dollars) Commercial paper $ 5,981 $ (5 ) $ — $ — U.S. government agencies 8,969 (30 ) — — Corporate bonds and notes 232,347 (793 ) 100,071 (268 ) Total $ 247,297 $ (828 ) $ 100,071 $ (268 ) 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, 2015 2014 Unrealized Unrealized Fair Value Losses Fair Value Losses (Thousands of dollars) Corporate bonds and notes $ 28,866 $ (48 ) $ — $ — Total $ 28,866 $ (48 ) $ — $ — As noted above, from time to time over the periods covered in our financial statements included herein, our investments have experienced net unrealized losses. We consider these declines in market value to be due to market conditions, and we do not plan to sell these investments prior to maturity. For these reasons, we do not consider any of our investments to be other than temporarily impaired at December 31, 2015 and 2014. The assessment of whether an investment in a debt security has suffered an other-than-temporary impairment is based on whether the Company has the intent to sell or more likely than not will be required to sell the debt security before recovery of its amortized costs. Further, if the Company does not expect to recover the entire amortized cost basis of the debt security, an other-than-temporary impairment is considered to have occurred and it is measured by the present value of cash flows expected to be collected less the amortized cost basis (credit loss). The Company determined it did not have any other-than-temporary impairments relating to credit losses on debt securities for the year ended December 31, 2015 or 2014.

Fair Value

Fair Value	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value	(3) 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, 2015 Total (Level 1) (Level 2) Investments: Money Market Mutual Funds $ 18,181 $ 18,181 $ — Commercial Paper 5,981 — 5,981 U.S. Government Agencies 11,469 — 11,469 Corporate bonds and notes 264,228 — 264,228 299,859 18,181 281,678 Deferred compensation plan assets 2,294 2,294 — Total $ 302,153 $ 20,475 $ 281,678 December 31, 2014 Total (Level 1) (Level 2) Investments: Money Market Mutual Funds $ 68,612 $ 68,612 $ — Municipal bonds and notes 1,502 — 1,502 Corporate bonds and notes 130,615 — 130,615 200,729 68,612 132,117 Deferred compensation plan assets 2,386 2,386 — Total $ 203,115 $ 70,998 $ 132,117 The Company holds its 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 shares of 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 active. These items may not be traded daily; examples include corporate bonds and U.S. government agencies. Assets are valued based on prices derived by independent third parties that use inputs such as benchmark yields, reported trades, broker/dealer quotes, and issuer spreads. Prices are reviewed and can be challenged with the independent parties and/or overridden by the Company, if it is believed such would be more reflective of fair value. Investments included in other assets, which relate to the liability for the Officers’ Deferred Compensation Plan, consist mainly of multiple investment funds that are highly liquid and diversified. Cash, accounts receivable, accounts payable and accrued liabilities all had fair values approximating their carrying amounts at December 31, 2015 and 2014. In connection with its impairment testing (discussed further in Note 1), the Company estimates cash flows 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, the Company uses the discounted cash flow method to determine the estimated fair value of each asset group and compares such estimated fair value to the book value of each asset group in order to determine if impairment exists. If impairment exists, the book value of the asset group is reduced to its estimated fair value. The below table summarizes the combined fair value of the assets that incurred impairments during the years ended December 31, 2015 and 2014, along with the amount of the impairment. The impairment charges were recorded in Impairment of assets. Year Ended December 31, 2015 2014 (Thousands of dollars) Amount of impairment incurred $ — $ 10,508 Combined fair value of assets incurring impairment $ — $ 6,000

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Property and Equipment	(4) PROPERTY AND EQUIPMENT The following table summarizes the Company’s property and equipment at December 31 of the following years: 2015 2014 (Thousands of dollars) Flight equipment $ 1,096,986 $ 1,053,640 Facility & improvements 61,330 61,246 Operating equipment 26,004 24,764 Data processing equipment 33,178 32,374 Vehicles 8,461 8,133 Medical equipment 7,514 7,377 Other 5,377 5,332 1,238,850 1,192,866 Less accumulated depreciation and amortization (355,321 ) (315,048 ) Property and equipment, net $ 883,529 $ 877,818 Depreciation expense related to property and equipment was $46.7 million in 2015, $43.7 million in 2014, and $38.9 million in 2013. 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, 2015
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets	(5) OTHER ASSETS The following table summarizes the Company’s other assets at December 31 of the following years: 2015 2014 (Thousands of dollars) Deposits on future purchases of aircraft $ 3,568 $ 8,305 Deferred financing cost 3,999 5,246 Investments (Officers’ Deferred Compensation Plan) 2,294 2,386 Other 316 316 Total $ 10,177 $ 16,253

Accrued and Other Current Liabi

Accrued and Other Current Liabilities	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Accrued and Other Current Liabilities	(6) ACCRUED AND OTHER CURRENT LIABILITIES Accrued and other current liabilities as of December 31 consisted of the following: 2015 2014 (Thousands of dollars) Salaries & wages $ 19,955 $ 16,203 Incentive compensation 2,819 11,730 Income taxes 1,453 3,787 Interest 7,925 7,891 Vacation payable 5,801 6,112 Group medical 1,944 1,735 Transportations tax 892 907 Operating lease 814 1,227 Workers compensation 1,047 1,185 Other 2,109 2,035 Total accrued liabilities $ 44,759 $ 52,812

Long Term Debt

Long Term Debt	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Long Term Debt	(7) LONG-TERM DEBT The components of long-term debt as of December 31 are as follows: 2015 2014 (Thousands of dollars) Senior Notes issued March 17, 2014, interest only payable semi-annually at 5.25%, maturing March 15, 2019 $ 500,000 $ 500,000 Revolving Credit Facility due October 1, 2017 with a group of commercial banks, interest payable at variable rates 57,500 43,000 Total long-term debt $ 557,500 $ 543,000 Listed below is information on our future annual maturities of long-term debt (in thousands): 2016 $ — 2017 57,500 2018 — 2019 500,000 2020 — Thereafter — Total $ 557,500 Senior Notes Proceeds from our sale of the Notes in 2014 were approximately $493.8 million, net of fees and expenses, and were used to retire all of our $300 million of previously outstanding 8.625% Senior Notes pursuant to a tender offer, at a total cost of $329.4 million, including the tender premium and accrued interest. As a result of our repurchase of 8.625% Senior Notes in 2014, we recorded a pretax charge of $29.8 million, which consisted of $26.7 million of premium and $3.1 million of unamortized issuance costs. The Notes bear interest at a fixed rate and therefore changes in market interest rates do not affect our interest payment obligations on the notes. The fair market value of the Notes varies as changes occur to general market interest rates, the remaining maturity of the notes, and our credit worthiness. At December 31, 2015, the fair market value of the Notes was $403.1 million, and the carrying value was $500 million. At December 31, 2014, the fair market value of Notes was $425.6 million and the carrying value was $500 million. Revolving Credit Facility For additional information on our revolving credit facility, see “Management’s Discussion and Analysis of Financial Condition and Results of Operations – Liquidity and Capital Resources – Long Term Debt” included in Item 7 of this report. Other -

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	(8) INCOME TAXES Income tax expense is composed of the following: Year Ended December 31, 2015 2014 2013 (Thousands of dollars) Current Federal $ — $ — $ — State 284 307 353 Foreign 3,159 4,352 9,637 Deferred – principally Federal 12,889 15,768 21,195 Total $ 16,332 $ 20,427 $ 31,185 Income tax expense as a percentage of pre-tax earnings varies from the effective Federal statutory rate of 35% as a result of the following: Year Ended Year Ended Year Ended December 31, December 31, December 31, (Thousands of dollars, except percentage amounts) Amount Tax Amount Tax Amount Tax Income taxes at statutory rate $ 15,140 35 $ 18,590 35 $ 31,550 35 Increase (decrease) in taxes resulting from: Valuation allowance on foreign tax credits — — 113 — — — Valuation allowance reversal–investment in foreign entity (456 ) (1 ) — — — — Change in tax rate on deferred items 1,078 3 — — (3,850 ) (4 ) State income taxes, net of federal benefit 146 — 916 2 2,161 2 Other items – net 424 1 808 1 1,324 2 Total $ 16,332 38 $ 20,427 38 $ 31,185 35 The change in tax rate on deferred items relates to the increase in the estimated effective tax rate that will be present at the time the deferred tax assets and liabilities reverse for tax purposes. The increase is attributable to an increase in the apportionment percentages in the various jurisdictions in which we operate as a result of increased operations in certain states. 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: 2015 2014 (Thousands of dollars) Deferred tax assets: Deferred compensation $ 946 $ 1,023 Foreign tax credits 20,118 16,982 Vacation and bonus accrual 1,952 2,031 Inventory valuation 6,808 6,093 Rental accrual 1,691 1,799 Hurricane relief credit 1,255 1,255 Stock-based compensation 3,598 2,977 Other 3,593 2,714 Net operating losses 61,611 56,305 Total deferred tax assets 101,572 91,179 Valuation allowance – state NOL carryforwards (290 ) (219 ) Valuation allowance – tax credit carryforwards (2,047 ) (2,047 ) Valuation allowance – other — (1,466 ) Total deferred tax assets, net 99,235 87,447 Deferred tax liabilities: Tax depreciation in excess of book depreciation (242,501 ) (218,064 ) Total deferred tax liabilities (242,501 ) (218,064 ) Net deferred tax liabilities $ (143,266 ) $ (130,617 ) Current deferred tax assets $ 10,379 $ 9,915 Deferred tax liability – long-term (153,645 ) (140,532 ) Net deferred tax liabilities $ (143,266 ) $ (130,617 ) As a result of certain realization requirements under GAAP, the Company’s deferred tax assets as of December 31, 2015 in the table above do not include certain deferred tax assets that arose directly from tax deductions related to equity compensation in excess of compensation recognized for financial reporting. Equity is expected to increase by $1.0 million when the deferred tax assets are ultimately realized. The Company uses tax law ordering for purposes of determining when excess tax benefits have been realized. The Company has U.S. Federal net operating loss carryforwards (“NOLs”) of approximately $158.3 million that, if not used, will expire beginning in 2028 through 2035. Additionally, for state income tax purposes, the Company has NOLs of approximately $160.4 million available to reduce future state taxable income. These NOLs expire in varying amounts through 2035, the majority of which expire in 2024 through 2035. The Company has a valuation allowance of $0.3 million as of December 31, 2015 against certain net operating losses in nine states which we have determined are more likely than not to be forfeited in future years. During 2015, the Company recorded $0.1 million of valuation allowances on state NOLs. The Company also has foreign tax credits of approximately $20.1 million which expire beginning in 2016 through 2025. 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 $2.0 million on these credits, of which of $-0- million was recorded in 2015 . The Company files income tax returns in the U.S. federal jurisdiction and in many U.S. state jurisdictions. The tax years 2012 to 2015 remain open to examination by the major taxing jurisdictions in which the Company is subject to tax. Income taxes paid were approximately $5.5 million, $9.6 million, and $1.1 million for each of the years ended December 31, 2015, 2014, and 2013, respectively. At December 31, 2015, 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, 2015
Earnings Per Share [Abstract]
Earnings Per Share	(9) EARNINGS PER SHARE The components of basic and diluted earnings per share for the years ended December 31, are as follows: 2015 2014 2013 (in thousands) Weighted average outstanding shares of common stock, basic 15,566 15,483 15,474 Dilutive effect of restricted stock units 76 202 165 Weighted average outstanding shares of common stock, diluted 15,642 15,685 15,639 There were no shares of stock that were anti-dilutive to earnings for the years ended December 31, 2015, 2014, and 2013.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2015
Postemployment Benefits [Abstract]
Employee Benefit Plans	(10) 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 $2.3 million and $2.4 million for the years ended December 31, 2015 and 2014, respectively. Incentive Compensation The Company has three different incentive compensation plans. The incentive compensation plan for non-executive employees allows the Company to pay up to 8.25% of earnings before tax 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 Company’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 accrued incentive compensation expense of $3.0 million, $11.7 million, and $11.5 million for the years ended December 31, 2015, 2014, and 2013, respectively. We also have a Safety Incentive Plan related to Occupational Safety and Health Administration recordable incidents, for which we expensed and paid $0.9 million, $1.0 million, and $1.0 million for the years 2015, 2014, and 2013, respectively. 401(k) 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, 2015, 2014, and 2013 were $11.8 million, $11.5 million, and $10.5 million, respectively.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	(11) STOCK-BASED COMPENSATION Compensation expense for our stock-based plans was $5.8 million, $4.8 million, and $2.4 million for 2015, 2014, and 2013, respectively. 2012 Long-Term Incentive Plan Non-Voting Time-Vested Restricted Stock Units Share Units Weighted Grant-Date Remaining (in years) Aggregate Value (in thousands) Outstanding at January 1, 2015 191,655 $ 38.56 2.26 $ 7,391 Granted 35,456 30.17 Forfeited (8,026 ) (22.81 ) Vested and released to participants (37,610 ) (24.82 ) Outstanding at December 31, 2015 181,475 $ 40.47 1.56 $ 7,344 The weighted average grant-date fair value of time-vested restricted stock units granted during 2015 and 2014 was $30.17 and $43.25 per share, respectively. The total fair value of awards that vested in 2015 was $0.9 million. The total fair value of awards that vested in 2014 was $0.3 million. The total fair value of awards forfeited in 2015 was $0.2 million. There were no forfeitures in 2014. As of December 31, 2015, there was $3.4 million that is expected to be recognized over a weighted average period of 1.56 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, 2015. Share Units Weighted Grant-Date Remaining Aggregate Value Outstanding at January 1, 2015 4,488 $ 41.19 2.48 $ 185 Granted 4,317 21.42 Forfeited — — Vested and released to participants — — Outstanding at December 31, 2015 8,805 $ 31.50 2.21 $ 277 Non-Voting -Based Restricted Stock Units Share Units Weighted Grant-Date Remaining (in years) Aggregate Value (in thousands) Outstanding at January 1, 2015 394,669 $ 30.07 1.78 $ 11,878 Granted 152,331 33.41 Forfeited (10,758 ) (22.81 ) Vested and released to participants (141,286 ) (23.04 ) Outstanding at December 31, 2015 394,956 $ 34.07 1.83 $ 13,456 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 weighted average grant-date fair value of performance based restricted stock units granted during 2015 was $33.41 per share. The total fair value of awards that vested in 2015 was $3.3 million. Total fair value of awards forfeited in 2015 was $0.2 million. As of December 31, 2015, there was a total of $7.4 million of unrecognized compensation cost related to the non-vested performance-based restricted stock units that is expected to be recognized over a weighted average period of 1.83 years.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	(12) 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 December 31, December 31, December 31, 2015 2014 2013 (Thousands of dollars) Aircraft $ 45,360 $ 44,908 $ 41,803 Other 8,358 7,790 7,657 Total $ 53,718 $ 52,698 $ 49,460 Included in the above rental expense is $-0- million in 2015, $0.5 million in 2014, and $0.6 million in 2013 paid to GE Air, Inc. and Gonsoulin Enterprises, Inc. for the lease of aircraft and real estate. Each of GE Air, Inc. and Gonsoulin Enterprises, Inc. is owned by our Chairman, CEO and majority voting shareholder. The following table presents the 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) 2016 $ 44,988 $ 5,305 $ 50,293 2017 42,699 3,193 45,892 2018 39,018 2,552 41,570 2019 32,365 1,983 34,348 2020 28,526 1,413 29,939 Thereafter 89,604 745 90,349 $ 277,200 $ 15,191 $ 292,391 Purchase Options In 2015, we purchased one heavy aircraft pursuant to a purchase option in the lease contract for an aggregate purchase price of $17.7 million using proceeds from the sale of short-term investments. As of December 31, 2015, we had options to purchase aircraft under lease becoming exercisable in 2016 through 2020 for the following aggregate purchase prices: $67.8 million in 2016, $55.7 million in 2017, $127.0 million in 2018, $150.4 million in 2019, and $22.7 million in 2020. Whether we exercise these 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, 2015 was $1.1 million. Purchase Commitments In 2014, we exercised an option to purchase six additional heavy aircraft for delivery in 2015 and 2016. In 2015, we executed an amendment to terminate the order of four of the heavy aircraft for delivery in 2016. We took delivery of one aircraft in 2015 and expect to take delivery of the final aircraft in the second quarter of 2016. Total aircraft deposits of $3.6 million were included in Other Assets as of December 31, 2015. This amount represents deposits for aircraft purchase contracts and deposits on future lease buyout options. In the event the buyout options are not exercised, the deposits will be applied as lease payments. Environmental Matters We have recorded an aggregate estimated probable liability of $0.2 million as of December 31, 2015 for environmental response costs. We have conducted environmental surveys of our former Lafayette facility located at the Lafayette Regional Airport, which we vacated in 2001, and have determined that limited soil and groundwater contamination exists at two parcels of land at the former facility. We submitted an assessment report for both sites in 2003, updated it in 2006, and received approvals of our remediation plan from the Louisiana Department of Environmental Quality (“LDEQ”) and Louisiana Department of Natural Resources in 2010 and 2011, respectively. Since such time, we have installed groundwater monitoring wells at these sites and furnished periodic reports on contamination levels to the LDEQ. Pursuant to our agreement with the LDEQ, we were providing samples twice a year for both sites and plan to remove underground storage tanks under one of the sites later this year. In response to our request, LDEQ has approved annual sampling from 2015 to 2019, followed by reevaluation of the sampling frequency. Based upon our working relationships and agreements with the LDEQ and the results of our ongoing site monitoring, we believe, based on current circumstances, that our ultimate remediation costs for these sites will not be material to our consolidated financial position, results of operations, or cash flows. Legal Matters 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, 2015
Segment Reporting [Abstract]
Business Segments and Geographic Areas	(13) BUSINESS SEGMENTS AND GEOGRAPHIC AREAS PHI is primarily a provider of helicopter services, including helicopter maintenance and repair services. The Company has used a combination of factors to identify its reportable segments as required by Accounting Standards Codification 280, “Segment Reporting.” The overriding determination of the Company’s segments is based on how the chief operating decision-maker of the Company, the Chairman of the Board and Chief Executive Officer, evaluates the Company’s results of operations. The underlying factors include customer bases, types of service, operational management, physical locations, and underlying economic characteristics of the types of work the Company performs. A segment’s operating profit 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. The Oil and Gas segment provides helicopter services to oil and gas customers operating in the Gulf of Mexico and two foreign countries. The Air Medical segment provides helicopter services to hospitals and medical programs in several U.S. states, one foreign country, 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 flight 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 Operating Revenues December 31, Years Ended December 31, 2015 2014 2015 2014 2013 Oil and Gas segment: Customer A 6 % 7 % 15 % 17 % 15 % Customer B 9 % 12 % 11 % 13 % 13 % Air Medical & Technical Services segments: Customer C 15 % 20 % 9 % 10 % 17 % 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, 2015, 2014, and 2013. 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 the 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, 2015 2014 2013 (Thousands of dollars) Segment operating revenues Oil and Gas $ 459,611 $ 516,909 $ 489,055 Air Medical 312,775 300,212 277,884 Technical Services 31,842 19,149 89,561 Total operating revenues 804,228 836,270 856,500 Segment direct expenses Oil and Gas (1) 411,757 411,679 393,251 Air Medical 246,487 243,573 231,880 Technical Services 29,112 14,851 88,221 Total segment direct expenses 687,356 670,103 713,352 Segment selling, general and administrative expenses Oil and Gas 6,511 4,615 4,059 Air Medical (2) 10,455 9,801 8,875 Technical Services 805 157 1 Total segment selling, general and administrative expenses 17,771 14,573 12,935 Total segment expenses 705,127 684,676 726,287 Net segment profit Oil and Gas 41,343 100,615 91,745 Air Medical 55,833 46,838 37,129 Technical Services 1,925 4,141 1,339 Total 99,101 151,594 130,213 Other, net (3) 1,872 (10,539 ) 15,569 Unallocated selling, general and administrative expenses (28,651 ) (28,597 ) (26,207 ) Interest expense (29,066 ) (29,510 ) (29,434 ) Loss on debt extinguishment — (29,833 ) — Earnings before income taxes $ 43,256 $ 53,115 $ 90,141 (1) Includes equity in loss of unconsolidated affiliate. (2) Includes interest expense $0.3 million for the year ended December 31, 2013. (3) Includes gains on disposition of property and equipment and other income. Year Ended December 31, 2015 2014 2013 (Thousands of dollars) Expenditures for long-lived assets Oil and Gas $ 32,501 $ 119,235 $ 62,934 Air Medical 22,685 37,317 37,728 Corporate 1,389 1,153 1,928 Total $ 56,575 $ 157,705 $ 102,590 Year Ended December 31, 2015 2014 2013 (Thousands of dollars) Depreciation and Amortization Oil and Gas $ 42,709 $ 29,635 $ 26,653 Air Medical 18,177 13,067 11,395 Technical Services 518 493 172 Corporate 10,214 7,653 4,628 Total $ 71,618 $ 50,848 $ 42,848 Assets Oil and Gas $ 704,472 $ 726,008 Air Medical 329,484 336,510 Technical Services 7,345 7,842 Corporate 389,031 305,720 Total $ 1,430,332 $ 1,376,080 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, 2015 2014 2013 (Thousands of dollars) Operating revenues: United States $ 722,339 $ 747,063 $ 699,298 International 81,889 89,207 157,202 Total $ 804,228 $ 836,270 $ 856,500 Long-Lived Assets: United States $ 773,939 $ 846,377 International 109,590 31,441 Total $ 883,529 $ 877,818 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. For additional information on the risks of operating internationally, see our risk factor disclosures contained in Item 1A of this Form 10-K.

Quarterly Financial Data (Unaud

Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data (Unaudited)	(14) QUARTERLY FINANCIAL DATA (UNAUDITED) The condensed quarterly results of operations for the years ended December 31, 2015 and 2014 (in thousands of dollars, except per share data) were as follows: Quarter Ended March 31, June 30, September 30, December 31, 2015 2015 2015 2015 (Thousands of dollars, except per share data) Operating revenues $ 204,197 $ 198,547 $ 214,733 $ 186,751 Gain (loss) on disposition of assets, net 7 66 165 (577 ) Earnings (loss) before income taxes 16,984 11,044 14,290 938 Net earnings 10,363 6,454 7,669 2,438 Net earnings per share Basic 0.67 0.41 0.49 0.16 Diluted 0.66 0.41 0.49 0.16 Quarter Ended March 31, June 30, September 30, December 31, 2014 2014 2014 2014 (Thousands of dollars, except per share data) Operating revenues, net $ 197,071 $ 212,145 $ 216,294 $ 210,760 Gain (loss) on disposition of assets, net (1,073 ) (242 ) (56 ) 523 Earnings (loss) before income taxes (8,513 ) 21,700 28,277 11,651 Net earnings (loss) (5,321 ) 13,368 17,249 7,392 Net earnings (loss) per share Basic (0.34 ) 0.86 1.11 0.48 Diluted (0.34 ) 0.85 1.10 0.47

Variable Interest Entity

Variable Interest Entity	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Variable Interest Entity	(15) VARIABLE INTEREST ENTITY We account for our West African operations 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, 2015, we had a 49% investment in the common stock of PHI Century Limited (“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, 2015, we recorded a loss in equity of unconsolidated affiliate of $0.3 million relative to our 49% equity ownership. We had $1.5 million of Trade receivables as of December 31, 2015 from PHIC. At December 31, 2015, we recorded an allowance for bad debts against this trade receivables of $1.5 million as we do not anticipate that we will be able to recover them, For the year ended December 31, 2014, we recorded earnings in equity of unconsolidated affiliate of $0.1 million relative to our 49% equity ownership. In addition, we had $2.8 million of Trade receivables and $0.9 million accrued liabilities as of December 31, 2014 from PHIC. Our investment in the common stock of PHIC is included in Other assets on our Condensed Consolidated Balance Sheet and was $-0- million at December 31, 2015 and December 31, 2014. Included in Operating revenues for the years ended December 31, 2015 and December 31, 2014 was $-0- million and $3.4 million of revenues from services provided to PHIC, respectively.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	(16) SUBSEQUENT EVENTS Following three earlier programs in 2015, in January, 2016, we implemented a fourth voluntary employee retirement program (“VERP”) offered to all pilots who have attained age 64. The employees have until February 28, 2016 to accept the offer. Our maximum severance cost exposure under this program is $3.1 million. We also implemented a voluntary furlough program to our oil and gas pilots whereby pilots who elect to participate in the program will receive severance pay and may continue their medical coverage at their current employee-paid premiums. The period for acceptance of the furlough ended on January 27, 2016. Twenty-six pilots accepted the offer with a total severance cost of $0.4 million. Under the terms of the furlough agreement, PHI may provide notice of recall to the employees back to full-time employment no later than November 17, 2016.

Condensed Consolidating Financi

Condensed Consolidating Financial Information - Guarantor Subsidiaries	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Condensed Consolidating Financial Information - Guarantor Subsidiaries	(17) CONDENSED CONSOLIDATING FINANCIAL INFORMATION – GUARANTOR SUBSIDIARIES Our 5.25% Senior Notes are fully and unconditionally guaranteed on a joint and several, senior basis by all of our domestic subsidiaries. All of our domestic subsidiaries are 100% owned. The following supplemental condensed financial information 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 Only”) and the guarantor subsidiaries. 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 these condensed consolidating financials. 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, are large, 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. PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS (Thousands of dollars) December 31, 2015 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated ASSETS Current Assets: Cash $ 46 $ 2,361 $ — $ 2,407 Short-term investments 284,523 — — 284,523 Accounts receivable – net 70,336 74,442 — 144,778 Intercompany receivable — 90,943 (90,943 ) — Inventories of spare parts – net 60,060 9,431 — 69,491 Prepaid expenses 7,162 1,789 — 8,951 Deferred income taxes 10,379 — — 10,379 Income taxes receivable 1,002 (241 ) — 761 Total current assets 433,508 178,725 (90,943 ) 521,290 Investment in subsidiaries 330,848 — (330,848 ) — Property and equipment, net 632,759 250,770 — 883,529 Restricted investments 15,336 — — 15,336 Other assets 9,974 203 — 10,177 Total assets $ 1,422,425 $ 429,698 $ (421,791 ) $ 1,430,332 LIABILITIES AND SHAREHOLDERS’ EQUITY Current Liabilities: Accounts payable $ 25,512 $ 5,861 $ — $ 31,373 Accrued liabilities 29,138 15,621 — 44,759 Intercompany payable 90,943 — (90,943 ) — Total current liabilities 145,593 21,482 (90,943 ) 76,132 Long-term debt 557,500 — — 557,500 Deferred income taxes and other long-term liabilities 92,334 77,368 — 169,702 Shareholders’ Equity: Common stock and paid-in capital 306,444 79,061 (79,061 ) 306,444 Accumulated other comprehensive loss (567 ) — — (567 ) Retained earnings 321,121 251,787 (251,787 ) 321,121 Total shareholders’ equity 626,998 330,848 (330,848 ) 626,998 Total liabilities and shareholders’ equity $ 1,422,425 $ 429,698 $ (421,791 ) $ 1,430,332 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. December 31, 2014 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated ASSETS Current Assets: Cash $ 51 $ 6,219 $ — $ 6,270 Short-term investments 185,244 — — 185,244 Accounts receivable – net 98,001 82,760 — 180,761 Intercompany receivable — 95,399 (95,399 ) — Inventories of spare parts – net 65,341 8,452 — 73,793 Prepaid expenses 7,610 1,704 — 9,314 Deferred income taxes 9,915 — — 9,915 Income taxes receivable 1,068 159 — 1,227 Total current assets 367,230 194,693 (95,399 ) 466,524 Investment in subsidiaries and others 358,080 — (358,080 ) — Property and equipment, net 638,437 239,381 — 877,818 Restricted investments 15,485 — — 15,485 Other assets 16,055 198 — 16,253 Total assets $ 1,395,287 $ 434,272 $ (453,479 ) $ 1,376,080 LIABILITIES AND SHAREHOLDERS’ EQUITY Current Liabilities: Accounts payable $ 22,578 $ 5,122 $ — $ 27,700 Accrued and other current liabilities 34,477 18,335 — 52,812 Intercompany payable 95,270 — (95,270 ) — Total current liabilities 152,325 23,457 (95,270 ) 80,512 Long-term debt 543,000 — — 543,000 Deferred income taxes and other long-term liabilities 102,894 52,606 — 155,500 Shareholders’ Equity: Common stock and paid-in capital 303,082 137,647 (137,647 ) 303,082 Accumulated other comprehensive loss (211 ) — — (211 ) Retained earnings 294,197 220,562 (220,562 ) 294,197 Total shareholders’ equity 597,068 358,209 (358,209 ) 597,068 Total liabilities and shareholders’ equity $ 1,395,287 $ 434,272 $ (453,479 ) $ 1,376,080 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Thousands of dollars) For the year ended December 31, 2015 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated Operating revenues, net $ 476,969 $ 327,259 $ — $ 804,228 Expenses: Direct expenses 426,239 260,829 (18 ) 687,050 Selling, general, and administrative expenses 35,694 10,728 — 46,422 Total operating expenses 461,933 271,557 (18 ) 733,472 Loss on disposition of assets, net 339 — — 339 Equity in loss of unconsolidated affiliate 306 — — 306 Operating income 14,391 55,702 18 70,111 Equity in net earnings of consolidated subsidiaries (31,225 ) — 31,225 — Interest expense 28,946 120 — 29,066 Other income, net (2,222 ) (7 ) 18 (2,211 ) (4,501 ) 113 31,243 26,855 Earnings before income taxes 18,992 55,589 (31,225 ) 43,256 Income tax expense (8,032 ) 24,364 — 16,332 Net earnings $ 26,924 $ 31,225 $ (31,225 ) $ 26,924 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. For the year ended December 31, 2014 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated Operating revenues, net $ 504,180 $ 332,090 $ — $ 836,270 Expenses: Direct expenses 411,398 258,627 (18 ) 670,007 Selling, general, and administrative expenses 32,985 10,186 — 43,171 Total operating expenses 444,383 268,813 (18 ) 713,178 Loss on disposition of assets, net 848 — — 848 Impairment of assets 10,508 — — 10,508 Equity in loss of unconsolidated affiliate 96 — — 96 Operating income 48,345 63,277 18 111,640 Equity in net earnings of consolidated subsidiaries (38,740 ) — 38,740 — Interest expense 29,510 — — 29,510 Loss on debt extinguishment 29,833 — — 29,833 Other (income) expense, net (819 ) (17 ) 18 (818 ) 19,784 (17 ) 38,758 58,525 Earnings before income taxes 28,561 63,294 (38,740 ) 53,115 Income tax (benefit) expense (4,127 ) 24,554 — 20,427 Net earnings $ 32,688 $ 38,740 $ (38,740 ) $ 32,688 For the year ended December 31, 2013 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated Operating revenues, net $ 564,445 $ 292,055 $ — $ 856,500 Expenses: Direct expenses 468,321 244,769 — 713,090 Selling, general, and administrative expenses 29,885 8,935 — 38,820 Management fees (11,682 ) 11,682 — — Total operating expenses 486,524 265,386 — 751,910 (Gain) on disposition of assets, net (16,585 ) (19 ) — (16,604 ) Impairment of assets 1,227 421 — 1,648 Equity in loss of unconsolidated affiliate 262 — — 262 Operating income 93,017 26,267 — 119,284 Equity in net earnings of consolidated subsidiaries (15,567 ) — 15,567 — Interest expense 29,434 322 — 29,756 Other income, net (613 ) — — (613 ) 13,254 322 15,567 29,143 Earnings before income taxes 79,763 25,945 (15,567 ) 90,141 Income tax expense 20,807 10,378 — 31,185 Net earnings $ 58,956 $ 15,567 $ (15,567 ) $ 58,956 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (Thousands of dollars) For the year ended December 31, 2015 Parent Company Guarantor Only Subsidiaries (1) Eliminations Consolidated Net earnings $ 26,924 $ 31,225 $ (31,225 ) $ 26,924 Unrealized gain (loss) on short-term investments (641 ) — — (641 ) Other unrealized gain (loss) 24 — — 24 Changes in pension plan assets and benefit obligations 7 — — 7 Tax impact 254 — — 254 $ 26,568 $ 31,225 $ (31,225 ) $ 26,568 For the year ended December 31, 2014 Parent Company Guarantor Only Subsidiaries (1) Eliminations Consolidated Net earnings $ 32,688 $ 38,740 $ (38,740 ) $ 32,688 Unrealized gain (loss) on short-term investments (285 ) — — (285 ) Other unrealized gain (loss) (24 ) — — (24 ) Changes in pension plan assets and benefit obligations 17 — — 17 Tax impact 105 — — 105 $ 32,501 $ 38,740 $ (38,740 ) $ 32,501 For the year ended December 31, 2013 Parent Company Guarantor Only Subsidiaries (1) Eliminations Consolidated Net earnings $ 58,956 $ 15,567 $ (15,567 ) $ 58,956 Unrealized gain (loss) on short-term investments 44 — — 44 Changes in pension plan assets and benefit obligations (2 ) — — (2 ) Tax impact (15 ) — — (15 ) $ 58,983 $ 15,567 $ (15,567 ) $ 58,983 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS (Thousands of dollars) For the year ended December 31, 2015 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated Net cash provided by operating activities $ 60,241 $ 73,677 $ — $ 133,918 Investing activities: Purchase of property and equipment (57,123 ) — — (57,123 ) Proceeds from asset dispositions 5,236 — — 5,236 Purchase of short-term investments (608,649 ) — — (608,649 ) Proceeds from sale of short-term investments 505,966 — — 505,966 Payments of deposits on aircraft (1,273 ) — — (1,273 ) Refunds on deposits on aircraft 6,010 — — 6,010 Net cash used in investing activities (149,833 ) — — (149,833 ) Financing activities: Repurchase of common stock (2,448 ) (2,448 ) Proceeds on line of credit 232,660 — — 232,660 Payments on line of credit (218,160 ) — — (218,160 ) Due to/from affiliate, net 77,535 (77,535 ) — — Net cash provided by financing activities 89,587 (77,535 ) — 12,052 Decrease in cash (5 ) (3,858 ) — (3,863 ) Cash, beginning of year 51 6,219 — 6,270 Cash, end of year $ 46 $ 2,361 $ — $ 2,407 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. For the year ended December 31, 2014 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated Net cash provided by operating activities $ 51,476 $ 68,043 $ — $ 119,519 Investing activities: Purchase of property and equipment (157,690 ) — — (157,690 ) Proceeds from asset dispositions 10,266 — — 10,266 Purchase of short-term investments (465,094 ) — — (465,094 ) Proceeds from sale of short-term investments 363,110 — — 363,110 Refund of deposits on aircraft 11,506 — — 11,506 Payments of deposits on aircraft (6,948 ) — — (6,948 ) Loan to unconsolidated affiliate (200 ) — — (200 ) Net cash used in investing activities (245,050 ) — — (245,050 ) Financing activities: Proceeds from issuance of Senior Notes due 2019 500,000 — — 500,000 Repayment of Senior Notes due 2018 (300,000 ) — — (300,000 ) Premium and cost to retire debt early (26,749 ) — — (26,749 ) Debt issuance costs (6,232 ) — — (6,232 ) Proceeds from line of credit 264,253 — — 264,253 Payments on line of credit (300,253 ) — — (300,253 ) Repurchase of common stock (152 ) — — (152 ) Due to/from affiliate, net 62,706 (62,706 ) — — Net cash provided by financing activities 193,573 (62,706 ) — 130,867 (Decrease) increase in cash (1 ) 5,337 — 5,336 Cash, beginning of year 52 882 — 934 Cash, end of year $ 51 $ 6,219 $ — $ 6,270 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. For the year ended December 31, 2013 Parent Company Guarantor Only (issuer) Subsidiaries (1) (2) Eliminations Consolidated Net cash provided by operating activities $ 82,660 $ 22,436 $ — $ 105,096 Investing activities: Purchase of property and equipment (102,726 ) — — (102,726 ) Proceeds from asset dispositions 42,197 — — 42,197 Purchase of short-term investments (375,503 ) — — (375,503 ) Proceeds from sale of short-term investments 338,970 — — 338,970 Payments of deposits on aircraft (9,318 ) — — (9,318 ) Refunds on deposits on aircraft 8,161 — — 8,161 Net cash used in investing activities (98,219 ) — — (98,219 ) Financing activities: Repurchase of common stock (1,037 ) (1,037 ) Proceeds on line of credit 164,771 — — 164,771 Payments on line of credit (172,526 ) — — (172,526 ) Due to/from affiliate, net 23,851 (23,851 ) — — Net cash provided by financing activities 15,059 (23,851 ) — (8,792 ) Decrease in cash (500 ) (1,415 ) — (1,915 ) Cash, beginning of year 552 2,297 — 2,849 Cash, end of year $ 52 $ 882 $ — $ 934 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. (2) Cash flows between the Parent Company and guarantor subsidiaries related to the Company’s centralized cash management activities in 2013 have been adjusted to show the effects on net cash provided by operating and financing activities.

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Consolidated Accounts	12 Months Ended
	Dec. 31, 2015
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 Charged to Balance at Beginning Costs and End Description of Year Expenses Deductions (1) of Year Year ended December 31, 2015: Allowance for doubtful accounts $ 1,351 $ 3,800 $ — $ 5,151 Allowance for inventory 13,517 1,868 — 15,385 Allowance for contractual discounts 96,590 439,991 432,980 103,601 Allowance for uncompensated care 41,858 84,470 84,404 41,924 Year ended December 31, 2014: Allowance for doubtful accounts $ 1,001 $ 350 $ — $ 1,351 Allowance for inventory 12,292 1,225 — 13,517 Allowance for contractual discounts 74,711 408,362 386,483 96,590 Allowance for uncompensated care 46,387 79,564 84,093 41,858 Year ended December 31, 2013: Allowance for doubtful accounts $ 50 $ 951 $ — $ 1,001 Allowance for inventory 12,361 — 69 12,292 Allowance for contractual discounts 50,389 312,927 288,605 74,711 Allowance for uncompensated care 52,168 71,011 76,792 46,387 (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 Accoun26

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
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 North America and to a lesser extent in 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 and the Middle East. 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 earnings (loss) of unconsolidated affiliates. At December 31, 2015, Al A. Gonsoulin, Chairman of the Board and Chief Executive Officer, beneficially owned stock representing approximately 70.2% 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.
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, Inventories of spare parts, 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, Income taxes, Healthcare insurance claims and workers’ compensation liability, and Impairment of long-lived 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. Provisions for contractual discounts and uncompensated care that we applied to our Air Medical trade receivables (expressed as a percentage of total segment billings) at December 31 were as follows: 2015 2014 Allowance for contractual discounts 56 % 53 % Allowance for uncompensated care 23 % 23 %
Short-term Investments	Short-term Investments Short-term investments consist of money market funds, 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. The Company recorded less than $0.9 million in net unrealized losses in 2015. These losses are reflected as a separate component of stockholders’ equity.
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. Valuation reserves related to obsolescence and slow-moving inventory were $15.4 million and $13.5 million at December 31, 2015 and 2014, respectively.
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 five to fifteen years for flight equipment and three to ten 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 six to ten 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 (historical as of 2007). 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 asset. 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 assets for impairment annually, or more frequently if events or a change of circumstances indicate that an impairment may have occurred. The Company reviews certain identifiable intangibles for impairment whenever events or changes in circumstances indicate that the carrying amount of any such asset may not be recoverable. 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 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 form 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, 2015, we sold and disposed of eight light and six medium aircraft previously utilized in our Oil and Gas segment. The carrying value of these assets prior to the sale was $3.7 million. These assets were sold for $3.7 million, which resulted in no gain. These aircraft no longer met our strategic needs. We also sold the associated spare parts inventory for these aircraft, which resulted in a $0.3 million loss. During the twelve months ended December 31, 2014, we sold nine light and three fixed wing aircraft previously utilized in our Oil and Gas segment. The carrying value of these assets prior to the sale was $5.5 million. These assets were sold for $5.9 million, which resulted in a gain of $0.4 million. We also sold or disposed of one medium and four light aircraft previously utilized in our Air Medical segment. The carrying value of these assets prior to the sale was $10.8 million. These assets were sold for $8.2 million, resulting in a loss of $2.6 million. These aircraft no longer met our strategic needs. Sales and disposals of various ancillary equipment resulted in a gain of $1.4 million.
Impairment Losses	Impairment Losses In connection with our normal recurring impairment testing, we recorded an impairment loss in the year ended December 31, 2014 for 13 medium aircraft in our Oil and Gas segment and one medium aircraft in our Air Medical segment. The carrying value of these aircraft was $16.5 million. Following a market analysis, we determined that the market value for these aircraft was $6.0 million. Similarly, we also recorded an impairment loss in the year ended 2013 for two medium aircraft in our Oil and Gas segment and two medium aircraft in our Air Medical segment. The carrying value of these aircraft was $4.0 million. Following a market analysis, we determined that the market value of these aircraft was $2.4 million. As a result of these analyses, we recorded aggregate non-cash pre-tax impairment losses of $10.5 million and $1.6 million for 2014 and 2013, respectively. We did not record an impairment loss in the year ended December 31, 2015. See Note 3 for additional information.
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, 2015. As of December 31, 2015 and 2014, the Company had $1.9 million and $1.7 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 $2.6 million and $2.5 million for the years 2015 and 2014, 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 $1.0 million and $0.9 million, respectively, to this captive company in 2015 and 2014, which were eliminated in consolidation. The results of the captive are fully consolidated in the accompanying consolidated financial statements.
Revenue Recognition	Revenue Recognition The Company recognizes revenue related to aviation transportation services after the services are performed or the contractual obligations are met. Aircraft maintenance services revenues are recognized at the time the repair or services work is completed. Revenues related to the Company’s Air Medical segment independent provider model services are recorded net of contractual allowances under agreements with third party payors, and also recorded net of uncompensated care allowances when the services are provided. Revenues generated under the traditional provider model consist of a fixed monthly rate for aircraft availability and an hourly rate for flight time. 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. The allowance for contractual discounts against outstanding accounts receivable was $103.6 million, $96.6 million, and $74.7 million as of December 31, 2015, 2014, and 2013, respectively. The allowance for uncompensated care against outstanding accounts receivable was $41.9 million, $41.9 million, and $46.4 million as of December 31, 2015, 2014, and 2013, 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 $9.3 million, $9.1 million, and $7.9 million for the years ended December 31, 2015, 2014, and 2013, respectively. The estimated cost of providing charity services was $2.0 million, $2.1 million, and $3.0 million for the years ended December 31, 2015, 2014, and 2013, 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 segment’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 by each individual 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 nine 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 segment billings) were as follows: Year Ended December 31, 2015 2014 2013 Provision for contractual discounts 65 % 72 % 60 % Provision for uncompensated care 8 % 2 % 10 % Amounts attributable to Medicaid, Medicare, private insurance, and self-pay as a percentage of net Air Medical revenues were as follows: Year Ended December 31, 2015 2014 2013 Insurance 74 % 74 % 73 % Medicare 17 % 18 % 19 % Medicaid 8 % 8 % 7 % Self-Pay 1 % 0 % 1 % Under a three-year 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 has been extended to June 29, 2016 on terms that have reduced the number of aircraft operated by us and the scope of our services and responsibilities. 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
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. The Company does not believe significant credit risk existed with respect to these trade accounts receivable at December 31, 2015. 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 and U.S. governmental agencies. 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 in the Oil and Gas and Technical Services segments was $3.2 million and $0.1 million at December 31, 2015 and 2014, 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. The allowance for contractual discounts was $103.6 million, $96.6 million, and $74.7 million as of December 31, 2015, 2014, and 2013, respectively. The allowance for uncompensated care was $41.9 million, $41.9 million, and $46.4 million as of December 31, 2015, 2014, and 2013, respectively. The Company’s two largest oil and gas customers accounted for 26% of consolidated operating revenues for the year ended December 31, 2015, 30% for the year ended December 31, 2014, and 28% for the year ended December 31, 2013. The Company also carried accounts receivable from these same customers totaling 15% and 18% of net trade receivables on December 31, 2015 and 2014, respectively. The Company’s largest Air Medical customer accounted for 9% and 10% of consolidated operating revenues for the years ended December 31, 2015 and 2014, respectively. The Company also carried accounts receivable from this customer totaling 15% and 20% of net trade receivables on December 31, 2015 and 2014, 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.
New Accounting Pronouncements	New Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers In August 2014, the FASB issued ASU 2014-15 Presentation of Financial Statements – Going Concern (Subtopic 205-40): of Uncertainties about an Entity’s Ability to Continue as a Going Concern In April 2015, the FASB issued ASU No. 2015-03, Simplifying the Presentation of Debt Issuance Costs. In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes

Summary of Significant Accoun27

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Provisions for Contractual Discounts and Uncompensated Care Applied to Air Medical Trade Receivables Expressed as Percentage of Total Segment Billings	Provisions for contractual discounts and uncompensated care that we applied to our Air Medical trade receivables (expressed as a percentage of total segment billings) at December 31 were as follows: 2015 2014 Allowance for contractual discounts 56 % 53 % Allowance for uncompensated care 23 % 23 %
Schedule of Provisions for Contractual Discounts and Estimated Uncompensated Care Applied to Air Medical Revenues Expressed as Percentage of Total Segment Billings	Provisions for contractual discounts and estimated uncompensated care that we applied to our Air Medical revenues (expressed as a percentage of total segment billings) were as follows: Year Ended December 31, 2015 2014 2013 Provision for contractual discounts 65 % 72 % 60 % Provision for uncompensated care 8 % 2 % 10 %
Schedule of Net Revenue Attributable to Medicaid, Medicare, Private Insurance and Self Pay as Percentage of Net Air Medical Revenues	Amounts attributable to Medicaid, Medicare, private insurance, and self-pay as a percentage of net Air Medical revenues were as follows: Year Ended December 31, 2015 2014 2013 Insurance 74 % 74 % 73 % Medicare 17 % 18 % 19 % Medicaid 8 % 8 % 7 % Self-Pay 1 % 0 % 1 %

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Components of Investments	Investments consisted of the following as of December 31, 2015: Unrealized Unrealized Fair Cost Basis Gains Losses Value (Thousands of dollars) Investments: Money market mutual funds $ 18,181 $ — $ — $ 18,181 Commercial paper 5,986 — (5 ) 5,981 U.S. government agencies 11,499 — (30 ) 11,469 Corporate bonds and notes 265,069 — (841 ) 264,228 Subtotal 300,735 — (876 ) 299,859 Deferred compensation plan assets included in other assets 2,294 — — 2,294 Total $ 303,029 $ — $ (876 ) $ 302,153 Investments consisted of the following as of December 31, 2014: Unrealized Unrealized Fair Cost Basis Gains Losses Value (Thousands of dollars) Investments: Money market mutual funds $ 68,612 $ — $ — $ 68,612 Municipal bonds and notes 1,500 2 — 1,502 Corporate bonds and notes 130,864 19 (268 ) 130,615 Subtotal 200,976 21 (268 ) 200,729 Deferred compensation plan assets included in other assets 2,386 — — 2,386 Total $ 203,362 $ 21 $ (268 ) $ 203,115
Cost and Fair Value of Debt Investments Based on Maturities	The following table presents the cost and fair value of our debt investments based on maturities as of December 31, 2015 2014 Amortized Fair Amortized Fair Costs Value Costs Value (Thousands of dollars) Due in one year or less $ 152,444 $ 152,212 $ 70,180 $ 70,169 Due within two years 130,110 129,466 62,184 61,948 Total $ 282,554 $ 281,678 $ 132,364 $ 132,117
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, 2015 2014 Average Average Average Average Coupon Days To Coupon Days To Rate (%) Maturity Rate (%) Maturity Commercial paper 0.553 154 n/a n/a U.S. government agencies 0.865 599 n/a n/a Municipal bonds and notes n/a n/a 0.528 134 Corporate bonds and notes 1.757 331 1.828 348
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, 2015 2014 Unrealized Unrealized Fair Value Losses Fair Value Losses (Thousands of dollars) Commercial paper $ 5,981 $ (5 ) $ — $ — U.S. government agencies 8,969 (30 ) — — Corporate bonds and notes 232,347 (793 ) 100,071 (268 ) Total $ 247,297 $ (828 ) $ 100,071 $ (268 )
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, 2015 2014 Unrealized Unrealized Fair Value Losses Fair Value Losses (Thousands of dollars) Corporate bonds and notes $ 28,866 $ (48 ) $ — $ — Total $ 28,866 $ (48 ) $ — $ —

Fair Value (Tables)

Fair Value (Tables)	12 Months Ended
	Dec. 31, 2015
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, 2015 Total (Level 1) (Level 2) Investments: Money Market Mutual Funds $ 18,181 $ 18,181 $ — Commercial Paper 5,981 — 5,981 U.S. Government Agencies 11,469 — 11,469 Corporate bonds and notes 264,228 — 264,228 299,859 18,181 281,678 Deferred compensation plan assets 2,294 2,294 — Total $ 302,153 $ 20,475 $ 281,678 December 31, 2014 Total (Level 1) (Level 2) Investments: Money Market Mutual Funds $ 68,612 $ 68,612 $ — Municipal bonds and notes 1,502 — 1,502 Corporate bonds and notes 130,615 — 130,615 200,729 68,612 132,117 Deferred compensation plan assets 2,386 2,386 — Total $ 203,115 $ 70,998 $ 132,117
Summary of Combined Fair Value of Assets that Incurred Impairments	The below table summarizes the combined fair value of the assets that incurred impairments during the years ended December 31, 2015 and 2014, along with the amount of the impairment. The impairment charges were recorded in Impairment of assets. Year Ended December 31, 2015 2014 (Thousands of dollars) Amount of impairment incurred $ — $ 10,508 Combined fair value of assets incurring impairment $ — $ 6,000

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2015
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: 2015 2014 (Thousands of dollars) Flight equipment $ 1,096,986 $ 1,053,640 Facility & improvements 61,330 61,246 Operating equipment 26,004 24,764 Data processing equipment 33,178 32,374 Vehicles 8,461 8,133 Medical equipment 7,514 7,377 Other 5,377 5,332 1,238,850 1,192,866 Less accumulated depreciation and amortization (355,321 ) (315,048 ) Property and equipment, net $ 883,529 $ 877,818

Other Assets (Tables)

Other Assets (Tables)	12 Months Ended
	Dec. 31, 2015
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: 2015 2014 (Thousands of dollars) Deposits on future purchases of aircraft $ 3,568 $ 8,305 Deferred financing cost 3,999 5,246 Investments (Officers’ Deferred Compensation Plan) 2,294 2,386 Other 316 316 Total $ 10,177 $ 16,253

Accrued and Other Current Lia32

Accrued and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued and other current liabilities as of December 31 consisted of the following: 2015 2014 (Thousands of dollars) Salaries & wages $ 19,955 $ 16,203 Incentive compensation 2,819 11,730 Income taxes 1,453 3,787 Interest 7,925 7,891 Vacation payable 5,801 6,112 Group medical 1,944 1,735 Transportations tax 892 907 Operating lease 814 1,227 Workers compensation 1,047 1,185 Other 2,109 2,035 Total accrued liabilities $ 44,759 $ 52,812

Long Term Debt (Tables)

Long Term Debt (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Components of Long-term Debt	The components of long-term debt as of December 31 are as follows: 2015 2014 (Thousands of dollars) Senior Notes issued March 17, 2014, interest only payable semi-annually at 5.25%, maturing March 15, 2019 $ 500,000 $ 500,000 Revolving Credit Facility due October 1, 2017 with a group of commercial banks, interest payable at variable rates 57,500 43,000 Total long-term debt $ 557,500 $ 543,000
Summary of Annual Maturities of Long-term Debt	Listed below is information on our future annual maturities of long-term debt (in thousands): 2016 $ — 2017 57,500 2018 — 2019 500,000 2020 — Thereafter — Total $ 557,500

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Schedule of Income Tax Expense	Income tax expense is composed of the following: Year Ended December 31, 2015 2014 2013 (Thousands of dollars) Current Federal $ — $ — $ — State 284 307 353 Foreign 3,159 4,352 9,637 Deferred – principally Federal 12,889 15,768 21,195 Total $ 16,332 $ 20,427 $ 31,185
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 35% as a result of the following: Year Ended Year Ended Year Ended December 31, December 31, December 31, (Thousands of dollars, except percentage amounts) Amount Tax Amount Tax Amount Tax Income taxes at statutory rate $ 15,140 35 $ 18,590 35 $ 31,550 35 Increase (decrease) in taxes resulting from: Valuation allowance on foreign tax credits — — 113 — — — Valuation allowance reversal–investment in foreign entity (456 ) (1 ) — — — — Change in tax rate on deferred items 1,078 3 — — (3,850 ) (4 ) State income taxes, net of federal benefit 146 — 916 2 2,161 2 Other items – net 424 1 808 1 1,324 2 Total $ 16,332 38 $ 20,427 38 $ 31,185 35
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: 2015 2014 (Thousands of dollars) Deferred tax assets: Deferred compensation $ 946 $ 1,023 Foreign tax credits 20,118 16,982 Vacation and bonus accrual 1,952 2,031 Inventory valuation 6,808 6,093 Rental accrual 1,691 1,799 Hurricane relief credit 1,255 1,255 Stock-based compensation 3,598 2,977 Other 3,593 2,714 Net operating losses 61,611 56,305 Total deferred tax assets 101,572 91,179 Valuation allowance – state NOL carryforwards (290 ) (219 ) Valuation allowance – tax credit carryforwards (2,047 ) (2,047 ) Valuation allowance – other — (1,466 ) Total deferred tax assets, net 99,235 87,447 Deferred tax liabilities: Tax depreciation in excess of book depreciation (242,501 ) (218,064 ) Total deferred tax liabilities (242,501 ) (218,064 ) Net deferred tax liabilities $ (143,266 ) $ (130,617 ) Current deferred tax assets $ 10,379 $ 9,915 Deferred tax liability – long-term (153,645 ) (140,532 ) Net deferred tax liabilities $ (143,266 ) $ (130,617 )

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2015
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: 2015 2014 2013 (in thousands) Weighted average outstanding shares of common stock, basic 15,566 15,483 15,474 Dilutive effect of restricted stock units 76 202 165 Weighted average outstanding shares of common stock, diluted 15,642 15,685 15,639

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2015
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, 2015. Share Units Weighted Grant-Date Remaining Aggregate Value Outstanding at January 1, 2015 4,488 $ 41.19 2.48 $ 185 Granted 4,317 21.42 Forfeited — — Vested and released to participants — — Outstanding at December 31, 2015 8,805 $ 31.50 2.21 $ 277
Non-Voting Time-Vested Restricted Stock Units [Member]
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, 2015. Share Units Weighted Grant-Date Remaining (in years) Aggregate Value (in thousands) Outstanding at January 1, 2015 191,655 $ 38.56 2.26 $ 7,391 Granted 35,456 30.17 Forfeited (8,026 ) (22.81 ) Vested and released to participants (37,610 ) (24.82 ) Outstanding at December 31, 2015 181,475 $ 40.47 1.56 $ 7,344
Non-Voting Performance Based Restricted Stock Units [Member]
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, 2015. Share Units Weighted Grant-Date Remaining (in years) Aggregate Value (in thousands) Outstanding at January 1, 2015 394,669 $ 30.07 1.78 $ 11,878 Granted 152,331 33.41 Forfeited (10,758 ) (22.81 ) Vested and released to participants (141,286 ) (23.04 ) Outstanding at December 31, 2015 394,956 $ 34.07 1.83 $ 13,456

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
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 December 31, December 31, December 31, 2015 2014 2013 (Thousands of dollars) Aircraft $ 45,360 $ 44,908 $ 41,803 Other 8,358 7,790 7,657 Total $ 53,718 $ 52,698 $ 49,460
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) 2016 $ 44,988 $ 5,305 $ 50,293 2017 42,699 3,193 45,892 2018 39,018 2,552 41,570 2019 32,365 1,983 34,348 2020 28,526 1,413 29,939 Thereafter 89,604 745 90,349 $ 277,200 $ 15,191 $ 292,391

Business Segments and Geograp38

Business Segments and Geographic Areas (Tables)	12 Months Ended
	Dec. 31, 2015
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 Operating Revenues December 31, Years Ended December 31, 2015 2014 2015 2014 2013 Oil and Gas segment: Customer A 6 % 7 % 15 % 17 % 15 % Customer B 9 % 12 % 11 % 13 % 13 % Air Medical & Technical Services segments: Customer C 15 % 20 % 9 % 10 % 17 %
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, 2015, 2014, and 2013. Year Ended December 31, 2015 2014 2013 (Thousands of dollars) Segment operating revenues Oil and Gas $ 459,611 $ 516,909 $ 489,055 Air Medical 312,775 300,212 277,884 Technical Services 31,842 19,149 89,561 Total operating revenues 804,228 836,270 856,500 Segment direct expenses Oil and Gas (1) 411,757 411,679 393,251 Air Medical 246,487 243,573 231,880 Technical Services 29,112 14,851 88,221 Total segment direct expenses 687,356 670,103 713,352 Segment selling, general and administrative expenses Oil and Gas 6,511 4,615 4,059 Air Medical (2) 10,455 9,801 8,875 Technical Services 805 157 1 Total segment selling, general and administrative expenses 17,771 14,573 12,935 Total segment expenses 705,127 684,676 726,287 Net segment profit Oil and Gas 41,343 100,615 91,745 Air Medical 55,833 46,838 37,129 Technical Services 1,925 4,141 1,339 Total 99,101 151,594 130,213 Other, net (3) 1,872 (10,539 ) 15,569 Unallocated selling, general and administrative expenses (28,651 ) (28,597 ) (26,207 ) Interest expense (29,066 ) (29,510 ) (29,434 ) Loss on debt extinguishment — (29,833 ) — Earnings before income taxes $ 43,256 $ 53,115 $ 90,141 (1) Includes equity in loss of unconsolidated affiliate. (2) Includes interest expense $0.3 million for the year ended December 31, 2013. (3) Includes gains 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, 2015 2014 2013 (Thousands of dollars) Expenditures for long-lived assets Oil and Gas $ 32,501 $ 119,235 $ 62,934 Air Medical 22,685 37,317 37,728 Corporate 1,389 1,153 1,928 Total $ 56,575 $ 157,705 $ 102,590 Year Ended December 31, 2015 2014 2013 (Thousands of dollars) Depreciation and Amortization Oil and Gas $ 42,709 $ 29,635 $ 26,653 Air Medical 18,177 13,067 11,395 Technical Services 518 493 172 Corporate 10,214 7,653 4,628 Total $ 71,618 $ 50,848 $ 42,848 Assets Oil and Gas $ 704,472 $ 726,008 Air Medical 329,484 336,510 Technical Services 7,345 7,842 Corporate 389,031 305,720 Total $ 1,430,332 $ 1,376,080
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, 2015 2014 2013 (Thousands of dollars) Operating revenues: United States $ 722,339 $ 747,063 $ 699,298 International 81,889 89,207 157,202 Total $ 804,228 $ 836,270 $ 856,500 Long-Lived Assets: United States $ 773,939 $ 846,377 International 109,590 31,441 Total $ 883,529 $ 877,818

Quarterly Financial Data (Una39

Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Summary of Condensed Quarterly Results of Operations	The condensed quarterly results of operations for the years ended December 31, 2015 and 2014 (in thousands of dollars, except per share data) were as follows: Quarter Ended March 31, June 30, September 30, December 31, 2015 2015 2015 2015 (Thousands of dollars, except per share data) Operating revenues $ 204,197 $ 198,547 $ 214,733 $ 186,751 Gain (loss) on disposition of assets, net 7 66 165 (577 ) Earnings (loss) before income taxes 16,984 11,044 14,290 938 Net earnings 10,363 6,454 7,669 2,438 Net earnings per share Basic 0.67 0.41 0.49 0.16 Diluted 0.66 0.41 0.49 0.16 Quarter Ended March 31, June 30, September 30, December 31, 2014 2014 2014 2014 (Thousands of dollars, except per share data) Operating revenues, net $ 197,071 $ 212,145 $ 216,294 $ 210,760 Gain (loss) on disposition of assets, net (1,073 ) (242 ) (56 ) 523 Earnings (loss) before income taxes (8,513 ) 21,700 28,277 11,651 Net earnings (loss) (5,321 ) 13,368 17,249 7,392 Net earnings (loss) per share Basic (0.34 ) 0.86 1.11 0.48 Diluted (0.34 ) 0.85 1.10 0.47

Condensed Consolidating Finan40

Condensed Consolidating Financial Information - Guarantor Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2015
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, 2015 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated ASSETS Current Assets: Cash $ 46 $ 2,361 $ — $ 2,407 Short-term investments 284,523 — — 284,523 Accounts receivable – net 70,336 74,442 — 144,778 Intercompany receivable — 90,943 (90,943 ) — Inventories of spare parts – net 60,060 9,431 — 69,491 Prepaid expenses 7,162 1,789 — 8,951 Deferred income taxes 10,379 — — 10,379 Income taxes receivable 1,002 (241 ) — 761 Total current assets 433,508 178,725 (90,943 ) 521,290 Investment in subsidiaries 330,848 — (330,848 ) — Property and equipment, net 632,759 250,770 — 883,529 Restricted investments 15,336 — — 15,336 Other assets 9,974 203 — 10,177 Total assets $ 1,422,425 $ 429,698 $ (421,791 ) $ 1,430,332 LIABILITIES AND SHAREHOLDERS’ EQUITY Current Liabilities: Accounts payable $ 25,512 $ 5,861 $ — $ 31,373 Accrued liabilities 29,138 15,621 — 44,759 Intercompany payable 90,943 — (90,943 ) — Total current liabilities 145,593 21,482 (90,943 ) 76,132 Long-term debt 557,500 — — 557,500 Deferred income taxes and other long-term liabilities 92,334 77,368 — 169,702 Shareholders’ Equity: Common stock and paid-in capital 306,444 79,061 (79,061 ) 306,444 Accumulated other comprehensive loss (567 ) — — (567 ) Retained earnings 321,121 251,787 (251,787 ) 321,121 Total shareholders’ equity 626,998 330,848 (330,848 ) 626,998 Total liabilities and shareholders’ equity $ 1,422,425 $ 429,698 $ (421,791 ) $ 1,430,332 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. December 31, 2014 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated ASSETS Current Assets: Cash $ 51 $ 6,219 $ — $ 6,270 Short-term investments 185,244 — — 185,244 Accounts receivable – net 98,001 82,760 — 180,761 Intercompany receivable — 95,399 (95,399 ) — Inventories of spare parts – net 65,341 8,452 — 73,793 Prepaid expenses 7,610 1,704 — 9,314 Deferred income taxes 9,915 — — 9,915 Income taxes receivable 1,068 159 — 1,227 Total current assets 367,230 194,693 (95,399 ) 466,524 Investment in subsidiaries and others 358,080 — (358,080 ) — Property and equipment, net 638,437 239,381 — 877,818 Restricted investments 15,485 — — 15,485 Other assets 16,055 198 — 16,253 Total assets $ 1,395,287 $ 434,272 $ (453,479 ) $ 1,376,080 LIABILITIES AND SHAREHOLDERS’ EQUITY Current Liabilities: Accounts payable $ 22,578 $ 5,122 $ — $ 27,700 Accrued and other current liabilities 34,477 18,335 — 52,812 Intercompany payable 95,270 — (95,270 ) — Total current liabilities 152,325 23,457 (95,270 ) 80,512 Long-term debt 543,000 — — 543,000 Deferred income taxes and other long-term liabilities 102,894 52,606 — 155,500 Shareholders’ Equity: Common stock and paid-in capital 303,082 137,647 (137,647 ) 303,082 Accumulated other comprehensive loss (211 ) — — (211 ) Retained earnings 294,197 220,562 (220,562 ) 294,197 Total shareholders’ equity 597,068 358,209 (358,209 ) 597,068 Total liabilities and shareholders’ equity $ 1,395,287 $ 434,272 $ (453,479 ) $ 1,376,080 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts.
Condensed Consolidating Statements of Operations	PHI, INC. AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS (Thousands of dollars) For the year ended December 31, 2015 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated Operating revenues, net $ 476,969 $ 327,259 $ — $ 804,228 Expenses: Direct expenses 426,239 260,829 (18 ) 687,050 Selling, general, and administrative expenses 35,694 10,728 — 46,422 Total operating expenses 461,933 271,557 (18 ) 733,472 Loss on disposition of assets, net 339 — — 339 Equity in loss of unconsolidated affiliate 306 — — 306 Operating income 14,391 55,702 18 70,111 Equity in net earnings of consolidated subsidiaries (31,225 ) — 31,225 — Interest expense 28,946 120 — 29,066 Other income, net (2,222 ) (7 ) 18 (2,211 ) (4,501 ) 113 31,243 26,855 Earnings before income taxes 18,992 55,589 (31,225 ) 43,256 Income tax expense (8,032 ) 24,364 — 16,332 Net earnings $ 26,924 $ 31,225 $ (31,225 ) $ 26,924 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. For the year ended December 31, 2014 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated Operating revenues, net $ 504,180 $ 332,090 $ — $ 836,270 Expenses: Direct expenses 411,398 258,627 (18 ) 670,007 Selling, general, and administrative expenses 32,985 10,186 — 43,171 Total operating expenses 444,383 268,813 (18 ) 713,178 Loss on disposition of assets, net 848 — — 848 Impairment of assets 10,508 — — 10,508 Equity in loss of unconsolidated affiliate 96 — — 96 Operating income 48,345 63,277 18 111,640 Equity in net earnings of consolidated subsidiaries (38,740 ) — 38,740 — Interest expense 29,510 — — 29,510 Loss on debt extinguishment 29,833 — — 29,833 Other (income) expense, net (819 ) (17 ) 18 (818 ) 19,784 (17 ) 38,758 58,525 Earnings before income taxes 28,561 63,294 (38,740 ) 53,115 Income tax (benefit) expense (4,127 ) 24,554 — 20,427 Net earnings $ 32,688 $ 38,740 $ (38,740 ) $ 32,688 For the year ended December 31, 2013 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated Operating revenues, net $ 564,445 $ 292,055 $ — $ 856,500 Expenses: Direct expenses 468,321 244,769 — 713,090 Selling, general, and administrative expenses 29,885 8,935 — 38,820 Management fees (11,682 ) 11,682 — — Total operating expenses 486,524 265,386 — 751,910 (Gain) on disposition of assets, net (16,585 ) (19 ) — (16,604 ) Impairment of assets 1,227 421 — 1,648 Equity in loss of unconsolidated affiliate 262 — — 262 Operating income 93,017 26,267 — 119,284 Equity in net earnings of consolidated subsidiaries (15,567 ) — 15,567 — Interest expense 29,434 322 — 29,756 Other income, net (613 ) — — (613 ) 13,254 322 15,567 29,143 Earnings before income taxes 79,763 25,945 (15,567 ) 90,141 Income tax expense 20,807 10,378 — 31,185 Net earnings $ 58,956 $ 15,567 $ (15,567 ) $ 58,956 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts.
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, 2015 Parent Company Guarantor Only Subsidiaries (1) Eliminations Consolidated Net earnings $ 26,924 $ 31,225 $ (31,225 ) $ 26,924 Unrealized gain (loss) on short-term investments (641 ) — — (641 ) Other unrealized gain (loss) 24 — — 24 Changes in pension plan assets and benefit obligations 7 — — 7 Tax impact 254 — — 254 $ 26,568 $ 31,225 $ (31,225 ) $ 26,568 For the year ended December 31, 2014 Parent Company Guarantor Only Subsidiaries (1) Eliminations Consolidated Net earnings $ 32,688 $ 38,740 $ (38,740 ) $ 32,688 Unrealized gain (loss) on short-term investments (285 ) — — (285 ) Other unrealized gain (loss) (24 ) — — (24 ) Changes in pension plan assets and benefit obligations 17 — — 17 Tax impact 105 — — 105 $ 32,501 $ 38,740 $ (38,740 ) $ 32,501 For the year ended December 31, 2013 Parent Company Guarantor Only Subsidiaries (1) Eliminations Consolidated Net earnings $ 58,956 $ 15,567 $ (15,567 ) $ 58,956 Unrealized gain (loss) on short-term investments 44 — — 44 Changes in pension plan assets and benefit obligations (2 ) — — (2 ) Tax impact (15 ) — — (15 ) $ 58,983 $ 15,567 $ (15,567 ) $ 58,983 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts.
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, 2015 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated Net cash provided by operating activities $ 60,241 $ 73,677 $ — $ 133,918 Investing activities: Purchase of property and equipment (57,123 ) — — (57,123 ) Proceeds from asset dispositions 5,236 — — 5,236 Purchase of short-term investments (608,649 ) — — (608,649 ) Proceeds from sale of short-term investments 505,966 — — 505,966 Payments of deposits on aircraft (1,273 ) — — (1,273 ) Refunds on deposits on aircraft 6,010 — — 6,010 Net cash used in investing activities (149,833 ) — — (149,833 ) Financing activities: Repurchase of common stock (2,448 ) (2,448 ) Proceeds on line of credit 232,660 — — 232,660 Payments on line of credit (218,160 ) — — (218,160 ) Due to/from affiliate, net 77,535 (77,535 ) — — Net cash provided by financing activities 89,587 (77,535 ) — 12,052 Decrease in cash (5 ) (3,858 ) — (3,863 ) Cash, beginning of year 51 6,219 — 6,270 Cash, end of year $ 46 $ 2,361 $ — $ 2,407 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. For the year ended December 31, 2014 Parent Company Guarantor Only (issuer) Subsidiaries (1) Eliminations Consolidated Net cash provided by operating activities $ 51,476 $ 68,043 $ — $ 119,519 Investing activities: Purchase of property and equipment (157,690 ) — — (157,690 ) Proceeds from asset dispositions 10,266 — — 10,266 Purchase of short-term investments (465,094 ) — — (465,094 ) Proceeds from sale of short-term investments 363,110 — — 363,110 Refund of deposits on aircraft 11,506 — — 11,506 Payments of deposits on aircraft (6,948 ) — — (6,948 ) Loan to unconsolidated affiliate (200 ) — — (200 ) Net cash used in investing activities (245,050 ) — — (245,050 ) Financing activities: Proceeds from issuance of Senior Notes due 2019 500,000 — — 500,000 Repayment of Senior Notes due 2018 (300,000 ) — — (300,000 ) Premium and cost to retire debt early (26,749 ) — — (26,749 ) Debt issuance costs (6,232 ) — — (6,232 ) Proceeds from line of credit 264,253 — — 264,253 Payments on line of credit (300,253 ) — — (300,253 ) Repurchase of common stock (152 ) — — (152 ) Due to/from affiliate, net 62,706 (62,706 ) — — Net cash provided by financing activities 193,573 (62,706 ) — 130,867 (Decrease) increase in cash (1 ) 5,337 — 5,336 Cash, beginning of year 52 882 — 934 Cash, end of year $ 51 $ 6,219 $ — $ 6,270 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. For the year ended December 31, 2013 Parent Company Guarantor Only (issuer) Subsidiaries (1) (2) Eliminations Consolidated Net cash provided by operating activities $ 82,660 $ 22,436 $ — $ 105,096 Investing activities: Purchase of property and equipment (102,726 ) — — (102,726 ) Proceeds from asset dispositions 42,197 — — 42,197 Purchase of short-term investments (375,503 ) — — (375,503 ) Proceeds from sale of short-term investments 338,970 — — 338,970 Payments of deposits on aircraft (9,318 ) — — (9,318 ) Refunds on deposits on aircraft 8,161 — — 8,161 Net cash used in investing activities (98,219 ) — — (98,219 ) Financing activities: Repurchase of common stock (1,037 ) (1,037 ) Proceeds on line of credit 164,771 — — 164,771 Payments on line of credit (172,526 ) — — (172,526 ) Due to/from affiliate, net 23,851 (23,851 ) — — Net cash provided by financing activities 15,059 (23,851 ) — (8,792 ) Decrease in cash (500 ) (1,415 ) — (1,915 ) Cash, beginning of year 552 2,297 — 2,849 Cash, end of year $ 52 $ 882 $ — $ 934 (1) Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries’ amounts. (2) Cash flows between the Parent Company and guarantor subsidiaries related to the Company’s centralized cash management activities in 2013 have been adjusted to show the effects on net cash provided by operating and financing activities.

Summary of Significant Accoun41

Summary of Significant Accounting Policies - Additional Information (Detail)	Sep. 29, 2012	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Sep. 30, 2014USD ($)	Jun. 30, 2014USD ($)	Mar. 31, 2014USD ($)	Dec. 31, 2015USD ($)Aircraft	Dec. 31, 2014USD ($)Aircraft	Dec. 31, 2013USD ($)Aircraft
Summary Of Significant Accounting Policies [Line Items]
Percentage of stock owned by CEO										70.20%
Maturities Period of liquid investments										Three months or less
Valuation reserves related to obsolescence and slow moving inventory		$ 15,400,000				$ 13,500,000				$ 15,400,000	$ 13,500,000
Gain or loss on sale of assets		(577,000)	$ 165,000	$ 66,000	$ 7,000	523,000	$ (56,000)	$ (242,000)	$ (1,073,000)	(339,000)	(848,000)	$ 16,604,000
Impairments of assets											10,508,000	1,648,000
Insurance retention per claim										250,000
Accrued liabilities related to health care claims		1,900,000				1,700,000				1,900,000	1,700,000
Amount deductible per incident										500,000
Accrued expense related to workers compensation claims		2,600,000				2,500,000				2,600,000	2,500,000
Amounts paid to offshore insurance captive										1,000,000	900,000
Allowance for contractual discounts against outstanding accounts receivable		103,600,000				96,600,000				103,600,000	96,600,000	74,700,000
Allowance for uncompensated care against outstanding accounts receivable		41,900,000				41,900,000				41,900,000	41,900,000	46,400,000
Value of uncompensated care services		9,300,000				9,100,000				9,300,000	9,100,000	7,900,000
Estimated cost of providing charity services		$ 2,000,000				$ 2,100,000				$ 2,000,000	$ 2,100,000	$ 3,000,000
Percentage of reserved category of self pay										100.00%
Percentage of consolidated operating revenues										26.00%	30.00%	28.00%
Percentage of trade receivables		15.00%				18.00%				15.00%	18.00%
Debt issuance cost										$ 4,000,000	$ 5,200,000
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Unrealized losses recorded										(900,000)
Medium Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Carrying value of aircraft						$ 16,500,000					16,500,000	$ 4,000,000
Market value of aircraft						6,000,000					6,000,000	2,400,000
Impairments of assets										0	10,500,000	$ 1,600,000
Oil and Gas [Member]
Summary Of Significant Accounting Policies [Line Items]
Carrying value of aircraft		$ 3,700,000				5,500,000				3,700,000	5,500,000
Cash realized from sale of assets										3,700,000	5,900,000
Gain or loss on sale of assets										$ 0	$ 400,000
Oil and Gas [Member] | Light Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of aircraft sold | Aircraft										8	9
Oil and Gas [Member] | Medium Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of aircraft sold | Aircraft										6
Number of Aircraft impaired | Aircraft											13	2
Oil and Gas [Member] | Fixed Wing Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of aircraft sold | Aircraft											3
Air Medical [Member]
Summary Of Significant Accounting Policies [Line Items]
Carrying value of aircraft						10,800,000					$ 10,800,000
Cash realized from sale of assets											8,200,000
Gain or loss on sale of assets											(2,600,000)
Allowance for contractual discounts against outstanding accounts receivable		103,600,000				96,600,000				$ 103,600,000	96,600,000	$ 74,700,000
Allowance for uncompensated care against outstanding accounts receivable		41,900,000				41,900,000				41,900,000	$ 41,900,000	$ 46,400,000
Term of contract for providing products and services to a customer in Middle East	3 years
Air Medical [Member] | Light Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of aircraft sold | Aircraft											4
Air Medical [Member] | Medium Aircraft [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of aircraft sold | Aircraft											1
Number of Aircraft impaired | Aircraft											1	2
Oil and Gas and Technical Services segments [Member]
Summary Of Significant Accounting Policies [Line Items]
Allowance for doubtful accounts		$ 3,200,000				$ 100,000				$ 3,200,000	$ 100,000
Air Medical and Technical Services [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of consolidated operating revenues										9.00%	10.00%
Percentage of trade receivables		15.00%				20.00%				15.00%	20.00%
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]
Summary Of Significant Accounting Policies [Line Items]
Gain or loss on sale of assets											$ 1,400,000
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
Spare Parts Inventory [Member]
Summary Of Significant Accounting Policies [Line Items]
Gain or loss on sale of assets										$ (300,000)

Summary of Significant Accoun42

Summary of Significant Accounting Policies - Provisions for Contractual Discounts and Uncompensated Care Applied to Air Medical Trade Receivables Expressed as Percentage of Total Segment Billings (Detail) - Air Medical [Member]	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Provisions For Contractual Discounts And Estimated Uncompensated Care [Line Items]
Allowance for contractual discounts	65.00%	72.00%	60.00%
Trade Accounts Receivable [Member]
Provisions For Contractual Discounts And Estimated Uncompensated Care [Line Items]
Allowance for contractual discounts	56.00%	53.00%
Allowance for uncompensated care	23.00%	23.00%

Summary of Significant Accoun43

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 Segment Billings (Detail) - Air Medical [Member]	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Provisions For Contractual Discounts And Estimated Uncompensated Care [Line Items]
Provision for contractual discounts	65.00%	72.00%	60.00%
Provision for uncompensated care	8.00%	2.00%	10.00%

Summary of Significant Accoun44

Summary of Significant Accounting Policies - Schedule of Net Revenue Attributable to Medicaid, Medicare, Private Insurance and Self Pay as Percentage of Net Air Medical Revenues (Detail) - Air Medical [Member]	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Insurance [Member]
Segment Reporting Information [Line Items]
Percentage of net Air Medical revenues	74.00%	74.00%	73.00%
Medicare [Member]
Segment Reporting Information [Line Items]
Percentage of net Air Medical revenues	17.00%	18.00%	19.00%
Medicaid [Member]
Segment Reporting Information [Line Items]
Percentage of net Air Medical revenues	8.00%	8.00%	7.00%
Self Pay [Member]
Segment Reporting Information [Line Items]
Percentage of net Air Medical revenues	1.00%	0.00%	1.00%

Investments - Additional Inform

Investments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Investments, Debt and Equity Securities [Abstract]
Proceeds from sales of short term investments	$ 505,966	$ 363,110	$ 338,970
Restricted investments	$ 15,336	$ 15,485

Investments - Components of Inv

Investments - Components of Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	$ 303,029	$ 203,362
Unrealized Gains		21
Unrealized Losses	(876)	(268)
Fair Value	302,153	203,115
Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	300,735	200,976
Unrealized Gains		21
Unrealized Losses	(876)	(268)
Fair Value	299,859	200,729
Investments [Member] | Money Market Mutual Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	18,181	68,612
Fair Value	18,181	68,612
Investments [Member] | Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	5,986
Unrealized Losses	(5)
Fair Value	5,981
Investments [Member] | US Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	11,499
Unrealized Losses	(30)
Fair Value	11,469
Investments [Member] | Municipal Bonds and Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis		1,500
Unrealized Gains		2
Fair Value		1,502
Investments [Member] | Corporate Bonds and Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	265,069	130,864
Unrealized Gains		19
Unrealized Losses	(841)	(268)
Fair Value	264,228	130,615
Deferred Compensation Plan Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	2,294	2,386
Fair Value	$ 2,294	$ 2,386

Investments - Cost and Fair Val

Investments - Cost and Fair Value of Debt Investments Based on Maturities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Available-for-sale Securities, Debt Maturities [Abstract]
Due in one year or less, Amortized Costs	$ 152,444	$ 70,180
Due within two years, Amortized Costs	130,110	62,184
Total, Amortized Costs	282,554	132,364
Due in one year or less, Fair Value	152,212	70,169
Due within two years, Fair Value	129,466	61,948
Total, Fair Value	$ 281,678	$ 132,117

Investments - Average Coupon Ra

Investments - Average Coupon Rate Percentage and the Average Days to Maturity of Debt (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Average Coupon Rate	0.553%
Average Days To Maturity	154 days
US Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Average Coupon Rate	0.865%
Average Days To Maturity	599 days
Municipal Bonds and Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Average Coupon Rate		0.528%
Average Days To Maturity		134 days
Corporate Bonds and Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Average Coupon Rate	1.757%	1.828%
Average Days To Maturity	331 days	348 days

Investments - Investments in Co

Investments - Investments in Continuous Unrealized Loss Position for Less Than Twelve Months (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Fair Value	$ 247,297	$ 100,071
Unrealized Losses	(828)	(268)
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	5,981
Unrealized Losses	(5)
US Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	8,969
Unrealized Losses	(30)
Corporate Bonds and Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	232,347	100,071
Unrealized Losses	$ (793)	$ (268)

Investments - Investments in 50

Investments - Investments in Continuous Unrealized Loss Position For Twelve Months Or More (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)
Schedule of Available-for-sale Securities [Line Items]
Fair Value	$ 28,866
Unrealized Losses	48
Corporate Bonds and Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value	28,866
Unrealized Losses	$ 48

Fair Value - Summary of Valuati

Fair Value - Summary of Valuation of Investments and Financial Instruments Pricing Levels (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	$ 302,153	$ 203,115
Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	299,859	200,729
Investments [Member] | Money Market Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	18,181	68,612
Investments [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	5,981
Investments [Member] | US Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	11,469
Investments [Member] | Corporate Bonds and Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	264,228	130,615
Investments [Member] | Municipal Bonds and Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total		1,502
Deferred Compensation Plan Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	2,294	2,386
(Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	20,475	70,998
(Level 1) [Member] | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	18,181	68,612
(Level 1) [Member] | Investments [Member] | Money Market Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	18,181	68,612
(Level 1) [Member] | Deferred Compensation Plan Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	2,294	2,386
(Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	281,678	132,117
(Level 2) [Member] | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	281,678	132,117
(Level 2) [Member] | Investments [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	5,981
(Level 2) [Member] | Investments [Member] | US Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	11,469
(Level 2) [Member] | Investments [Member] | Corporate Bonds and Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total	$ 264,228	130,615
(Level 2) [Member] | Investments [Member] | Municipal Bonds and Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total		$ 1,502

Fair Value - Summary of Combine

Fair Value - Summary of Combined Fair Value of Assets that Incurred Impairments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Fair Value Disclosures [Abstract]
Amount of impairment incurred	$ 10,508	$ 1,648
Combined fair value of assets incurring impairment	$ 6,000

Property and Equipment - Summar

Property and Equipment - Summary of Company's Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,238,850	$ 1,192,866
Less accumulated depreciation and amortization	(355,321)	(315,048)
Property and equipment, net	883,529	877,818
Flight Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,096,986	1,053,640
Facility & Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	61,330	61,246
Operating Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	26,004	24,764
Data Processing Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	33,178	32,374
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	8,461	8,133
Medical Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	7,514	7,377
Other [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 5,377	$ 5,332

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Abstract]
Depreciation expense related to property and equipment	$ 46.7	$ 43.7	$ 38.9

Other Assets - Schedule of Comp

Other Assets - Schedule of Company's Other Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deposits on future purchases of aircraft	$ 3,568	$ 8,305
Deferred financing cost	3,999	5,246
Investments (Officers' Deferred Compensation Plan)	2,294	2,386
Other	316	316
Total	$ 10,177	$ 16,253

Accrued and Other Current Lia56

Accrued and Other Current Liabilities - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Salaries & wages	$ 19,955	$ 16,203
Incentive compensation	2,819	11,730
Income taxes	1,453	3,787
Interest	7,925	7,891
Vacation payable	5,801	6,112
Group medical	1,944	1,735
Transportations tax	892	907
Operating lease	814	1,227
Workers compensation	1,047	1,185
Other	2,109	2,035
Total accrued liabilities	$ 44,759	$ 52,812

Long Term Debt - Components of

Long Term Debt - Components of Long-term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term debt	$ 557,500	$ 543,000
5.25% Senior Notes due March 15, 2019 [Member]
Debt Instrument [Line Items]
Long-term debt	500,000	500,000
5.25% Senior Notes due March 15, 2019 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	500,000	500,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt	$ 57,500	$ 43,000

Long Term Debt - Components o58

Long Term Debt - Components of Long-term Debt (Parenthetical) (Detail) - 5.25% Senior Notes due March 15, 2019 [Member] - Senior Notes [Member]	12 Months Ended
	Dec. 31, 2015
Debt Instrument [Line Items]
Interest rate on Senior Notes	5.25%
Senior Notes payable periods	Mar. 15, 2019

Long Term Debt - Summary of Ann

Long Term Debt - Summary of Annual Maturities of Long-term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
2,016	$ 0
2,017	57,500
2,018	0
2,019	500,000
2,020	0
Thereafter	0
Total	$ 557,500	$ 543,000

Long Term Debt - Additional Inf

Long Term Debt - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Proceeds from issuance of senior notes		$ 500,000,000
Carrying value of Long-term Debt	$ 557,500,000	543,000,000
Pretax charge related to early redemption of senior notes		(29,833,000)
Letters of credit outstanding under the facility	15,300,000	15,500,000
Letter of credit securing workers compensation policy	$ 2,600,000	2,500,000
Middle East [Member]
Debt Instrument [Line Items]
Revolving credit facility, maturity date	Oct. 29, 2016
Letter of credit securing contract in Middle East	$ 9,200,000
Middle East [Member] | Maximum [Member]
Debt Instrument [Line Items]
Letter of credit, extended period	1 year
5.25% Senior Notes due March 15, 2019 [Member]
Debt Instrument [Line Items]
Carrying value of Long-term Debt	$ 500,000,000	500,000,000
Fair market value of Senior Notes	$ 403,100,000	425,600,000
5.25% Senior Notes due March 15, 2019 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate on Senior Notes	5.25%
Debt instrument redemption date	On or after March 15, 2016
Percentage of principal amount redeemed	101.00%
Proceeds from issuance of senior notes		493,800,000
Carrying value of Long-term Debt	$ 500,000,000	$ 500,000,000
Eight Point Six Two Five Percent Senior Note Due Two Thousand Eighteen [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate on Senior Notes		8.625%
Carrying value of Long-term Debt		$ 300,000,000
Cost of debt repayment		329,400,000
Pretax charge related to early redemption of senior notes		(29,800,000)
Premium on early redemption of senior notes		26,700,000
Write off of unamortized financing costs		3,100,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Carrying value of Long-term Debt	57,500,000	$ 43,000,000
Increased Borrowing capacity	$ 150,000,000
Revolving credit facility, maturity date	Oct. 1, 2017
Revolving Credit facility, Covenants, consolidated working capital ratio	200.00%
Revolving Credit facility, Covenants, consolidated net worth ratio	150.00%
Revolving Credit facility, Covenants, fixed coverage ratio	110.00%
Revolving Credit facility, Covenants, consolidated net worth	$ 450,000,000
Letter of credit securing workers compensation policy	$ 6,100,000
Revolving Credit Facility [Member] | LIBOR [Member]
Debt Instrument [Line Items]
LIBOR plus interest rate on borrowed funds	225.00%

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current
Federal	$ 0	$ 0	$ 0
State	284	307	353
Foreign	3,159	4,352	9,637
Deferred - principally Federal	12,889	15,768	21,195
Total	$ 16,332	$ 20,427	$ 31,185

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes Disclosure [Line Items]
Federal Statutory rate	35.00%	35.00%	35.00%
Increase in total stake holders equity	$ 1,000,000
Operating loss carryforwards	$ 158,300,000
Operating loss carryforwards, expiration date start	2,028
Operating loss carryforwards, expiration date end	2,035
Net operating loss carryforwards, majority expiration date start	2,024
Net operating loss carryforwards, majority expiration date end	2,035
Valuation allowance - state NOL carryforwards	$ 290,000	$ 219,000
Foreign tax credits	$ 20,100,000
Foreign tax credits, expiration date start	2,016
Foreign tax credits, expiration date end	2,025
Valuation allowance - tax credit carryforwards	$ 2,000,000
Valuation allowance - tax credit carryforwards recorded in 2014	0
Income taxes paid	5,521,000	$ 9,590,000	$ 1,161,000
Unrecognized tax benefits	0
State and Local Jurisdiction [Member]
Income Taxes Disclosure [Line Items]
Operating loss carryforwards	$ 160,400,000
Operating loss carryforwards, expiration date end	2,035
Valuation allowance - state NOL carryforwards	$ 300,000
State and Local Jurisdiction [Member] | Valuation Allowance, Operating Loss Carryforwards [Member]
Income Taxes Disclosure [Line Items]
Valuation allowance - state NOL carryforwards	$ 100,000

Income Taxes - Schedule of In63

Income Taxes - Schedule of Income Tax Expense as Percentage of Pre-Tax Earnings (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Income taxes at statutory rate	35.00%	35.00%	35.00%
Valuation allowance on foreign tax credits	0.00%	0.00%	0.00%
Valuation allowance reversal-investment in foreign entity	(1.00%)
Change in tax rate on deferred items	3.00%		(4.00%)
State income taxes, net of federal benefit		2.00%	2.00%
Other items - net	1.00%	1.00%	2.00%
Total	38.00%	38.00%	35.00%
Income taxes at statutory rate	$ 15,140	$ 18,590	$ 31,550
Increase (decrease) in taxes resulting from:
Valuation allowance on foreign tax credits		113
Valuation allowance reversal-investment in foreign entity	(456)
Change in tax rate on deferred items	1,078		(3,850)
State income taxes, net of federal benefit	146	916	2,161
Other items - net	424	808	1,324
Total	$ 16,332	$ 20,427	$ 31,185

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, 2015	Dec. 31, 2014
Deferred tax assets:
Deferred compensation	$ 946	$ 1,023
Foreign tax credits	20,118	16,982
Vacation and bonus accrual	1,952	2,031
Inventory valuation	6,808	6,093
Rental accrual	1,691	1,799
Hurricane relief credit	1,255	1,255
Stock-based compensation	3,598	2,977
Other	3,593	2,714
Net operating losses	61,611	56,305
Total deferred tax assets	101,572	91,179
Valuation allowance - state NOL carryforwards	(290)	(219)
Valuation allowance - tax credit carryforwards	(2,047)	(2,047)
Valuation allowance - other		(1,466)
Total deferred tax assets, net	99,235	87,447
Deferred tax liabilities:
Tax depreciation in excess of book depreciation	(242,501)	(218,064)
Total deferred tax liabilities	(242,501)	(218,064)
Net deferred tax liabilities	(143,266)	(130,617)
Current deferred tax assets	10,379	9,915
Deferred tax liability - long-term	(153,645)	(140,532)
Net deferred tax liabilities	$ (143,266)	$ (130,617)

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, 2015	Dec. 31, 2014	Dec. 31, 2013
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Weighted average outstanding shares of common stock, basic	15,566	15,483	15,474
Dilutive effect of restricted stock units	76	202	165
Weighted average outstanding shares of common stock, diluted	15,642	15,685	15,639

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Anti-dilutive securities	0	0	0

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2015USD ($)CompensationPlan	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Defined Benefit Plan Disclosure [Line Items]
Aggregate deferred under Compensation Plan	$ 2.3	$ 2.4
Number of incentive compensation plans | CompensationPlan	3
Earnings before tax upon achieving a specified earnings threshold	8.25%
Accrued Incentive Compensation expense	$ 3	11.7	$ 11.5
Compensation expense related to incentive plans	$ 5.8	4.8	2.4
Percentage of employee compensation contribution	6.00%
Percentage of vesting contribution	25.00%
Vesting period of employees	5 years
Matching contribution of employees	$ 11.8	11.5	10.5
Safety Incentive Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Compensation expense related to incentive plans	$ 0.9	$ 1	$ 1

Stock-based Compensation - Addi

Stock-based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stock Based Compensation [Line Items]
Compensation expense related to incentive plans	$ 5,800,000	$ 4,800,000	$ 2,400,000
Non-Voting Time-Vested Restricted Stock Units [Member]
Stock Based Compensation [Line Items]
Weighted average grant date fair value	$ 30.17	$ 43.25
Aggregate value of vested shares	$ 900,000	$ 300,000
Recognized / Unrecognized compensation cost	$ 3,400,000
Weighted average period	1 year 6 months 22 days
Aggregate value of forfeited shares	$ 200,000	$ 0
Non-Voting Performance Based Restricted Stock Units [Member]
Stock Based Compensation [Line Items]
Weighted average grant date fair value	$ 33.41
Aggregate value of vested shares	$ 3,300,000
Recognized / Unrecognized compensation cost	$ 7,400,000
Weighted average period	1 year 9 months 29 days
Aggregate value of forfeited shares	$ 200,000
2012 Long - Term Incentive Plan [Member] | Amended and Restated 2015 Long Term Incentive Plan [Member]
Stock Based Compensation [Line Items]
Shares available for issuance	721,572
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	1,500,000

Stock-based Compensation - Summ

Stock-based Compensation - Summary of Activity for Non-voting Time-vested Restricted Stock (Detail) - Non-Voting Time-Vested Restricted Stock Units [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share unit, Beginning Balance	191,655
Share unit, Granted	35,456
Share unit, Forfeited	(8,026)
Share unit, Vested and released to participants	(37,610)
Share unit, Ending Balance	181,475	191,655
Weighted Average Grant Fair Value, Beginning Balance	$ 38.56
Weighted Average Grants Date Fair Value, Granted	30.17	$ 43.25
Weighted Average Grants Date Fair Value, Forfeited	(22.81)
Weighted Average Grants Date Fair Value, Vested and released to participants	(24.82)
Weighted Average Grant Fair Value, Ending Balance	$ 40.47	$ 38.56
Remaining Average Contractual Life, Ending	1 year 6 months 22 days	2 years 3 months 4 days
Aggregate Value, Beginning Balance	$ 7,391
Aggregate Value, Ending Balance	$ 7,344	$ 7,391

Stock-based Compensation - Su70

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, 2015	Dec. 31, 2014
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share unit, Beginning Balance	191,655
Share unit, Granted	35,456
Share unit, Forfeited	(8,026)
Share unit, Vested and released to participants	(37,610)
Share unit, Ending Balance	181,475	191,655
Weighted Average Grant Fair Value, Beginning Balance	$ 38.56
Weighted Average Grants Date Fair Value, Granted	30.17	$ 43.25
Weighted Average Grants Date Fair Value, Forfeited	22.81
Weighted Average Grants Date Fair Value, Vested and released to participants	(24.82)
Weighted Average Grant Fair Value, Ending Balance	$ 40.47	$ 38.56
Remaining Average Contractual Life, Ending	1 year 6 months 22 days	2 years 3 months 4 days
Aggregate Value, Beginning Balance	$ 7,391
Aggregate Value, Ending Balance	$ 7,344	$ 7,391
Director [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share unit, Beginning Balance	4,488
Share unit, Granted	4,317
Share unit, Forfeited	0
Share unit, Vested and released to participants	0
Share unit, Ending Balance	8,805	4,488
Weighted Average Grant Fair Value, Beginning Balance	$ 41.19
Weighted Average Grants Date Fair Value, Granted	21.42
Weighted Average Grants Date Fair Value, Forfeited	0
Weighted Average Grants Date Fair Value, Vested and released to participants	0
Weighted Average Grant Fair Value, Ending Balance	$ 31.50	$ 41.19
Remaining Average Contractual Life, Ending	2 years 2 months 16 days	2 years 5 months 23 days
Aggregate Value, Beginning Balance	$ 185
Aggregate Value, Ending Balance	$ 277	$ 185

Stock-based Compensation - Su71

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, 2015	Dec. 31, 2014
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Share unit, Beginning Balance	394,669
Share unit, Granted	152,331
Share unit, Forfeited	(10,758)
Share unit, Vested and released to participants	(141,286)
Share unit, Ending Balance	394,956	394,669
Weighted Average Grant Fair Value, Beginning Balance	$ 30.07
Weighted Average Grants Date Fair Value, Granted	33.41
Weighted Average Grants Date Fair Value, Forfeited	(22.81)
Weighted Average Grants Date Fair Value, Vested and released to participants	(23.04)
Weighted Average Grant Fair Value, Ending Balance	$ 34.07	$ 30.07
Remaining Average Contractual Life, Ending	1 year 9 months 29 days	1 year 9 months 11 days
Aggregate Value, Beginning Balance	$ 11,878
Aggregate Value, Ending Balance	$ 13,456	$ 11,878

Commitments and Contingencies -

Commitments and Contingencies - Summary of Rental Expense Incurred Under Leases (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]
Aircraft	$ 45,360	$ 44,908	$ 41,803
Other	8,358	7,790	7,657
Total	$ 53,718	$ 52,698	$ 49,460

Commitments and Contingencies73

Commitments and Contingencies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)AircraftLand_Parcel	Dec. 31, 2014USD ($)Aircraft	Dec. 31, 2013USD ($)
Long-term Purchase Commitment [Line Items]
Aircraft and real estate rental expense	$ 53,718	$ 52,698	$ 49,460
Aggregate amount of guarantees and bonds	$ 1,100
Number of aircrafts delivered | Aircraft	1
Total aircraft deposits	$ 3,568	8,305
Aggregate estimated probable liability environmental matters	$ 200
Number of parcels of land exists | Land_Parcel	2
Affiliated Entity [Member]
Long-term Purchase Commitment [Line Items]
Aircraft and real estate rental expense	$ 0	$ 500	$ 600
2016 [Member]
Long-term Purchase Commitment [Line Items]
Aggregate purchase price for aircraft	67,800
2017 [Member]
Long-term Purchase Commitment [Line Items]
Aggregate purchase price for aircraft	55,700
2018 [Member]
Long-term Purchase Commitment [Line Items]
Aggregate purchase price for aircraft	127,000
2019 [Member]
Long-term Purchase Commitment [Line Items]
Aggregate purchase price for aircraft	150,400
2020 [Member]
Long-term Purchase Commitment [Line Items]
Aggregate purchase price for aircraft	22,700
Heavy Aircraft [Member]
Long-term Purchase Commitment [Line Items]
Aggregate purchase price for aircraft	$ 17,700
Number of aircraft purchased | Aircraft	1
Option to purchase additional number of aircrafts | Aircraft		6
Number of aircraft orders cancelled previously scheduled for delivery | Aircraft	4

Commitments and Contingencies74

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, 2015USD ($)
Operating Leased Assets [Line Items]
2,016	$ 50,293
2,017	45,892
2,018	41,570
2,019	34,348
2,020	29,939
Thereafter	90,349
Total	292,391
Aircraft [Member]
Operating Leased Assets [Line Items]
2,016	44,988
2,017	42,699
2,018	39,018
2,019	32,365
2,020	28,526
Thereafter	89,604
Total	277,200
Other [Member]
Operating Leased Assets [Line Items]
2,016	5,305
2,017	3,193
2,018	2,552
2,019	1,983
2,020	1,413
Thereafter	745
Total	$ 15,191

Business Segments and Geograp75

Business Segments and Geographic Areas - Schedule of Accounts Receivable and Revenue by Major Customers by Reporting Segments (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Customer Concentration Risk [Member] | Oil and Gas [Member] | Sales Revenue, Segment [Member] | Customer A [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	15.00%	17.00%	15.00%
Customer Concentration Risk [Member] | Oil and Gas [Member] | Sales Revenue, Segment [Member] | Customer B [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	11.00%	13.00%	13.00%
Customer Concentration Risk [Member] | Air Medical and Technical Services [Member] | Sales Revenue, Segment [Member] | Customer C [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	9.00%	10.00%	17.00%
Concentration of Credit Risk [Member] | Oil and Gas [Member] | Accounts Receivable [Member] | Customer A [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	6.00%	7.00%
Concentration of Credit Risk [Member] | Oil and Gas [Member] | Accounts Receivable [Member] | Customer B [Member]
Revenue, Major Customer [Line Items]
Concentration risk, percentage	9.00%	12.00%
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	15.00%	20.00%

Business Segments and Geograp76

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, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Total operating revenues		$ 186,751	$ 214,733	$ 198,547	$ 204,197	$ 210,760	$ 216,294	$ 212,145	$ 197,071	$ 804,228	$ 836,270	$ 856,500
Total segment direct expenses										687,050	670,007	713,090
Total segment selling, general and administrative expenses										46,422	43,171	38,820
Total										70,111	111,640	119,284
Interest expense										(29,066)	(29,510)	(29,756)
Loss on debt extinguishment											(29,833)
Earnings before income taxes		$ 938	$ 14,290	$ 11,044	$ 16,984	$ 11,651	$ 28,277	$ 21,700	$ (8,513)	43,256	53,115	90,141
Reportable Operating Segments [Member]
Segment Reporting Information [Line Items]
Total operating revenues										804,228	836,270	856,500
Total segment direct expenses										687,356	670,103	713,352
Total segment selling, general and administrative expenses										17,771	14,573	12,935
Total segment expenses										705,127	684,676	726,287
Total										99,101	151,594	130,213
Reportable Operating Segments [Member] | Air Medical [Member]
Segment Reporting Information [Line Items]
Total operating revenues										312,775	300,212	277,884
Total segment direct expenses										246,487	243,573	231,880
Total segment selling, general and administrative expenses	[1]									10,455	9,801	8,875
Total										55,833	46,838	37,129
Interest expense												(300)
Reportable Operating Segments [Member] | Oil and Gas [Member]
Segment Reporting Information [Line Items]
Total operating revenues										459,611	516,909	489,055
Total segment direct expenses	[2]									411,757	411,679	393,251
Total segment selling, general and administrative expenses										6,511	4,615	4,059
Total										41,343	100,615	91,745
Reportable Operating Segments [Member] | Technical Services [Member]
Segment Reporting Information [Line Items]
Total operating revenues										31,842	19,149	89,561
Total segment direct expenses										29,112	14,851	88,221
Total segment selling, general and administrative expenses										805	157	1
Total										1,925	4,141	1,339
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Other, net	[3]									1,872	(10,539)	15,569
Interest expense										(29,066)	(29,510)	(29,434)
Corporate [Member]
Segment Reporting Information [Line Items]
Unallocated selling, general and administrative costs										$ (28,651)	$ (28,597)	$ (26,207)
[1]	Includes interest expense $0.3 million for the year ended December 31, 2013.
[2]	Includes equity in loss of unconsolidated affiliate.
[3]	Includes gains on disposition of property and equipment and other income.

Business Segments and Geograp77

Business Segments and Geographic Areas - Schedule of Financial Information Concerning Reportable Operating Segments (Parenthetical) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Interest expense	$ 29,066	$ 29,510	$ 29,756
Air Medical [Member] | Reportable Operating Segments [Member]
Segment Reporting Information [Line Items]
Interest expense			$ 300

Business Segments and Geograp78

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, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting, Asset Reconciling Item [Line Items]
Expenditures for long-lived assets	$ 56,575	$ 157,705	$ 102,590
Depreciation and amortization	71,618	50,848	42,848
Total assets	1,430,332	1,376,080
Reportable Operating Segments [Member] | Oil and Gas [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Expenditures for long-lived assets	32,501	119,235	62,934
Depreciation and amortization	42,709	29,635	26,653
Total assets	704,472	726,008
Reportable Operating Segments [Member] | Air Medical [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Expenditures for long-lived assets	22,685	37,317	37,728
Depreciation and amortization	18,177	13,067	11,395
Total assets	329,484	336,510
Reportable Operating Segments [Member] | Technical Services [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Depreciation and amortization	518	493	172
Total assets	7,345	7,842
Corporate [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Expenditures for long-lived assets	1,389	1,153	1,928
Depreciation and amortization	10,214	7,653	$ 4,628
Total assets	$ 389,031	$ 305,720

Business Segments and Geograp79

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, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Total operating revenues	$ 186,751	$ 214,733	$ 198,547	$ 204,197	$ 210,760	$ 216,294	$ 212,145	$ 197,071	$ 804,228	$ 836,270	$ 856,500
Total Long-Lived Assets	883,529				877,818				883,529	877,818
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total operating revenues									722,339	747,063	699,298
Total Long-Lived Assets	773,939				846,377				773,939	846,377
International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total operating revenues									81,889	89,207	$ 157,202
Total Long-Lived Assets	$ 109,590				$ 31,441				$ 109,590	$ 31,441

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, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Operating revenues	$ 186,751	$ 214,733	$ 198,547	$ 204,197	$ 210,760	$ 216,294	$ 212,145	$ 197,071	$ 804,228	$ 836,270	$ 856,500
Gain (loss) on disposition of assets, net	(577)	165	66	7	523	(56)	(242)	(1,073)	(339)	(848)	16,604
Earnings (loss) before income taxes	938	14,290	11,044	16,984	11,651	28,277	21,700	(8,513)	43,256	53,115	90,141
Net earnings (loss)	$ 2,438	$ 7,669	$ 6,454	$ 10,363	$ 7,392	$ 17,249	$ 13,368	$ (5,321)	$ 26,924	$ 32,688	$ 58,956
Net earnings (loss) per share
Basic	$ 0.16	$ 0.49	$ 0.41	$ 0.67	$ 0.48	$ 1.11	$ 0.86	$ (0.34)
Diluted	$ 0.16	$ 0.49	$ 0.41	$ 0.66	$ 0.47	$ 1.10	$ 0.85	$ (0.34)

Variable Interest Entity - Addi

Variable Interest Entity - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Variable Interest Entity [Line Items]
Earnings (loss) in equity of unconsolidated affiliate	$ (300)	$ 100
Trade receivables	1,500	2,800
Accrued and other current liabilities	44,759	52,812
Other assets	0	0
Operating revenue	$ 0	3,400
PHIC's date of incorporation	May 26, 2011
PHI Century Limited [Member]
Variable Interest Entity [Line Items]
Investment in the common stock	49.00%
Accrued and other current liabilities		$ 900
Allowance for Trade Receivables [Member]
Variable Interest Entity [Line Items]
Allowance for bad debts against trade receivables	$ 1,500

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2016USD ($)RetirementPlansEmployees	Dec. 31, 2015RetirementPlans
Subsequent Event [Line Items]
Number of voluntary employee retirement program (VERP) | RetirementPlans		3
Subsequent Event [Member]
Subsequent Event [Line Items]
Number of voluntary employee retirement program (VERP) | RetirementPlans	1
Subsequent Event [Member] | Voluntary Employee Retirement Package [Member]
Subsequent Event [Line Items]
Qualifying age	64 years
Subsequent Event [Member] | Voluntary Employee Retirement Package [Member] | Maximum [Member]
Subsequent Event [Line Items]
Severance costs | $	$ 3.1
Subsequent Event [Member] | Voluntary Furlough Program [Member]
Subsequent Event [Line Items]
Severance costs | $	$ 0.4
Number of employees accepted VERP | Employees	26

Condensed Consolidating Finan83

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Additional Information (Detail)	Dec. 31, 2015
Supplemental Guarantor Financial Information [Line Items]
Ownership percentage in domestic subsidiaries	100.00%
5.25% Senior Notes due March 15, 2019 [Member] | Senior Notes [Member]
Supplemental Guarantor Financial Information [Line Items]
Interest rate on Senior Notes	5.25%

Condensed Consolidating Finan84

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidating Balance Sheets (Detail) - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013		Dec. 31, 2012
Current Assets:
Cash		$ 2,407	$ 6,270	$ 934		$ 2,849
Short-term investments		284,523	185,244
Accounts receivable - net		144,778	180,761
Inventories of spare parts - net		69,491	73,793
Prepaid expenses		8,951	9,314
Deferred income taxes		10,379	9,915
Income taxes receivable		761	1,227
Total current assets		521,290	466,524
Property and equipment, net		883,529	877,818
Restricted investments		15,336	15,485
Other assets		10,177	16,253
Total assets		1,430,332	1,376,080
Current Liabilities:
Accounts payable		31,373	27,700
Accrued and other current liabilities		44,759	52,812
Total current liabilities		76,132	80,512
Long-term debt		557,500	543,000
Deferred income taxes and other long-term liabilities		169,702	155,500
Shareholders' Equity:
Common stock and paid-in capital		306,444	303,082
Accumulated other comprehensive loss		(567)	(211)
Retained earnings		321,121	294,197
Total shareholders' equity		626,998	597,068	559,965		499,615
Total liabilities and shareholders' equity		1,430,332	1,376,080
Parent Company Only (issuer) [Member]
Current Assets:
Cash		46	51	52		552
Short-term investments		284,523	185,244
Accounts receivable - net		70,336	98,001
Inventories of spare parts - net		60,060	65,341
Prepaid expenses		7,162	7,610
Deferred income taxes		10,379	9,915
Income taxes receivable		1,002	1,068
Total current assets		433,508	367,230
Investment in subsidiaries		330,848	358,080
Property and equipment, net		632,759	638,437
Restricted investments		15,336	15,485
Other assets		9,974	16,055
Total assets		1,422,425	1,395,287
Current Liabilities:
Accounts payable		25,512	22,578
Accrued and other current liabilities		29,138	34,477
Intercompany payable		90,943	95,270
Total current liabilities		145,593	152,325
Long-term debt		557,500	543,000
Deferred income taxes and other long-term liabilities		92,334	102,894
Shareholders' Equity:
Common stock and paid-in capital		306,444	303,082
Accumulated other comprehensive loss		(567)	(211)
Retained earnings		321,121	294,197
Total shareholders' equity		626,998	597,068
Total liabilities and shareholders' equity		1,422,425	1,395,287
Guarantor Subsidiaries [Member]
Current Assets:
Cash	[1]	2,361	6,219	$ 882	[2]	$ 2,297	[2]
Accounts receivable - net	[1]	74,442	82,760
Intercompany receivable	[1]	90,943	95,399
Inventories of spare parts - net	[1]	9,431	8,452
Prepaid expenses	[1]	1,789	1,704
Income taxes receivable	[1]	(241)	159
Total current assets	[1]	178,725	194,693
Property and equipment, net	[1]	250,770	239,381
Other assets	[1]	203	198
Total assets	[1]	429,698	434,272
Current Liabilities:
Accounts payable	[1]	5,861	5,122
Accrued and other current liabilities	[1]	15,621	18,335
Total current liabilities	[1]	21,482	23,457
Deferred income taxes and other long-term liabilities	[1]	77,368	52,606
Shareholders' Equity:
Common stock and paid-in capital	[1]	79,061	137,647
Retained earnings	[1]	251,787	220,562
Total shareholders' equity	[1]	330,848	358,209
Total liabilities and shareholders' equity	[1]	429,698	434,272
Eliminations [Member]
Current Assets:
Intercompany receivable		(90,943)	(95,399)
Total current assets		(90,943)	(95,399)
Investment in subsidiaries		(330,848)	(358,080)
Total assets		(421,791)	(453,479)
Current Liabilities:
Intercompany payable		(90,943)	(95,270)
Total current liabilities		(90,943)	(95,270)
Shareholders' Equity:
Common stock and paid-in capital		(79,061)	(137,647)
Retained earnings		(251,787)	(220,562)
Total shareholders' equity		(330,848)	(358,209)
Total liabilities and shareholders' equity		$ (421,791)	$ (453,479)
[1]	Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries' amounts.
[2]	Cash flows between the Parent Company and guarantor subsidiaries related to the Company's centralized cash management activities in 2013 have been adjusted to show the effects on net cash provided by operating and financing activities.

Condensed Consolidating Finan85

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidating Statements of Operations (Detail) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Income Statements, Captions [Line Items]
Operating revenues, net		$ 186,751	$ 214,733	$ 198,547	$ 204,197	$ 210,760	$ 216,294	$ 212,145	$ 197,071	$ 804,228	$ 836,270	$ 856,500
Expenses:
Direct expenses										687,050	670,007	713,090
Selling, general, and administrative expenses										46,422	43,171	38,820
Total operating expenses										733,472	713,178	751,910
Loss (gain) on disposition of assets, net		577	(165)	(66)	(7)	(523)	56	242	1,073	339	848	(16,604)
Impairment of assets											10,508	1,648
Equity in loss of unconsolidated affiliate										306	96	262
Operating income										70,111	111,640	119,284
Interest expense										29,066	29,510	29,756
Loss on debt extinguishment											29,833
Other (income) expense, net										(2,211)	(818)	(613)
Total expenses										26,855	58,525	29,143
Earnings before income taxes		938	14,290	11,044	16,984	11,651	28,277	21,700	(8,513)	43,256	53,115	90,141
Income tax (benefit) expense										16,332	20,427	31,185
Net earnings		$ 2,438	$ 7,669	$ 6,454	$ 10,363	$ 7,392	$ 17,249	$ 13,368	$ (5,321)	26,924	32,688	58,956
Parent Company Only (issuer) [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues, net										476,969	504,180	564,445
Expenses:
Direct expenses										426,239	411,398	468,321
Selling, general, and administrative expenses										35,694	32,985	29,885
Management fees												(11,682)
Total operating expenses										461,933	444,383	486,524
Loss (gain) on disposition of assets, net										339	848	(16,585)
Impairment of assets											10,508	1,227
Equity in loss of unconsolidated affiliate										306	96	262
Operating income										14,391	48,345	93,017
Equity in net earnings of consolidated subsidiaries										(31,225)	(38,740)	(15,567)
Interest expense										28,946	29,510	29,434
Loss on debt extinguishment											29,833
Other (income) expense, net										(2,222)	(819)	(613)
Total expenses										(4,501)	19,784	13,254
Earnings before income taxes										18,992	28,561	79,763
Income tax (benefit) expense										(8,032)	(4,127)	20,807
Net earnings										26,924	32,688	58,956
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Operating revenues, net	[1]									327,259	332,090	292,055
Expenses:
Direct expenses	[1]									260,829	258,627	244,769
Selling, general, and administrative expenses	[1]									10,728	10,186	8,935
Management fees	[1]											11,682
Total operating expenses	[1]									271,557	268,813	265,386
Loss (gain) on disposition of assets, net	[1]											(19)
Impairment of assets	[1]											421
Operating income	[1]									55,702	63,277	26,267
Interest expense	[1]									120		322
Other (income) expense, net	[1]									(7)	(17)
Total expenses	[1]									113	(17)	322
Earnings before income taxes	[1]									55,589	63,294	25,945
Income tax (benefit) expense	[1]									24,364	24,554	10,378
Net earnings	[1]									31,225	38,740	15,567
Eliminations [Member]
Expenses:
Direct expenses										(18)	(18)
Total operating expenses										(18)	(18)
Operating income										18	18
Equity in net earnings of consolidated subsidiaries										31,225	38,740	15,567
Other (income) expense, net										18	18
Total expenses										31,243	38,758	15,567
Earnings before income taxes										(31,225)	(38,740)	(15,567)
Net earnings										$ (31,225)	$ (38,740)	$ (15,567)
[1]	Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries' amounts.

Condensed Consolidating Finan86

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidating Statements of Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Net earnings		$ 2,438	$ 7,669	$ 6,454	$ 10,363	$ 7,392	$ 17,249	$ 13,368	$ (5,321)	$ 26,924	$ 32,688	$ 58,956
Unrealized gain (loss) on short-term investments										(641)	(285)	44
Other unrealized gain (loss)										24	(24)
Changes in pension plan assets and benefit obligations										7	17	(2)
Tax impact										254	105	(15)
Total Comprehensive Income (Loss)										26,568	32,501	58,983
Parent Company Only (issuer) [Member]
Condensed Financial Statements, Captions [Line Items]
Net earnings										26,924	32,688	58,956
Unrealized gain (loss) on short-term investments										(641)	(285)	44
Other unrealized gain (loss)										24	(24)
Changes in pension plan assets and benefit obligations										7	17	(2)
Tax impact										254	105	(15)
Total Comprehensive Income (Loss)										26,568	32,501	58,983
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net earnings	[1]									31,225	38,740	15,567
Total Comprehensive Income (Loss)	[1]									31,225	38,740	15,567
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net earnings										(31,225)	(38,740)	(15,567)
Total Comprehensive Income (Loss)										$ (31,225)	$ (38,740)	$ (15,567)
[1]	Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries' amounts.

Condensed Consolidating Finan87

Condensed Consolidating Financial Information - Guarantor Subsidiaries - Condensed Consolidating Statements of Cash Flows (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014		Dec. 31, 2013
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities		$ 133,918	$ 119,519		$ 105,096
Investing activities:
Purchase of property and equipment		(57,123)	(157,690)		(102,726)
Proceeds from asset dispositions		5,236	10,266		42,197
Purchase of short-term investments		(608,649)	(465,094)		(375,503)
Proceeds from sale of short-term investments		505,966	363,110		338,970
Refund of deposits on aircraft		6,010	11,506		8,161
Payments of deposits on aircraft		(1,273)	(6,948)		(9,318)
Loan to unconsolidated affiliate			(200)
Net cash used in investing activities		(149,833)	(245,050)		(98,219)
Financing activities:
Proceeds from issuance of Senior Notes due 2019			500,000
Repayment of Senior Notes due 2018			(300,000)
Premium and cost to retire debt early			(26,749)
Debt issuance costs			(6,232)
Proceeds from line of credit		232,660	264,253		164,771
Payments on line of credit		(218,160)	(300,253)		(172,526)
Repurchase of common stock		(2,448)	(152)		(1,037)
Net cash provided by (used in) financing activities		12,052	130,867		(8,792)
(Decrease) increase in cash		(3,863)	5,336		(1,915)
Cash, beginning of year		6,270	934		2,849
Cash, end of year		2,407	6,270		934
Parent Company Only (issuer) [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities		60,241	51,476		82,660
Investing activities:
Purchase of property and equipment		(57,123)	(157,690)		(102,726)
Proceeds from asset dispositions		5,236	10,266		42,197
Purchase of short-term investments		(608,649)	(465,094)		(375,503)
Proceeds from sale of short-term investments		505,966	363,110		338,970
Refund of deposits on aircraft		6,010	11,506		8,161
Payments of deposits on aircraft		(1,273)	(6,948)		(9,318)
Loan to unconsolidated affiliate			(200)
Net cash used in investing activities		(149,833)	(245,050)		(98,219)
Financing activities:
Proceeds from issuance of Senior Notes due 2019			500,000
Repayment of Senior Notes due 2018			(300,000)
Premium and cost to retire debt early			(26,749)
Debt issuance costs			(6,232)
Proceeds from line of credit		232,660	264,253		164,771
Payments on line of credit		(218,160)	(300,253)		(172,526)
Repurchase of common stock		(2,448)	(152)		(1,037)
Due to/from affiliate, net		77,535	62,706		23,851
Net cash provided by (used in) financing activities		89,587	193,573		15,059
(Decrease) increase in cash		(5)	(1)		(500)
Cash, beginning of year		51	52		552
Cash, end of year		46	51		52
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities	[1]	73,677	68,043		22,436	[2]
Financing activities:
Due to/from affiliate, net	[1]	(77,535)	(62,706)		(23,851)	[2]
Net cash provided by (used in) financing activities	[1]	(77,535)	(62,706)		(23,851)	[2]
(Decrease) increase in cash	[1]	(3,858)	5,337		(1,415)	[2]
Cash, beginning of year	[1]	6,219	882	[2]	2,297	[2]
Cash, end of year	[1]	$ 2,361	$ 6,219		$ 882	[2]
[1]	Foreign subsidiaries represent minor subsidiaries and are included in the guarantor subsidiaries' amounts.
[2]	Cash flows between the Parent Company and guarantor subsidiaries related to the Company's centralized cash management activities in 2013 have been adjusted to show the effects on net cash provided by operating and financing activities.

Schedule II - Valuation and Q88

Schedule II - Valuation and Qualifying Consolidated Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Doubtful Accounts, Current [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 1,351	$ 1,001	$ 50
Additions Charged to Costs and Expenses	3,800	350	951
Balance at End of Year	5,151	1,351	1,001
Allowance for Inventory [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	13,517	12,292	12,361
Additions Charged to Costs and Expenses	1,868	1,225
Deductions			69
Balance at End of Year	15,385	13,517	12,292
Allowance for Contractual Discounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	96,590	74,711	50,389
Additions Charged to Costs and Expenses	439,991	408,362	312,927
Deductions	432,980	386,483	288,605
Balance at End of Year	103,601	96,590	74,711
Allowance for Uncompensated Care [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	41,858	46,387	52,168
Additions Charged to Costs and Expenses	84,470	79,564	71,011
Deductions	84,404	84,093	76,792
Balance at End of Year	$ 41,924	$ 41,858	$ 46,387