Alliance HealthCare Services (AIQ) 10-K 10 Mar 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Mar. 01, 2017	Jun. 30, 2016
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Trading Symbol	AIQ
Entity Registrant Name	Alliance HealthCare Services, Inc
Entity Central Index Key	817,135
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		10,812,964
Entity Public Float			$ 30.5
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 22,241	$ 38,070
Accounts receivable, net of allowance for doubtful accounts of $4,008 in 2016 and $5,461 in 2015	77,496	73,208
Prepaid expenses	9,568	13,463
Other current assets	3,853	3,206
Total current assets	113,158	127,947
Plant, property and equipment, net	204,814	177,188
Goodwill	119,130	102,782
Other intangible assets, net	198,977	162,923
Other assets	23,785	32,820
Total assets	659,864	603,660
Current liabilities:
Accounts payable	28,185	20,796
Accrued compensation and related expenses	24,895	19,933
Accrued interest payable	3,308	3,323
Current portion of long-term debt	17,298	17,732
Current portion of obligations under capital leases	3,354	2,674
Other accrued liabilities	29,323	36,453
Total current liabilities	106,363	100,911
Long-term debt, net of current portion	515,407	540,353
Obligations under capital leases, net of current portion	12,686	10,332
Deferred income taxes	25,818	23,020
Other liabilities	9,093	6,664
Total liabilities	669,367	681,280
Commitments and contingencies (Note 12)
Stockholders’ deficit:
Preferred stock, $0.01 par value; 1,000,000 shares authorized and no shares issued and outstanding	0	0
Common stock, $0.01 par value; 100,000,000 shares authorized; 10,970,937 and 10,774,857 issued in 2016 and 2015, respectively; 10,812,964 and 10,616,884 outstanding in 2016 and 2015, respectively	110	108
Treasury stock, at cost - 157,973 shares in 2016 and 2015	(3,138)	(3,138)
Additional paid-in capital	61,353	29,297
Accumulated comprehensive income (loss)	10	(511)
Accumulated deficit	(197,900)	(198,393)
Total stockholders’ deficit attributable to Alliance HealthCare Services, Inc.	(139,565)	(172,637)
Noncontrolling interest	130,062	95,017
Total stockholders’ deficit	(9,503)	(77,620)
Total liabilities and stockholders’ deficit	$ 659,864	$ 603,660

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts	$ 4,008	$ 5,461
Preferred stock, par value (dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (shares)	1,000,000	1,000,000
Preferred stock, shares issued (shares)	0	0
Preferred stock, shares outstanding (shares)	0	0
Common stock, par value (dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (shares)	100,000,000	100,000,000
Common stock, shares issued (shares)	10,970,937	10,774,857
Common stock, shares outstanding (shares)	10,812,964	10,616,884
Treasury stock, shares (shares)	157,973	157,973

Consolidated Statements of Inco

Consolidated Statements of Income and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Revenues	$ 505,549	$ 473,054	$ 436,387
Costs and expenses:
Cost of revenues, excluding depreciation and amortization	285,746	269,104	237,420
Selling, general and administrative expenses	96,663	88,471	79,903
Transaction costs	1,886	3,296	2,344
Shareholder transaction costs	4,219	1,853	0
Severance and related costs	3,910	1,347	2,517
Impairment charges	632	6,817	308
Depreciation expense	54,972	48,595	54,971
Amortization expense	10,561	9,325	7,880
Interest expense, net	34,506	26,241	24,693
Other income, net	(6,586)	(12,255)	(1,823)
Total costs and expenses	486,509	442,794	408,213
Income before income taxes, earnings from unconsolidated investees, and noncontrolling interest	19,040	30,260	28,174
Income tax expense	2,852	6,536	7,327
Earnings from unconsolidated investees	(1,290)	(3,391)	(4,654)
Net income	17,478	27,115	25,501
Less: Net income attributable to noncontrolling interest	(16,985)	(20,373)	(14,883)
Net income attributable to Alliance HealthCare Services, Inc.	493	6,742	10,618
Comprehensive income, net of taxes:
Net income	17,478	27,115	25,501
Unrealized gain (loss) on hedging transactions, net of taxes of $59, $(68) and $(216)	104	(178)	(335)
Reclassification adjustment for losses included in net income, net of taxes of $236, $7 and $43	417	18	66
Comprehensive income, net of taxes	17,999	26,955	25,232
Less: Comprehensive income attributable to noncontrolling interest	(16,985)	(20,373)	(14,883)
Comprehensive income attributable to Alliance HealthCare Services, Inc.	$ 1,014	$ 6,582	$ 10,349
Income per common share attributable to Alliance HealthCare Services, Inc.:
Basic	$ 0.05	$ 0.63	$ 1
Diluted	$ 0.04	$ 0.62	$ 0.98
Weighted average number of shares of common stock and common stock equivalents:
Basic	10,866	10,741	10,669
Diluted	10,959	10,849	10,836

Consolidated Statements of Inc5

Consolidated Statements of Income and Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Unrealized gain (loss) on hedging transactions, tax	$ 59	$ (68)	$ (216)
Reclassification adjustment for losses included in net income, tax	$ 236	$ 7	$ 43

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities:
Net income	$ 17,478	$ 27,115	$ 25,501
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for doubtful accounts	2,255	2,911	2,634
Share-based payment	2,713	1,701	1,515
Depreciation and amortization	65,533	57,920	62,851
Amortization of deferred financing costs	8,126	2,554	1,926
Accretion of discount on long-term debt	513	481	447
Adjustment of derivatives to fair value	727	29	342
Distributions from unconsolidated investees	1,335	3,880	5,245
Earnings from unconsolidated investees	(1,290)	(3,391)	(4,654)
Deferred income taxes	1,780	6,350	6,582
Gain on sale of assets, net	(1,133)	(1,883)	(565)
Changes in fair value of contingent consideration related to acquisitions	(4,790)	0	0
Non-cash gain on step acquisition	0	(10,672)	0
Other non-cash gain	(423)	(209)	0
Impairment charges	632	6,817	308
Excess tax benefit from share-based payment arrangements	(100)	5	(623)
Changes in operating assets and liabilities, net of the effects of acquisitions:
Accounts receivable	(6,270)	(7,112)	(1,424)
Prepaid expenses	3,567	(877)	(5,064)
Other current assets	1,267	1,494	(114)
Other assets	(881)	2,607	(1,852)
Accounts payable	8,040	3,442	953
Accrued compensation and related expenses	4,962	(1,363)	(1,358)
Accrued interest payable	(15)	168	1,509
Income taxes payable	868	40	31
Other accrued liabilities	3,888	454	6,439
Net cash provided by operating activities	108,782	92,461	100,629
Investing activities:
Equipment purchases	(56,401)	(55,511)	(32,236)
Increase in deposits on equipment	(11,768)	(15,751)	(9,228)
Acquisitions, net of cash received	(25,912)	(49,140)	(16,043)
Increase in notes receivable	0	0	(2,776)
Proceeds from sale of assets	1,830	1,941	1,557
Net cash used in investing activities	(92,251)	(118,461)	(58,726)
Financing activities:
Principal payments on equipment debt and capital lease obligations	(16,925)	(12,697)	(10,368)
Proceeds from equipment debt	7,101	27,049	4,527
Principal payments on term loan facility	(5,200)	(9,951)	(4,900)
Proceeds from term loan facility	0	29,850	0
Principal payments on revolving loan facility	(61,000)	(33,000)	(45,000)
Proceeds from revolving loan facility	63,000	50,500	28,000
Payments of debt issuance costs and deferred financing costs	(25,741)	(808)	0
Distributions to noncontrolling interest in subsidiaries	(23,526)	(21,659)	(16,970)
Contributions from noncontrolling interest in subsidiaries	1,411	1,732	881
Issuance of common stock	1	1	0
Equity purchase of noncontrolling interest	0	0	(691)
Excess tax benefit from share-based payment arrangements	100	(5)	623
Proceeds from exercise of stock options	614	25	466
Purchase of treasury stock	0	0	(140)
Settlement of contingent consideration related to acquisitions	(825)	0	0
Proceeds from shareholder transaction	28,630	0	0
Net cash (used in) provided by financing activities	(32,360)	31,037	(43,572)
Net (decrease) increase in cash and cash equivalents	(15,829)	5,037	(1,669)
Cash and cash equivalents, beginning of period	38,070	33,033	34,702
Cash and cash equivalents, end of period	22,241	38,070	33,033
Supplemental disclosure of cash flow information:
Interest paid	25,368	23,373	21,037
Income taxes (refunded) paid, net of payments (refunds)	(3,852)	(664)	6,504
Supplemental disclosure of non-cash investing and financing activities:
Net book value of assets exchanged	170	199	0
Capital lease obligations related to the purchase of equipment	6,558	11,273	1,725
Changes in equipment purchases in accounts payable and accrued equipment	(4,591)	3,700	834
Extinguishment of note receivable (Note 3)	0	3,071	0
Transfer of equity investment as consideration in step acquisition (Note 3)	0	721	0
Transfer of assets as consideration in acquisitions (Note 3)	9,900	477	0
Transfer of fair value of equity investment in step acquisition (Note 3)	0	13,645	0
Noncontrolling interest assumed in connection with acquisitions (Note 3)	39,141	36,231	13,014
Mandatorily redeemable noncontrolling interest in connection with acquisition (Note 3)	0	2,386	0
Fair value of contingent consideration related to acquisitions (Note 5)	420	5,750	0
Debt related to purchase of equipment	0	0	3,183
Adjustment to equity of noncontrolling interest	$ 0	$ 0	$ 1,700

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Accumulated Comprehensive (Loss) Income	(Accumulated Deficit) Retained Earnings	Alliance HealthCare Services, Inc.	Non-controlling Interest
Beginning balance at Dec. 31, 2013	$ (147,661)	$ 524	$ (2,998)	$ 23,521	$ (82)	$ (215,753)	$ (194,788)	$ 47,127
Beginning balance, shares at Dec. 31, 2013		10,667,136	(144,921)
Exercise of stock options	467	$ 1		466			467
Exercise of common stock options, shares		72,794
Forfeiture of restricted stock, shares		(26,272)
Purchase of treasury stock	(140)		$ (140)				(140)
Purchase of treasury stock (shares)			(13,052)
Share-based payment	1,515			1,515			1,515
Share-based payment income tax benefit (detriment)	82			82			82
Other comprehensive income (loss)	(269)				(269)		(269)
Noncontrolling interest disposed in connection with acquisition	1,651			1,651			1,651
Net distributions to noncontrolling interest in subsidiaries	(3,670)							(3,670)
Other		$ (418)		418
Net income	25,501					10,618	10,618	14,883
Ending balance at Dec. 31, 2014	(122,524)	$ 107	$ (3,138)	27,653	(351)	(205,135)	(180,864)	58,340
Ending balance, shares at Dec. 31, 2014		10,713,658	(157,973)
Exercise of stock options	25			25			25
Exercise of common stock options, shares		2,515
Release of vested restricted stock / Vesting of stock awards	1	$ 1					1
Release of vested restricted stock / Vesting of stock awards (shares)		58,684
Share-based payment	1,701			1,701			1,701
Share-based payment income tax benefit (detriment)	(82)			(82)			(82)
Other comprehensive income (loss)	(160)				(160)		(160)
Net investments in subsidiaries / contributions from noncontrolling interest in subsidiaries	16,304							16,304
Net income	27,115					6,742	6,742	20,373
Ending balance at Dec. 31, 2015	(77,620)	$ 108	$ (3,138)	29,297	(511)	(198,393)	(172,637)	95,017
Ending balance, shares at Dec. 31, 2015		10,774,857	(157,973)
Exercise of stock options	$ 615	$ 1		614			615
Exercise of common stock options, shares	121,667	121,667
Release of vested restricted stock / Vesting of stock awards		$ 1		(1)
Release of vested restricted stock / Vesting of stock awards (shares)		74,413
Shareholder transaction	$ 28,630			28,630			28,630
Share-based payment	2,713			2,713			2,713
Share-based payment income tax benefit (detriment)	100			100			100
Other comprehensive income (loss)	521				521		521
Noncontrolling interest assumed in connection with acquisition	39,141							39,141
Net distributions to noncontrolling interest in subsidiaries	(23,526)							(23,526)
Net investments in subsidiaries / contributions from noncontrolling interest in subsidiaries	2,445							2,445
Net income	17,478					493	493	16,985
Ending balance at Dec. 31, 2016	$ (9,503)	$ 110	$ (3,138)	$ 61,353	$ 10	$ (197,900)	$ (139,565)	$ 130,062
Ending balance, shares at Dec. 31, 2016		10,970,937	(157,973)

Description of the Company and

Description of the Company and Basis of Financial Statement Presentation	12 Months Ended
	Dec. 31, 2016
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of the Company and Basis of Financial Statement Presentation	1. Description of the Company and Basis of Financial Statement Presentation Description of the Company Alliance HealthCare Services, Inc. and its subsidiaries (the “Company”) is a leading national provider of outsourced and joint venture healthcare services to hospitals and healthcare providers. The Company also operates freestanding outpatient radiology, oncology and interventional healthcare clinics and Ambulatory Surgical Centers that are not owned by hospitals or providers. Diagnostic imaging services are delivered through the Radiology Division (Alliance Radiology), radiation oncology services are delivered through the Oncology Division (Alliance Oncology), and interventional radiology and pain management services are delivered through the Interventional Division (Alliance Interventional). The Company is the nation’s largest provider of advanced diagnostic mobile imaging services, an industry-leading operator of fixed-site radiology centers, and a leading provider of stereotactic radiosurgery (“SRS”) nationwide. As of December 31, 2016, the Company operated 625 diagnostic imaging and radiation therapy systems, including 113 fixed-site imaging centers across the country and 33 radiation therapy centers and SRS facilities. With a strategy of partnering with hospitals, health systems and physician practices, the Company provides quality healthcare services for over 1,100 hospitals and healthcare partners in 46 states, where approximately 2,450 Alliance Team Members are committed to providing exceptional patient care and exceeding customer expectations. The Company was incorporated in the state of Delaware on May 27, 1987. Principles of Consolidation and Basis of Financial Statement Presentation The accompanying audited consolidated financial statements of the Company include the assets, liabilities, revenues and expenses of all subsidiaries over which the Company exercises control. Intercompany transactions have been eliminated. The Company evaluates participating rights in its assessment of control in determining consolidation of joint venture partnerships. The Company records noncontrolling interest related to its consolidated subsidiaries that are not wholly-owned. Investments in non-consolidated investees over which it exercises significant influence but does not control are accounted for under the equity method. The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“generally accepted accounting principles,” or “GAAP”).

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Cash and Cash Equivalents The Company classifies short-term investments with original maturities of three months or less as cash equivalents. Accounts Receivable The Company provides shared and single-user diagnostic imaging and oncology equipment and technical support services to the healthcare industry and directly to patients on an outpatient basis. Substantially all of the Company’s accounts receivable are due from hospitals, other healthcare providers and health insurance providers, including Medicare, located throughout the U.S. A substantial portion of the Company’s services are provided pursuant to long-term contracts with hospitals and other healthcare providers or directly to patients. Estimated credit losses are provided for in the consolidated financial statements. Concentration of Credit Risk Financial instruments which potentially subject the Company to a concentration of credit risk principally consist of cash, cash equivalents and accounts receivable. The Company invests available cash in cash equivalents and money market securities of high-credit-quality financial institutions. Cash and cash equivalents in excess of federally insured limits were $15.4 million and $29.5 million at December 31, 2016 and 2015, respectively. As of December 31, 2016 and 2015, the Company’s accounts receivable were primarily from clients in the healthcare industry and third-party payers. No individual customer represented more than 10% of the Company’s accounts receivable at December 31, 2016 and 2015. To reduce credit risk, the Company performs periodic credit evaluations of its clients, but does not generally require advance payments or collateral. Credit losses to clients in the healthcare industry have not been material. The provision for doubtful accounts was 0.4%, 0.6%, and 0.6% of revenues in 2016, 2015 and 2014, respectively. Plant, Property and Equipment The majority of the Company’s major medical equipment is stated at cost and is depreciated using the straight-line method over the initial estimated life to an estimated residual value, which is between 5% and 10% of original cost. If the Company continues to operate the equipment beyond its initial estimated life, the residual value is then depreciated to a nominal salvage value over 1 to 2 years. The estimated service lives for property and equipment are as follows: Estimated Useful Life Furniture and fixtures 5 to 10 years Office equipment 2 to 7 years Transportation and service equipment 2 to 10 years Major equipment 2 to 10 years Tenant improvements 5 to 25 years Buildings 7 years Routine maintenance and repairs are charged to expense as incurred. Major repairs and purchased software and hardware upgrades, which extend the life of or add value to the equipment, are capitalized and depreciated over the remaining useful life. Assets Under Capital Leases Assets under capital leases are recorded at the lower of the net present value of the minimum lease payments or the fair value of the leased asset at the inception of the lease. Amortization expense is recognized using the straight-line method over the shorter of the estimated useful life of the asset or the term of the related lease and is included in depreciation expense. Goodwill and Intangible Assets Accounting Standards Codification (“ASC”) 350, “Intangibles – Goodwill and Other,” requires that goodwill and indefinite-lived intangible assets are not amortized but instead tested for impairment at least annually at the reporting unit level. In addition, ASC 350 defines a reporting unit as an operating segment or one level below an operating segment (also known as a component). A component of an operating segment is a reporting unit under ASC 350 if the component constitutes a business for which discrete financial information is available and reviewed by management. The Company has evaluated ASC 350 and concluded there are three operating segments: Radiology, Oncology and Interventional. The Company has assessed that each component listed above meets the definition of a reporting unit based on the conclusions that each component constitutes a business, discrete financial information is available for each component, and management regularly reviews the results of such financial information. In accordance with ASC 350, the Company performs an annual impairment test in the fourth quarter for goodwill and indefinite-lived intangible assets or more frequently if an event occurs or circumstances change that would more-likely-than-not reduce the fair value of a reporting unit below its carrying amount. Such indicators include a sustained significant decline in the Company’s market capitalization or a significant decline in expected future cash flows due to changes in company-specific factors or the broader business climate. In evaluating goodwill for impairment, the Company first assesses qualitative factors to determine whether it is more-likely-than-not that the fair value of a reporting unit is less than its carrying amount. If the Company concludes that it is more-likely-than-not that the fair value of a reporting unit is less than its carrying amount, the Company conducts a two-step quantitative goodwill impairment test. First, for each reporting unit, the Company compares its estimated fair value with its net book value. If the estimated fair value exceeds its net book value, goodwill is deemed not to be impaired, and no further testing is necessary. If the estimated fair value does not exceed its net book value, the Company then performs a second test to calculate the amount of impairment, if any. To determine the amount of any impairment, the Company determines the implied fair value of goodwill. Specifically, the Company determines the fair value of all of the assets and liabilities of the reporting unit, including any unrecognized intangible assets, in a hypothetical calculation that yields the implied fair value of goodwill. If the implied fair value of goodwill is less than the recorded goodwill, the Company records an impairment charge for the difference. The impairment analysis in the first step utilizes two primary approaches to calculate the fair value of the reporting unit: the discounted cash flow (“DCF”) method and the Guideline Public Company (“GPC”) method. Under the DCF method, fair value is measured as the present worth of anticipated future net cash flows generated by a business. In a multi-period model, net cash flows attributable to a business are forecast for an appropriate period and then discounted to present value using an appropriate discount rate. In a single-period model, net cash flow or earnings for a normalized period are capitalized to reach a determination of present value. The methods, key assumptions, degree of uncertainty associated with the key assumptions and the potential events or changes in circumstances that could reasonably be expected to negatively affect the key assumptions with respect to the reporting unit are the estimated future net cash flows generated and the discount rate applied to capture the associated risks. The ability to achieve anticipated future net cash flows is subject to numerous assumptions and risks, including company-specific risks such as the ability to maintain and grow revenues, maintain or improve operating margins, control costs and anticipate working capital requirements. The anticipated future net cash flows are also dependent on industry-level factors, such as the impact of the Patient Protection and Affordable Care Act of 2010, on patient volumes and cost-reimbursement levels and continued availability of qualified doctors and other medical professionals who are necessary to staff the Company’s operations, among other potential impacts. Under the GPC method, value is estimated by comparing the subject company to similar companies with publicly-traded ownership interests. Guideline companies are selected based on comparability to the subject company, and valuation multiples are calculated and applied to subject company operating data. The key assumption used in connection with the GPC method focuses on identifying guideline companies that operate in the same (or similar) line of business as the reporting units with the same (or similar) operating characteristics. Eligible companies are selected based on Global Industry Classification Standard codes, Standard Industrial Classification codes, company descriptions, and industry affiliations. Considered factors include relative risk, profitability, and growth considerations of the reporting unit relative to the guideline companies. Value estimates for the reporting unit involve using multiples of market value of invested capital excluding cash to revenue and earnings before interest, income taxes, depreciation and amortization (“EBITDA”). Valuations derived using the GPC method rely on information primarily obtained from available industry market data and publicly available filings with the Securities and Exchange Commission (“SEC”). In testing indefinite-lived intangible assets for impairment, the Company first assesses qualitative factors to determine whether it is more-likely-than-not that the fair value of an indefinite-lived intangible asset is less than its carrying amount. If the Company concludes that it is more-likely-than-not that the fair value of an indefinite-lived intangible asset is less than its carrying amount, the Company conducts a two-step quantitative impairment test, which consist of a comparison of the fair value to its carrying amount. If the carrying amount exceeds its fair value, an impairment loss is recognized in an amount equal to that excess. ASC 350 also requires finite-lived intangible assets to be amortized over their respective estimated useful lives to their estimated residual values and reviewed for impairment in accordance with ASC 360, “Property, Plant, and Equipment.” For additional information, see Note 6. Impairment of Long-Lived Assets The Company accounts for long-lived assets in accordance with the provisions of ASC 360, which requires that long-lived assets be reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to undiscounted future net cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated undiscounted future cash flows, an impairment charge is recognized for the amount by which the carrying amount of the asset exceeds the fair value of the asset. Assets to be disposed of are reported at the lower of the carrying amount or fair value less costs to sell. Purchase Accounting In accordance with GAAP, the assets acquired and liabilities assumed in an acquired business are recorded at their estimated fair values on the date of acquisition. The difference between the purchase price amount and the net fair value of assets acquired and liabilities assumed is recognized as goodwill if it exceeds the estimated fair value and as a bargain purchase gain if it is below the estimated fair value. Determining the fair value of assets acquired and liabilities assumed requires management’s judgment, often utilizes independent valuation experts and involves the use of significant estimates and assumptions with respect to the timing and amounts of future cash inflows and outflows, discount rates, market prices and asset lives, among other items. The judgments made in the determination of the estimated fair value assigned to the assets acquired and liabilities assumed, as well as the estimated useful life of each asset and the duration of each liability, can materially impact the financial statements in periods after acquisition, such as through depreciation and amortization expense. Acquisitions of entities over which the Company exercises control have been recorded using the acquisition method of accounting and, accordingly, results of their operations have been included in the Company’s consolidated financial statements as of the effective date of each respective acquisition. Revenue Recognition The majority of the Company’s revenues are derived directly from healthcare providers and are primarily for radiology and oncology services. To a lesser extent, revenues are generated from direct billings to third-party payers or patients which are recorded net of contractual discounts and other arrangements for providing services at less than established patient billing rates. Revenues from billings to third-party payers and patients amounted to approximately 25%, 20% and 20% of revenues for the years ended December 31, 2016, 2015 and 2014, respectively. No single customer accounted for more than 10% of consolidated revenues in each of the years ended December 31, 2016, 2015 and 2014. The Company recognizes revenue in accordance with ASC 605, “Revenue.” As the price is pre-determined, all revenues are recognized at the time the delivery of service has occurred and collectability is reasonably assured which is based upon contract terms with healthcare providers and negotiated rates with third-party payers and patients. The Company also records revenue from management services that it performs based upon management service contracts with predetermined pricing. Revenues from these services amounted to approximately 0.5%, 2% and 2% of total revenue for the years ended December 31, 2016, 2015 and 2014, respectively. These revenues are recorded in the period in which the service is performed and collections of the billed amounts are reasonably assured in accordance with ASC 605. Share-based Payment Share-based compensation expense is based on the grant date fair value estimated in accordance with ASC 718, “Compensation—Stock Compensation.” This value is recognized ratably over the requisite service periods. The Company followed the alternative transition method as described in ASC 718 for computing its beginning additional paid-in capital pool. In addition, the Company treats the tax deductions from stock options as being realized when they reduce taxes payable in accordance with the principles and timing under the relevant tax law. The Company uses the Black-Scholes option pricing model to value the compensation expense associated with share-based payment awards. The fair value of each option award is estimated on the date of grant using the Black-Scholes option pricing model using certain assumptions (see Note 4). In addition, forfeitures are estimated when recognizing compensation expense and the estimate of forfeitures will be adjusted over the requisite service period to the extent that actual forfeitures differ, or are expected to differ, from such estimates. Changes in estimated forfeitures will be recognized through a cumulative catch-up adjustment in the period of change and will also impact the amount of compensation expense to be recognized in future periods. Derivatives The Company accounts for derivative instruments and hedging activities in accordance with the provisions of ASC 815, “Derivatives and Hedging.” On the date the Company enters into a derivative contract, management may designate the derivative as a hedge of the identified exposure. The Company formally documents all relationships between hedging instruments and hedged items, as well as the risk-management objective and strategy for undertaking various hedge transactions. In this documentation, the Company specifically identifies the firm commitment or forecasted transaction that has been designated as a hedged item and states how the hedging instrument is expected to hedge the risks related to the hedged item. The Company formally measures effectiveness of its hedging relationships, both at hedge inception and on an ongoing basis, in accordance with its risk management policy. The Company discontinues hedge accounting prospectively: (i) if it is determined that the derivative is no longer effective in offsetting the change in the cash flows of a hedged item; (ii) when the derivative expires or is sold, terminated or exercised; (iii) because it is probable that the forecasted transaction will not occur; (iv) because a hedged firm commitment no longer meets the definition of a firm commitment; or (v) if management determines that designation of the derivative as a hedge instrument is no longer appropriate. The Company’s derivatives are recorded on the balance sheet at fair value. For derivatives accounted for as cash flow hedges, any unrealized gains or losses on fair value are included in comprehensive income (loss), net of tax, assuming perfect effectiveness. Any ineffectiveness is recognized in earnings. Amounts recorded in comprehensive income (loss) are reclassified to earnings when the hedged item impacts earnings. Income Taxes The provision for income taxes is determined in accordance with ASC 740, “Income Taxes.” Deferred tax assets and liabilities are determined based on the temporary differences between the financial reporting and tax bases of assets and liabilities, applying enacted statutory tax rates in effect for the year in which the differences are expected to reverse. Future income tax benefits are recognized only to the extent that the realization of such benefits is considered to be more likely than not. The Company regularly reviews its deferred tax assets for recoverability and establishes a valuation allowance, when it is more likely than not that such deferred tax assets will not be recoverable, based on historical taxable income, projected future taxable income, and the expected timing of the reversals of existing temporary differences. Fair Values of Financial Instruments The Company uses the following methods and assumptions in estimating fair value disclosure for financial instruments: • Cash and cash equivalents The carrying amounts of cash and cash equivalents reported in the consolidated balance sheets approximate fair value due to the short-term maturity or variable rates of these instruments. • Debt Debt is recorded in the financial statements at historical cost. The carrying amounts of variable-rate borrowings at December 31, 2016 and 2015 approximate fair value estimates based on current market rates and credit spreads for similar debt instruments. • Contingent consideration Contingent consideration related to acquisitions at December 31, 2016 and 2015 is carried at fair value using probability-adjusted performance estimates . • Mandatorily redeemable noncontrolling interest The carrying amount of mandatorily redeemable noncontrolling interest related to the acquisition of PRC Associates, LLC (“PRC”) at December 31, 2016 and 2015 approximates fair value using the estimated implied fair value based on the Company’s ownership percentage . Further discussion of the mandatorily redeemable noncontrolling interest is disclosed in Note 3. • Derivative instruments Fair value was determined based on the income approach and standard valuation techniques to convert future amounts to a single present amount and approximates the net gains and losses that would have been realized if the contracts had been settled at each period-end. ASC 820, “Fair Value Measurement,” applies to all assets and liabilities that are being measured and reported at fair value on a recurring basis. ASC 820 requires disclosure that establishes a framework for measuring fair value by establishing a hierarchy for ranking the quality and reliability of the information used to determine fair values. The statement requires that assets and liabilities carried at fair value be classified and disclosed in one of the following three categories: Level 1 Quoted market prices in active markets for identical assets or liabilities; Level 2 Observable market-based inputs or unobservable inputs, including identical securities in inactive markets or similar securities in active markets that are corroborated by market data; or Level 3 Unobservable inputs that are not corroborated by market data. Self-Insurance The Company has purchased large deductible insurance policies for its workers’ compensation, auto liability, general liability, and professional liability exposures. The Company currently retains the first $250,000 of loss for workers’ compensation and auto liability and $100,000 for general and professional liability. The Company’s policy is to accrue amounts equal to the actuarially estimated costs to settle open claims of insureds, as well as an estimate of the cost of insured claims that have been incurred but not reported. The Company develops information about the size of the ultimate claims based on historical experience, current industry information and actuarial analysis, and evaluates the estimates for claim loss exposure on an annual basis. Assets and liabilities are reported in gross amounts in “Other assets” and “Other accrued liabilities” and “Other liabilities,” respectively. The Company believes that adequate provision has been made in the consolidated financial statements for these liabilities. The most significant assumptions used in the estimation process include determining the trend in costs, the expected cost of claims incurred but not reported and the expected costs to settle or pay damage awards with respect to unpaid claims. Recorded liabilities are based upon estimates, and while management believes that the estimates of loss are reasonable, the ultimate liability may be in excess of or less than the recorded amounts. Due to the inherent volatility of actuarially determined loss estimates, it is reasonably possible that the Company could experience changes in estimated losses that could be material to net income. If the Company’s actual liability exceeds its estimates of loss, its future earnings, cash flows and financial condition would be adversely affected. Advertising Costs The Company expenses all advertising costs as incurred. Advertising costs were $2.0 million, $1.3 million and $1.4 million for the years ended December 31, 2016, 2015 and 2014, respectively. Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Comprehensive Income (Loss) The Company reports comprehensive income (loss) in accordance with ASC 220, “Comprehensive Income.” For the years ended December 31, 2016, 2015 and 2014, the Company entered into multiple interest rate cap agreements and interest rate swap agreements, as discussed in Note 11. Assuming perfect effectiveness, any unrealized gains and losses related to the swaps and caps that qualify for cash flow hedge accounting are classified as a component of comprehensive income (loss), net of tax. Any ineffectiveness is recognized in earnings. Segment Reporting Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker (“CODM”) in deciding how to allocate resources and in assessing performance. In accordance with ASC 280, “Segment Reporting,” and based on the nature of the financial information that is received by the CODM, the Company operates in three reportable segments: Radiology, Oncology and Interventional. Each of these segments, on a stand-alone basis, provides and makes available its respective medical services in similar settings and operates within a singular regulatory environment. Further, management assesses the Company’s segment operations and each segment’s degree of efficiency and performance based on this structure of financial reporting and primarily makes operating decisions from these reportable segment results. All intercompany revenues, expenses, payables and receivables are eliminated in consolidation and are not reviewed when evaluating segment performance. Each segment’s performance is evaluated based on revenue and Adjusted EBITDA. There is no aggregation of operating segments in the Company’s determination of reportable segments. Prior to January 1, 2016, the Company operated in two reportable segments: Radiology and Oncology. The Interventional Division, the third operating segment, was formed in February of 2015 with the acquisition of The Pain Center of Arizona (“TPC”). In October of 2015 and in January of 2016, the Company acquired two pain practices in Florida, creating the current foundation of its Interventional segment. With the completion of its third acquisition, the Company began reporting Interventional services as a separate segment. The historical activity of the Interventional segment and Corporate / Other have been recast for consistent presentation for all periods presented. Net Income Per Share Basic net income per share is calculated b y dividing net income by the weighted average number of common shares outstanding during the year. Except where the result would be anti-dilutive, diluted net income per share is calculated by dividing net income by the sum of the weighted average number of common shares and potentially dilutive common shares outstanding during the period. Potentially dilutive common shares include dilutive outstanding stock options, unvested restricted stock and unvested restricted stock units (“RSUs”). Reclassifications Certain prior period amounts have been recast to reflect the effects from changes to the Company’s reportable segments and the adoption of recent accounting pronouncements (see Note 17 and “Recent Accounting Pronouncements below”). Recent Accounting Pronouncements Revenue Recognition In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, “Revenue from Contracts with Customers (Topic 606),” to clarify and converge the revenue recognition principles under GAAP and International Financial Reporting Standards and to develop guidance that would streamline and enhance revenue recognition requirements while also providing a more robust framework for addressing revenue issues. ASU 2014-09 outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry specific guidance. Key provisions of the ASU involve a 5-step model specific to recognizing revenue derived from customer contracts. In addition, ASU 2014-09 provides implementation guidance on several other important topics, including the accounting for certain revenue-related costs. The Company will be required to capitalize costs to acquire new contracts, whereas currently, the Company expenses those costs as incurred. In August 2015, the FASB issued an amendment to provide a one-year deferral of the effective date to annual reporting periods beginning on or after December 15, 2017. Early adoption of the standard as of December 15, 2016 (for interim and annual reporting periods beginning after that date) is permitted. The Company is currently working through an adoption plan, including identifying its revenue streams and completing a preliminary analysis of how it currently accounts for revenue transactions compared to the revenue accounting required under the new standard. The Company intends to complete its adoption plan in 2017. This plan includes a review of transactions supporting each revenue stream to determine the impact of accounting treatment under ASC 606 and the completion of a rollout plan for implementation of the new standard with affected functions in its organization. Because of the nature of the work that remains, at this time the Company is unable to reasonably estimate the impact of adoption on its consolidated financial statements. ASU 2014-09 will be effective for the Company beginning on January 1, 2018. Going Concern In August 2014, the FASB issued ASU 2014-15, “Presentation of Financial Statements—Going Concern (Subtopic 205-40).” Under GAAP, a going concern is presumed unless and until an entity’s liquidation becomes imminent. When an entity’s liquidation becomes imminent, financial statements should be prepared under the liquidation basis of accounting in accordance with Subtopic 205-30, “Presentation of Financial Statements—Liquidation Basis of Accounting.” However, there may be conditions or events that raise substantial doubt about an entity’s ability to continue as a going concern, even if liquidation is not imminent. In those situations, financial statements should continue to be prepared under the going concern basis of accounting. ASU 2014-15 provides guidance about management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to determine whether to disclose information about relevant conditions and events. ASU 2014-15 is effective for annual periods ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. The adoption of ASU 2014-15 for the year ended December 31, 2016 did not have a material impact on the Company’s consolidated financial statements. Simplifying the Presentation of Debt Issuance Costs In April 2015, the FASB issued ASU 2015-03, “Simplifying the Presentation of Debt Issuance Cost” that changes the presentation of debt issuance costs in financial statements. ASU 2015-03 requires entities to present such costs in the balance sheet as a direct reduction to the related debt liability rather than as a deferred cost (i.e., an asset) as required by prior guidance. In August 2015, the FASB issued clarifying authoritative guidance for debt issuance costs incurred in connection with line-of-credit arrangements. The guidance states that an entity should defer and present these debt issuance costs as an asset and subsequently amortize the deferred debt issuance costs ratably over the term of the line-of-credit arrangement. ASU 2015-03 does not change the recognition or measurement of debt issuance costs and is effective for fiscal years beginning after December 15, 2015. The guidance is required to be applied retrospectively to all prior periods presented. As of December 31, 2015, the Company had $6.6 million in deferred financing costs, net that was reclassified to offset long-term debt, net of current portion. Other than the revised balance sheet presentation and related disclosures, the adoption of the guidance on January 1, 2016 did not have a material impact on the Company’s consolidated financial statements. Balance Sheet Classification of Deferred Taxes In November 2015, the FASB issued ASU 2015-17, “Balance Sheet Classification of Deferred Taxes,” which requires entities to present deferred tax assets (“DTAs”) and deferred tax liabilities (“DTLs”) as noncurrent in a classified balance sheet. The ASU simplifies the current guidance, which requires entities to separately present DTAs and DTLs as current and noncurrent in a classified balance sheet. The adoption of ASU 2015-17 is effective for publicly traded business entities for annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. Early adoption is permitted. The Company elected to early-adopt this guidance and applied it retrospectively to periods presented in the consolidated financial statements. As of December 31, 2015, the Company had $6.5 million in DTAs that was reclassified to offset long-term DTLs. Other than the revised balance sheet presentation and related disclosures, the adoption of ASU 2015-17 on January 1, 2016 did not have a material impact on the Company’s consolidated financial statements. Leases In February 2016, the FASB issued ASU 2016-02, “Leases” (Topic 842), to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. The ASU supersedes the current guidance. The primary difference between current guidance and ASU 2015-02 is the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous GAAP. ASU 2016-02 also requires an entity to separate the lease components from the non-lease components (for example, maintenance services or other activities that transfer a good or service to the customer) in a contract. Only the lease components must be accounted for in accordance with this guidance. ASU 2016-02 is ef

Acquisitions and Transactions

Acquisitions and Transactions	12 Months Ended
	Dec. 31, 2016
Business Combinations Restructuring And Related Activities [Abstract]
Acquisitions and Transactions	3. Acquisitions and Transactions Tahoe Transaction On September 16, 2015, Tahoe Investment Group Co., Ltd. (“Tahoe”), formerly known as Fujian Thai Hot Investment Co., Ltd., agreed to purchase approximately 5,537,945 shares of the Company’s common stock from funds managed by Oaktree Capital Management, L.P. (“Oaktree”) and MTS Health Investors, LLC (“MTS”), and Larry C. Buckelew (together, The Tahoe Transaction closed on March 29, 2016. As a result of the Tahoe Transaction, Tahoe, through a wholly-owned subsidiary, owned an aggregate of approximately 52% of the Company’s outstanding shares of common stock as of December 31, 2016. The Company has not agreed to pay any management fees to Tahoe for any financial advisory services provided to the Company. On December 12, 2016, the Company announced it had received a letter describing a non-binding proposal from Tahoe to acquire all of the outstanding common shares of Alliance that are not currently owned by Tahoe for a purchase price of $9.60 per share in cash (the “Expression of Interest”). The Company’s board of directors authorized a Special Committee, comprised solely of directors not affiliated with Tahoe, to evaluate the Expression of Interest. The Expression of Interest indicated that any transaction with Tahoe would be subject to approval by the Special Committee and a non-waiveable condition requiring approval of a majority of the shares of Alliance not owned by Tahoe or is affiliates. Tahoe also indicated that the proposed transaction would not be subject to a financing condition . 2016 Acquisitions During the year ended December 31, 2016, a total of $25.9 million in cash was paid, net of cash acquired, for the acquisitions and the settlement of holdback liabilities. Transaction and other integration costs incurred in 2016 were $1.9 million and were included in “Transaction costs” in the Company’s consolidated statement of income and comprehensive income. These acquisitions contributed $8.7 million in revenues in 2016. The Company negotiated the respective purchase prices of the businesses based on the expected cash flows to be derived from their operations after integration into the Company’s existing operations. The acquisition purchase price for each business is allocated based on the fair values of the assets acquired and liabilities assumed, which are based on management estimates with the assistance of third-party appraisals. Purchase price allocations for the businesses acquired during 2016 are primarily based on provisional fair values and are subject to revision as the Company finalizes appraisals and other analyses. Final determination of the fair values may result in further adjustments to the values presented. North Alabama Cancer Care Organization (“NACCO”) Effective on November 1, 2016, the Company executed an agreement among its Oncology Division, the Healthcare Authority of the City of Huntsville, and the Center for Cancer Care to form a comprehensive cancer care partnership in northern Alabama. The Company contributed cash of $19.9 million and its rights to certain assets to NACCO in exchange for a 45.1% controlling interest in the joint venture. The Company financed this acquisition using the revolving loan facility. For additional information, see Note 9. The fair value of the consideration transferred was based on the net book value of the assets transferred by the Company to NACCO at the acquisition date because the Company had control of the assets before and after the transaction. Prior to the transfer, the Company wrote down a portion of the assets to fair value based on certain indicators of impairment. See Note 6 for details. The following table summarizes the consideration paid for NACCO and the recognized amounts of identifiable assets acquired and liabilities assumed at the acquisition date : (in thousands) Consideration: Cash consideration paid $ 19,854 Working capital 735 Certain intangible assets and equipment transferred to NACCO by the Company 9,900 Total consideration $ 30,489 Recognized amounts of NACCO assets acquired and liabilities assumed: Cash received $ 1,630 Equipment, net 1,334 Goodwill 14,116 Identifiable intangible assets 50,500 Noncontrolling interest (37,091 ) Total consideration $ 30,489 The values assigned to the various assets and liabilities acquired in this transaction are preliminary and may be subject to adjustment as the calculation of their respective fair values could be subject to change The goodwill resulting from the acquisition largely represents intangible assets that do not qualify for separate recognition, including existing patients and the solid record of patient care in the local community. A portion of the recorded goodwill and intangible assets is being amortized over 15 years for tax purposes. The following table summarizes the acquired intangible assets and their estimated useful lives at the acquisition date: (dollars in thousands) Estimated Useful Life (in years) Fair Value Identifiable intangible assets: Physician referral network 12 $ 26,500 Non-competition agreements 12 11,100 Trademarks 15 3,000 Certificates of need (“CONs”) N/A 9,900 $ 50,500 Acquired intangible assets are amortized on a straight-line basis over their estimated useful lives. The fair values of the identifiable intangible assets were estimated using several valuation methodologies, representing Level 3 fair value measurements. The value for physician referral network was estimated based on a multi-period excess earnings approach, whereas the values for non-competition agreements and trademarks were assessed using the with-and-without and relief from royalty methodologies, respectively. See Note 6 for discussion of CONs. Inputs used in the methodologies primarily included projected future cash flows, discounted at a rate commensurate with the risk involved. Specifically, key assumptions used in the valuation of the identifiable intangible assets, excluding CONs, consisted of the following: Discount rate 9.0 % Perpetual growth rate 1.0 % Tax rate 38.0 % Risk-free rate 4.0 % Peer company beta 0.69 The fair value of noncontrolling interest related to this transaction was estimated using a combination of the income approach, which analyzed projected discounted future cash flows, and the market approach, which considered comparable public companies as well as comparable industry transactions. Changes in these estimates or assumptions could materially affect the determination of fair value. Under the income and market approaches, the following Level 3 estimates and assumptions were used: Weighted Average Discount rate 16.3 % Perpetual growth rate 3.0 % Tax rate 39.2 % Risk-free rate 1.9 % EBITDA multiple 4.1x to 5.9x The results for the year ended December 31, 2016 included net revenue and net income before income taxes generated by NACCO of $4.0 million and $1.1 million, respectively. American Health Centers, Inc. In a two-part transaction on April 22, 2016 and May 19, 2016, the Company, through its Radiology Division, acquired the mobile business practice of American Health Centers, Inc. (“AHC”), a provider of fixed and mobile radiology and nuclear medicine services in New Hampshire and Vermont. The Company acquired 8 AHC mobile radiology sites, and 5 AHC mobile nuclear medicine sites. The combined cash purchase price, net of related contingent consideration, totaled $4.2 million. The Company financed this acquisition using the revolving loan facility. For additional information, see Note 9. The following table summarizes recognized amounts of identifiable assets acquired and liabilities assumed at the acquisition date: (in thousands) Equipment, net $ 2,354 Goodwill 335 Identifiable intangible assets 1,940 Total consideration $ 4,629 The goodwill resulting from the acquisition largely represents intangible assets that do not qualify for separate recognition, including existing patients and the solid record of patient care in the local community. A portion of the recorded goodwill and intangible assets is being amortized over 15 years for tax purposes. The Company recorded the intangible assets at fair value at the acquisition date, which was estimated using the income approach. Acquired intangible assets are amortized on a straight-line basis over their estimated useful lives. The following table summarizes the acquired intangible assets and their estimated useful lives at the acquisition date: (dollars in thousands) Estimated Useful Life (in years) Fair Value Identifiable intangible assets: Customer contracts 15 $ 1,600 Non-competition agreement 5 340 $ 1,940 The results for the year ended December 31, 2016 included net revenue and net income before income taxes generated by AHC of $2.5 million and $1.0 million, respectively. The values assigned to the various assets and liabilities acquired in this transaction are preliminary and may be subject to adjustment as the calculation of their respective fair values could be subject to change. The agreement includes contingent consideration arrangements, which are based on performance of the 18-month period following the transaction date. The fair value of these contingent consideration arrangements of $420,000 and $405,000 as of the acquisition date and December 31, 2016, respectively, was estimated using the Company’s established fair value approach. For additional information, see Note 5. 2015 Acquisitions During the year ended December 31, 2015, a total of $49.1 million in cash was paid, net of cash acquired, for the acquisitions and for the settlement of holdback liabilities. Transaction and other integration costs incurred in 2015 were $3.3 million and were included in “Transaction costs” in the Company’s consolidated statement of income and comprehensive income. These acquisitions contributed $43.8 million in revenues in 2015. Pacific Cancer Institute, Inc. On December 31, 2015, the Company through its Oncology Division, acquired a 95% controlling interest in the Pacific Cancer Institute (“PCI”), a state-of-the-art radiation therapy and SRS center located in Maui, Hawaii. The purchase price consisted of $11.0 million in cash, net of holdback liabilities. The Company financed this acquisition using the revolving loan facility. The following table summarizes recognized amounts of identifiable assets acquired and liabilities assumed at the acquisition date, as well as adjustments to finalize the valuations: (in thousands) Equipment, net $ 1,306 Other assets 152 Goodwill 6,505 Identifiable intangible assets 8,800 Deferred tax liability (3,748 ) Other liabilities (122 ) Noncontrolling interest (430 ) Total consideration $ 12,463 During the year ended December 31, 2016, the Company adjusted the PCI purchase price allocation as a result of obtaining additional information regarding the values of certain assets. The impact of the adjustment to the PCI purchase price allocation was a decrease to acquired equipment and an increase to goodwill of $615,000. The goodwill resulting from the acquisition largely represents other intangible assets that do not qualify for separate recognition, including existing patients and the solid record of patient care in the local community. (dollars in thousands) Estimated Useful Life (in years) Fair Value Identifiable intangible assets: CONs N/A $ 6,200 Physician referral network 10 1,000 Trademarks 15 950 Non-solicitation and non-competition agreements 5 650 $ 8,800 The fair value of noncontrolling interest related to this transaction was estimated to be $430,000 as of the acquisition date, using the income approach. For the year ended December 31, 2015, net revenue and net income generated by PCI were not material. The agreement includes contingent consideration arrangements, which are based on performance of the 12-month period following the transaction date. The fair value of these contingent consideration arrangements of $1.4 million was estimated using probability-adjusted performance estimates as of the acquisition date. As of December 31, 2016, the Company did not record a liability related to these contingent consideration arrangements since it believes that the achievement of the performance goals is unlikely. AHIP-Florida, LLC On October 14, 2015, the Company, through its Interventional Division, acquired a 60% controlling interest in PRC, a premier provider of interventional pain management healthcare with 8 locations in Central Florida and the Palm Coast. The purchase price consisted of $15.0 million in cash, net of $264,000 cash acquired. The Company financed this acquisition using the revolving loan facility The following table summarizes recognized amounts of identifiable assets acquired and liabilities assumed at the acquisition date, as well as adjustments to net a working capital settlement and finalize valuations: (in thousands) Cash received $ 264 Equipment, net 890 Other assets 351 Goodwill 8,234 Identifiable intangible assets 15,600 Other liabilities (475 ) Noncontrolling interest (5,921 ) Total consideration $ 18,943 During the year ended December 31, 2016, the Company received a working capital settlement of $387,000, which reduced total consideration. Additionally, the Company adjusted the PRC purchase price allocation as a result of obtaining additional information regarding the values of certain assets. The impact of the adjustment to the PRC purchase price allocation was a decrease to other assets of $833,000 and increases to goodwill, identifiable intangible assets and noncontrolling interest of $428,000, $200,000 and $182,000, respectively. The goodwill resulting from the acquisition largely represents other intangible assets that do not qualify for separate recognition, such as prominent leadership and solid record of patient care programs that set national standards for quality coordinated care in pain management. A portion of the recorded goodwill and intangible assets is being amortized over 15 years for tax purposes. The Company recorded the intangible assets at fair value at the acquisition date, which was estimated using the income approach. Acquired intangible assets are amortized on a straight-line basis over their estimated useful lives. The following table summarizes the acquired intangible assets and their estimated useful lives at the acquisition date: (dollars in thousands) Estimated Useful Life (in years) Fair Value Identifiable intangible assets: Physician referral network 20 $ 12,100 Trademarks 15 1,700 Non-solicitation and non-competition agreements 5 1,800 $ 15,600 The fair value of the mandatorily redeemable noncontrolling interest related to this transaction $2.4 million and $2.4 million as of the acquisition date and as of December 31, 2016, respectively. The agreement includes contingent consideration arrangements, which are based on performance of the 12-month period following the transaction date. The fair value of these contingent consideration arrangements of $2.5 million was estimated using probability-adjusted performance estimates as of the acquisition date. As of December 31, 2016, the Company had not made any payments and did not record a liability related to these contingent consideration arrangements since it believes that the achievement of performance goals was unlikely. Alliance-HNI, LLC and Subsidiaries On August 1, 2015, the Company obtained an additional 15.5% interest in its previously unconsolidated investment, Alliance-HNI, LLC (“AHNI”) through a step acquisition. Prior to August 1, 2015, the Company held a noncontrolling interest in AHNI, pursuant to its ownership of Medical Consultants Imaging, Co. (“MCIC”), which held a 50% interest in a joint venture that was subsequently renamed AHNI. Prior to the step acquisition on August 1, 2015, AHNI had three subsidiaries: Alliance-HNI Leasing Co. (“AHNIL”), Alliance-HNV PET/CT Services, LLC (“AHNVPS”) and Alliance-HNV PET/CT Leasing, LLC (“AHNVPL”). AHNI held a 98% interest in AHNIL, which AHNI consolidated, and, effectively, a 53.4% interest in AHNVPS, which AHNI did not consolidate. In addition to the Company’s original 50% investment in AHNI, it also had a 46.6% direct interest in AHNVPS prior to the step acquisition and, accordingly, the Company has historically consolidated AHNVPS and AHNVPL. On August 1, 2015, the Company contributed its 46.6% interest in HNVPS and its rights to certain assets to AHNI in exchange for an additional 15.5% interest in AHNI. After the transaction the Company holds a 65.5% interest in AHNI which, in turn, holds all of the outstanding interest in AHNVPS. As a result of gaining a controlling interest in AHNI, the Company began consolidating AHNI effective August 1, 2015. Pursuant to ASC 805, “Business Combinations,” the transaction is considered a step acquisition and the Company was required to remeasure its previously held equity interest in AHNI at its acquisition date fair value and recognize any resulting gain or loss. AHNVPS assets that the Company was in control of before and after the acquisition were maintained at their carrying amounts immediately before the acquisition date and no gain or loss or resulting goodwill was recognized on these assets. The following table summarizes the consideration paid for AHNI and the recognized amounts of the assets acquired and liabilities assumed at the acquisition date: (in thousands) Consideration: The Company’s equity investment in AHNVPS transferred to AHNI $ 721 Certain equipment transferred to AHNI by the Company 477 Fair value of total consideration transferred 1,198 Fair value of the Company’s equity interest held in AHNI before the business combination 13,645 Recognized amounts of AHNI assets acquired and liabilities assumed: Cash 1,848 Accounts receivable, net 2,064 Equipment, net 6,962 Intangible assets 13,700 Other assets 1,919 Long term debt (4,110 ) Other liabilities (1,095 ) Total recognized net assets 21,288 Noncontrolling interest in AHNI 9,463 Goodwill $ 2,988 The fair value of the consideration transferred was based on the net book value of the assets transferred by the Company to AHNI at the acquisition date because the Company had control of those assets before and after the transaction. The intangible assets consist primarily of physician referral network, trademarks, and CONs, a portion of which are being amortized over 15 years. The fair value of both the Company’s equity interest and the noncontrolling interest in AHNI, a private company, was estimated by applying the income approach and market approach. This fair value measurement was based on significant inputs that are not observable in the market and thus represents a fair value measurement categorized within Level 3 of the fair value hierarchy as described in Note 2 and Note 5. Key assumptions include a weighted average cost of capital of 11.5%, a revenue multiple of 1.7, and various earnings multiples between 5.0 and 6.5. The Company recognized a non-cash gain of $10.7 million as a result of remeasuring to fair value its 50% equity interest in AHNI held before the business combination. The gain is included in “Other income, net” in the accompanying consolidated statements of income and comprehensive income for the year ended December 31, 2015. The goodwill recorded largely represents other intangible assets that do not qualify for separate recognition, such as assembled workforce and well-known local presence and reputation. The results for the year ended December 31, 2015 included $10.6 million and $5.9 million of net revenue and net income before income taxes, respectively, generated by AHNI related to the post step acquisition period. The Pain Center of Arizona On February 17, 2015, the Company purchased approximately a 59% membership interest in TPC, a comprehensive full-time pain management medical practice with 12 locations within the state of Arizona. The purchase price consisted of $24.1 million in cash, net of $234,000 cash acquired, and net of extinguishment of $3.1 million of related party notes receivable. The Company financed this acquisition using the revolving loan facility. The following table summarizes recognized amounts of identifiable (in thousands) Cash received $ 234 Accounts receivable, net 4,440 Equipment, net 3,346 Other assets 416 Goodwill 22,566 Identifiable intangible assets 24,600 Debt (2,781 ) Other liabilities (3,030 ) Noncontrolling interest (20,598 ) Total consideration $ 29,193 The goodwill resulting from the acquisition largely represents other intangible assets that do not qualify for separate recognition, such as prominent leadership and solid record of patient care programs that set national standards for quality coordinated care in pain management . A portion of the recorded goodwill and intangible assets is being amortized over 15 years for tax purposes. The Company recorded the intangible assets at fair value at the acquisition date, which was estimated using the income approach. Acquired intangible assets are amortized on a straight-line basis over their estimated useful lives. The following table summarizes the acquired intangible assets and their estimated useful lives at the acquisition date: (dollars in thousands) Estimated Useful Life (in years) Fair Value Identifiable intangible assets: Physician referral network 20 $ 13,500 Trademarks 20 11,100 $ 24,600 The fair value of noncontrolling interest related to this transaction was estimated to be $20.6 million as of the acquisition date using the implied fair value based on the Company’s ownership percentage. The results for the year ended December 31, 2015 included $30.1 million of net revenue and $1.8 million of net income before income taxes, earnings from unconsolidated investees and noncontrolling interest generated by TPC. The agreement includes contingent consideration arrangements, which are based on performance of the 12-month period following the transaction date. The fair value of these contingent consideration arrangements of $1.8 million was estimated using probability-adjusted performance estimates as of the acquisition date. The Company paid $810,000 of the contingent consideration during the year ended December 31, 2016. 2014 Acquisition Charleston Area Radiation Therapy Centers In November 2014, the Company through its Oncology Division invested $14.4 million, net of cash received, to acquire 50% equity in the formation of a joint venture between Charleston Area Medical Center (“CAMC”) and Charleston Radiation Therapy Consultants, which established a new, state-of-the-art radiation therapy department at the CAMC Cancer Center that utilizes the latest in cancer technologies and treatments. In addition, Alliance has assumed full operational responsibility for the existing radiation oncology units at multiple locations in the Charleston, West Virginia area. As a result of the Company’s ability to consolidate the joint venture, it recorded goodwill of $6.9 million and intangible assets of $21.7 million, of which $11.5 million is attributed to the necessary CONs. The goodwill recorded largely represents other intangible assets that do not qualify for separate recognition, including existing patients of the hospital and the solid record of patient care that CAMC has established in the local community. The Company recognized revenues and net income before income taxes of $1.8 million and $899,000, respectively, in its 2014 consolidated statement of income and comprehensive income and believes the revenues and expenses attributed to CAMC are immaterial to its 2014 consolidated results of operations, financial position, or cash flows. Pro Forma Impact of Acquisitions The following table provides unaudited pro forma revenues and results of operations for the years ended December 31, 2016 and 2015, as if the acquisitions had occurred on January 1, 2015. The pro forma results were prepared from financial information obtained from the sellers of the businesses, as well as information obtained during the due diligence process associated with the acquisitions. The unaudited pro forma results reflect certain adjustments related to the acquisitions, such as increased depreciation and amortization expense resulting from the stepped-up basis to fair value of assets acquired and adjustments to reflect the Company’s borrowing and tax rates. The pro forma operating results do not include any anticipated synergies related to combining the businesses. Accordingly, such pro forma operating results were prepared for comparative purposes only and do not purport to be indicative of what would have occurred had the acquisitions been made as of January 1, 2015 or of results that may occur in the future. Year Ended December 31, (in thousands, except per share amounts) 2016 2015 2014 Total revenues $ 524,247 $ 522,347 $ 503,323 Net income attributable to the Company 3,547 13,703 16,773 Basic earnings per share 0.33 1.28 1.57 Diluted earnings per share 0.32 1.26 1.55 Restructuring Plan From time to time, the Company’s management implements immaterial restructuring plans, including the closure or consolidation of certain sites as a result of the loss of certain customers. The impact of the charges resulting from restructuring plans are summarized below: Year Ended December 31, (in thousands) 2016 2015 2014 Cost of revenues, excluding depreciation and amortization $ 787 $ 900 $ 1,440 Selling, general and administrative expenses 275 175 1,162 Severance and related costs — 27 — Amortization expense — 225 — Other expense, net 573 — — Total restructuring charges $ 1,635 $ 1,327 $ 2,602 The restructuring plans, under which costs were incurred during the year ended December 31, 2016, were adopted at varying times, beginning in 2009, and are expected to be completed by the third quarter of 2019.

Share-Based Payment

Share-Based Payment	12 Months Ended
	Dec. 31, 2016
Share Based Compensation [Abstract]
Share-Based Payment	4. Share-based Payment In November 1999, the Company adopted an employee stock option plan (as amended and restated, the “1999 Equity Plan”) pursuant to which options and awards with respect to a total of 3,005,000 shares have become available for grant. As of December 31, 2016, a total of 948,886 shares remained available for grant under the 1999 Equity Plan. Stock Options Options are granted with exercise prices equal to the fair value of the Company’s common stock at the date of grant. All options have 10-year terms. Options granted after January 1, 2008 are typically time-based and vest in equal tranches over 3 or 4 years. During the year ended December 31, 2016, the vesting for 71,057 options was accelerated due to a change in control in conjunction with the closing of the Tahoe Transaction (see Note 3). During the years ended December 31, 2015 and 2014, there were no options for which vesting was accelerated. The following weighted average assumptions were used in the estimated grant date fair value calculations for stock option awards: Year Ended December 31, 2016 2015 2014 Risk free interest rate 1.53 % 1.65 % 1.83 % Expected dividend yield — % — % — % Expected stock price volatility 66.5 % 65.2 % 66.3 % Average expected life (in years) 6.0 6.0 6.0 Weighted average grant date fair value $ 4.32 $ 14.25 $ 17.56 The following table summarizes the Company’s stock option activity: (dollars in thousands except per share amounts) Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (1) Outstanding at December 31, 2015 646,290 $ 19.91 Granted 200,388 $ 7.16 Exercised (121,667 ) $ 5.05 Canceled/forfeited (74,042 ) $ 22.08 Outstanding at December 31, 2016 650,969 $ 18.51 6.4 $ 917 Vested and expected to vest in the future at December 31, 2016 612,122 $ 19.23 6.2 $ 823 Vested and exercisable at December 31, 2016 463,165 $ 23.11 5.2 $ 462 (1) Represents the difference between the exercise price and the value of the Company’s stock at fiscal year-end. The aggregate intrinsic value of stock options exercised during the years ended December 2016, 2015 and 2014 was $1.4 million, $25,000 and $1.6 million, respectively. The following table summarizes information of the stock options outstanding and exercisable at December 31, 2016: Stock Options Outstanding Stock Options Exercisable Exercise Price Range Number of Shares Weighted Average Exercise Price Remaining Contractual Term (in years) Number of Shares Weighted Average Exercise Price Remaining Contractual Term (in years) $5.70 — $6.29 127,002 $ 5.96 5.0 127,002 $ 5.96 5.0 $6.30 — $6.93 145,804 $ 6.93 9.2 — $ — — $6.94 — $22.43 67,287 $ 9.79 8.1 25,287 $ 12.70 6.4 $22.44 — $28.46 67,609 $ 24.01 8.1 67,609 $ 24.01 8.1 $28.47 — $28.92 58,815 $ 28.61 4.6 58,815 $ 28.61 4.6 $28.93 — $30.27 102,952 $ 29.14 6.7 102,952 $ 29.14 6.7 $30.28 — $46.30 81,500 $ 40.72 1.3 81,500 $ 40.72 1.3 $5.70 — $46.30 650,969 $ 18.52 6.4 463,165 $ 23.11 5.2 The following table summarizes the Company’s unvested stock option activity: (dollars in thousands except per share amounts) Number of Shares Weighted Average Grant Date Fair Value Aggregate Unrecognized Compensation (1) Weighted Average Period Over Which Expected to be Recognized (in years) Unvested at December 31, 2015 158,671 $ 15.01 Granted 200,388 $ 4.32 Vested (156,171 ) $ 15.05 Forfeited (15,084 ) $ 5.60 Unvested at December 31, 2016 187,804 $ 4.33 $ 476 2.2 (1) The valuation model applied in this calculation utilizes highly subjective assumptions that could potentially change over time, including the expected forfeiture rate and performance targets. Therefore, the amount of unrecognized share-based payment noted above does not necessarily represent the value that will ultimately be realized by the Company in the consolidated statements of income and comprehensive income. The total fair value of stock options vested during the years ended December 2016, 2015 and 2014 was $2.3 million, $1.1 million and $837,000, respectively. Stock Awards The 1999 Equity Plan permits the award of restricted stock, RSUs, stock bonus awards and performance-based stock awards (collectively referred to as “stock awards”). In the third quarter of 2014, 25,000 RSUs, which vest based upon achieving certain market performance conditions, were granted to executive management. Specifically, the Company’s closing stock price per common share must equal or exceed a value of $40.00 per share for 10 consecutive days between the dates of January 1, 2015 and April 21, 2017. If these conditions are not achieved before April 21, 2017, these RSUs will expire. In accordance with ASC 718, expense related to RSUs that vest based on achieving a market condition should not be recognized until the derived vesting period has been met, and at such time the derived vesting period becomes the requisite service period. These RSUs contain provisions that vesting may be accelerated under a change in control of the Company. The RSU award agreement provided that in the event of a change in control, the unvested portion of the award will convert into the right to receive a cash amount (the “Cash Right”) equal to the number of unvested restricted stock units multiplied by the per share consideration received by the holders of the Company’s common stock in the change in control and the Cash Right shall vest on the six-month anniversary of the consummation of the change in control subject to the executive’s continued service through such date; provided, that in the event the executive is terminated without “cause” or for “good reason” (each as defined in the executive’s employment agreement) the Cash Right shall vest in full on the date of such termination (the “Cash Right Conversion”). The Tahoe Transaction constituted a change in control under the terms of the RSU award agreement and for purposes of the Cash Right Conversion, the special committee of the board of directors approved that the per share consideration received by the holders of the Company’s common stock upon the consummation of the Tahoe Transaction was $18.50 per share. The monetary value of the Cash Right of $463,000 was paid during the year ended December 31, 2016. For additional information on the Tahoe Transaction, see Note 3. The following table summarizes the Company’s RSU activity: (dollars in thousands except per share amounts) Shares Weighted Average Grant Date Fair Value Aggregate Unrecognized Compensation Weighted Average Period Over Which Expected to be Recognized (in years) Unvested at December 31, 2015 74,413 9.18 Granted 175,441 8.30 Vested (74,413 ) 9.18 Forfeited (7,588 ) 6.93 Unvested at December 31, 2016 167,853 $ 8.37 $ 1,182 1.3 The total fair value of RSUs vested during the years ended December 2016, 2015 and 2014 was $683,000, $692,000 and $337,000, respectively. Share-based Compensation Expense The impact of recording share-based compensation expense in the consolidated statements of income and comprehensive income is summarized below: Year Ended December 31, (in thousands) 2016 (1) 2015 2014 Share-based compensation expense (2) $ 3,176 $ 1,701 $ 1,515 Income tax benefit (936 ) (595 ) (540 ) Total share-based compensation expense after income taxes $ 2,240 $ 1,106 $ 975 (1) Includes Cash Right of $463. (2) Included in “Selling, general and administrative expenses” in the Company’s consolidated statement of income and comprehensive income.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	5. Fair Value of Financial Instruments Instruments Measured at Fair Value on a Recurring Basis The following table summarizes the valuation of the Company’s financial instruments that are reported at fair value on a recurring basis: Fair Value as of December 31, 2016 Fair Value as of December 31, 2015 (in thousands) Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Financial assets: Interest rate contracts - asset position $ 55 $ — $ 55 $ — $ — $ — $ — $ — Total financial assets $ 55 $ — $ 55 $ — $ — $ — $ — $ — Financial liabilities: Contingent consideration related to acquisitions $ 555 $ — $ — $ 555 $ 5,750 $ — $ — $ 5,750 Mandatorily redeemable noncontrolling interest 2,386 — — 2,386 2,386 — — 2,386 Interest rate contracts - liability position 53 — 53 — 86 — 86 — Total financial liabilities $ 2,994 $ — $ 53 $ 2,941 $ 8,222 $ — $ 86 $ 8,136 The Company’s derivative instruments are primarily pay-fixed, receive-variable interest rate swaps and caps based on the London interbank offered rate (“LIBOR”) swap rate. The Company has elected to use the income approach to value these derivatives, using observable Level 2 market expectations at measurement date and standard valuation techniques to convert future amounts to a single present amount assuming that participants are motivated but not compelled to transact. Level 2 inputs for interest rate swap and cap valuations are limited to quoted prices for similar assets or liabilities in active markets (specifically futures contracts on LIBOR for the first two years) and inputs other than quoted prices that are observable for the asset or liability (specifically LIBOR cash and swap rates at commonly quoted intervals and implied volatilities for options). According to ASC 820, the fair value measurement of an asset or liability must reflect the nonperformance risk of the entity and the counterparty. Therefore, the impact of the counterparty’s creditworthiness and the Company’s creditworthiness has also been factored into the fair value measurement of the derivative instruments. For additional information, see Note 11. The fair value of the liability for contingent consideration related to acquisitions was estimated using probability-adjusted performance estimates (Level 3 inputs) over the performance periods following the transaction dates (see Note 3). These estimates represent inputs for which market data are not available and are developed using the best information available about the assumptions that market participants would use when pricing the liability. Significant increases or decreases to either of these inputs in isolation would result in a significantly higher or lower liability. Ultimately, the liability will be equivalent to the amount paid, and the difference between the fair value estimate and amount paid will be recorded in earnings. Changes in the fair value of the Company’s Level 3 liabilities were as follows: (in thousands) Contingent consideration related to acquisitions Mandatorily redeemable noncontrolling interest Balance at December 31, 2014 $ — $ — Additions (1) 5,750 2,386 Balance at December 31, 2015 5,750 2,386 Additions (1) 420 — Settlement of contingent consideration related to acquisitions (825 ) — Fair value adjustment (2) (4,790 ) — Balance at December 31, 2016 $ 555 $ 2,386 (1) See Note 3. (2) Adjustments to the estimated fair value of the contingent consideration are related to the actual versus expected performance of acquisitions and are included in “Other income, net” in the Company’s consolidated statement of income and comprehensive income. Financial instruments measured and recorded at fair value on a recurring basis were presented on the Company’s consolidated balance sheets as follows: Fair Value as of December 31, 2016 Fair Value as of December 31, 2015 (in thousands) Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Financial assets: Other assets $ 55 $ — $ 55 $ — $ — $ — $ — $ — Total financial assets $ 55 $ — $ 55 $ — $ — $ — $ — $ — Financial liabilities: Other accrued liabilities $ 2,994 $ — $ 53 $ 2,941 $ 8,139 $ — $ 3 $ 8,136 Other liabilities — — — — 83 — 83 — Total financial liabilities $ 2,994 $ — $ 53 $ 2,941 $ 8,222 $ — $ 86 $ 8,136 None of the Company’s instruments has transferred from one level to another. Instruments Not Recorded at Fair Value on a Recurring Basis The following table summarizes the fair values and book values of the Company’s long-term debt: December 31, 2016 December 31, 2015 (in thousands) Fair Value Book Value Fair Value Book Value Variable-rate debt $ 526,475 $ 533,939 $ 538,520 $ 537,018 Fixed-rate debt 41,572 39,308 40,262 40,667 $ 568,047 $ 573,247 $ 578,782 $ 577,685 The fair value of the Company’s long-term debt is estimated using Level 2 inputs based on quoted market prices or pricing models using current market rates. Assets and Liabilities Recorded at Fair Value on a Non-Recurring Basis The Company also measures the fair value of certain assets on a non-recurring basis (utilizing Level 3 inputs), generally on an annual basis, in connection with acquisitions, or when events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. These assets include goodwill, intangible assets, long-lived assets and investments in unconsolidated investees. See Notes 3, 6 and 7 for details.

Impairment Charges

Impairment Charges	12 Months Ended
	Dec. 31, 2016
Goodwill And Intangible Assets Disclosure [Abstract]
Impairment Charges	6. Impairment Charges For the year ended December 31, 2016, the Company performed its annual impairment test in the fourth quarter for goodwill and indefinite-lived intangible assets. See Note 7 for details. In 2016, in accordance with ASC 350, the Company performed an interim impairment test due to a deterioration in operating results related to an Oncology site location in Alabama. The Company revalued the indefinite-lived intangible asset specifically related to the single location and recorded a non-cash charge of $882,000, which is included in “Impairment charges” in the consolidated statements of income and comprehensive income. In calculating fair value, the Company gave equal weight to the income approach, which analyzed projected discounted cash flows, and the market approach, which considered comparable industry transactions. Changes in these estimates or assumptions could materially affect the determination of fair value. Under the income and market approaches, the following Level 3 estimates and assumptions were used: Discount rate 16.0% Perpetual growth rate 3.0% Tax rate 39.2% Risk-free rate 2.0% EBITDA multiple 4.0x to 6.0x During 2015, the Company closed a radiation therapy center and, as a result, recorded a non-cash charge to write off $6.7 million of intangible assets not subject to amortization associated with that center in its Oncology Division. The revenues from the radiation therapy center were not material for the year ended December 31, 2015. Additionally, impairment charges totaling $308,000 were recorded in 2014 primarily due to the write-off of the Company’s equity investment in an Oncology site location upon the site’s closure in 2014.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2016
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	7. Goodwill and Intangible Assets Goodwill Changes in the carrying amount of goodwill are as follows: (in thousands) Radiology Oncology Interventional Total Balance at December 31, 2014 $ 42,166 $ 21,698 $ — $ 63,864 Goodwill acquired during the period 2,656 5,891 30,371 38,918 Balance at December 31, 2015 44,822 27,589 30,371 102,782 Goodwill acquired during the period 335 14,116 854 15,305 Adjustments to goodwill during the period — 615 428 1,043 Balance at December 31, 2016 $ 45,157 $ 42,320 $ 31,653 $ 119,130 Gross goodwill $ 199,499 $ 62,222 $ 31,653 $ 293,374 Accumulated impairment charges (154,342 ) (19,902 ) — (174,244 ) Balance at December 31, 2016 $ 45,157 $ 42,320 $ 31,653 $ 119,130 As discussed in Note 1, the Company tests its goodwill and indefinite-lived intangible assets annually or more frequently depending on certain impairment indicators. There were no interim impairment tests performed. Goodwill was tested for impairment at the reporting unit level as of October 1, 2016 and October 1, 2015, the dates of the Company’s annual impairment review for the years ended December 31, 2016 and 2015, respectively. The Company made a qualitative assessment of whether goodwill impairment exists. Based on negative industry trends and a decline in the Company’s stock price, the Company performed the first step of the impairment test. In estimating fair values, the Company gave equal weight to an income approach (the DCF method) and a market approach (the GPC method). See Note 2 for details. Specifically, the Company utilized the following Level 3 estimates and assumptions in its analyses: October 1, 2016 October 1, 2015 Discount rate 10.0% to 13.0% 10.0% to 15.0% Perpetual growth rate 1.0% to 3.0% 2.5% Tax rate 40.0% 40.0% Risk-free rate 4.0% 2.5% Peer company beta 0.5 to 0.6 0.8 to 1.2 Revenue multiple 1.0x to 1.35x 1.0x to 1.5x EBITDA multiple 5.5x 5.5x to 6.0x In both 2016 and 2015, the respective annual impairment tests yielded individual fair values for each reporting unit that exceeded their respective carrying values; therefore, the reporting units were not considered at risk of impairment. The estimated fair value at October 1, 2016 exceeded carrying value by 103%, 6% and 8% for the Radiology, Oncology and Interventional reporting units, respectively. Changes in these estimates or assumptions could materially affect the determination of fair value and the conclusions of the first step of the Company’s impairment test. In addition to its annual review, the Company performs a test of impairment when indicators of impairment are present. As of December 31, 2016 and 2015, there were no indications of impairment of the Company’s goodwill balances. Intangible Assets Intangible assets consisted of the following: December 31, 2016 December 31, 2015 (dollars in thousands) Weighted Average Useful Life (in years) Gross Carrying Amount Accumulated Amortization Intangible Assets, net Gross Carrying Amount Accumulated Amortization Intangible Assets, net Finite-lived intangible assets: Customer contracts 16 $ 230,323 $ (101,240 ) $ 129,083 $ 186,316 $ (92,280 ) $ 94,036 Other 18 41,820 (22,141 ) 19,679 38,522 (20,540 ) 17,982 Total amortizing intangible assets 16 $ 272,143 $ (123,381 ) $ 148,762 $ 224,838 $ (112,820 ) $ 112,018 Indefinite-lived intangible assets 50,215 50,905 Total other intangible assets $ 198,977 $ 162,923 Indefinite-lived intangible assets, which consist of CONs and regulatory authority rights, were tested for impairment as of October 1, 2016 and October 1, 2015, the dates of the Company’s annual impairment review for the years ended December 31, 2016 and 2015, respectively. The Company elected to perform a qualitative assessment of factors to determine whether further impairment testing was required. Based on its testing, the Company concluded there was no impairment of indefinite-lived intangible assets as of October 1, 2016 and October 1, 2015. In addition to its annual review, the Company performs an impairment test when indicators of impairment are present. As of December 31, 2016 and 2015, there were no indications of impairment of the Company’s indefinite-lived intangible assets balances. Amortization expense for finite-lived intangible assets is reported as “Amortization expense” in the consolidated statements of income and comprehensive income. Estimated annual amortization expense for each of the fiscal years ending December 31, is presented below: (in thousands) 2017 $ 13,062 2018 12,689 2019 12,200 2020 11,710 2021 10,802 Thereafter 88,299 Total expected amortization expense $ 148,762

Supplemental Balance Sheet Info

Supplemental Balance Sheet Information	12 Months Ended
	Dec. 31, 2016
Supplemental Balance Sheet Information [Abstract]
Supplemental Balance Sheet Information	8. Supplemental Balance Sheet Information Plant, property and equipment, net as of December 31, 2016 are as follows: (in thousands) Cost Accumulated Depreciation Net Carrying Amount Furniture and fixtures $ 4,905 $ (4,231 ) $ 674 Office equipment 80,384 (57,295 ) 23,089 Transportation and service equipment 16,140 (4,291 ) 11,849 Major equipment 794,153 (639,452 ) 154,701 Tenant improvements 43,888 (29,665 ) 14,223 Buildings and land 340 (62 ) 278 Total $ 939,810 $ (734,996 ) $ 204,814 Included in major equipment and transportation and service equipment as of December 31, 2016 are assets held under capital leases with a cost of $24.9 million and $2.8 million, respectively, and accumulated depreciation of $9.4 million and $209,000, respectively. Plant, property and equipment, net as of December 31, 2015 are as follows: (in thousands) Cost Accumulated Depreciation Net Carrying Amount Furniture and fixtures $ 4,825 $ (3,977 ) $ 848 Office equipment 71,245 (49,981 ) 21,264 Transportation and service equipment 5,884 (3,306 ) 2,578 Major equipment 758,718 (623,429 ) 135,289 Tenant improvements 42,792 (25,904 ) 16,888 Buildings and land 340 (19 ) 321 Total $ 883,804 $ (706,616 ) $ 177,188 Included in major equipment as of December 31, 2015 are assets held under capital leases with a cost of $19.3 million and accumulated depreciation of $7.0 million. Other accrued liabilities consisted of the following: (in thousands) December 31, 2016 December 31, 2015 Systems rental and maintenance costs $ 1,064 $ 1,808 Site rental fees 899 1,121 Property and sales taxes payable 7,254 8,695 Self-insurance expense 2,612 2,037 Legal fees 1,537 1,971 Deferred gain on sale of equipment 87 312 Equipment purchases 848 4,756 Customer overpayments 2,555 1,580 Contingent consideration related to acquisition 555 5,750 Mandatorily redeemable noncontrolling interest 2,386 2,386 Other expenses 9,526 6,037 Total $ 29,323 $ 36,453

Long-Term Debt and Senior Subor

Long-Term Debt and Senior Subordinated Credit Facility	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Long-Term Debt and Senior Subordinated Credit Facility	9. Long-Term Debt and Senior Subordinated Credit Facility Long-term debt consisted of the following: (in thousands) December 31, 2016 December 31, 2015 Term loan facility $ 497,674 $ 502,874 Discount on term loan facility (1,310 ) (1,823 ) Revolving loan facility 21,500 19,500 Equipment under capital leases 16,040 13,006 Equipment debt 39,343 44,128 Deferred financing costs, net (24,502 ) (6,594 ) Long-term debt, including current portion 548,745 571,091 Less current portion 20,652 20,406 Long-term debt $ 528,093 $ 550,685 Equipment debt, collateralized by equipment, have interest rates ranging from 1.94% to 9.00% and are payable in various monthly principal and interest payments through 2021. Equipment under capital leases, collateralized by equipment, have interest rates ranging from 2.68% to 5.98% and are payable in various monthly principal and interest payments through 2021. Credit Facility and Senior Secured Term Loan Refinancing On June 3, 2013, the Company replaced its existing credit facility with a new senior secured credit agreement with Credit Suisse AG, Cayman Islands Branch, as administrative agent, and the other lenders party thereto (the “Credit Agreement”). The Credit Agreement consists of (i) a $340.0 million, six-year term loan facility, (ii) a $50.0 million, five-year revolving loan facility, including a $20.0 million sublimit for letters of credit, (iii) uncommitted incremental loan facilities of $100.0 million of revolving or term loans, plus an additional amount if the Company’s pro forma leverage ratio is less than or equal to 3.25, subject to receipt of lender commitments and satisfaction of specified conditions, and (iv) a $80.0 million delayed draw term loan facility, which was required to be drawn within thirty days of June 3, 2013 and used for the redemption of the Company’s $190.0 million of 8% Senior Notes (“Notes”). On July 3, 2013 the delayed draw term loan facility was utilized, of which the proceeds were used to redeem $80.0 million in aggregate principal amount of the Company’s outstanding Notes. The delayed draw term loan facility converted into, and matched the terms of, the new $340.0 million term loan facility. Borrowings under the Credit Agreement bear interest through maturity at a variable rate based upon, at the Company’s option, either the LIBOR or the base rate (which is the highest of the administrative agent’s prime rate, one-half of 1.00% in excess of the overnight federal funds rate, and 1.00% in excess of the one-month LIBOR rate), plus, in each case, an applicable margin. With respect to the term loan facility, the applicable margin for LIBOR loans is 3.25% per annum, and with respect to the revolving loan facility, the applicable margin for LIBOR loans ranges from 3.00% to 3.25% per annum, based on the applicable leverage ratio, and in each case, with a LIBOR floor of 1.00%. The applicable margin for base rate loans under the term loan facility is 2.25% per annum and under the revolving loan facility ranges from 2.00% to 2.25% per annum, based on the applicable leverage ratio. Prior to the refinancing of the term loan facility, the applicable margin for base rate loans was 4.25% per annum and the applicable margin for revolving loans was 5.25% per annum, with a LIBOR floor of 2.00%. The Company is required to pay a commitment fee which ranges from 0.38% to 0.50% per annum, based on the applicable leverage ratio, on the undrawn portion available under the revolving loan facility and variable per annum fees with respect to outstanding letters of credit. Obligations under the Credit Agreement are guaranteed by substantially all the Company’s direct and indirect domestic subsidiaries. The obligations under the Credit Agreement and the guarantees are secured by a lien on substantially all tangible and intangible property and by a pledge of all of the shares of stock and limited liability company interests of the Company’s direct and indirect domestic subsidiaries, of which the Company now owns or later acquires more than a 50% interest, subject to limited exceptions. In addition to other covenants, the Credit Agreement places limits on the ability of the Company and its subsidiaries to declare dividends or redeem or repurchase capital stock, prepay, redeem or purchase debt, incur liens and engage in sale-leaseback transactions, make loans and investments, incur additional indebtedness, amend or otherwise alter debt and other material agreements, engage in mergers, acquisitions and asset sales, transact with affiliates and alter the business conducted by the Company and its subsidiaries. The Credit Agreement also contains a leverage ratio covenant requiring the Company to maintain a maximum ratio of consolidated total debt to Consolidated Adjusted EBITDA expense that ranges from 4.95 to 1.00 to 4.30 to 1.00. At December 31, 2016, the Credit Agreement requires a maximum leverage ratio of not more than 4.55 to 1.00. Failure to comply with the covenants in the Credit Agreement could permit the lenders under the Credit Agreement to declare all amounts borrowed under the Credit Agreement, together with accrued interest and fees, to be immediately due and payable, and to terminate all commitments under the Credit Agreement. Amendments to the Credit Agreement On October 11, 2013, the Company entered into an amendment to the Credit Agreement with Credit Suisse AG, Cayman Islands Branch, as administrative agent, and the other lenders party thereto (the “First Amendment”). Pursuant to the First Amendment, the Company raised $70.0 million On June 19, 2015, the Company entered into a second amendment to the Credit Agreement with Credit Suisse AG, Cayman Islands Branch, as administrative agent, and the other lenders party thereto (the “Second Amendment”). Pursuant to the Second Amendment, the Company raised the remaining $30.0 million in incremental term loan commitments. The funds were used to repay all outstanding borrowings under the Company’s revolving loan facility, pay fees and expenses related to the Second Amendment, and general corporate purposes. The Second Amendment did not impact the borrowing capacity on the revolving loan facility which remains at $50.0 million. The incremental term loan under the Second Amendment was funded at 99.5% of principal amount and will mature on the same date as the existing term loan under the Company’s Credit Agreement on June 3, 2019. Upon funding, the incremental term loans were converted to match all the terms of existing term loans. Interest on the incremental term loan is calculated, at the Company’s option, at a base rate plus a 2.25% margin or LIBOR plus a 3.25% margin, subject to a 1.00% LIBOR floor. The quarterly amortization payments of all term loans under the credit facility for the first five and one-half years was initially established at $1.1 million. The quarterly amortization payment was increased to $1.3 million in June 2015 pursuant to the Second Amendment. The Company is also required to make mandatory prepayments of term loans under the Credit Agreement, subject to specified exceptions, from excess cash flow (as defined in the Credit Agreement) and with the proceeds of asset sales, debt issuances and specified other events. On March 29, 2016, the Company entered into a third amendment to the Credit Agreement, in connection with the Tahoe Transaction, with Credit Suisse AG, Cayman Islands Branch, as administrative agent, and the other lenders party thereto (the “Third Amendment”). Pursuant to the Third Amendment, (i) the defined term “Investors” was amended to include THAIHOT Investment Company Limited, a subsidiary of Tahoe, so that the sale by the Selling Stockholders would not be deemed to constitute a change of control and (ii) the soft call provision was reinstated to commence on the date the Third Amendment is effective and end the date that is twelve months after such commencement. In connection with the Third Amendment, the Company incurred fees totaling $25.0 million, which were capitalized and amortized using the effective interest method as interest expense over the term of the Credit Agreement. These fees were paid by both the buyer and sellers in the Tahoe Transaction. Under the soft call provision, if the Company makes a voluntary prepayment of any Term Loan or prepays, refinances, substitutes or replaces any Term Loan, and such action results in a reduction in the effective interest cost or weighted average yield of the Term Loan, then the Company shall pay to the administrative agent, for the ratable account of each of the lenders holding Term Loans a prepayment premium equal to 1.0% of the aggregate principal amount of the Term Loans so prepaid, refinanced, substituted or replaced. As of December 31, 2016, the Company’s ratio of consolidated total debt to Consolidated Adjusted EBITDA calculated pursuant to the Credit Agreement was 4.03 to 1.00. As of December 31, 2016, the Company had $24.1 million of available borrowings under our revolving loan facility, net of $21.5 million outstanding on the revolving loan facility and $4.4 million outstanding in letters of credit. Notes Payable and Line of Credit with PNC As a result of the step acquisition on August 1, 2015, and subsequent consolidation of AHNI described in Note 3, the Company had notes payable to PNC Equipment Finance, LLC (“PNC”) totaling $8.6 million at December 31, 2016. The notes payable are due in various installments through September 2021 at interest rates between 1.94% and 2.19% per annum. The notes are also collateralized by equipment and contain restrictive covenants. AHNI also has a $4.7 million line of credit with PNC, with interest calculated based on LIBOR plus 1.4%. As of December 31, 2016, there was no amount outstanding on the line of credit. Equipment Debt The Company’s equipment debt is comprised of financing arrangements between the Company and various lenders. Certain of the Company’s equipment debt obligations are subject to covenants with which it must comply on a quarterly or annual basis. The Company was in compliance with all such covenants except in regards to an agreement between Bank of the West (“BOW”) and one of its controlled joint ventures. Such financial covenants require the maintenance of minimum cash and cash equivalents and minimum EBITDA for the trailing four-quarter period at the end of each fiscal quarter. The equipment debt outstanding under this arrangement as of December 31, 2016 was $4.7 million. A waiver was obtained from BOW for the violation of the financial covenants for the period from July 1, 2016 to March 31, 2017. Principal Payments on Debt The annual principal maturities of long-term debt as of December 31, 2016 are as follows: Bank Credit Facilities (in thousands) Term Loan Revolving Credit Facility Equipment Under Capital Leases Equipment Loans Total Year ending December 31: 2017 $ 5,200 $ — $ 4,074 $ 12,628 $ 21,902 2018 5,200 21,500 4,065 10,086 40,851 2019 487,274 — 4,019 8,547 499,840 2020 — — 4,801 6,166 10,967 2021 — — 843 1,916 2,759 Total principal maturities, including imputed interest on equipment under capital leases $ 497,674 $ 21,500 $ 17,802 $ 39,343 $ 576,319 Less: imputed interest on equipment under capital leases (1,762 ) (1,762 ) Total principal maturities, excluding imputed interest on equipment under capital leases $ 16,040 $ 574,557

Income Per Common Share

Income Per Common Share	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Income Per Common Share	10. Income Per Common Share The following table sets forth the computation of basic and diluted income per share: Year Ended December 31, (in thousands except per share amounts) 2016 2015 2014 Numerator: Net income attributable to Alliance HealthCare Services, Inc. $ 493 $ 6,742 $ 10,618 Denominator: Weighted average shares-basic 10,866 10,741 10,669 Effect of dilutive securities: Stock options and RSUs 93 108 167 Weighted average shares-diluted 10,959 10,849 10,836 Income per common share attributable to Alliance HealthCare Services, Inc.: Basic $ 0.05 $ 0.63 $ 1.00 Diluted $ 0.04 $ 0.62 $ 0.98 Stock options excluded from the computation of diluted per share amounts: Weighted average shares for which the exercise price exceeds average market price of common stock 397 384 337 Average exercise price per share that exceeds average market price of common stock $ 27.56 $ 30.16 $ 34.75

Derivatives

Derivatives	12 Months Ended
	Dec. 31, 2016
Summary Of Derivative Instruments [Abstract]
Derivatives	11. Derivatives Cash Flow Hedges Interest Rate Cash Flow Hedges The Company has entered into multiple interest rate swap and cap agreements to hedge the future cash interest payments on portions of its variable-rate bank debt. At December 31, 2016, the Company had interest rate swap agreements to hedge approximately $15.5 million of its variable-rate bank debt or 2.7% of total debt. At December 31, 2015, the Company had interest rate swap and cap agreements to hedge approximately $265.9 million of its variable-rate bank debt or 46.0% of total debt. The Company’s interest rate cap agreements, which were effective December 2013 and had a notional amount of $250 million, matured on December 31, 2016. Over the next twelve months, the Company expects to reclassify $42,000 from accumulated other comprehensive loss to interest expense, net. The Company’s interest rate cash flow hedges consisted of the following as of December 31, 2016: Fair Value Asset (Liability) (1) (dollars in thousands) Notional Amount Fixed Payment Rate Maturity Date December 31, 2016 December 31, 2015 Liability Derivatives Derivatives designated as cash flow hedging instruments: One-month LIBOR plus 2.50% interest rate swap, effective December 2012 $ 1,119 3.75% December 2017 $ (3 ) $ (11 ) One-month LIBOR plus 2.00% interest rate swap, effective March 2013 1,172 2.87% April 2018 — (2 ) One-month LIBOR interest rate swap, effective December 2014 1,003 1.34% November 2019 (2 ) (7 ) One-month LIBOR plus 2.00% interest rate swap, effective December 2015 4,663 3.69% December 2021 (24 ) (54 ) One-month LIBOR interest rate swap, effective December 2015 1,169 1.37% December 2020 — (5 ) One-month LIBOR interest rate swap, effective September 2016 4,438 1.17% September 2021 33 — Derivatives not designated as cash flow hedging instruments: One-month LIBOR interest rate swap (2) 1,958 0.75% - 1.68% April 2017 - April 2020 (2 ) (7 ) Total liability derivatives $ 15,522 $ 2 $ (86 ) (1) The fair values of the interest rate swap assets and liabilities are included in “Other assets” and “Other accrued liabilities,” respectively, in the consolidated balance sheets. (2) The Company acquired eight non-designated interest rate swaps (the “AHNI Swaps”) as a result of the step acquisition of AHNI. The changes in fair market value of the AHNI Swaps are recorded in “Interest expense, net” as incurred. The following tables summarize the effect of derivative instruments for the periods indicated and the line items in the accompanying consolidated statements of income and comprehensive income where the results are recorded for cash flow hedges: Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Loss Reclassified from Accumulated OCI Amount of Loss Reclassified from Accumulated OCI into Income (Effective Portion) Location of (Loss) Gain Recognized in Amount of Gain Recognized in Income on Derivatives Income (Ineffective Portion) Year Ended December 31, into Income Year Ended December 31, Income on Derivatives Year Ended December 31, (in thousands) 2016 2015 (Effective Portion) 2016 2015 (Ineffective Portion) 2016 2015 Interest rate contracts $ 104 $ (246 ) Interest expense, net $ 417 $ 25 Interest expense, net $ — $ 1 Total $ 104 $ (246 ) $ 417 $ 25 $ — $ 1 The effect of non-designated derivative instruments on the consolidated statements of income and comprehensive income for the years ended December 31, 2016 and 2015 was immaterial.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies Purchase Commitments The Company has maintenance contracts with its equipment vendors for substantially all of its radiology and oncology equipment. The contracts are between 1 and 5 years from inception and extend through the year 2021 but may be canceled by the Company under certain circumstances. The Company’s total contract payments for the years ended December 31, 2016, 2015 and 2014 were $40.9 million, $40.4 million and $38.9 million, respectively. At December 31, 2016, the Company had binding equipment purchase commitments totaling $17.9 million. Leases The Company leases office and warehouse space and certain equipment under non-cancelable operating leases. The office and warehouse leases generally call for minimum monthly payments plus maintenance and inflationary increases. The future minimum payments under operating leases are as follows: (in thousands) Year ending December 31: 2017 $ 15,715 2018 13,872 2019 7,761 2020 6,559 2021 5,590 Thereafter 37,810 $ 87,307 The Company’s total rental expense, which includes short-term equipment rentals, for the years ended December 31, 2016, 2015 and 2014 was $23.0 million, $22.8 million and $16.8 million, respectively. Guarantees and Indemnities The Company has applied the disclosure provisions of ASC 460, “Guarantees,” to its agreements that contain guarantee or indemnification clauses. These disclosure provisions expand those required by ASC 440, “Commitments,” and ASC 450, “Contingencies,” by requiring a guarantor to disclose certain types of guarantees, even if the likelihood of requiring the guarantor’s performance is remote. The following is a description of arrangements in which the Company is the guarantor or indemnifies a party. In the normal course of business, the Company has made certain guarantees and indemnities, under which it may be required to make payments to a guaranteed or indemnified party, in relation to certain transactions. The Company indemnifies other parties, including customers, lessors, and parties to other transactions with the Company, with respect to certain matters. The Company has agreed to hold the other party harmless against losses arising from certain events as defined within the particular contract, which may include, for example, litigation or claims arising from a breach of representations or covenants. In addition, the Company has entered into indemnification agreements with its executive officers and directors and the Company’s bylaws contain similar indemnification obligations. Under these arrangements, the Company is obligated to indemnify, to the fullest extent permitted under applicable law, its current or former officers and directors for various amounts incurred with respect to actions, suits or proceedings in which they were made, or threatened to be made, a party as a result of acting as an officer or director. It is not possible to determine the maximum potential amount under these indemnification agreements due to the limited history of prior indemnification claims and the unique facts and circumstances involved in each particular agreement. Historically, payments made related to these indemnifications have been immaterial. At December 31, 2016, the Company has determined that no Litigation On February 10, 2015, Alliance Oncology was served with a lawsuit in the U.S. District Court for the Western District of Missouri by Dr. Barry Michael Driver. At the time the lawsuit was filed, the Plaintiff was a physician employed at Alliance Oncology’s Joplin, Missouri, Radiation Therapy Cancer Treatment Center. The Plaintiff alleged Alliance Oncology breached his employment agreement by failing to pay him in accordance with the terms of the contract. Alliance Oncology disputed Dr. Driver’s interpretation of the employment agreement and asserted Dr. Driver was paid appropriately. On September 9, 2015, the parties agreed to resolve the matter by mutual agreement whereby the Company agreed to pay the Plaintiff $1.5 million as full release of any and all claims. In November 2015, the Company was served with a lawsuit in the U.S. District Court for the Northern District of Ohio by Todd S. Elwert, DC, Inc. The Complaint alleges violations of the Junk Fax Prevention Act for allegedly sending an unsolicited advertisement to Plaintiff which promoted commercial availability and/or quality of the Company’s services. The Plaintiff further alleges that it is part of a class of similarly situated chiropractors who received the blast fax, and as such, requested class certification. The Company filed its response on December 17, 2015 and is currently in the discovery phase of the lawsuit. The Company intends to vigorously defend itself against the lawsuit and currently believes the ultimate disposition of these matters will not have a material adverse effect on its consolidated financial statements. Other Matters The Company from time to time is involved in routine litigation and regulatory matters incidental to the conduct of its business. The Company believes that resolution of such matters will not have a material adverse effect on its consolidated financial statements.

401(k) Savings Plan

401(k) Savings Plan	12 Months Ended
	Dec. 31, 2016
Compensation And Retirement Disclosure [Abstract]
401(k) Savings Plan	13. 401(k) Savings Plan Under the Company’s 401(k) Savings Plan (the “Plan”), all employees who are over 21 years of age are eligible to participate after attaining 30 days to 9 months of service, depending on the eligible participant’s work schedule. Employees may contribute between 1% and 50% of their annual compensation, subject to Internal Revenue Code limitations. The Company may make matching contributions depending on profitability. The Company may also make discretionary contributions. The Company’s contributions to the Plan of $543,000, $778,000 and $492,000 were recognized as expense in the consolidated statements of income and comprehensive income for the years ended December 31, 2016, 2015 and 2014, respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	14. Income Taxes The income tax expense shown in the consolidated statements of income and comprehensive income consists of the following: Year Ended December 31, (in thousands) 2016 2015 2014 Current: Federal $ 85 $ (91 ) $ 239 State 264 288 334 Total current 349 197 573 Deferred: Federal 2,030 5,864 5,858 State 473 475 896 Total deferred 2,503 6,339 6,754 Total income tax expense $ 2,852 $ 6,536 $ 7,327 Significant components of the Company’s net deferred tax liabilities are as follows: (in thousands) December 31, 2016 December 31, 2015 Basis differences in equipment $ (31,376 ) $ (24,162 ) Basis differences associated with acquired investments (24,467 ) (21,612 ) Basis differences in intangible assets (1,448 ) (287 ) Net operating losses 19,812 6,841 Accounts receivable 1,303 1,673 State income taxes 685 992 Accruals not currently deductible for income tax purposes 8,372 7,913 Deferred financing costs (4,391 ) — Other 5,692 5,622 Total deferred taxes (25,818 ) (23,020 ) Valuation allowance — — Net deferred taxes $ (25,818 ) $ (23,020 ) A reconciliation of expected total income tax expense, computed using the federal statutory rate on income is as follows: Year Ended December 31, (in thousands) 2016 2015 2014 U.S. federal tax benefit at statutory rates $ 6,664 $ 10,591 $ 9,861 State income taxes, net of federal benefit 479 496 800 Earnings from unconsolidated investees 451 1,187 1,629 Noncontrolling interest (5,945 ) (7,130 ) (5,209 ) Shareholder transaction costs 715 737 — Section 162(m) excess compensation 805 — — Changes in fair value of contingent consideration related to acquisition (508 ) — — Other 191 655 246 Income tax expense $ 2,852 $ 6,536 $ 7,327 As of December 31, 2016, the Company had net operating loss (“NOL”) carryforwards of approximately $50.0 million and $36.0 million for federal and state income tax purposes, respectively. These loss carryforwards will expire at various dates from 2017 through 2036. As of December 31, 2016, the Company also had alternative minimum tax credit carryforwards of $4.6 million with no expiration date. As of December 31, 2016, the Company has provided a liability for $272,000 of unrecognized tax benefits related to various federal and state income tax matters. The tax-effected amount that would reduce the Company’s effective income tax rate if recognized is $219,000. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: (in thousands) 2016 2015 2014 Unrecognized tax benefits at January 1 $ 229 $ 269 $ 287 Increases for positions taken in current year 97 51 64 Increases for positions taken in a prior year 5 — 31 Decreases for positions taken in a prior year (9 ) (11 ) — Decreases for lapses in the applicable statute of limitations (50 ) (80 ) (113 ) Decreases for settlements with taxing authorities — — — Unrecognized tax benefits at December 31 $ 272 $ 229 $ 269 The Company recognizes accrued interest and penalties related to unrecognized tax benefits in “Income tax expense.” As of December 31, 2016, the Company had approximately $12,000 in accrued interest and penalties related to unrecognized tax benefits. The Company is subject to U.S. federal income tax as well as income tax of multiple state tax jurisdictions. The Company’s federal tax returns are currently open to audit under the statute of limitations by the Internal Revenue Service for the years ended December 31, 2013 through 2016. The Company’s state income tax returns are open to audit under the applicable statutes of limitations for the years ended December 31, 2012 through 2016. The Company does not anticipate a significant change to the total amount of unrecognized tax benefits within the next 12 months.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions	15. Related Party Transactions Ownership Structure On September 16, 2015, Tahoe agreed to purchase approximately 5,537,945 shares of Company common stock from funds managed by the Selling Stockholders. On December 12, 2016, the Company announced it had received a letter describing a non-binding proposal from Tahoe to acquire all of the outstanding common shares of Alliance that are not currently owned by Tahoe. Management Agreements The Company had direct ownership in two unconsolidated investees at December 31, 2016. As discussed in Note 3, the Company obtained an additional 15.5% interest in one of its unconsolidated investees, AHNI, on August 1, 2015, thereby increasing its ownership position in AHNI to 65.5% and giving it a controlling interest. The following table summarizes revenues from management agreements with unconsolidated equity investees: Year ended December 31, (in thousands) 2016 2015 2014 Revenue from management agreements $ 1,473 $ 6,099 $ 9,134 The Company provides services as part of its ongoing operations for and on behalf of the unconsolidated equity investees, which reimburse the Company for the actual amount of the expenses incurred. The Company records the expenses as cost of revenues and the reimbursement as revenue in its consolidated statements of income and comprehensive income. The following table summarizes the revenue and reimbursed expenses related to the Company’s unconsolidated equity investees: Year ended December 31, (in thousands) 2016 2015 2014 Revenue and reimbursed expenses $ 1,013 $ 4,879 $ 7,320

Investments in Unconsolidated I

Investments in Unconsolidated Investees	12 Months Ended
	Dec. 31, 2016
Equity Method Investments And Joint Ventures [Abstract]
Investments in Unconsolidated Investees	16. Investments in Unconsolidated Investees The Company has direct ownership in two unconsolidated investees at December 31, 2016. The Company owns 15% and 50% of these investees, respectively, and provides management services under agreements with these investees, expiring at various dates through 2025. Both of these investees are accounted for under the equity method because the Company does not exercise control over the operations of these investees. On August 1, 2015, the Company obtained an additional 15.5% interest in a previously unconsolidated investee, AHNI, thereby increasing its ownership position to 65.5% and giving it a controlling interest. Prior to August 1, 2015, the Company’s interest in AHNI was deemed a noncontrolling interest and, accordingly, the Company accounted for the investment using the equity method. Set forth below are certain balance sheet and operating results for the aggregate of the Company’s unconsolidated investees. The operating results for AHNI from January 1, 2015 through its acquisition on August 1, 2015 are included in the results for the year ended December 31, 2015: (in thousands) December 31, 2016 December 31, 2015 Balance sheet data: Current assets $ 2,860 $ 2,644 Noncurrent assets 111 273 Current liabilities 760 676 Noncurrent liabilities 32 35 Year Ended December 31, (in thousands) 2016 2015 2014 Combined operating results: Revenues $ 10,389 $ 20,796 $ 27,735 Expenses 3,055 9,038 13,597 Net income 7,333 11,758 14,138 Earnings from unconsolidated investees 1,290 3,391 4,654

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Segment Information	17. Segment Information The following table summarizes the Company’s revenue by segment: Year Ended December 31, (in thousands) 2016 2015 2014 Revenue: MRI $ 197,316 $ 183,893 $ 180,815 PET/CT 126,927 128,356 133,224 Other radiology 26,556 27,378 29,424 Radiology 350,799 339,627 343,463 Oncology 107,220 99,957 92,924 Interventional 45,562 33,193 — Corporate / Other 1,968 277 — Total $ 505,549 $ 473,054 $ 436,387 Adjusted EBITDA represents net income before: income tax expense; interest expense, net; depreciation expense; amortization expense; share-based payment; severance and related costs; noncontrolling interest in subsidiaries; restructuring charges; transaction costs; shareholder transaction costs; impairment charges; legal matters expense, net; changes in fair value of contingent consideration related to acquisitions; non-cash gain on step acquisition; and other non-cash charges, net, which include non-cash (gains) losses on sales of equipment Adjusted EBITDA is the most frequently used measure of each segment’s performance and is commonly used in setting performance goals. The following table summarizes the Company’s Adjusted EBITDA: Year Ended December 31, (in thousands) 2016 2015 2014 Adjusted EBITDA (1) Radiology $ 96,828 $ 94,475 $ 104,681 Oncology 46,609 43,112 41,846 Interventional 3,935 5,175 — Corporate / Other (15,904 ) (11,502 ) (10,772 ) Total $ 131,468 $ 131,260 $ 135,755 (1) Adjusted EBITDA by segment includes inter-segment operating expense allocations from Corporate / Other to Radiology and Oncology of $18.9 million and $6.0 million, respectively, in 2016, $18.9 million and $6.4 million, respectively, in 2015, and $20.9 million and $4.9 million, respectively, in 2014. The reconciliation of income before income taxes, earnings from unconsolidated investees, and noncontrolling interest to total Adjusted EBITDA is shown below: Year Ended December 31, (in thousands) 2016 2015 2014 Income before income taxes, earnings from unconsolidated investees, and noncontrolling interest $ 19,040 $ 30,260 $ 28,174 Earnings from unconsolidated investees 1,290 3,391 4,654 Interest expense, net 34,506 26,241 24,693 Depreciation expense 54,972 48,595 54,971 Amortization expense 10,561 9,325 7,880 Share-based payment (included in “ expenses ” 3,176 1,701 1,515 Severance and related costs 3,910 1,347 2,517 Restructuring charges (Note 3) 1,635 1,327 2,602 Transaction costs 1,886 3,296 2,344 Shareholder transaction costs 4,219 1,853 — Impairment charges 632 6,817 308 Legal matters expense, net 106 6,915 5,587 Changes in fair value of contingent consideration related to acquisitions (included in “Other income, net”) (4,790 ) — — Non-cash gain on step acquisition (included in “Other income, net”) — (10,672 ) — Other non-cash charges (included in “Other income, net”) 325 864 510 Total Adjusted EBITDA $ 131,468 $ 131,260 $ 135,755 The following table summarizes the Company’s identifiable assets by segment: As of December 31, (in thousands) 2016 2015 2014 Identifiable assets: Radiology $ 301,137 $ 280,497 $ 211,004 Oncology 256,456 213,698 182,880 Interventional 82,221 83,480 — Corporate / Other 20,050 25,985 63,911 Total $ 659,864 $ 603,660 $ 457,795 The following table summarizes the Company’s equipment capital expenditures by segment: As of December 31, (in thousands) 2016 2015 2014 Capital expenditures: Radiology $ 50,511 $ 27,478 $ 18,311 Oncology 3,043 21,694 3,994 Interventional 155 1,287 — Corporate / Other 2,692 5,052 10,081 Total $ 56,401 $ 55,511 $ 32,386

Quarterly Financial Data

Quarterly Financial Data	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data (Unaudited)	18. Quarterly Financial Data (Unaudited) The following table sets forth selected unaudited quarterly information for the Company’s last eight fiscal quarters derived from the Company’s interim financial statements. Such financial statements have been prepared on the same basis as the consolidated financial statements and all necessary adjustments (which consisted only of normal recurring adjustments) have been included to present fairly the results of such periods when read in conjunction with the consolidated financial statements and related notes included elsewhere herein. Quarter Ended Mar. 31, Jun. 30, Sep. 30, Dec. 31, (in thousands except per share amounts) 2016 2016 2016 2016 Revenues $ 123,725 $ 125,317 $ 127,121 $ 129,386 Cost of revenues, excluding depreciation and amortization 70,914 69,939 71,132 73,761 Income before income taxes, earnings from unconsolidated investees and noncontrolling interest 2,205 8,016 7,407 1,412 Net income 3,402 6,188 5,827 2,061 Net (loss) income attributable to Alliance HealthCare Services, Inc. (1,190 ) 2,459 1,358 (2,134 ) (Loss) income per common share attributable to Alliance HealthCare Services, Inc.: Basic $ (0.11 ) $ 0.23 $ 0.12 $ (0.20 ) Diluted $ (0.11 ) $ 0.23 $ 0.12 $ (0.20 ) Quarter Ended Mar. 31, Jun. 30, Sep. 30, Dec. 31, (in thousands except per share amounts) 2015 2015 2015 2015 Revenues $ 109,429 $ 118,504 $ 120,784 $ 124,337 Cost of revenues, excluding depreciation and amortization 61,886 67,485 67,057 72,676 Income before income taxes, earnings from unconsolidated investees and noncontrolling interest 6,507 284 17,571 5,898 Net income 6,098 2,942 13,065 5,010 Net income (loss) attributable to Alliance HealthCare Services, Inc. 1,751 (1,961 ) 7,204 (252 ) Income (loss) per common share attributable to Alliance HealthCare Services, Inc.: Basic $ 0.16 $ (0.18 ) $ 0.67 $ (0.02 ) Diluted $ 0.16 $ (0.18 ) $ 0.67 $ (0.02 ) The Company experiences seasonality in the revenues and margins generated for its services. First and fourth quarter revenues are typically lower than those from the second and third quarters. First quarter revenue is affected primarily by fewer calendar days and inclement weather, typically resulting in fewer patients being scanned or treated during the period. Fourth quarter revenues are affected by holiday and client and patient vacation schedules, resulting in fewer scans or treatments during the period. The variability in margins is higher than the variability in revenues due to the fixed nature of our costs. The Company also experiences fluctuations in the revenues and margins generated due to acquisition activity and general economic conditions, including recession or economic slowdown. For information regarding acquisitions, transactions and impairment charges recorded in 2016, 2015 and 2014, see Note 3 and Note 6.

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2016
Valuation And Qualifying Accounts [Abstract]
Schedule II - Valuation and Qualifying Accounts	ALLIANCE HEALTHCARE SERVICES, INC. AND SUBSIDIARIES SCHEDULE II—VALUATION AND QUALIFYING ACCOUNTS (in thousands) Balance at Beginning of Period Additions Deductions (Bad offs, net of Recoveries) Balance at End of Period Year ended December 31, 2016 Allowance for doubtful accounts $ 5,461 $ 2,255 $ (3,708 ) $ 4,008 Year ended December 31, 2015 Allowance for doubtful accounts $ 4,055 $ 4,107 $ (2,701 ) $ 5,461 Year ended December 31, 2014 Allowance for doubtful accounts $ 5,158 $ 2,634 $ (3,737 ) $ 4,055

Summary of Significant Accoun27

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Principles of Consolidation and Basis of Financial Statement Presentation	Principles of Consolidation and Basis of Financial Statement Presentation The accompanying audited consolidated financial statements of the Company include the assets, liabilities, revenues and expenses of all subsidiaries over which the Company exercises control. Intercompany transactions have been eliminated. The Company evaluates participating rights in its assessment of control in determining consolidation of joint venture partnerships. The Company records noncontrolling interest related to its consolidated subsidiaries that are not wholly-owned. Investments in non-consolidated investees over which it exercises significant influence but does not control are accounted for under the equity method. The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“generally accepted accounting principles,” or “GAAP”).
Cash and Cash Equivalents	Cash and Cash Equivalents The Company classifies short-term investments with original maturities of three months or less as cash equivalents.
Accounts Receivable	Accounts Receivable The Company provides shared and single-user diagnostic imaging and oncology equipment and technical support services to the healthcare industry and directly to patients on an outpatient basis. Substantially all of the Company’s accounts receivable are due from hospitals, other healthcare providers and health insurance providers, including Medicare, located throughout the U.S. A substantial portion of the Company’s services are provided pursuant to long-term contracts with hospitals and other healthcare providers or directly to patients. Estimated credit losses are provided for in the consolidated financial statements.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments which potentially subject the Company to a concentration of credit risk principally consist of cash, cash equivalents and accounts receivable. The Company invests available cash in cash equivalents and money market securities of high-credit-quality financial institutions. Cash and cash equivalents in excess of federally insured limits were $ 15.4 million and $29.5 million at December 31, 2016 and 2015, respectively. As of December 31, 2016 and 2015, the Company’s accounts receivable were primarily from clients in the healthcare industry and third-party payers. No individual customer represented more than 10% of the Company’s accounts receivable at December 31, 2016 and 2015. To reduce credit risk, the Company performs periodic credit evaluations of its clients, but does not generally require advance payments or collateral. Credit losses to clients in the healthcare industry have not been material. The provision for doubtful accounts was 0.4%, 0.6%, and 0.6% of revenues in 2016, 2015 and 2014, respectively.
Plant, Property and Equipment	Plant, Property and Equipment The majority of the Company’s major medical equipment is stated at cost and is depreciated using the straight-line method over the initial estimated life to an estimated residual value, which is between 5% and 10% of original cost. If the Company continues to operate the equipment beyond its initial estimated life, the residual value is then depreciated to a nominal salvage value over 1 to 2 years. The estimated service lives for property and equipment are as follows: Estimated Useful Life Furniture and fixtures 5 to 10 years Office equipment 2 to 7 years Transportation and service equipment 2 to 10 years Major equipment 2 to 10 years Tenant improvements 5 to 25 years Buildings 7 years Routine maintenance and repairs are charged to expense as incurred. Major repairs and purchased software and hardware upgrades, which extend the life of or add value to the equipment, are capitalized and depreciated over the remaining useful life.
Assets Under Capital Leases	Assets Under Capital Leases Assets under capital leases are recorded at the lower of the net present value of the minimum lease payments or the fair value of the leased asset at the inception of the lease. Amortization expense is recognized using the straight-line method over the shorter of the estimated useful life of the asset or the term of the related lease and is included in depreciation expense.
Goodwill and Intangible Assets	Goodwill and Intangible Assets Accounting Standards Codification (“ASC”) 350, “Intangibles – Goodwill and Other,” requires that goodwill and indefinite-lived intangible assets are not amortized but instead tested for impairment at least annually at the reporting unit level. In addition, ASC 350 defines a reporting unit as an operating segment or one level below an operating segment (also known as a component). A component of an operating segment is a reporting unit under ASC 350 if the component constitutes a business for which discrete financial information is available and reviewed by management. The Company has evaluated ASC 350 and concluded there are three operating segments: Radiology, Oncology and Interventional. The Company has assessed that each component listed above meets the definition of a reporting unit based on the conclusions that each component constitutes a business, discrete financial information is available for each component, and management regularly reviews the results of such financial information. In accordance with ASC 350, the Company performs an annual impairment test in the fourth quarter for goodwill and indefinite-lived intangible assets or more frequently if an event occurs or circumstances change that would more-likely-than-not reduce the fair value of a reporting unit below its carrying amount. Such indicators include a sustained significant decline in the Company’s market capitalization or a significant decline in expected future cash flows due to changes in company-specific factors or the broader business climate. In evaluating goodwill for impairment, the Company first assesses qualitative factors to determine whether it is more-likely-than-not that the fair value of a reporting unit is less than its carrying amount. If the Company concludes that it is more-likely-than-not that the fair value of a reporting unit is less than its carrying amount, the Company conducts a two-step quantitative goodwill impairment test. First, for each reporting unit, the Company compares its estimated fair value with its net book value. If the estimated fair value exceeds its net book value, goodwill is deemed not to be impaired, and no further testing is necessary. If the estimated fair value does not exceed its net book value, the Company then performs a second test to calculate the amount of impairment, if any. To determine the amount of any impairment, the Company determines the implied fair value of goodwill. Specifically, the Company determines the fair value of all of the assets and liabilities of the reporting unit, including any unrecognized intangible assets, in a hypothetical calculation that yields the implied fair value of goodwill. If the implied fair value of goodwill is less than the recorded goodwill, the Company records an impairment charge for the difference. The impairment analysis in the first step utilizes two primary approaches to calculate the fair value of the reporting unit: the discounted cash flow (“DCF”) method and the Guideline Public Company (“GPC”) method. Under the DCF method, fair value is measured as the present worth of anticipated future net cash flows generated by a business. In a multi-period model, net cash flows attributable to a business are forecast for an appropriate period and then discounted to present value using an appropriate discount rate. In a single-period model, net cash flow or earnings for a normalized period are capitalized to reach a determination of present value. The methods, key assumptions, degree of uncertainty associated with the key assumptions and the potential events or changes in circumstances that could reasonably be expected to negatively affect the key assumptions with respect to the reporting unit are the estimated future net cash flows generated and the discount rate applied to capture the associated risks. The ability to achieve anticipated future net cash flows is subject to numerous assumptions and risks, including company-specific risks such as the ability to maintain and grow revenues, maintain or improve operating margins, control costs and anticipate working capital requirements. The anticipated future net cash flows are also dependent on industry-level factors, such as the impact of the Patient Protection and Affordable Care Act of 2010, on patient volumes and cost-reimbursement levels and continued availability of qualified doctors and other medical professionals who are necessary to staff the Company’s operations, among other potential impacts. Under the GPC method, value is estimated by comparing the subject company to similar companies with publicly-traded ownership interests. Guideline companies are selected based on comparability to the subject company, and valuation multiples are calculated and applied to subject company operating data. The key assumption used in connection with the GPC method focuses on identifying guideline companies that operate in the same (or similar) line of business as the reporting units with the same (or similar) operating characteristics. Eligible companies are selected based on Global Industry Classification Standard codes, Standard Industrial Classification codes, company descriptions, and industry affiliations. Considered factors include relative risk, profitability, and growth considerations of the reporting unit relative to the guideline companies. Value estimates for the reporting unit involve using multiples of market value of invested capital excluding cash to revenue and earnings before interest, income taxes, depreciation and amortization (“EBITDA”). Valuations derived using the GPC method rely on information primarily obtained from available industry market data and publicly available filings with the Securities and Exchange Commission (“SEC”). In testing indefinite-lived intangible assets for impairment, the Company first assesses qualitative factors to determine whether it is more-likely-than-not that the fair value of an indefinite-lived intangible asset is less than its carrying amount. If the Company concludes that it is more-likely-than-not that the fair value of an indefinite-lived intangible asset is less than its carrying amount, the Company conducts a two-step quantitative impairment test, which consist of a comparison of the fair value to its carrying amount. If the carrying amount exceeds its fair value, an impairment loss is recognized in an amount equal to that excess. ASC 350 also requires finite-lived intangible assets to be amortized over their respective estimated useful lives to their estimated residual values and reviewed for impairment in accordance with ASC 360, “Property, Plant, and Equipment.” For additional information, see Note 6.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company accounts for long-lived assets in accordance with the provisions of ASC 360, which requires that long-lived assets be reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to undiscounted future net cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated undiscounted future cash flows, an impairment charge is recognized for the amount by which the carrying amount of the asset exceeds the fair value of the asset. Assets to be disposed of are reported at the lower of the carrying amount or fair value less costs to sell.
Purchase Accounting	Purchase Accounting In accordance with GAAP, the assets acquired and liabilities assumed in an acquired business are recorded at their estimated fair values on the date of acquisition. The difference between the purchase price amount and the net fair value of assets acquired and liabilities assumed is recognized as goodwill if it exceeds the estimated fair value and as a bargain purchase gain if it is below the estimated fair value. Determining the fair value of assets acquired and liabilities assumed requires management’s judgment, often utilizes independent valuation experts and involves the use of significant estimates and assumptions with respect to the timing and amounts of future cash inflows and outflows, discount rates, market prices and asset lives, among other items. The judgments made in the determination of the estimated fair value assigned to the assets acquired and liabilities assumed, as well as the estimated useful life of each asset and the duration of each liability, can materially impact the financial statements in periods after acquisition, such as through depreciation and amortization expense. Acquisitions of entities over which the Company exercises control have been recorded using the acquisition method of accounting and, accordingly, results of their operations have been included in the Company’s consolidated financial statements as of the effective date of each respective acquisition.
Revenue Recognition	Revenue Recognition The majority of the Company’s revenues are derived directly from healthcare providers and are primarily for radiology and oncology services. To a lesser extent, revenues are generated from direct billings to third-party payers or patients which are recorded net of contractual discounts and other arrangements for providing services at less than established patient billing rates. Revenues from billings to third-party payers and patients amounted to approximately 25%, 20% and 20% of revenues for the years ended December 31, 2016, 2015 and 2014, respectively. No single customer accounted for more than 10% of consolidated revenues in each of the years ended December 31, 2016, 2015 and 2014. The Company recognizes revenue in accordance with ASC 605, “Revenue.” As the price is pre-determined, all revenues are recognized at the time the delivery of service has occurred and collectability is reasonably assured which is based upon contract terms with healthcare providers and negotiated rates with third-party payers and patients. The Company also records revenue from management services that it performs based upon management service contracts with predetermined pricing. Revenues from these services amounted to approximately 0.5%, 2% and 2% of total revenue for the years ended December 31, 2016, 2015 and 2014, respectively. These revenues are recorded in the period in which the service is performed and collections of the billed amounts are reasonably assured in accordance with ASC 605.
Share-based Payment	Share-based Payment Share-based compensation expense is based on the grant date fair value estimated in accordance with ASC 718, “Compensation—Stock Compensation.” This value is recognized ratably over the requisite service periods. The Company followed the alternative transition method as described in ASC 718 for computing its beginning additional paid-in capital pool. In addition, the Company treats the tax deductions from stock options as being realized when they reduce taxes payable in accordance with the principles and timing under the relevant tax law. The Company uses the Black-Scholes option pricing model to value the compensation expense associated with share-based payment awards. The fair value of each option award is estimated on the date of grant using the Black-Scholes option pricing model using certain assumptions (see Note 4). In addition, forfeitures are estimated when recognizing compensation expense and the estimate of forfeitures will be adjusted over the requisite service period to the extent that actual forfeitures differ, or are expected to differ, from such estimates. Changes in estimated forfeitures will be recognized through a cumulative catch-up adjustment in the period of change and will also impact the amount of compensation expense to be recognized in future periods.
Derivatives	Derivatives The Company accounts for derivative instruments and hedging activities in accordance with the provisions of ASC 815, “Derivatives and Hedging.” On the date the Company enters into a derivative contract, management may designate the derivative as a hedge of the identified exposure. The Company formally documents all relationships between hedging instruments and hedged items, as well as the risk-management objective and strategy for undertaking various hedge transactions. In this documentation, the Company specifically identifies the firm commitment or forecasted transaction that has been designated as a hedged item and states how the hedging instrument is expected to hedge the risks related to the hedged item. The Company formally measures effectiveness of its hedging relationships, both at hedge inception and on an ongoing basis, in accordance with its risk management policy. The Company discontinues hedge accounting prospectively: (i) if it is determined that the derivative is no longer effective in offsetting the change in the cash flows of a hedged item; (ii) when the derivative expires or is sold, terminated or exercised; (iii) because it is probable that the forecasted transaction will not occur; (iv) because a hedged firm commitment no longer meets the definition of a firm commitment; or (v) if management determines that designation of the derivative as a hedge instrument is no longer appropriate. The Company’s derivatives are recorded on the balance sheet at fair value. For derivatives accounted for as cash flow hedges, any unrealized gains or losses on fair value are included in comprehensive income (loss), net of tax, assuming perfect effectiveness. Any ineffectiveness is recognized in earnings. Amounts recorded in comprehensive income (loss) are reclassified to earnings when the hedged item impacts earnings.
Income Taxes	Income Taxes The provision for income taxes is determined in accordance with ASC 740, “Income Taxes.” Deferred tax assets and liabilities are determined based on the temporary differences between the financial reporting and tax bases of assets and liabilities, applying enacted statutory tax rates in effect for the year in which the differences are expected to reverse. Future income tax benefits are recognized only to the extent that the realization of such benefits is considered to be more likely than not. The Company regularly reviews its deferred tax assets for recoverability and establishes a valuation allowance, when it is more likely than not that such deferred tax assets will not be recoverable, based on historical taxable income, projected future taxable income, and the expected timing of the reversals of existing temporary differences.
Fair Values of Financial Instruments	Fair Values of Financial Instruments The Company uses the following methods and assumptions in estimating fair value disclosure for financial instruments: • Cash and cash equivalents The carrying amounts of cash and cash equivalents reported in the consolidated balance sheets approximate fair value due to the short-term maturity or variable rates of these instruments. • Debt Debt is recorded in the financial statements at historical cost. The carrying amounts of variable-rate borrowings at December 31, 2016 and 2015 approximate fair value estimates based on current market rates and credit spreads for similar debt instruments. • Contingent consideration Contingent consideration related to acquisitions at December 31, 2016 and 2015 is carried at fair value using probability-adjusted performance estimates . • Mandatorily redeemable noncontrolling interest The carrying amount of mandatorily redeemable noncontrolling interest related to the acquisition of PRC Associates, LLC (“PRC”) at December 31, 2016 and 2015 approximates fair value using the estimated implied fair value based on the Company’s ownership percentage . Further discussion of the mandatorily redeemable noncontrolling interest is disclosed in Note 3. • Derivative instruments Fair value was determined based on the income approach and standard valuation techniques to convert future amounts to a single present amount and approximates the net gains and losses that would have been realized if the contracts had been settled at each period-end. ASC 820, “Fair Value Measurement,” applies to all assets and liabilities that are being measured and reported at fair value on a recurring basis. ASC 820 requires disclosure that establishes a framework for measuring fair value by establishing a hierarchy for ranking the quality and reliability of the information used to determine fair values. The statement requires that assets and liabilities carried at fair value be classified and disclosed in one of the following three categories: Level 1 Quoted market prices in active markets for identical assets or liabilities; Level 2 Observable market-based inputs or unobservable inputs, including identical securities in inactive markets or similar securities in active markets that are corroborated by market data; or Level 3 Unobservable inputs that are not corroborated by market data.
Self-Insurance	Self-Insurance The Company has purchased large deductible insurance policies for its workers’ compensation, auto liability, general liability, and professional liability exposures. The Company currently retains the first $ 250,000 of loss for workers’ compensation and auto liability and $100,000 for general and professional liability. The Company’s policy is to accrue amounts equal to the actuarially estimated costs to settle open claims of insureds, as well as an estimate of the cost of insured claims that have been incurred but not reported. The Company develops information about the size of the ultimate claims based on historical experience, current industry information and actuarial analysis, and evaluates the estimates for claim loss exposure on an annual basis. Assets and liabilities are reported in gross amounts in “Other assets” and “Other accrued liabilities” and “Other liabilities,” respectively. The Company believes that adequate provision has been made in the consolidated financial statements for these liabilities. The most significant assumptions used in the estimation process include determining the trend in costs, the expected cost of claims incurred but not reported and the expected costs to settle or pay damage awards with respect to unpaid claims. Recorded liabilities are based upon estimates, and while management believes that the estimates of loss are reasonable, the ultimate liability may be in excess of or less than the recorded amounts. Due to the inherent volatility of actuarially determined loss estimates, it is reasonably possible that the Company could experience changes in estimated losses that could be material to net income. If the Company’s actual liability exceeds its estimates of loss, its future earnings, cash flows and financial condition would be adversely affected.
Advertising Costs	Advertising Costs The Company expenses all advertising costs as incurred. Advertising costs were $ 2.0 million, $1.3 million and $1.4 million for the years ended December 31, 2016, 2015 and 2014, respectively.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
Comprehensive Income (Loss)	Comprehensive Income (Loss) The Company reports comprehensive income (loss) in accordance with ASC 220, “Comprehensive Income.” For the years ended December 31, 2016, 2015 and 2014, the Company entered into multiple interest rate cap agreements and interest rate swap agreements, as discussed in Note 11. Assuming perfect effectiveness, any unrealized gains and losses related to the swaps and caps that qualify for cash flow hedge accounting are classified as a component of comprehensive income (loss), net of tax. Any ineffectiveness is recognized in earnings.
Segment Reporting	Segment Reporting Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker (“CODM”) in deciding how to allocate resources and in assessing performance. In accordance with ASC 280, “Segment Reporting,” and based on the nature of the financial information that is received by the CODM, the Company operates in three reportable segments: Radiology, Oncology and Interventional. Each of these segments, on a stand-alone basis, provides and makes available its respective medical services in similar settings and operates within a singular regulatory environment. Further, management assesses the Company’s segment operations and each segment’s degree of efficiency and performance based on this structure of financial reporting and primarily makes operating decisions from these reportable segment results. All intercompany revenues, expenses, payables and receivables are eliminated in consolidation and are not reviewed when evaluating segment performance. Each segment’s performance is evaluated based on revenue and Adjusted EBITDA. There is no aggregation of operating segments in the Company’s determination of reportable segments. Prior to January 1, 2016, the Company operated in two reportable segments: Radiology and Oncology. The Interventional Division, the third operating segment, was formed in February of 2015 with the acquisition of The Pain Center of Arizona (“TPC”). In October of 2015 and in January of 2016, the Company acquired two pain practices in Florida, creating the current foundation of its Interventional segment. With the completion of its third acquisition, the Company began reporting Interventional services as a separate segment. The historical activity of the Interventional segment and Corporate / Other have been recast for consistent presentation for all periods presented.
Net Income Per Share	Net Income Per Share Basic net income per share is calculated b y dividing net income by the weighted average number of common shares outstanding during the year. Except where the result would be anti-dilutive, diluted net income per share is calculated by dividing net income by the sum of the weighted average number of common shares and potentially dilutive common shares outstanding during the period. Potentially dilutive common shares include dilutive outstanding stock options, unvested restricted stock and unvested restricted stock units (“RSUs”).
Reclassifications	Reclassifications Certain prior period amounts have been recast to reflect the effects from changes to the Company’s reportable segments and the adoption of recent accounting pronouncements (see Note 17 and “Recent Accounting Pronouncements below”).
Recent Accounting Pronouncements	Recent Accounting Pronouncements Revenue Recognition In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, “Revenue from Contracts with Customers (Topic 606),” to clarify and converge the revenue recognition principles under GAAP and International Financial Reporting Standards and to develop guidance that would streamline and enhance revenue recognition requirements while also providing a more robust framework for addressing revenue issues. ASU 2014-09 outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry specific guidance. Key provisions of the ASU involve a 5-step model specific to recognizing revenue derived from customer contracts. In addition, ASU 2014-09 provides implementation guidance on several other important topics, including the accounting for certain revenue-related costs. The Company will be required to capitalize costs to acquire new contracts, whereas currently, the Company expenses those costs as incurred. In August 2015, the FASB issued an amendment to provide a one-year deferral of the effective date to annual reporting periods beginning on or after December 15, 2017. Early adoption of the standard as of December 15, 2016 (for interim and annual reporting periods beginning after that date) is permitted. The Company is currently working through an adoption plan, including identifying its revenue streams and completing a preliminary analysis of how it currently accounts for revenue transactions compared to the revenue accounting required under the new standard. The Company intends to complete its adoption plan in 2017. This plan includes a review of transactions supporting each revenue stream to determine the impact of accounting treatment under ASC 606 and the completion of a rollout plan for implementation of the new standard with affected functions in its organization. Because of the nature of the work that remains, at this time the Company is unable to reasonably estimate the impact of adoption on its consolidated financial statements. ASU 2014-09 will be effective for the Company beginning on January 1, 2018. Going Concern In August 2014, the FASB issued ASU 2014-15, “Presentation of Financial Statements—Going Concern (Subtopic 205-40).” Under GAAP, a going concern is presumed unless and until an entity’s liquidation becomes imminent. When an entity’s liquidation becomes imminent, financial statements should be prepared under the liquidation basis of accounting in accordance with Subtopic 205-30, “Presentation of Financial Statements—Liquidation Basis of Accounting.” However, there may be conditions or events that raise substantial doubt about an entity’s ability to continue as a going concern, even if liquidation is not imminent. In those situations, financial statements should continue to be prepared under the going concern basis of accounting. ASU 2014-15 provides guidance about management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to determine whether to disclose information about relevant conditions and events. ASU 2014-15 is effective for annual periods ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. The adoption of ASU 2014-15 for the year ended December 31, 2016 did not have a material impact on the Company’s consolidated financial statements. Simplifying the Presentation of Debt Issuance Costs In April 2015, the FASB issued ASU 2015-03, “Simplifying the Presentation of Debt Issuance Cost” that changes the presentation of debt issuance costs in financial statements. ASU 2015-03 requires entities to present such costs in the balance sheet as a direct reduction to the related debt liability rather than as a deferred cost (i.e., an asset) as required by prior guidance. In August 2015, the FASB issued clarifying authoritative guidance for debt issuance costs incurred in connection with line-of-credit arrangements. The guidance states that an entity should defer and present these debt issuance costs as an asset and subsequently amortize the deferred debt issuance costs ratably over the term of the line-of-credit arrangement. ASU 2015-03 does not change the recognition or measurement of debt issuance costs and is effective for fiscal years beginning after December 15, 2015. The guidance is required to be applied retrospectively to all prior periods presented. As of December 31, 2015, the Company had $6.6 million in deferred financing costs, net that was reclassified to offset long-term debt, net of current portion. Other than the revised balance sheet presentation and related disclosures, the adoption of the guidance on January 1, 2016 did not have a material impact on the Company’s consolidated financial statements. Balance Sheet Classification of Deferred Taxes In November 2015, the FASB issued ASU 2015-17, “Balance Sheet Classification of Deferred Taxes,” which requires entities to present deferred tax assets (“DTAs”) and deferred tax liabilities (“DTLs”) as noncurrent in a classified balance sheet. The ASU simplifies the current guidance, which requires entities to separately present DTAs and DTLs as current and noncurrent in a classified balance sheet. The adoption of ASU 2015-17 is effective for publicly traded business entities for annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. Early adoption is permitted. The Company elected to early-adopt this guidance and applied it retrospectively to periods presented in the consolidated financial statements. As of December 31, 2015, the Company had $6.5 million in DTAs that was reclassified to offset long-term DTLs. Other than the revised balance sheet presentation and related disclosures, the adoption of ASU 2015-17 on January 1, 2016 did not have a material impact on the Company’s consolidated financial statements. Leases In February 2016, the FASB issued ASU 2016-02, “Leases” (Topic 842), to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. The ASU supersedes the current guidance. The primary difference between current guidance and ASU 2015-02 is the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous GAAP. ASU 2016-02 also requires an entity to separate the lease components from the non-lease components (for example, maintenance services or other activities that transfer a good or service to the customer) in a contract. Only the lease components must be accounted for in accordance with this guidance. ASU 2016-02 is effective for publicly traded business entities for annual reporting periods beginning after December 15, 2018, including interim reporting periods within that reporting period. Early adoption is permitted. ASU 2016-02 will be effective for the Company beginning on January 1, 2019. The Company is assessing the impact, if any, that the adoption of ASU 2016-02 may have on the Company’s consolidated financial statements . Share-based Payments In March 2016, the FASB issued ASU 2016-09, “Compensation – Stock Compensation (Topic 718),” which simplifies several aspects of the accounting for employee share-based payment transactions for both public and nonpublic entities, including the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. ASU 2016-09 is effective for public business entities for annual reporting periods beginning after December 15, 2016, including interim periods within those annual reporting periods. Early adoption is permitted. ASU 2016-09 will be effective for the Company beginning on January 1, 2017. The Company does not anticipate that the adoption of ASU 2016-09 will have a material impact on its consolidated financial statements. Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments,” which is intended to reduce diversity in the classification of transactions related to debt prepayment or debt extinguishment costs, zero-coupon debt instruments settlement, contingent consideration payments made after a business combination, insurance claims settlement and corporate-owned life insurance settlement, distributions from equity method investments and beneficial interests in securitization transactions. This guidance is effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. Early adoption is permitted. ASU 2016-15 will be effective for the Company beginning on January 1, 2018.The Company is assessing the impact, if any, that the adoption of ASU 2016-15 may have on the Company’s consolidated financial statements. Income Taxes In October 2016, the FASB issued ASU 2016-16, “Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory.” This amendment is intended to improve accounting for the income tax consequences of intra-entity transfers of assets other than inventory. In accordance with this guidance, an entity should recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. The ASU is effective for the Company beginning on January 1, 2018 . Early adoption is permitted. The Company is assessing the impact, if any, that the adoption of ASU 2016-16 may have on the Company’s consolidated financial statements. Statement of Cash Flows: Restricted Cash In November 2016, the FASB issued ASU 2016-18, “Statement of Cash Flows (Topic 230): Restricted Cash, ” which provides amendments to current guidance to address the classifications and presentation of changes in restricted cash in the statement of cash flows. ASU 2016-18 will be effective for the Company beginning on January 1, 2018. Early adoption is permitted. The Company does not anticipate that the adoption of ASU 2016-18 will have a material impact on its consolidated financial statements. Business Combinations In January 2017, the FASB issued ASU 2017-01, “ Business Combinations (Topic 805): Clarifying the Definition of a Business,” which clarifies the definition of a business to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. ASU 2017-01 is effective for fiscal years beginning after December 15, 2017, including interim periods within that year. The amendments in ASU 2017-01 should be applied prospectively on or after the effective date. Early adoption is permitted. ASU 2017-01 will be effective for the Company beginning on January 1, 2018. The Company is assessing the impact, if any, that the adoption of ASU 2016-16 may have on the its consolidated financial statements. Accounting Changes and Error Corrections In January 2017, the FASB issued ASU No. 2017-03, “Accounting Changes and Error Corrections (Topic 250) and Investments – Equity Method and Joint Ventures (Topic 323): Amendments to SEC Paragraphs Pursuant to Staff Announcements at the September 22, 2016 and November 17, 2016 EITF Meetings.” The new guidance is intended to provide clarity in relation to the disclosure of the impact that ASU 2014-09 and ASU 2016-02 will have on our financial statements when adopted. The effective date for this guidance is the same as the effective date for ASU 2014-09 and ASU 2016-02. The Company is currently evaluating the effect that the adoption of ASU 2017-03 will have on its consolidated financial statements. Intangibles – Goodwill and Other In January 2017, the FASB issued ASU 2017-04, “Intangibles – Goodwill and Other (Topic 350) – Simplifying the Test for Goodwill Impairment,” which eliminates the second step from the goodwill impairment test and instead requires an entity to recognize a goodwill impairment charge for the amount by which the goodwill carrying amount exceeds the reporting unit’s fair value. The amendments in ASU 2017-04 are effective for public business entities for annual or interim goodwill impairment tests in annual periods beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company plans to early-adopt ASU 2017-04 effective January 1, 2017. As this standard is prospective in nature, the impact to our financial statements by not performing the second step to measure the amount of any potential goodwill impairment will depend on various factors. However, the elimination of the second step will reduce the complexity and cost of the subsequent measurement of goodwill.

Summary of Significant Accoun28

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Estimated Service Lives for Property and Equipment	The estimated service lives for property and equipment are as follows: Estimated Useful Life Furniture and fixtures 5 to 10 years Office equipment 2 to 7 years Transportation and service equipment 2 to 10 years Major equipment 2 to 10 years Tenant improvements 5 to 25 years Buildings 7 years

Acquisitions and Transactions (

Acquisitions and Transactions (Tables)	12 Months Ended
	Dec. 31, 2016
Schedule of Pro Forma Results of Acquisitions	Accordingly, such pro forma operating results were prepared for comparative purposes only and do not purport to be indicative of what would have occurred had the acquisitions been made as of January 1, 2015 or of results that may occur in the future. Year Ended December 31, (in thousands, except per share amounts) 2016 2015 2014 Total revenues $ 524,247 $ 522,347 $ 503,323 Net income attributable to the Company 3,547 13,703 16,773 Basic earnings per share 0.33 1.28 1.57 Diluted earnings per share 0.32 1.26 1.55
Restructuring Charges	From time to time, the Company’s management implements immaterial restructuring plans, including the closure or consolidation of certain sites as a result of the loss of certain customers. The impact of the charges resulting from restructuring plans are summarized below: Year Ended December 31, (in thousands) 2016 2015 2014 Cost of revenues, excluding depreciation and amortization $ 787 $ 900 $ 1,440 Selling, general and administrative expenses 275 175 1,162 Severance and related costs — 27 — Amortization expense — 225 — Other expense, net 573 — — Total restructuring charges $ 1,635 $ 1,327 $ 2,602
North Alabama Cancer Care Organization ('NACCO")
Summary of Recognized Amounts of Identifiable Assets Acquired and Liabilities Assumed	The following table summarizes the consideration paid for NACCO and the recognized amounts of identifiable assets acquired and liabilities assumed at the acquisition date : (in thousands) Consideration: Cash consideration paid $ 19,854 Working capital 735 Certain intangible assets and equipment transferred to NACCO by the Company 9,900 Total consideration $ 30,489 Recognized amounts of NACCO assets acquired and liabilities assumed: Cash received $ 1,630 Equipment, net 1,334 Goodwill 14,116 Identifiable intangible assets 50,500 Noncontrolling interest (37,091 ) Total consideration $ 30,489
Summary of Acquired Intangible Assets and Estimated Useful Lives	The following table summarizes the acquired intangible assets and their estimated useful lives at the acquisition date: (dollars in thousands) Estimated Useful Life (in years) Fair Value Identifiable intangible assets: Physician referral network 12 $ 26,500 Non-competition agreements 12 11,100 Trademarks 15 3,000 Certificates of need (“CONs”) N/A 9,900 $ 50,500
Summary of Key Assumptions Used in Valuation of Identifiable Intangible Assets	Specifically, key assumptions used in the valuation of the identifiable intangible assets, excluding CONs, consisted of the following: Discount rate 9.0 % Perpetual growth rate 1.0 % Tax rate 38.0 % Risk-free rate 4.0 % Peer company beta 0.69
Summary of Level 3 Estimates and Assumptions	Under the income and market approaches, the following Level 3 estimates and assumptions were used: Weighted Average Discount rate 16.3 % Perpetual growth rate 3.0 % Tax rate 39.2 % Risk-free rate 1.9 % EBITDA multiple 4.1x to 5.9x
American Health Centers, Inc. ("AHC")
Summary of Recognized Amounts of Identifiable Assets Acquired and Liabilities Assumed	The following table summarizes recognized amounts of identifiable assets acquired and liabilities assumed at the acquisition date: (in thousands) Equipment, net $ 2,354 Goodwill 335 Identifiable intangible assets 1,940 Total consideration $ 4,629
Summary of Acquired Intangible Assets and Estimated Useful Lives	The following table summarizes the acquired intangible assets and their estimated useful lives at the acquisition date: (dollars in thousands) Estimated Useful Life (in years) Fair Value Identifiable intangible assets: Customer contracts 15 $ 1,600 Non-competition agreement 5 340 $ 1,940
Pacific Cancer Institute Inc (PCI)
Summary of Recognized Amounts of Identifiable Assets Acquired and Liabilities Assumed	The following table summarizes recognized amounts of identifiable assets acquired and liabilities assumed at the acquisition date, as well as adjustments to finalize the valuations: (in thousands) Equipment, net $ 1,306 Other assets 152 Goodwill 6,505 Identifiable intangible assets 8,800 Deferred tax liability (3,748 ) Other liabilities (122 ) Noncontrolling interest (430 ) Total consideration $ 12,463
Summary of Acquired Intangible Assets and Estimated Useful Lives	The following table summarizes the acquired intangible assets and their estimated useful lives at the acquisition date, as well as adjustments to finalize the valuations: (dollars in thousands) Estimated Useful Life (in years) Fair Value Identifiable intangible assets: CONs N/A $ 6,200 Physician referral network 10 1,000 Trademarks 15 950 Non-solicitation and non-competition agreements 5 650 $ 8,800
AHIP Florida LLC
Summary of Recognized Amounts of Identifiable Assets Acquired and Liabilities Assumed	The following table summarizes recognized amounts of identifiable assets acquired and liabilities assumed at the acquisition date, as well as adjustments to net a working capital settlement and finalize valuations: (in thousands) Cash received $ 264 Equipment, net 890 Other assets 351 Goodwill 8,234 Identifiable intangible assets 15,600 Other liabilities (475 ) Noncontrolling interest (5,921 ) Total consideration $ 18,943
Summary of Acquired Intangible Assets and Estimated Useful Lives	The following table summarizes the acquired intangible assets and their estimated useful lives at the acquisition date: (dollars in thousands) Estimated Useful Life (in years) Fair Value Identifiable intangible assets: Physician referral network 20 $ 12,100 Trademarks 15 1,700 Non-solicitation and non-competition agreements 5 1,800 $ 15,600
Alliance HNI LLC
Summary of Consideration Paid and the Amounts of the Assets Acquired and Liabilities Assumed	The following table summarizes the consideration paid for AHNI and the recognized amounts of the assets acquired and liabilities assumed at the acquisition date: (in thousands) Consideration: The Company’s equity investment in AHNVPS transferred to AHNI $ 721 Certain equipment transferred to AHNI by the Company 477 Fair value of total consideration transferred 1,198 Fair value of the Company’s equity interest held in AHNI before the business combination 13,645 Recognized amounts of AHNI assets acquired and liabilities assumed: Cash 1,848 Accounts receivable, net 2,064 Equipment, net 6,962 Intangible assets 13,700 Other assets 1,919 Long term debt (4,110 ) Other liabilities (1,095 ) Total recognized net assets 21,288 Noncontrolling interest in AHNI 9,463 Goodwill $ 2,988
The Pain Center of Arizona
Summary of Recognized Amounts of Identifiable Assets Acquired and Liabilities Assumed	The following table summarizes recognized amounts of identifiable (in thousands) Cash received $ 234 Accounts receivable, net 4,440 Equipment, net 3,346 Other assets 416 Goodwill 22,566 Identifiable intangible assets 24,600 Debt (2,781 ) Other liabilities (3,030 ) Noncontrolling interest (20,598 ) Total consideration $ 29,193
Summary of Acquired Intangible Assets and Estimated Useful Lives	The following table summarizes the acquired intangible assets and their estimated useful lives at the acquisition date: (dollars in thousands) Estimated Useful Life (in years) Fair Value Identifiable intangible assets: Physician referral network 20 $ 13,500 Trademarks 20 11,100 $ 24,600

Share-Based Payment (Tables)

Share-Based Payment (Tables)	12 Months Ended
	Dec. 31, 2016
Share Based Compensation [Abstract]
Weighted Average Assumptions For Stock Option Awards	The following weighted average assumptions were used in the estimated grant date fair value calculations for stock option awards: Year Ended December 31, 2016 2015 2014 Risk free interest rate 1.53 % 1.65 % 1.83 % Expected dividend yield — % — % — % Expected stock price volatility 66.5 % 65.2 % 66.3 % Average expected life (in years) 6.0 6.0 6.0 Weighted average grant date fair value $ 4.32 $ 14.25 $ 17.56
Summary of Stock Option Activity	The following table summarizes the Company’s stock option activity: (dollars in thousands except per share amounts) Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (1) Outstanding at December 31, 2015 646,290 $ 19.91 Granted 200,388 $ 7.16 Exercised (121,667 ) $ 5.05 Canceled/forfeited (74,042 ) $ 22.08 Outstanding at December 31, 2016 650,969 $ 18.51 6.4 $ 917 Vested and expected to vest in the future at December 31, 2016 612,122 $ 19.23 6.2 $ 823 Vested and exercisable at December 31, 2016 463,165 $ 23.11 5.2 $ 462 (1) Represents the difference between the exercise price and the value of the Company’s stock at fiscal year-end.
Summary of Stock Options By Exercise Price Range	The following table summarizes information of the stock options outstanding and exercisable at December 31, 2016: Stock Options Outstanding Stock Options Exercisable Exercise Price Range Number of Shares Weighted Average Exercise Price Remaining Contractual Term (in years) Number of Shares Weighted Average Exercise Price Remaining Contractual Term (in years) $5.70 — $6.29 127,002 $ 5.96 5.0 127,002 $ 5.96 5.0 $6.30 — $6.93 145,804 $ 6.93 9.2 — $ — — $6.94 — $22.43 67,287 $ 9.79 8.1 25,287 $ 12.70 6.4 $22.44 — $28.46 67,609 $ 24.01 8.1 67,609 $ 24.01 8.1 $28.47 — $28.92 58,815 $ 28.61 4.6 58,815 $ 28.61 4.6 $28.93 — $30.27 102,952 $ 29.14 6.7 102,952 $ 29.14 6.7 $30.28 — $46.30 81,500 $ 40.72 1.3 81,500 $ 40.72 1.3 $5.70 — $46.30 650,969 $ 18.52 6.4 463,165 $ 23.11 5.2
Summary of Unvested Stock Option Activity	The following table summarizes the Company’s unvested stock option activity: (dollars in thousands except per share amounts) Number of Shares Weighted Average Grant Date Fair Value Aggregate Unrecognized Compensation (1) Weighted Average Period Over Which Expected to be Recognized (in years) Unvested at December 31, 2015 158,671 $ 15.01 Granted 200,388 $ 4.32 Vested (156,171 ) $ 15.05 Forfeited (15,084 ) $ 5.60 Unvested at December 31, 2016 187,804 $ 4.33 $ 476 2.2 (1) The valuation model applied in this calculation utilizes highly subjective assumptions that could potentially change over time, including the expected forfeiture rate and performance targets. Therefore, the amount of unrecognized share-based payment noted above does not necessarily represent the value that will ultimately be realized by the Company in the consolidated statements of income and comprehensive income.
Summary of Unvested RSU Activity	The following table summarizes the Company’s RSU activity: (dollars in thousands except per share amounts) Shares Weighted Average Grant Date Fair Value Aggregate Unrecognized Compensation Weighted Average Period Over Which Expected to be Recognized (in years) Unvested at December 31, 2015 74,413 9.18 Granted 175,441 8.30 Vested (74,413 ) 9.18 Forfeited (7,588 ) 6.93 Unvested at December 31, 2016 167,853 $ 8.37 $ 1,182 1.3
Summary of Share-based Compensation Expense	The impact of recording share-based compensation expense in the consolidated statements of income and comprehensive income is summarized below: Year Ended December 31, (in thousands) 2016 (1) 2015 2014 Share-based compensation expense (2) $ 3,176 $ 1,701 $ 1,515 Income tax benefit (936 ) (595 ) (540 ) Total share-based compensation expense after income taxes $ 2,240 $ 1,106 $ 975 (1) Includes Cash Right of $463. (2) Included in “Selling, general and administrative expenses” in the Company’s consolidated statement of income and comprehensive income.

Fair Value of Financial Instr31

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Summary of Valuation of Financial Instruments Reported at Fair Value on a Recurring Basis	The following table summarizes the valuation of the Company’s financial instruments that are reported at fair value on a recurring basis: Fair Value as of December 31, 2016 Fair Value as of December 31, 2015 (in thousands) Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Financial assets: Interest rate contracts - asset position $ 55 $ — $ 55 $ — $ — $ — $ — $ — Total financial assets $ 55 $ — $ 55 $ — $ — $ — $ — $ — Financial liabilities: Contingent consideration related to acquisitions $ 555 $ — $ — $ 555 $ 5,750 $ — $ — $ 5,750 Mandatorily redeemable noncontrolling interest 2,386 — — 2,386 2,386 — — 2,386 Interest rate contracts - liability position 53 — 53 — 86 — 86 — Total financial liabilities $ 2,994 $ — $ 53 $ 2,941 $ 8,222 $ — $ 86 $ 8,136 Financial instruments measured and recorded at fair value on a recurring basis were presented on the Company’s consolidated balance sheets as follows: Fair Value as of December 31, 2016 Fair Value as of December 31, 2015 (in thousands) Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Financial assets: Other assets $ 55 $ — $ 55 $ — $ — $ — $ — $ — Total financial assets $ 55 $ — $ 55 $ — $ — $ — $ — $ — Financial liabilities: Other accrued liabilities $ 2,994 $ — $ 53 $ 2,941 $ 8,139 $ — $ 3 $ 8,136 Other liabilities — — — — 83 — 83 — Total financial liabilities $ 2,994 $ — $ 53 $ 2,941 $ 8,222 $ — $ 86 $ 8,136
Schedule of Changes in Fair Value of Level 3 Liabilities	Changes in the fair value of the Company’s Level 3 liabilities were as follows: (in thousands) Contingent consideration related to acquisitions Mandatorily redeemable noncontrolling interest Balance at December 31, 2014 $ — $ — Additions (1) 5,750 2,386 Balance at December 31, 2015 5,750 2,386 Additions (1) 420 — Settlement of contingent consideration related to acquisitions (825 ) — Fair value adjustment (2) (4,790 ) — Balance at December 31, 2016 $ 555 $ 2,386 (1) See Note 3. (2) Adjustments to the estimated fair value of the contingent consideration are related to the actual versus expected performance of acquisitions and are included in “Other income, net” in the Company’s consolidated statement of income and comprehensive income.
Summary of Fair Values and Book Values of Long-term Debt	The following table summarizes the fair values and book values of the Company’s long-term debt: December 31, 2016 December 31, 2015 (in thousands) Fair Value Book Value Fair Value Book Value Variable-rate debt $ 526,475 $ 533,939 $ 538,520 $ 537,018 Fixed-rate debt 41,572 39,308 40,262 40,667 $ 568,047 $ 573,247 $ 578,782 $ 577,685

Impairment Charges (Tables)

Impairment Charges (Tables)	12 Months Ended
	Dec. 31, 2016
Certificates Of Need Related To Oncology Site In Alabama
Indefinite Lived Intangible Assets By Major Class [Line Items]
Summary of Key Assumptions Used in Valuation of Identifiable Intangible Assets	Under the income and market approaches, the following Level 3 estimates and assumptions were used: Discount rate 16.0% Perpetual growth rate 3.0% Tax rate 39.2% Risk-free rate 2.0% EBITDA multiple 4.0x to 6.0x

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill [Line Items]
Changes in the Carrying Amount of Goodwill	Changes in the carrying amount of goodwill are as follows: (in thousands) Radiology Oncology Interventional Total Balance at December 31, 2014 $ 42,166 $ 21,698 $ — $ 63,864 Goodwill acquired during the period 2,656 5,891 30,371 38,918 Balance at December 31, 2015 44,822 27,589 30,371 102,782 Goodwill acquired during the period 335 14,116 854 15,305 Adjustments to goodwill during the period — 615 428 1,043 Balance at December 31, 2016 $ 45,157 $ 42,320 $ 31,653 $ 119,130 Gross goodwill $ 199,499 $ 62,222 $ 31,653 $ 293,374 Accumulated impairment charges (154,342 ) (19,902 ) — (174,244 ) Balance at December 31, 2016 $ 45,157 $ 42,320 $ 31,653 $ 119,130
Components of Intangible Assets	Intangible assets consisted of the following: December 31, 2016 December 31, 2015 (dollars in thousands) Weighted Average Useful Life (in years) Gross Carrying Amount Accumulated Amortization Intangible Assets, net Gross Carrying Amount Accumulated Amortization Intangible Assets, net Finite-lived intangible assets: Customer contracts 16 $ 230,323 $ (101,240 ) $ 129,083 $ 186,316 $ (92,280 ) $ 94,036 Other 18 41,820 (22,141 ) 19,679 38,522 (20,540 ) 17,982 Total amortizing intangible assets 16 $ 272,143 $ (123,381 ) $ 148,762 $ 224,838 $ (112,820 ) $ 112,018 Indefinite-lived intangible assets 50,215 50,905 Total other intangible assets $ 198,977 $ 162,923
Estimated Annual Amortization Expense	Amortization expense for finite-lived intangible assets is reported as “Amortization expense” in the consolidated statements of income and comprehensive income. Estimated annual amortization expense for each of the fiscal years ending December 31, is presented below: (in thousands) 2017 $ 13,062 2018 12,689 2019 12,200 2020 11,710 2021 10,802 Thereafter 88,299 Total expected amortization expense $ 148,762
Goodwill
Goodwill [Line Items]
Summary of Key Assumptions Used in Valuation of Identifiable Intangible Assets	Specifically, the Company utilized the following Level 3 estimates and assumptions in its analyses: October 1, 2016 October 1, 2015 Discount rate 10.0% to 13.0% 10.0% to 15.0% Perpetual growth rate 1.0% to 3.0% 2.5% Tax rate 40.0% 40.0% Risk-free rate 4.0% 2.5% Peer company beta 0.5 to 0.6 0.8 to 1.2 Revenue multiple 1.0x to 1.35x 1.0x to 1.5x EBITDA multiple 5.5x 5.5x to 6.0x

Supplemental Balance Sheet In34

Supplemental Balance Sheet Information (Tables)	12 Months Ended
	Dec. 31, 2016
Supplemental Balance Sheet Information [Abstract]
Plant, Property and Equipment, Net	Plant, property and equipment, net as of December 31, 2016 are as follows: (in thousands) Cost Accumulated Depreciation Net Carrying Amount Furniture and fixtures $ 4,905 $ (4,231 ) $ 674 Office equipment 80,384 (57,295 ) 23,089 Transportation and service equipment 16,140 (4,291 ) 11,849 Major equipment 794,153 (639,452 ) 154,701 Tenant improvements 43,888 (29,665 ) 14,223 Buildings and land 340 (62 ) 278 Total $ 939,810 $ (734,996 ) $ 204,814 Plant, property and equipment, net as of December 31, 2015 are as follows: (in thousands) Cost Accumulated Depreciation Net Carrying Amount Furniture and fixtures $ 4,825 $ (3,977 ) $ 848 Office equipment 71,245 (49,981 ) 21,264 Transportation and service equipment 5,884 (3,306 ) 2,578 Major equipment 758,718 (623,429 ) 135,289 Tenant improvements 42,792 (25,904 ) 16,888 Buildings and land 340 (19 ) 321 Total $ 883,804 $ (706,616 ) $ 177,188
Components of Other Accrued Liabilities	Other accrued liabilities consisted of the following: (in thousands) December 31, 2016 December 31, 2015 Systems rental and maintenance costs $ 1,064 $ 1,808 Site rental fees 899 1,121 Property and sales taxes payable 7,254 8,695 Self-insurance expense 2,612 2,037 Legal fees 1,537 1,971 Deferred gain on sale of equipment 87 312 Equipment purchases 848 4,756 Customer overpayments 2,555 1,580 Contingent consideration related to acquisition 555 5,750 Mandatorily redeemable noncontrolling interest 2,386 2,386 Other expenses 9,526 6,037 Total $ 29,323 $ 36,453

Long-Term Debt and Senior Sub35

Long-Term Debt and Senior Subordinated Credit Facility (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Components of Long-term Debt	Long-term debt consisted of the following: (in thousands) December 31, 2016 December 31, 2015 Term loan facility $ 497,674 $ 502,874 Discount on term loan facility (1,310 ) (1,823 ) Revolving loan facility 21,500 19,500 Equipment under capital leases 16,040 13,006 Equipment debt 39,343 44,128 Deferred financing costs, net (24,502 ) (6,594 ) Long-term debt, including current portion 548,745 571,091 Less current portion 20,652 20,406 Long-term debt $ 528,093 $ 550,685
Schedule of Principal Maturities of Long-term Debt	The annual principal maturities of long-term debt as of December 31, 2016 are as follows: Bank Credit Facilities (in thousands) Term Loan Revolving Credit Facility Equipment Under Capital Leases Equipment Loans Total Year ending December 31: 2017 $ 5,200 $ — $ 4,074 $ 12,628 $ 21,902 2018 5,200 21,500 4,065 10,086 40,851 2019 487,274 — 4,019 8,547 499,840 2020 — — 4,801 6,166 10,967 2021 — — 843 1,916 2,759 Total principal maturities, including imputed interest on equipment under capital leases $ 497,674 $ 21,500 $ 17,802 $ 39,343 $ 576,319 Less: imputed interest on equipment under capital leases (1,762 ) (1,762 ) Total principal maturities, excluding imputed interest on equipment under capital leases $ 16,040 $ 574,557

Income Per Common Share (Tables

Income Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Computation of Basic and Diluted Income Per Share	The following table sets forth the computation of basic and diluted income per share: Year Ended December 31, (in thousands except per share amounts) 2016 2015 2014 Numerator: Net income attributable to Alliance HealthCare Services, Inc. $ 493 $ 6,742 $ 10,618 Denominator: Weighted average shares-basic 10,866 10,741 10,669 Effect of dilutive securities: Stock options and RSUs 93 108 167 Weighted average shares-diluted 10,959 10,849 10,836 Income per common share attributable to Alliance HealthCare Services, Inc.: Basic $ 0.05 $ 0.63 $ 1.00 Diluted $ 0.04 $ 0.62 $ 0.98 Stock options excluded from the computation of diluted per share amounts: Weighted average shares for which the exercise price exceeds average market price of common stock 397 384 337 Average exercise price per share that exceeds average market price of common stock $ 27.56 $ 30.16 $ 34.75

Derivatives (Tables)

Derivatives (Tables)	12 Months Ended
	Dec. 31, 2016
Summary Of Derivative Instruments [Abstract]
Summary of Interest Rate Cash Flow Hedges	The Company’s interest rate cash flow hedges consisted of the following as of December 31, 2016: Fair Value Asset (Liability) (1) (dollars in thousands) Notional Amount Fixed Payment Rate Maturity Date December 31, 2016 December 31, 2015 Liability Derivatives Derivatives designated as cash flow hedging instruments: One-month LIBOR plus 2.50% interest rate swap, effective December 2012 $ 1,119 3.75% December 2017 $ (3 ) $ (11 ) One-month LIBOR plus 2.00% interest rate swap, effective March 2013 1,172 2.87% April 2018 — (2 ) One-month LIBOR interest rate swap, effective December 2014 1,003 1.34% November 2019 (2 ) (7 ) One-month LIBOR plus 2.00% interest rate swap, effective December 2015 4,663 3.69% December 2021 (24 ) (54 ) One-month LIBOR interest rate swap, effective December 2015 1,169 1.37% December 2020 — (5 ) One-month LIBOR interest rate swap, effective September 2016 4,438 1.17% September 2021 33 — Derivatives not designated as cash flow hedging instruments: One-month LIBOR interest rate swap (2) 1,958 0.75% - 1.68% April 2017 - April 2020 (2 ) (7 ) Total liability derivatives $ 15,522 $ 2 $ (86 ) (1) The fair values of the interest rate swap assets and liabilities are included in “Other assets” and “Other accrued liabilities,” respectively, in the consolidated balance sheets. (2) The Company acquired eight non-designated interest rate swaps (the “AHNI Swaps”) as a result of the step acquisition of AHNI. The changes in fair market value of the AHNI Swaps are recorded in “Interest expense, net” as incurred.
Effect of Designated Derivative Instruments on the Consolidated Statements of Income and Comprehensive Income	The following tables summarize the effect of derivative instruments for the periods indicated and the line items in the accompanying consolidated statements of income and comprehensive income where the results are recorded for cash flow hedges: Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Loss Reclassified from Accumulated OCI Amount of Loss Reclassified from Accumulated OCI into Income (Effective Portion) Location of (Loss) Gain Recognized in Amount of Gain Recognized in Income on Derivatives Income (Ineffective Portion) Year Ended December 31, into Income Year Ended December 31, Income on Derivatives Year Ended December 31, (in thousands) 2016 2015 (Effective Portion) 2016 2015 (Ineffective Portion) 2016 2015 Interest rate contracts $ 104 $ (246 ) Interest expense, net $ 417 $ 25 Interest expense, net $ — $ 1 Total $ 104 $ (246 ) $ 417 $ 25 $ — $ 1

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments And Contingencies Disclosure [Abstract]
Schedule of Future Minimum Operating Lease Payments	The future minimum payments under operating leases are as follows: (in thousands) Year ending December 31: 2017 $ 15,715 2018 13,872 2019 7,761 2020 6,559 2021 5,590 Thereafter 37,810 $ 87,307

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Components of Income Tax Expense	The income tax expense shown in the consolidated statements of income and comprehensive income consists of the following: Year Ended December 31, (in thousands) 2016 2015 2014 Current: Federal $ 85 $ (91 ) $ 239 State 264 288 334 Total current 349 197 573 Deferred: Federal 2,030 5,864 5,858 State 473 475 896 Total deferred 2,503 6,339 6,754 Total income tax expense $ 2,852 $ 6,536 $ 7,327
Significant Components of Net Deferred Tax Liabilities	Significant components of the Company’s net deferred tax liabilities are as follows: (in thousands) December 31, 2016 December 31, 2015 Basis differences in equipment $ (31,376 ) $ (24,162 ) Basis differences associated with acquired investments (24,467 ) (21,612 ) Basis differences in intangible assets (1,448 ) (287 ) Net operating losses 19,812 6,841 Accounts receivable 1,303 1,673 State income taxes 685 992 Accruals not currently deductible for income tax purposes 8,372 7,913 Deferred financing costs (4,391 ) — Other 5,692 5,622 Total deferred taxes (25,818 ) (23,020 ) Valuation allowance — — Net deferred taxes $ (25,818 ) $ (23,020 )
Reconciliation of Expected Total Income Tax Expense	A reconciliation of expected total income tax expense, computed using the federal statutory rate on income is as follows: Year Ended December 31, (in thousands) 2016 2015 2014 U.S. federal tax benefit at statutory rates $ 6,664 $ 10,591 $ 9,861 State income taxes, net of federal benefit 479 496 800 Earnings from unconsolidated investees 451 1,187 1,629 Noncontrolling interest (5,945 ) (7,130 ) (5,209 ) Shareholder transaction costs 715 737 — Section 162(m) excess compensation 805 — — Changes in fair value of contingent consideration related to acquisition (508 ) — — Other 191 655 246 Income tax expense $ 2,852 $ 6,536 $ 7,327
Reconciliation of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows: (in thousands) 2016 2015 2014 Unrecognized tax benefits at January 1 $ 229 $ 269 $ 287 Increases for positions taken in current year 97 51 64 Increases for positions taken in a prior year 5 — 31 Decreases for positions taken in a prior year (9 ) (11 ) — Decreases for lapses in the applicable statute of limitations (50 ) (80 ) (113 ) Decreases for settlements with taxing authorities — — — Unrecognized tax benefits at December 31 $ 272 $ 229 $ 269

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Summary of Revenue and Reimbursed Expenses with Unconsolidated Equity Investees	The following table summarizes revenues from management agreements with unconsolidated equity investees: Year ended December 31, (in thousands) 2016 2015 2014 Revenue from management agreements $ 1,473 $ 6,099 $ 9,134 The following table summarizes the revenue and reimbursed expenses related to the Company’s unconsolidated equity investees: Year ended December 31, (in thousands) 2016 2015 2014 Revenue and reimbursed expenses $ 1,013 $ 4,879 $ 7,320

Investments in Unconsolidated41

Investments in Unconsolidated Investees (Tables)	12 Months Ended
	Dec. 31, 2016
Equity Method Investments And Joint Ventures [Abstract]
Schedule of Financial Data of Unconsolidated Investees, Balance Sheet Data	Set forth below are certain balance sheet and operating results for the aggregate of the Company’s unconsolidated investees. The operating results for AHNI from January 1, 2015 through its acquisition on August 1, 2015 are included in the results for the year ended December 31, 2015: (in thousands) December 31, 2016 December 31, 2015 Balance sheet data: Current assets $ 2,860 $ 2,644 Noncurrent assets 111 273 Current liabilities 760 676 Noncurrent liabilities 32 35
Schedule of Financial Data of Unconsolidated Investees, Combined Operating Results	Year Ended December 31, (in thousands) 2016 2015 2014 Combined operating results: Revenues $ 10,389 $ 20,796 $ 27,735 Expenses 3,055 9,038 13,597 Net income 7,333 11,758 14,138 Earnings from unconsolidated investees 1,290 3,391 4,654

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Summary of Revenue By Segment	The following table summarizes the Company’s revenue by segment: Year Ended December 31, (in thousands) 2016 2015 2014 Revenue: MRI $ 197,316 $ 183,893 $ 180,815 PET/CT 126,927 128,356 133,224 Other radiology 26,556 27,378 29,424 Radiology 350,799 339,627 343,463 Oncology 107,220 99,957 92,924 Interventional 45,562 33,193 — Corporate / Other 1,968 277 — Total $ 505,549 $ 473,054 $ 436,387
Summary of Adjusted EBITDA By Segment	The following table summarizes the Company’s Adjusted EBITDA: Year Ended December 31, (in thousands) 2016 2015 2014 Adjusted EBITDA (1) Radiology $ 96,828 $ 94,475 $ 104,681 Oncology 46,609 43,112 41,846 Interventional 3,935 5,175 — Corporate / Other (15,904 ) (11,502 ) (10,772 ) Total $ 131,468 $ 131,260 $ 135,755 (1) Adjusted EBITDA by segment includes inter-segment operating expense allocations from Corporate / Other to Radiology and Oncology of $18.9 million and $6.0 million, respectively, in 2016, $18.9 million and $6.4 million, respectively, in 2015, and $20.9 million and $4.9 million, respectively, in 2014.
Reconciliation of Income Before Income Taxes, Earnings From Unconsolidated Investees, and Noncontrolling Interest to Total Adjusted EBITDA	The reconciliation of income before income taxes, earnings from unconsolidated investees, and noncontrolling interest to total Adjusted EBITDA is shown below: Year Ended December 31, (in thousands) 2016 2015 2014 Income before income taxes, earnings from unconsolidated investees, and noncontrolling interest $ 19,040 $ 30,260 $ 28,174 Earnings from unconsolidated investees 1,290 3,391 4,654 Interest expense, net 34,506 26,241 24,693 Depreciation expense 54,972 48,595 54,971 Amortization expense 10,561 9,325 7,880 Share-based payment (included in “ expenses ” 3,176 1,701 1,515 Severance and related costs 3,910 1,347 2,517 Restructuring charges (Note 3) 1,635 1,327 2,602 Transaction costs 1,886 3,296 2,344 Shareholder transaction costs 4,219 1,853 — Impairment charges 632 6,817 308 Legal matters expense, net 106 6,915 5,587 Changes in fair value of contingent consideration related to acquisitions (included in “Other income, net”) (4,790 ) — — Non-cash gain on step acquisition (included in “Other income, net”) — (10,672 ) — Other non-cash charges (included in “Other income, net”) 325 864 510 Total Adjusted EBITDA $ 131,468 $ 131,260 $ 135,755
Summary of Identifiable Assets By Segment	The following table summarizes the Company’s identifiable assets by segment: As of December 31, (in thousands) 2016 2015 2014 Identifiable assets: Radiology $ 301,137 $ 280,497 $ 211,004 Oncology 256,456 213,698 182,880 Interventional 82,221 83,480 — Corporate / Other 20,050 25,985 63,911 Total $ 659,864 $ 603,660 $ 457,795
Summary of Capital Expenditures By Segment	The following table summarizes the Company’s equipment capital expenditures by segment: As of December 31, (in thousands) 2016 2015 2014 Capital expenditures: Radiology $ 50,511 $ 27,478 $ 18,311 Oncology 3,043 21,694 3,994 Interventional 155 1,287 — Corporate / Other 2,692 5,052 10,081 Total $ 56,401 $ 55,511 $ 32,386

Quarterly Financial Data (Table

Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data	The following table sets forth selected unaudited quarterly information for the Company’s last eight fiscal quarters derived from the Company’s interim financial statements. Such financial statements have been prepared on the same basis as the consolidated financial statements and all necessary adjustments (which consisted only of normal recurring adjustments) have been included to present fairly the results of such periods when read in conjunction with the consolidated financial statements and related notes included elsewhere herein. Quarter Ended Mar. 31, Jun. 30, Sep. 30, Dec. 31, (in thousands except per share amounts) 2016 2016 2016 2016 Revenues $ 123,725 $ 125,317 $ 127,121 $ 129,386 Cost of revenues, excluding depreciation and amortization 70,914 69,939 71,132 73,761 Income before income taxes, earnings from unconsolidated investees and noncontrolling interest 2,205 8,016 7,407 1,412 Net income 3,402 6,188 5,827 2,061 Net (loss) income attributable to Alliance HealthCare Services, Inc. (1,190 ) 2,459 1,358 (2,134 ) (Loss) income per common share attributable to Alliance HealthCare Services, Inc.: Basic $ (0.11 ) $ 0.23 $ 0.12 $ (0.20 ) Diluted $ (0.11 ) $ 0.23 $ 0.12 $ (0.20 ) Quarter Ended Mar. 31, Jun. 30, Sep. 30, Dec. 31, (in thousands except per share amounts) 2015 2015 2015 2015 Revenues $ 109,429 $ 118,504 $ 120,784 $ 124,337 Cost of revenues, excluding depreciation and amortization 61,886 67,485 67,057 72,676 Income before income taxes, earnings from unconsolidated investees and noncontrolling interest 6,507 284 17,571 5,898 Net income 6,098 2,942 13,065 5,010 Net income (loss) attributable to Alliance HealthCare Services, Inc. 1,751 (1,961 ) 7,204 (252 ) Income (loss) per common share attributable to Alliance HealthCare Services, Inc.: Basic $ 0.16 $ (0.18 ) $ 0.67 $ (0.02 ) Diluted $ 0.16 $ (0.18 ) $ 0.67 $ (0.02 )

Description of the Company an44

Description of the Company and Basis of Financial Statement Presentation - Additional Information (Details)	12 Months Ended
	Dec. 31, 2016EmployeeSystemcenterHospitalOrHealthcarePartnerstate
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Number of diagnostic imaging and radiation therapy systems | System	625
Number of fixed-site imaging centers	113
Number of radiation therapy centers and SRS facilities	33
Number of hospitals and healthcare providers for which the Company provides quality healthcare services | HospitalOrHealthcarePartner	1,100
Number of states in which the Company operates | state	46
Number of team members committed to providing exceptional patient care and exceeding customer expectations | Employee	2,450
Place of incorporation	Delaware
Date of incorporation	May 27, 1987

Summary of Significant Accoun45

Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2016USD ($)Customersegment	Dec. 31, 2015USD ($)Customersegment	Dec. 31, 2014USD ($)
Accounting Policies [Line Items]
Cash equivalents, original maturity	three months or less
Cash and cash equivalents in excess of federally insured limits	$ 15,400,000	$ 29,500,000
Number of operating segments | segment	3	2
Workers compensation and auto insurance, deductible	$ 250,000
General and professional insurance, deductible	100,000
Advertising expense	$ 2,000,000	$ 1,300,000	$ 1,400,000
Accounting Standards Update 2015-03 | Offset Long Term Debt
Accounting Policies [Line Items]
Impact of reclassification due to adoption of new accounting pronouncement		6,600,000
Accounting Standards Update 2015-03 | Deferred Financing Costs Net
Accounting Policies [Line Items]
Impact of reclassification due to adoption of new accounting pronouncement		(6,600,000)
Accounting Standards Update 2015-17 | Long Term Deferred Tax Liabilities
Accounting Policies [Line Items]
Impact of reclassification due to adoption of new accounting pronouncement		6,500,000
Accounting Standards Update 2015-17 | Deferred Tax Assets
Accounting Policies [Line Items]
Impact of reclassification due to adoption of new accounting pronouncement		$ (6,500,000)
Equipment | Minimum
Accounting Policies [Line Items]
Equipment residual value as a percent of original equipment cost	5.00%
Equipment salvage value estimated useful lives (years)	1 year
Equipment | Maximum
Accounting Policies [Line Items]
Equipment residual value as a percent of original equipment cost	10.00%
Equipment salvage value estimated useful lives (years)	2 years
Customer Concentration Risk | Accounts Receivable
Accounting Policies [Line Items]
Number of customers for which minimum percentage threshold is met | Customer	0	0
Minimum percentage threshold for individual customer requiring disclosure	10.00%	10.00%
Customer Concentration Risk | Sales Revenue, Net
Accounting Policies [Line Items]
Minimum percentage threshold for individual customer requiring disclosure	10.00%	10.00%	10.00%
Provision For Doubtful Accounts Concentration Risk | Sales Revenue, Net
Accounting Policies [Line Items]
Concentration risk, percentage	0.40%	0.60%	0.60%
Revenue From Third Party Payers And Patients Concentration Risk | Sales Revenue, Net
Accounting Policies [Line Items]
Concentration risk, percentage	25.00%	20.00%	20.00%
Revenue From Management Fees Concentration Risk | Sales Revenue, Net
Accounting Policies [Line Items]
Concentration risk, percentage	0.50%	2.00%	2.00%

Summary of Significant Accoun46

Summary of Significant Accounting Policies - Summary of Estimated Service Lives for Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2016
Furniture and fixtures | Minimum
Accounting Policies [Line Items]
Estimated Useful Life	5 years
Furniture and fixtures | Maximum
Accounting Policies [Line Items]
Estimated Useful Life	10 years
Office equipment | Minimum
Accounting Policies [Line Items]
Estimated Useful Life	2 years
Office equipment | Maximum
Accounting Policies [Line Items]
Estimated Useful Life	7 years
Transportation and service equipment | Minimum
Accounting Policies [Line Items]
Estimated Useful Life	2 years
Transportation and service equipment | Maximum
Accounting Policies [Line Items]
Estimated Useful Life	10 years
Major equipment | Minimum
Accounting Policies [Line Items]
Estimated Useful Life	2 years
Major equipment | Maximum
Accounting Policies [Line Items]
Estimated Useful Life	10 years
Tenant improvements | Minimum
Accounting Policies [Line Items]
Estimated Useful Life	5 years
Tenant improvements | Maximum
Accounting Policies [Line Items]
Estimated Useful Life	25 years
Buildings
Accounting Policies [Line Items]
Estimated Useful Life	7 years

Acquisitions and Transactions -

Acquisitions and Transactions - Additional Information (Details)	Nov. 01, 2016USD ($)	May 19, 2016USD ($)SitePart	Dec. 31, 2015USD ($)	Oct. 14, 2015USD ($)Location	Sep. 16, 2015USD ($)$ / sharesshares	Aug. 01, 2015	Feb. 17, 2015USD ($)Location	Nov. 30, 2014USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 12, 2016$ / shares	Jul. 31, 2015
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Payments to acquire businesses, net of cash									$ 25,912,000	$ 49,140,000	$ 16,043,000
Transaction and other integration costs									1,886,000	3,296,000	2,344,000
Net revenue generated from acquisitions									8,700,000	43,800,000
Contingent consideration related to acquisition			$ 5,750,000						555,000	5,750,000
Purchase price adjustment - increase to goodwill									1,043,000
Mandatorily redeemable noncontrolling interest			2,386,000						2,386,000	2,386,000
Non-cash gain on step acquisition									0	10,672,000	0
Settlement of contingent consideration related to acquisitions									825,000	0	0
Goodwill			102,782,000						119,130,000	$ 102,782,000	63,864,000
Alliance-HNV PET/CT Services, LLC (AHNVPS)
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Equity interest in acquiree, percentage													46.60%
North Alabama Cancer Care Organization ('NACCO")
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Payments to acquire businesses, net of cash	$ 19,854,000
Net revenue generated from acquisitions									4,000,000
Ownership interest, percentage acquired	45.10%
Goodwill and intangible assets tax amortization period	15 years
Net income (loss) before income taxes generated from acquisition									1,100,000
Noncontrolling interest, fair value	$ 37,091,000
Cash acquired	1,630,000
Goodwill	$ 14,116,000
American Health Centers, Inc. ("AHC")
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Payments to acquire businesses, net of cash		$ 4,200,000
Net revenue generated from acquisitions									2,500,000
Goodwill and intangible assets tax amortization period		15 years
Net income (loss) before income taxes generated from acquisition									$ 1,000,000
Sites acquired, effective date									May 19, 2016
Number of parts in transaction to acquire business | Part		2
Contingent consideration performance period (in months)		18 months
Contingent consideration related to acquisition		$ 420,000							$ 405,000
Goodwill		$ 335,000
American Health Centers, Inc. ("AHC") | New Hampshire And Vermont Mobile Radiology Sites
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Number of sites acquired | Site		8
American Health Centers, Inc. ("AHC") | New Hampshire And Vermont Mobile Nuclear Medicine Sites.
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Number of sites acquired | Site		5
Pacific Cancer Institute Inc (PCI)
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Payments to acquire businesses, net of cash			$ 11,000,000
Ownership interest, percentage acquired			95.00%							95.00%
Goodwill and intangible assets tax amortization period										15 years
Contingent consideration performance period (in months)										12 months
Contingent consideration related to acquisition			$ 1,400,000						0	$ 1,400,000
Purchase price adjustment - decrease to acquired equipment									615,000
Purchase price adjustment - increase to goodwill									615,000
Noncontrolling interest, fair value			430,000							430,000
Goodwill			$ 6,505,000							6,505,000
AHIP Florida LLC
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Payments to acquire businesses, net of cash				$ 15,000,000
Net revenue generated from acquisitions										3,100,000
Ownership interest, percentage acquired				60.00%
Goodwill and intangible assets tax amortization period				15 years
Net income (loss) before income taxes generated from acquisition										357,000
Contingent consideration performance period (in months)				12 months
Contingent consideration related to acquisition				$ 2,500,000					0
Purchase price adjustment - increase to goodwill									428,000
Noncontrolling interest, fair value				$ 5,921,000
Number of locations operated by entity | Location				8
Cash acquired				$ 264,000
Percentage of noncontrolling interest allowed to sell to the Company				10.00%
Purchase price adjustment - decrease to total consideration									387,000
Purchase price adjustment - decrease to other assets									833,000
Purchase price adjustment - increase to identifiable intangible assets									200,000
Purchase price adjustment - increase to noncontrolling interest									182,000
Mandatorily redeemable noncontrolling interest				$ 2,386,000					2,386,000
Goodwill				$ 8,234,000
Alliance HNI LLC
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Net revenue generated from acquisitions										10,600,000
Net income (loss) before income taxes generated from acquisition										5,900,000
Ownership interest before step acquisition, percentage						50.00%
Additional ownership interest acquired, percentage						15.50%
Ownership interest after step acquisition, percentage						65.50%
Useful life of acquired intangible assets						15 years
Weighted average cost of capital						11.50%
Revenue multiple						1.7
Non-cash gain on step acquisition										10,672,000
Alliance HNI LLC | Minimum
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
EBITDA multiple						5
Alliance HNI LLC | Maximum
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
EBITDA multiple						6.5
Alliance-HNI Leasing Co (AHNIL) | Alliance HNI LLC
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Equity interest in acquiree, percentage													98.00%
Alliance-HNV PET/CT Services, LLC (AHNVPS) Not Consolidate | Alliance HNI LLC
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Equity interest in acquiree, percentage													53.40%
The Pain Center of Arizona
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Payments to acquire businesses, net of cash							$ 24,100,000
Net revenue generated from acquisitions										30,100,000
Ownership interest, percentage acquired							59.00%
Goodwill and intangible assets tax amortization period							15 years
Net income (loss) before income taxes generated from acquisition										$ 1,800,000
Contingent consideration performance period (in months)							12 months
Contingent consideration related to acquisition							$ 1,800,000
Noncontrolling interest, fair value							$ 20,598,000
Number of locations operated by entity | Location							12
Cash acquired							$ 234,000
Notes receivable extinguishment, related parties							3,100,000
Settlement of contingent consideration related to acquisitions									$ 810,000
Goodwill							$ 22,566,000
CAMC Cancer Center
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Net revenue generated from acquisitions											1,800,000
Ownership interest, percentage acquired								50.00%
Net income (loss) before income taxes generated from acquisition											$ 899,000
Payments to acquire interest in joint venture								$ 14,400,000
Goodwill								6,900,000
Intangible assets								21,700,000
CAMC Cancer Center | Certificates of Need
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Intangible assets								$ 11,500,000
Tahoe Oaktree M T S And Larry C Buckelew
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Percentage of fees and expenses incurred by the Company in connection with the credit agreement that are attributable to Tahoe and Selling Stockholders					100.00%
Threshold above which reasonable and documented fees and expenses are attributable to Tahoe and Selling Stockholders					$ 1,000,000
Oaktree M T S And Larry C Buckelew
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Capital contributions					15,300,000
Capital contributions, taxes					$ 213,000
Tahoe Investment Group Co Ltd
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Number of shares acquired from Selling Stockholders | shares					5,537,945
Consideration transferred					$ 102,500,000
Stock price per share | $ / shares					$ 18.50
Issuance of cash-based awards under management incentive agreement					$ 1,500,000
Capital contributions					$ 13,500,000
Ownership interest, percentage acquired									52.00%
Tahoe Investment Group Co Ltd | Common Shares
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Proposed purchase price | $ / shares												$ 9.60

Acquisitions and Transactions48

Acquisitions and Transactions - Recognized Identifiable Assets and Liabilities (Details) - USD ($)	Nov. 01, 2016	Dec. 31, 2016	May 19, 2016	Dec. 31, 2015	Oct. 14, 2015	Feb. 17, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$ 119,130,000		$ 102,782,000			$ 63,864,000
North Alabama Cancer Care Organization ('NACCO")
Business Acquisition [Line Items]
Cash consideration paid	$ 19,854,000
Working capital	735,000
Certain intangible assets and equipment transferred to NACCO by the Company	9,900,000
Total consideration	30,489,000
Cash received	1,630,000
Equipment, net	1,334,000
Goodwill	14,116,000
Identifiable intangible assets	50,500,000
Noncontrolling interest	(37,091,000)
Total consideration	$ 30,489,000
American Health Centers, Inc. ("AHC")
Business Acquisition [Line Items]
Equipment, net			$ 2,354,000
Goodwill			335,000
Identifiable intangible assets			1,940,000
Total consideration			$ 4,629,000
Pacific Cancer Institute Inc (PCI)
Business Acquisition [Line Items]
Equipment, net				1,306,000
Other assets				152,000
Goodwill				6,505,000
Identifiable intangible assets				8,800,000
Deferred tax liability				(3,748,000)
Other liabilities				(122,000)
Noncontrolling interest				(430,000)
Total consideration				$ 12,463,000
AHIP Florida LLC
Business Acquisition [Line Items]
Cash received					$ 264,000
Equipment, net					890,000
Other assets					351,000
Goodwill					8,234,000
Identifiable intangible assets					15,600,000
Other liabilities					(475,000)
Noncontrolling interest					(5,921,000)
Total consideration					$ 18,943,000
The Pain Center of Arizona
Business Acquisition [Line Items]
Cash received						$ 234,000
Accounts receivable, net						4,440,000
Equipment, net						3,346,000
Other assets						416,000
Goodwill						22,566,000
Identifiable intangible assets						24,600,000
Debt						(2,781,000)
Other liabilities						(3,030,000)
Noncontrolling interest						(20,598,000)
Total consideration						$ 29,193,000

Acquisitions and Transactions49

Acquisitions and Transactions - Summary of Acquired Intangible Assets and Estimated Useful Lives (Details) - USD ($) $ in Thousands	Nov. 01, 2016	May 19, 2016	Oct. 14, 2015	Feb. 17, 2015	Dec. 31, 2015
North Alabama Cancer Care Organization ('NACCO")
Business Acquisition [Line Items]
Identifiable intangible assets, Fair Value	$ 50,500
American Health Centers, Inc. ("AHC")
Business Acquisition [Line Items]
Identifiable intangible assets, Fair Value		$ 1,940
Pacific Cancer Institute Inc (PCI)
Business Acquisition [Line Items]
Identifiable intangible assets, Fair Value					$ 8,800
AHIP Florida LLC
Business Acquisition [Line Items]
Identifiable intangible assets, Fair Value			$ 15,600
The Pain Center of Arizona
Business Acquisition [Line Items]
Identifiable intangible assets, Fair Value				$ 24,600
Certificates of Need (“CONs”) | North Alabama Cancer Care Organization ('NACCO")
Business Acquisition [Line Items]
Identifiable intangible assets, Fair Value	$ 9,900
Certificates of Need (“CONs”) | Pacific Cancer Institute Inc (PCI)
Business Acquisition [Line Items]
Identifiable intangible assets, Fair Value					$ 6,200
Physician Referral Network | North Alabama Cancer Care Organization ('NACCO")
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)	12 years
Identifiable intangible assets, Fair Value	$ 26,500
Physician Referral Network | Pacific Cancer Institute Inc (PCI)
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)					10 years
Identifiable intangible assets, Fair Value					$ 1,000
Physician Referral Network | AHIP Florida LLC
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)			20 years
Identifiable intangible assets, Fair Value			$ 12,100
Physician Referral Network | The Pain Center of Arizona
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)				20 years
Identifiable intangible assets, Fair Value				$ 13,500
Non-Competition Agreements | North Alabama Cancer Care Organization ('NACCO")
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)	12 years
Identifiable intangible assets, Fair Value	$ 11,100
Non-Competition Agreements | American Health Centers, Inc. ("AHC")
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)		5 years
Identifiable intangible assets, Fair Value		$ 340
Trademarks | North Alabama Cancer Care Organization ('NACCO")
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)	15 years
Identifiable intangible assets, Fair Value	$ 3,000
Trademarks | Pacific Cancer Institute Inc (PCI)
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)					15 years
Identifiable intangible assets, Fair Value					$ 950
Trademarks | AHIP Florida LLC
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)			15 years
Identifiable intangible assets, Fair Value			$ 1,700
Trademarks | The Pain Center of Arizona
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)				20 years
Identifiable intangible assets, Fair Value				$ 11,100
Customer Contracts | American Health Centers, Inc. ("AHC")
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)		15 years
Identifiable intangible assets, Fair Value		$ 1,600
Non-Solicitation and Non-Competition Agreements | Pacific Cancer Institute Inc (PCI)
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)					5 years
Identifiable intangible assets, Fair Value					$ 650
Non-Solicitation and Non-Competition Agreements | AHIP Florida LLC
Business Acquisition [Line Items]
Identifiable intangible assets, Estimated Useful Life (in years)			5 years
Identifiable intangible assets, Fair Value			$ 1,800

Acquisitions and Transactions50

Acquisitions and Transactions - Key Assumptions Used in Valuation of Identifiable Intangible Assets (Details) - North Alabama Cancer Care Organization ('NACCO") - Identifiable Intangible Assets, Excluding CONs	Nov. 01, 2016
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Discount rate	9.00%
Perpetual growth rate	1.00%
Tax rate	38.00%
Risk-free rate	4.00%
Peer company beta	0.69

Acquisitions and Transactions51

Acquisitions and Transactions - Level 3 Estimates and Assumptions (Details) - North Alabama Cancer Care Organization ('NACCO") - Non-controlling Interest - Level 3	Nov. 01, 2016
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
Discount rate	16.30%
Perpetual growth rate	3.00%
Tax rate	39.20%
Risk-free rate	1.90%
Minimum
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
EBITDA multiple	4.1
Maximum
Schedule of Business Acquisitions and Restructuring Transactions [Line Items]
EBITDA multiple	5.9

Acquisitions and Transactions52

Acquisitions and Transactions - Schedule of Business Combination, Assets and Liabilities Acquired (Details) - USD ($) $ in Thousands	Aug. 01, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$ 119,130	$ 102,782	$ 63,864
Alliance HNI LLC
Business Acquisition [Line Items]
The Company’s equity investment in AHNVPS transferred to AHNI	$ 721
Certain equipment transferred to AHNI by the Company	477
Total consideration	1,198
Fair value of the Company’s equity interest held in AHNI before the business combination	13,645
Cash	1,848
Accounts receivable, net	2,064
Equipment, net	6,962
Intangible assets	13,700
Other assets	1,919
Long term debt	(4,110)
Other liabilities	(1,095)
Total recognized net assets	21,288
Noncontrolling interest in AHNI	9,463
Goodwill	$ 2,988

Acquisitions and Transactions53

Acquisitions and Transactions - Schedule of Pro Forma Results of Acquisitions (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Combinations [Abstract]
Total revenues	$ 524,247	$ 522,347	$ 503,323
Net income attributable to the Company	$ 3,547	$ 13,703	$ 16,773
Basic earnings per share	$ 0.33	$ 1.28	$ 1.57
Diluted earnings per share	$ 0.32	$ 1.26	$ 1.55

Acquisitions and Transactions54

Acquisitions and Transactions - Restructuring Charges (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 1,635	$ 1,327	$ 2,602
Cost of Revenues Excluding Depreciation and Amortization
Restructuring Cost And Reserve [Line Items]
Restructuring charges	787	900	1,440
Selling, General and Administrative Expenses
Restructuring Cost And Reserve [Line Items]
Restructuring charges	275	175	1,162
Severance and Related Costs
Restructuring Cost And Reserve [Line Items]
Restructuring charges	0	27	0
Amortization Expense
Restructuring Cost And Reserve [Line Items]
Restructuring charges	0	225	0
Other Expense, Net
Restructuring Cost And Reserve [Line Items]
Restructuring charges	$ 573	$ 0	$ 0

Share-Based Payment - Additiona

Share-Based Payment - Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Nov. 30, 1999
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares authorized for grant of options and awards (shares)					3,005,000
Common stock shares available for grant of options and awards (shares)		948,886
Aggregate intrinsic value of options exercised		$ 1,400,000	$ 25,000	$ 1,600,000
Total fair value of stock options vested		2,300,000	$ 1,100,000	$ 837,000
Cash right paid		$ 463,000
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options term		10 years
Options accelerated due to employment agreements vesting (shares)		71,057	0	0
Stock Options | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		3 years
Stock Options | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of awards granted, in shares		175,441
Total fair value of RSUs vested		$ 683,000	$ 692,000	$ 337,000
RSUs | Executive Management
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of awards granted, in shares	25,000
Minimum market price that must be achieved (per share)		$ 40
Duration of minimum market price		10 days
RSUs | Tahoe Investment Group Co., Ltd | Executive Management
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Per share consideration received by the holders of the Company's common stock upon the consummation of the transaction		$ 18.50
Cash right paid		$ 463,000

Share-Based Payment - Weighted

Share-Based Payment - Weighted Average Assumptions for Fair Value of Stock Options (Details) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Weighted average assumptions for stock option awards
Risk free interest rate	1.53%	1.65%	1.83%
Expected dividend yield	0.00%	0.00%	0.00%
Expected stock price volatility	66.50%	65.20%	66.30%
Average expected life (in years)	6 years	6 years	6 years
Weighted average grant date fair value	$ 4.32	$ 14.25	$ 17.56

Share-Based Payment - Stock Opt

Share-Based Payment - Stock Option Activity (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)$ / sharesshares
Number of Shares
Beginning balance | shares	646,290
Granted | shares	200,388
Exercised | shares	(121,667)
Canceled/forfeited | shares	(74,042)
Ending balance | shares	650,969
Vested and expected to vest in the future | shares	612,122
Vested and exercisable | shares	463,165
Weighted Average Exercise Price
Beginning balance | $ / shares	$ 19.91
Granted | $ / shares	7.16
Exercised | $ / shares	5.05
Canceled/forfeited | $ / shares	22.08
Ending balance | $ / shares	18.51
Vested and expected to vest in the future | $ / shares	19.23
Vested and exercisable | $ / shares	$ 23.11
Weighted Average Remaining Contractual Term
Outstanding at December 31, 2016	6 years 4 months 24 days
Vested and expected to vest in the future	6 years 2 months 12 days
Vested and exercisable	5 years 2 months 12 days
Aggregate Intrinsic Value
Outstanding at December 31, 2016 | $	$ 917	[1]
Vested and expected to vest in the future | $	823	[1]
Vested and exercisable | $	$ 462	[1]
[1]	Represents the difference between the exercise price and the value of the Company’s stock at fiscal year-end

Share-Based Payment - Exercise

Share-Based Payment - Exercise Price Range (Details)	12 Months Ended
	Dec. 31, 2016$ / sharesshares
$5.70 - $6.29
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (dollars per share)	$ 5.70
Exercise price range, upper range limit (dollars per share)	$ 6.29
Number of options outstanding (shares) | shares	127,002
Weighted average exercise price (dollars per share) - Options Outstanding	$ 5.96
Remaining contractual term (years) - Options Outstanding	5 years
Number of options exercisable (shares) | shares	127,002
Weighted average exercise price (dollars per share) - Options Exercisable	$ 5.96
Remaining contractual term (years) - Options Exercisable	5 years
$6.30 - $6.93
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (dollars per share)	$ 6.30
Exercise price range, upper range limit (dollars per share)	$ 6.93
Number of options outstanding (shares) | shares	145,804
Weighted average exercise price (dollars per share) - Options Outstanding	$ 6.93
Remaining contractual term (years) - Options Outstanding	9 years 2 months 12 days
Number of options exercisable (shares) | shares	0
Weighted average exercise price (dollars per share) - Options Exercisable	$ 0
Remaining contractual term (years) - Options Exercisable	0 years
$6.94 - $22.43
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (dollars per share)	$ 6.94
Exercise price range, upper range limit (dollars per share)	$ 22.43
Number of options outstanding (shares) | shares	67,287
Weighted average exercise price (dollars per share) - Options Outstanding	$ 9.79
Remaining contractual term (years) - Options Outstanding	8 years 1 month 6 days
Number of options exercisable (shares) | shares	25,287
Weighted average exercise price (dollars per share) - Options Exercisable	$ 12.70
Remaining contractual term (years) - Options Exercisable	6 years 4 months 24 days
$22.44 - $28.46
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (dollars per share)	$ 22.44
Exercise price range, upper range limit (dollars per share)	$ 28.46
Number of options outstanding (shares) | shares	67,609
Weighted average exercise price (dollars per share) - Options Outstanding	$ 24.01
Remaining contractual term (years) - Options Outstanding	8 years 1 month 6 days
Number of options exercisable (shares) | shares	67,609
Weighted average exercise price (dollars per share) - Options Exercisable	$ 24.01
Remaining contractual term (years) - Options Exercisable	8 years 1 month 6 days
$28.47 - $28.92
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (dollars per share)	$ 28.47
Exercise price range, upper range limit (dollars per share)	$ 28.92
Number of options outstanding (shares) | shares	58,815
Weighted average exercise price (dollars per share) - Options Outstanding	$ 28.61
Remaining contractual term (years) - Options Outstanding	4 years 7 months 6 days
Number of options exercisable (shares) | shares	58,815
Weighted average exercise price (dollars per share) - Options Exercisable	$ 28.61
Remaining contractual term (years) - Options Exercisable	4 years 7 months 6 days
$28.93 - $30.27
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (dollars per share)	$ 28.93
Exercise price range, upper range limit (dollars per share)	$ 30.27
Number of options outstanding (shares) | shares	102,952
Weighted average exercise price (dollars per share) - Options Outstanding	$ 29.14
Remaining contractual term (years) - Options Outstanding	6 years 8 months 12 days
Number of options exercisable (shares) | shares	102,952
Weighted average exercise price (dollars per share) - Options Exercisable	$ 29.14
Remaining contractual term (years) - Options Exercisable	6 years 8 months 12 days
$30.28 - $46.30
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (dollars per share)	$ 30.28
Exercise price range, upper range limit (dollars per share)	$ 46.30
Number of options outstanding (shares) | shares	81,500
Weighted average exercise price (dollars per share) - Options Outstanding	$ 40.72
Remaining contractual term (years) - Options Outstanding	1 year 3 months 18 days
Number of options exercisable (shares) | shares	81,500
Weighted average exercise price (dollars per share) - Options Exercisable	$ 40.72
Remaining contractual term (years) - Options Exercisable	1 year 3 months 18 days
$5.70 - $46.30
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, lower range limit (dollars per share)	$ 5.70
Exercise price range, upper range limit (dollars per share)	$ 46.30
Number of options outstanding (shares) | shares	650,969
Weighted average exercise price (dollars per share) - Options Outstanding	$ 18.52
Remaining contractual term (years) - Options Outstanding	6 years 4 months 24 days
Number of options exercisable (shares) | shares	463,165
Weighted average exercise price (dollars per share) - Options Exercisable	$ 23.11
Remaining contractual term (years) - Options Exercisable	5 years 2 months 12 days

Share-Based Payment - Unvested

Share-Based Payment - Unvested Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Shares
Beginning balance		158,671
Granted		200,388
Vested		(156,171)
Forfeited		(15,084)
Ending balance		187,804	158,671
Weighted Average Grant Date Fair Value
Beginning balance		$ 15.01
Granted		4.32	$ 14.25	$ 17.56
Vested		15.05
Forfeited		5.60
Ending balance		$ 4.33	$ 15.01
Stock Options
Aggregate Unrecognized Compensation
Aggregate unrecognized compensation	[1]	$ 476
Weighted average period over which expected to be recognized (in years)		2 years 2 months 12 days
[1]	The valuation model applied in this calculation utilizes highly subjective assumptions that could potentially change over time, including the expected forfeiture rate and performance targets. Therefore, the amount of unrecognized share-based payment noted above does not necessarily represent the value that will ultimately be realized by the Company in the consolidated statements of income and comprehensive income.

Share-Based Payment - RSU Activ

Share-Based Payment - RSU Activity (Details) - Restricted stock units $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)$ / sharesshares
Rollforward of RSU activity - Shares
Beginning balance, unvested (shares) | shares	74,413
Granted (shares) | shares	175,441
Vested (shares) | shares	(74,413)
Forfeited (shares) | shares	(7,588)
Ending balance, unvested (shares) | shares	167,853
Rollforward of RSU Activity - Weighted Average Grant Date Fair Value
Beginning balance, unvested, weighted-average grant-date fair value (dollars per share) | $ / shares	$ 9.18
Granted, weighted-average grant-date fair value (dollars per share) | $ / shares	8.30
Vested, weighted-average grant-date fair value (dollars per share) | $ / shares	9.18
Forfeited, weighted-average grant-date fair value (dollars per share) | $ / shares	6.93
Ending balance, unvested, weighted-average grant-date fair value (dollars per share) | $ / shares	$ 8.37
Aggregate Unrecognized Compensation
Aggregate unrecognized compensation | $	$ 1,182
Weighted average period over which expected to be recognized (in years)	1 year 3 months 18 days

Share-Based Payments - Summary

Share-Based Payments - Summary of Share-Based Compensation Expense (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	[1]	Dec. 31, 2015	Dec. 31, 2014
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Income tax benefit		$ (936)		$ (595)	$ (540)
Total share-based compensation expense after income taxes		2,240		1,106	975
Selling, General and Administrative Expenses
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	[2]	$ 3,176		$ 1,701	$ 1,515
[1]	Includes Cash Right of $463.
[2]	Included in “Selling, general and administrative expenses” in the Company’s consolidated statement of income and comprehensive income.

Share-Based Payments - Summar62

Share-Based Payments - Summary of Share-Based Compensation Expense (Parenthetical) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
Share Based Compensation [Abstract]
Cash right paid	$ 463

Fair Value of Financial Instr63

Fair Value of Financial Instruments - Summary of Valuation of Financial Instruments Reported at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financial liabilities:
Contingent consideration related to acquisitions	$ 555	$ 5,750
Mandatorily redeemable noncontrolling interest	2,386	2,386
Recurring basis
Financial assets:
Interest rate contracts - asset position	55	0
Total financial assets	55	0
Financial liabilities:
Contingent consideration related to acquisitions	555	5,750
Mandatorily redeemable noncontrolling interest	2,386	2,386
Interest rate contracts - liability position	53	86
Total financial liabilities	2,994	8,222
Recurring basis | Level 1
Financial assets:
Interest rate contracts - asset position	0	0
Total financial assets	0	0
Financial liabilities:
Contingent consideration related to acquisitions	0	0
Mandatorily redeemable noncontrolling interest	0	0
Interest rate contracts - liability position	0	0
Total financial liabilities	0	0
Recurring basis | Level 2
Financial assets:
Interest rate contracts - asset position	55	0
Total financial assets	55	0
Financial liabilities:
Contingent consideration related to acquisitions	0	0
Mandatorily redeemable noncontrolling interest	0	0
Interest rate contracts - liability position	53	86
Total financial liabilities	53	86
Recurring basis | Level 3
Financial assets:
Interest rate contracts - asset position	0	0
Total financial assets	0	0
Financial liabilities:
Contingent consideration related to acquisitions	555	5,750
Mandatorily redeemable noncontrolling interest	2,386	2,386
Interest rate contracts - liability position	0	0
Total financial liabilities	$ 2,941	$ 8,136

Fair Value of Financial Instr64

Fair Value of Financial Instruments - Schedule of Changes in Fair Value of Level 3 Liabilities (Details) - Level 3 - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Contingent Consideration Related to Acquisitions
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance		$ 5,750	$ 0
Additions	[1]	420	5,750
Settlement of contingent consideration related to acquisitions		(825)
Fair value adjustment	[2]	(4,790)
Ending Balance		555	5,750
Mandatorily Redeemable Noncontrolling Interest
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning Balance		2,386	0
Additions	[1]	0	2,386
Settlement of contingent consideration related to acquisitions		0
Fair value adjustment	[2]	0
Ending Balance		$ 2,386	$ 2,386
[1]	See Note 3.
[2]	Adjustments to the estimated fair value of the contingent consideration are related to the actual versus expected performance of acquisitions and are included in “Other income, net” in the Company’s consolidated statement of income and comprehensive income.

Fair Value of Financial Instr65

Fair Value of Financial Instruments - Summary of Financial Instruments Measured and Recorded at Fair Value on a Recurring Basis (Details) - Recurring basis - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financial assets:
Other assets	$ 55	$ 0
Total financial assets	55	0
Financial liabilities:
Other accrued liabilities	2,994	8,139
Other liabilities	0	83
Total financial liabilities	2,994	8,222
Level 1
Financial assets:
Other assets	0	0
Total financial assets	0	0
Financial liabilities:
Other accrued liabilities	0	0
Other liabilities	0	0
Total financial liabilities	0	0
Level 2
Financial assets:
Other assets	55	0
Total financial assets	55	0
Financial liabilities:
Other accrued liabilities	53	3
Other liabilities	0	83
Total financial liabilities	53	86
Level 3
Financial assets:
Other assets	0	0
Total financial assets	0	0
Financial liabilities:
Other accrued liabilities	2,941	8,136
Other liabilities	0	0
Total financial liabilities	$ 2,941	$ 8,136

Fair Value of Financial Instr66

Fair Value of Financial Instruments - Summary of Fair Values and Book Values of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term Debt, Book Value	$ 574,557
Level 2
Debt Instrument [Line Items]
Long-term Debt, Fair Value	568,047	$ 578,782
Long-term Debt, Book Value	573,247	577,685
Level 2 | Variable-Rate Debt
Debt Instrument [Line Items]
Long-term Debt, Fair Value	526,475	538,520
Long-term Debt, Book Value	533,939	537,018
Level 2 | Fixed-Rate Debt
Debt Instrument [Line Items]
Long-term Debt, Fair Value	41,572	40,262
Long-term Debt, Book Value	$ 39,308	$ 40,667

Impairment Charges - Additional

Impairment Charges - Additional Information (Details) - USD ($)	Oct. 01, 2016	Oct. 01, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Impairment Charges [Line Items]
Impairment of indefinite-lived intangible assets	$ 0	$ 0	$ 0	$ 0
Oncology
Impairment Charges [Line Items]
Impairment of indefinite-lived intangible assets					$ 882,000	$ 6,700,000
Impairment of equity investment in Oncology site location							$ 308,000

Impairment Charges - Level 3 Es

Impairment Charges - Level 3 Estimates and Assumptions (Details) - Certificates Of Need Related To Oncology Site In Alabama - Level 3	12 Months Ended
	Dec. 31, 2016
Fair Value Inputs Assets Quantitative Information [Line Items]
Discount rate	16.00%
Perpetual growth rate	3.00%
Tax rate	39.20%
Risk-free rate	2.00%
Minimum
Fair Value Inputs Assets Quantitative Information [Line Items]
EBITDA multiple	4
Maximum
Fair Value Inputs Assets Quantitative Information [Line Items]
EBITDA multiple	6

Goodwill and Intangible Asset69

Goodwill and Intangible Assets - Changes in the Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Line Items]
Beginning balance	$ 102,782	$ 63,864
Goodwill acquired during the period	15,305	38,918
Adjustments to goodwill during the period	1,043
Ending balance	119,130	102,782
Gross goodwill	293,374
Accumulated impairment charges	(174,244)
Radiology
Goodwill [Line Items]
Beginning balance	44,822	42,166
Goodwill acquired during the period	335	2,656
Adjustments to goodwill during the period	0
Ending balance	45,157	44,822
Gross goodwill	199,499
Accumulated impairment charges	(154,342)
Oncology
Goodwill [Line Items]
Beginning balance	27,589	21,698
Goodwill acquired during the period	14,116	5,891
Adjustments to goodwill during the period	615
Ending balance	42,320	27,589
Gross goodwill	62,222
Accumulated impairment charges	(19,902)
Interventional
Goodwill [Line Items]
Beginning balance	30,371	0
Goodwill acquired during the period	854	30,371
Adjustments to goodwill during the period	428
Ending balance	31,653	$ 30,371
Gross goodwill	31,653
Accumulated impairment charges	$ 0

Goodwill and Intangible Asset70

Goodwill and Intangible Assets - Summary of Level 3 Estimates and Assumptions (Details) - Goodwill	Oct. 01, 2016	Oct. 01, 2015
Fair Value Inputs Assets Quantitative Information [Line Items]
Perpetual growth rate		2.50%
Tax rate	40.00%	40.00%
Risk-free rate	4.00%	2.50%
EBITDA multiple	5.5
Minimum
Fair Value Inputs Assets Quantitative Information [Line Items]
Discount rate	10.00%	10.00%
Perpetual growth rate	1.00%
Peer company beta	0.5	0.8
Revenue multiple	1	1
EBITDA multiple		5.5
Maximum
Fair Value Inputs Assets Quantitative Information [Line Items]
Discount rate	13.00%	15.00%
Perpetual growth rate	3.00%
Peer company beta	0.6	1.2
Revenue multiple	1.35	1.5
EBITDA multiple		6

Goodwill and Intangible Asset71

Goodwill and Intangible Assets - Additional Information (Details) - USD ($)	Oct. 01, 2016	Oct. 01, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Goodwill And Intangible Assets [Line Items]
Impairment of goodwill					$ 0	$ 0
Impairment of indefinite-lived intangible assets	$ 0	$ 0	$ 0	$ 0
Radiology
Goodwill And Intangible Assets [Line Items]
Reporting unit, percentage of fair value in excess of carrying amount	103.00%
Oncology
Goodwill And Intangible Assets [Line Items]
Reporting unit, percentage of fair value in excess of carrying amount	6.00%
Impairment of indefinite-lived intangible assets					$ 882,000	$ 6,700,000
Interventional
Goodwill And Intangible Assets [Line Items]
Reporting unit, percentage of fair value in excess of carrying amount	8.00%

Goodwill and Intangible Asset72

Goodwill and Intangible Assets - Components of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Finite-lived intangible assets:
Weighted average useful life (in years)	16 years
Gross carrying amount	$ 272,143	$ 224,838
Accumulated amortization	(123,381)	(112,820)
Amortizing intangible assets, net	148,762	112,018
Indefinite-lived intangible assets	50,215	50,905
Total other intangible assets	$ 198,977	162,923
Customer contracts
Finite-lived intangible assets:
Weighted average useful life (in years)	16 years
Gross carrying amount	$ 230,323	186,316
Accumulated amortization	(101,240)	(92,280)
Amortizing intangible assets, net	$ 129,083	94,036
Other
Finite-lived intangible assets:
Weighted average useful life (in years)	18 years
Gross carrying amount	$ 41,820	38,522
Accumulated amortization	(22,141)	(20,540)
Amortizing intangible assets, net	$ 19,679	$ 17,982

Goodwill and Intangible Asset73

Goodwill and Intangible Assets - Estimated Annual Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Finite-lived intangible assets:
2,017	$ 13,062
2,018	12,689
2,019	12,200
2,020	11,710
2,021	10,802
Thereafter	88,299
Amortizing intangible assets, net	$ 148,762	$ 112,018

Supplemental Balance Sheet In74

Supplemental Balance Sheet Information - Plant, Property and Equipment Net (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property Plant And Equipment [Line Items]
Cost	$ 939,810	$ 883,804
Accumulated Depreciation	(734,996)	(706,616)
Net Carrying Amount	204,814	177,188
Furniture and fixtures
Property Plant And Equipment [Line Items]
Cost	4,905	4,825
Accumulated Depreciation	(4,231)	(3,977)
Net Carrying Amount	674	848
Office equipment
Property Plant And Equipment [Line Items]
Cost	80,384	71,245
Accumulated Depreciation	(57,295)	(49,981)
Net Carrying Amount	23,089	21,264
Transportation and service equipment
Property Plant And Equipment [Line Items]
Cost	16,140	5,884
Accumulated Depreciation	(4,291)	(3,306)
Net Carrying Amount	11,849	2,578
Major equipment
Property Plant And Equipment [Line Items]
Cost	794,153	758,718
Accumulated Depreciation	(639,452)	(623,429)
Net Carrying Amount	154,701	135,289
Tenant improvements
Property Plant And Equipment [Line Items]
Cost	43,888	42,792
Accumulated Depreciation	(29,665)	(25,904)
Net Carrying Amount	14,223	16,888
Buildings and land
Property Plant And Equipment [Line Items]
Cost	340	340
Accumulated Depreciation	(62)	(19)
Net Carrying Amount	$ 278	$ 321

Supplemental Balance Sheet In75

Supplemental Balance Sheet Information - Additional Information (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Major equipment
Property Plant And Equipment [Line Items]
Assets held under capital leases, gross	$ 24,900,000	$ 19,300,000
Assets held under capital leases, accumulated depreciation	9,400,000	$ 7,000,000
Transportation and service equipment
Property Plant And Equipment [Line Items]
Assets held under capital leases, gross	2,800,000
Assets held under capital leases, accumulated depreciation	$ 209,000

Supplemental Balance Sheet In76

Supplemental Balance Sheet Information - Components of Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Components of other accrued liabilities
Systems rental and maintenance costs	$ 1,064	$ 1,808
Site rental fees	899	1,121
Property and sales taxes payable	7,254	8,695
Self-insurance expense	2,612	2,037
Legal fees	1,537	1,971
Deferred gain on sale of equipment	87	312
Equipment purchases	848	4,756
Customer overpayments	2,555	1,580
Contingent consideration related to acquisition	555	5,750
Mandatorily redeemable noncontrolling interest	2,386	2,386
Other expenses	9,526	6,037
Total	$ 29,323	$ 36,453

Long-Term Debt and Senior Sub77

Long-Term Debt and Senior Subordinated Credit Facility - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term debt, gross	$ 574,557
Deferred financing costs, net	(24,502)	$ (6,594)
Long-term debt, including current portion	548,745	571,091
Less current portion	20,652	20,406
Long-term debt	528,093	550,685
Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross	497,674	502,874
Discount on term loan facility	(1,310)	(1,823)
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross	21,500	19,500
Equipment Under Capital Leases
Debt Instrument [Line Items]
Long-term debt, gross	16,040	13,006
Equipment Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 39,343	$ 44,128

Long-Term Debt and Senior Sub78

Long-Term Debt and Senior Subordinated Credit Facility - Additional Information (Details) - USD ($)	Mar. 29, 2016	Jun. 19, 2015	Jun. 03, 2013	Jun. 01, 2013	Jun. 30, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 02, 2013	Oct. 11, 2013	Jul. 03, 2013
Debt Instrument [Line Items]
Long-term debt, gross						$ 574,557,000
Amount of fees paid, which were capitalized and amortized as interest expense						25,741,000	$ 808,000	$ 0
Senior Notes
Debt Instrument [Line Items]
Stated percentage rate			8.00%
Senior Notes, face amount			$ 190,000,000
Principal amount of debt repurchased											$ 80,000,000
Committed Incremental Term Loan
Debt Instrument [Line Items]
Credit facility borrowing capacity		$ 30,000,000
Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross						497,674,000	502,874,000
Quarterly amortization payments			$ 1,100,000
Period over which specified quarterly amortization payments are required			5 years 6 months
New Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt, gross						21,500,000	19,500,000
Prior Credit Facility | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate				4.25%
Prior Credit Facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate				5.25%
Equipment Debt
Debt Instrument [Line Items]
Long-term debt, gross						39,343,000	$ 44,128,000
Equipment Debt | Bank of the West
Debt Instrument [Line Items]
Long-term debt, gross						$ 4,700,000
New Credit Agreement
Debt Instrument [Line Items]
Debt instrument, interest rate terms			Borrowings under the Credit Agreement bear interest through maturity at a variable rate based upon, at the Company’s option, either the LIBOR or the base rate (which is the highest of the administrative agent’s prime rate, one-half of 1.00% in excess of the overnight federal funds rate, and 1.00% in excess of the one-month LIBOR rate), plus, in each case, an applicable margin.
Ownership percentage of subsidiaries			50.00%
Maximum leverage ratio covenant of consolidated total debt to Consolidated Adjusted EBITDA						4.55%
Actual leverage ratio consolidated total debt to Consolidated Adjusted EBITDA						4.03%
Outstanding letters of credit						$ 4,400,000
New Credit Agreement | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate			1.00%
Debt description of variable rate basis			one-month LIBOR
New Credit Agreement | Committed Incremental Term Loan | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate		2.25%
New Credit Agreement | Committed Incremental Term Loan | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		3.25%
New Credit Agreement | Term Loan Facility
Debt Instrument [Line Items]
Credit facility borrowing capacity			$ 340,000,000								$ 340,000,000
Debt term			6 years
New Credit Agreement | Term Loan Facility | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate			2.25%
New Credit Agreement | Term Loan Facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate			3.25%
New Credit Agreement | New Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility borrowing capacity		$ 50,000,000	$ 50,000,000
Debt term			5 years
Credit facility, available borrowings						24,100,000
Revolving loan facility						21,500,000
New Credit Agreement | Letter of Credit
Debt Instrument [Line Items]
Credit facility borrowing capacity			$ 20,000,000
New Credit Agreement | Uncommitted Incremental Loan Facility
Debt Instrument [Line Items]
Credit facility borrowing capacity			$ 100,000,000
Maximum debt leverage ratio allowed for additional incremental loan facilities			3.25%
New Credit Agreement | Delayed Draw
Debt Instrument [Line Items]
Credit facility borrowing capacity			$ 80,000,000
Required draw period			30 days
First Amendment to New Credit Agreement | Committed Incremental Term Loan
Debt Instrument [Line Items]
Credit facility borrowing capacity										$ 70,000,000
Long-term debt, gross									$ 70,000,000
Second Amendment to New Credit Agreement | Committed Incremental Term Loan
Debt Instrument [Line Items]
Principal amount funded (percent)		99.50%
Second Amendment to New Credit Agreement | Term Loan Facility
Debt Instrument [Line Items]
Quarterly amortization payments					$ 1,300,000
Third Amendment to New Credit Agreement
Debt Instrument [Line Items]
Amount of fees paid, which were capitalized and amortized as interest expense	$ 25,000,000
Percentage of premium on prepayment of term loan	1.00%
Debt Assumed from Acquisition of Alliance HNI, LLC and Subsidiaries
Debt Instrument [Line Items]
Notes payable						8,600,000
Debt Assumed from Acquisition of Alliance HNI, LLC and Subsidiaries | Line of Credit
Debt Instrument [Line Items]
Credit facility borrowing capacity						4,700,000
Revolving loan facility						$ 0
Debt Assumed from Acquisition of Alliance HNI, LLC and Subsidiaries | Line of Credit | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate						1.40%
Minimum | Prior Credit Facility | LIBOR
Debt Instrument [Line Items]
LIBOR floor				2.00%
Minimum | Equipment Debt
Debt Instrument [Line Items]
Stated percentage rate						1.94%
Minimum | Equipment Under Capital Leases
Debt Instrument [Line Items]
Stated percentage rate						2.68%
Minimum | New Credit Agreement
Debt Instrument [Line Items]
Maximum leverage ratio covenant of consolidated total debt to Consolidated Adjusted EBITDA			4.30%
Minimum | New Credit Agreement | Committed Incremental Term Loan | LIBOR
Debt Instrument [Line Items]
LIBOR floor		1.00%
Minimum | New Credit Agreement | Term Loan Facility | LIBOR
Debt Instrument [Line Items]
LIBOR floor			1.00%
Minimum | New Credit Agreement | New Revolving Credit Facility
Debt Instrument [Line Items]
Commitment fee, percentage			0.38%
Minimum | New Credit Agreement | New Revolving Credit Facility | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate			2.00%
Minimum | New Credit Agreement | New Revolving Credit Facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate			3.00%
LIBOR floor			1.00%
Minimum | Debt Assumed from Acquisition of Alliance HNI, LLC and Subsidiaries
Debt Instrument [Line Items]
Stated percentage rate						1.94%
Maximum | Equipment Debt
Debt Instrument [Line Items]
Stated percentage rate						9.00%
Maximum | Equipment Under Capital Leases
Debt Instrument [Line Items]
Stated percentage rate						5.98%
Maximum | New Credit Agreement
Debt Instrument [Line Items]
Maximum leverage ratio covenant of consolidated total debt to Consolidated Adjusted EBITDA			4.95%
Maximum | New Credit Agreement | New Revolving Credit Facility
Debt Instrument [Line Items]
Commitment fee, percentage			0.50%
Maximum | New Credit Agreement | New Revolving Credit Facility | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate			2.25%
Maximum | New Credit Agreement | New Revolving Credit Facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate			3.25%
Maximum | Debt Assumed from Acquisition of Alliance HNI, LLC and Subsidiaries
Debt Instrument [Line Items]
Stated percentage rate						2.19%

Long-Term Debt and Senior Sub79

Long-Term Debt and Senior Subordinated Credit Facility - Schedule of Principal Maturities of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Long-term Debt, Fiscal Year Maturity [Abstract]
2,017	$ 21,902
2,018	40,851
2,019	499,840
2,020	10,967
2,021	2,759
Total principal maturities, including imputed interest on equipment under capital leases	576,319
Less: imputed interest on equipment under capital leases	(1,762)
Total principal maturities, excluding imputed interest on equipment under capital leases	574,557
Term Loan Facility
Long-term Debt, Fiscal Year Maturity [Abstract]
2,017	5,200
2,018	5,200
2,019	487,274
2,020	0
2,021	0
Total principal maturities, including imputed interest on equipment under capital leases	497,674
Total principal maturities, excluding imputed interest on equipment under capital leases	497,674	$ 502,874
Revolving Credit Facility
Long-term Debt, Fiscal Year Maturity [Abstract]
2,017	0
2,018	21,500
2,019	0
2,020	0
2,021	0
Total principal maturities, including imputed interest on equipment under capital leases	21,500
Total principal maturities, excluding imputed interest on equipment under capital leases	21,500	$ 19,500
Equipment Under Capital Leases
Long-term Debt, Fiscal Year Maturity [Abstract]
2,017	4,074
2,018	4,065
2,019	4,019
2,020	4,801
2,021	843
Total principal maturities, including imputed interest on equipment under capital leases	17,802
Less: imputed interest on equipment under capital leases	(1,762)
Total principal maturities, excluding imputed interest on equipment under capital leases	16,040
Equipment Loans
Long-term Debt, Fiscal Year Maturity [Abstract]
2,017	12,628
2,018	10,086
2,019	8,547
2,020	6,166
2,021	1,916
Total principal maturities, including imputed interest on equipment under capital leases	$ 39,343

Income Per Common Share (Detail

Income Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Numerator:
Net income attributable to Alliance HealthCare Services, Inc.	$ (2,134)	$ 1,358	$ 2,459	$ (1,190)	$ (252)	$ 7,204	$ (1,961)	$ 1,751	$ 493	$ 6,742	$ 10,618
Denominator:
Weighted average shares-basic (shares)									10,866	10,741	10,669
Effect of dilutive securities:
Stock options and RSUs									93	108	167
Weighted average shares-diluted (shares)									10,959	10,849	10,836
Income per common share attributable to Alliance HealthCare Services, Inc.:
Basic	$ (0.20)	$ 0.12	$ 0.23	$ (0.11)	$ (0.02)	$ 0.67	$ (0.18)	$ 0.16	$ 0.05	$ 0.63	$ 1
Diluted	$ (0.20)	$ 0.12	$ 0.23	$ (0.11)	$ (0.02)	$ 0.67	$ (0.18)	$ 0.16	$ 0.04	$ 0.62	$ 0.98
Stock options excluded from the computation of diluted per share amounts:
Weighted average shares for which the exercise price exceeds average market price of common stock									397	384	337
Average exercise price per share that exceeds average market price of common stock (dollars per share)									$ 27.56	$ 30.16	$ 34.75

Derivatives - Additional Inform

Derivatives - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Variable-Rate Debt
Derivative [Line Items]
Amount of hedged debt	$ 15,500,000	$ 265,900,000
Hedged debt as a percent of total debt (percent)	2.70%	46.00%
Expected reclassification from accumulated other comprehensive loss to interest expense, net over next twelve months	$ 42,000
Interest Rate Cap
Derivative [Line Items]
Notional amount	$ 250,000,000
Effective date	Dec. 31, 2013
Maturity date	Dec. 31, 2016

Derivatives - Summary of Intere

Derivatives - Summary of Interest Rate Cash Flow Hedges (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Liability, Notional Amount		$ 15,522
Fair Value Asset (Liability)	[1]	$ 2	$ (86)
Derivatives designated as hedging instruments | Interest Rate Swap Effective December2012
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative, Maturity Date		Dec. 14, 2017
Derivative Liability, Notional Amount		$ 1,119
Derivative, Fixed Payment Rate		3.75%
Fair Value Asset (Liability)	[1]	$ (3)	(11)
Derivatives designated as hedging instruments | Interest Rate Swap Effective March2013
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative, Maturity Date		Apr. 1, 2018
Derivative Liability, Notional Amount		$ 1,172
Derivative, Fixed Payment Rate		2.87%
Fair Value Asset (Liability)	[1]	$ 0	(2)
Derivatives designated as hedging instruments | Interest Rate Swap Effective December2014
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative, Maturity Date		Nov. 30, 2019
Derivative Liability, Notional Amount		$ 1,003
Derivative, Fixed Payment Rate		1.34%
Fair Value Asset (Liability)	[1]	$ (2)	(7)
Derivatives designated as hedging instruments | Interest Rate Swap Effective December2015
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative, Maturity Date		Dec. 1, 2021
Derivative Liability, Notional Amount		$ 4,663
Derivative, Fixed Payment Rate		3.69%
Fair Value Asset (Liability)	[1]	$ (24)	(54)
Derivatives designated as hedging instruments | Interest Rate Swap Two Effective December2015
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative, Maturity Date		Dec. 15, 2020
Derivative Liability, Notional Amount		$ 1,169
Derivative, Fixed Payment Rate		1.37%
Fair Value Asset (Liability)	[1]	$ 0	(5)
Derivatives designated as hedging instruments | Interest Rate Swap Effective September2016
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative, Maturity Date		Sep. 30, 2021
Derivative Liability, Notional Amount		$ 4,438
Derivative, Fixed Payment Rate		1.17%
Fair Value Asset (Liability)	[1]	$ 33	0
Derivatives not designated hedging instruments | Interest Rate Swap
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Liability, Notional Amount	[2]	1,958
Fair Value Asset (Liability)	[1],[2]	$ (2)	$ (7)
Derivatives not designated hedging instruments | Interest Rate Swap | Minimum
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative, Maturity Date	[2]	Apr. 7, 2017
Derivative, Fixed Payment Rate	[2]	0.75%
Derivatives not designated hedging instruments | Interest Rate Swap | Maximum
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative, Maturity Date	[2]	Apr. 23, 2020
Derivative, Fixed Payment Rate	[2]	1.68%
[1]	The fair values of the interest rate swap assets and liabilities are included in “Other assets” and “Other accrued liabilities,” respectively, in the consolidated balance sheets.
[2]	The Company acquired eight non-designated interest rate swaps (the “AHNI Swaps”) as a result of the step acquisition of AHNI. The changes in fair market value of the AHNI Swaps are recorded in “Interest expense, net” as incurred.

Derivatives - Summary of Inte83

Derivatives - Summary of Interest Rate Cash Flow Hedges (Parenthetical) (Details)	Dec. 31, 2016interest_swaps
Derivatives designated as hedging instruments | LIBOR | Interest Rate Swap Effective December2012
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Interest rate agreement, basis spread on variable rate (percent)	2.50%
Derivatives designated as hedging instruments | LIBOR | Interest Rate Swap Effective March2013
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Interest rate agreement, basis spread on variable rate (percent)	2.00%
Derivatives designated as hedging instruments | LIBOR | Interest Rate Swap One Effective December2015
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Interest rate agreement, basis spread on variable rate (percent)	2.00%
Derivatives not designated hedging instruments | AHNI swaps
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Number of interest swaps	8

Derivatives - Impact on Stateme

Derivatives - Impact on Statement of Income and Comprehensive Income (Details) - Derivatives designated as hedging instruments - Derivatives in Cash Flow Hedging Relationships - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	$ 104	$ (246)
Amount of Loss Reclassified from Accumulated OCI into Income (Effective Portion)	417	25
Amount of Gain Recognized in Income on Derivatives Income (Ineffective Portion)	0	1
Interest rate contracts
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	104	(246)
Interest rate contracts | Interest expense, net
Derivative Instruments Gain Loss [Line Items]
Amount of Loss Reclassified from Accumulated OCI into Income (Effective Portion)	417	25
Amount of Gain Recognized in Income on Derivatives Income (Ineffective Portion)	$ 0	$ 1

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($)	Sep. 09, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies [Line Items]
Maintenance contracts with equipment vendors, expiration year		2,021
Equipment maintenance contract payments		$ 40,900,000	$ 40,400,000	$ 38,900,000
Rental expense		23,000,000	$ 22,800,000	$ 16,800,000
Liability related to guarantees and indemnities		$ 0
Dr. Barry Michael Driver
Commitments and Contingencies [Line Items]
Settlement amount	$ 1,500,000
Agreement settlement date		September 9, 2015
Minimum
Commitments and Contingencies [Line Items]
Period since inception of equipment maintenance contract (years)		1 year
Maximum
Commitments and Contingencies [Line Items]
Period since inception of equipment maintenance contract (years)		5 years
Equipment Purchase Commitments
Commitments and Contingencies [Line Items]
Equipment purchase commitment		$ 17,900,000

Commitments and Contingencies86

Commitments and Contingencies - Future Minimum Operating Lease Payments (Details) $ in Thousands	Dec. 31, 2016USD ($)
Future Minimum Operating Lease Payments
2,017	$ 15,715
2,018	13,872
2,019	7,761
2,020	6,559
2,021	5,590
Thereafter	37,810
Total	$ 87,307

401(k) Savings Plan - Additiona

401(k) Savings Plan - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Compensation And Retirement Disclosure [Abstract]
401(k) plan, minimum eligibility age (years)	21 years
401(k) plan, minimum service period (days)	30 days
401(k) plan, maximum service period (months)	9 months
401(k) plan, minimum employee contribution (percent)	1.00%
401(k) plan, maximum employee contribution (percent)	50.00%
401(k) plan, company employer matching contributions	$ 543,000	$ 778,000	$ 492,000

Income Taxes - Components of In

Income Taxes - Components of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal	$ 85	$ (91)	$ 239
State	264	288	334
Total current	349	197	573
Deferred:
Federal	2,030	5,864	5,858
State	473	475	896
Total deferred	2,503	6,339	6,754
Total income tax expense	$ 2,852	$ 6,536	$ 7,327

Income Taxes - Significant Comp

Income Taxes - Significant Components of Net Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Components of Deferred Tax Assets and Liabilities [Abstract]
Basis differences in equipment	$ (31,376)	$ (24,162)
Basis differences associated with acquired investments	(24,467)	(21,612)
Basis differences in intangible assets	(1,448)	(287)
Net operating losses	19,812	6,841
Accounts receivable	1,303	1,673
State income taxes	685	992
Accruals not currently deductible for income tax purposes	8,372	7,913
Deferred financing costs	(4,391)	0
Other	5,692	5,622
Total deferred taxes	(25,818)	(23,020)
Valuation allowance	0	0
Net deferred taxes	$ (25,818)	$ (23,020)

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Expected Total Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Reconciliation
U.S. federal tax benefit at statutory rates	$ 6,664	$ 10,591	$ 9,861
State income taxes, net of federal benefit	479	496	800
Earnings from unconsolidated investees	451	1,187	1,629
Noncontrolling interest	(5,945)	(7,130)	(5,209)
Shareholder transaction costs	715	737	0
Section 162(m) excess compensation	805	0	0
Changes in fair value of contingent consideration related to acquisition	(508)	0	0
Other	191	655	246
Total income tax expense	$ 2,852	$ 6,536	$ 7,327

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
Alternative minimum tax carryforward	$ 4,600,000
Unrecognized tax benefits related to various federal and state income tax matters	272,000	$ 229,000	$ 269,000	$ 287,000
Tax-effected amount that would reduce the Company's effective income tax rate if recognized	219,000
Accrued interest and penalties related to unrecognized tax benefits	12,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 50,000,000
Domestic Tax Authority | Internal Revenue Service | Earliest Tax Year
Operating Loss Carryforwards [Line Items]
Tax year open to audit	2,013
Domestic Tax Authority | Internal Revenue Service | Latest Tax Year
Operating Loss Carryforwards [Line Items]
Tax year open to audit	2,016
Domestic Tax Authority | Minimum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year start	Jan. 1, 2017
Domestic Tax Authority | Maximum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year start	Dec. 31, 2036
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 36,000,000
State and Local Jurisdiction | Earliest Tax Year
Operating Loss Carryforwards [Line Items]
Tax year open to audit	2,012
State and Local Jurisdiction | Latest Tax Year
Operating Loss Carryforwards [Line Items]
Tax year open to audit	2,016
State and Local Jurisdiction | Minimum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year start	Jan. 1, 2017
State and Local Jurisdiction | Maximum
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year start	Dec. 31, 2036

Income Taxes - Reconciliation92

Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of Unrecognized Tax Benefits
Beginning balance	$ 229,000	$ 269,000	$ 287,000
Increases for positions taken in current year	97,000	51,000	64,000
Increases for positions taken in a prior year	5,000	0	31,000
Decreases for positions taken in a prior year	(9,000)	(11,000)	0
Decreases for lapses in the applicable statute of limitations	(50,000)	(80,000)	(113,000)
Decreases for settlements with taxing authorities	0	0	0
Ending balance	$ 272,000	$ 229,000	$ 269,000

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details)	Dec. 31, 2016unconsolidated_investee	Sep. 16, 2015shares	Aug. 01, 2015unconsolidated_investee
Related Party Transaction [Line Items]
Number of unconsolidated entities with direct ownership (investee)	2
Alliance HNI LLC
Related Party Transaction [Line Items]
Number of unconsolidated entities with direct ownership (investee)			1
Ownership interest, additional percentage acquired	15.50%
Percentage of ownership in unconsolidated investees after step acquisition (percent)	65.50%
Tahoe Investment Group Co Ltd
Related Party Transaction [Line Items]
Number of shares acquired | shares		5,537,945
Ownership interest, percentage acquired	52.00%

Related Party Transactions - Su

Related Party Transactions - Summary of Revenue and Reimbursed Expenses with Unconsolidated Equity Investees (Details) - Equity Method Investee - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Revenue from management agreements	$ 1,473	$ 6,099	$ 9,134
Revenue and reimbursed expenses	$ 1,013	$ 4,879	$ 7,320

Investments in Unconsolidated95

Investments in Unconsolidated Investees - Additional Information (Details) - unconsolidated_investee	12 Months Ended
	Dec. 31, 2016	Aug. 01, 2015
Schedule Of Equity Method Investments [Line Items]
Number of unconsolidated entities with direct ownership (investee)	2
Alliance HNI LLC
Schedule Of Equity Method Investments [Line Items]
Ownership interest, additional percentage acquired		15.50%
Percentage of ownership in unconsolidated investee after step acquisition (percent)		65.50%
Unconsolidated Subsidiary One
Schedule Of Equity Method Investments [Line Items]
Percentage of ownership of investee (percent)	15.00%
Unconsolidated Subsidiary Two
Schedule Of Equity Method Investments [Line Items]
Percentage of ownership of investee (percent)	50.00%
Maximum
Schedule Of Equity Method Investments [Line Items]
Management services agreements' expiration period	2,025

Investments in Unconsolidated96

Investments in Unconsolidated Investees - Balance Sheet Data (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Balance sheet data:
Current assets	$ 2,860	$ 2,644
Noncurrent assets	111	273
Current liabilities	760	676
Noncurrent liabilities	$ 32	$ 35

Investments in Unconsolidated97

Investments in Unconsolidated Investees - Combined Operating Results (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Combined operating results:
Revenues	$ 10,389	$ 20,796	$ 27,735
Expenses	3,055	9,038	13,597
Net income	7,333	11,758	14,138
Earnings from unconsolidated investees	$ 1,290	$ 3,391	$ 4,654

Segment Information - Revenue b

Segment Information - Revenue by Segment (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Summary of revenue by segment
Revenue	$ 129,386	$ 127,121	$ 125,317	$ 123,725	$ 124,337	$ 120,784	$ 118,504	$ 109,429	$ 505,549	$ 473,054	$ 436,387
Operating Segments | Radiology
Summary of revenue by segment
Revenue									350,799	339,627	343,463
Operating Segments | Oncology
Summary of revenue by segment
Revenue									107,220	99,957	92,924
Operating Segments | Interventional
Summary of revenue by segment
Revenue									45,562	33,193	0
Operating Segments | MRI | Radiology
Summary of revenue by segment
Revenue									197,316	183,893	180,815
Operating Segments | PET/CT | Radiology
Summary of revenue by segment
Revenue									126,927	128,356	133,224
Operating Segments | Other Radiology | Radiology
Summary of revenue by segment
Revenue									26,556	27,378	29,424
Corporate / Other
Summary of revenue by segment
Revenue									$ 1,968	$ 277	$ 0

Segment Information - Additiona

Segment Information - Additional Information (Details)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Reconciliation of operating profit (Loss) from segments to consolidated	Adjusted EBITDA represents net income before: income tax expense; interest expense, net; depreciation expense; amortization expense; share-based payment; severance and related costs; noncontrolling interest in subsidiaries; restructuring charges; transaction costs; shareholder transaction costs; impairment charges; legal matters expense, net; changes in fair value of contingent consideration related to acquisitions; non-cash gain on step acquisition; and other non-cash charges, net, which include non-cash (gains) losses on sales of equipment. Adjusted EBITDA is the most frequently used measure of each segment’s performance and is commonly used in setting performance goals.

Segment Information - Summary o

Segment Information - Summary of Adjusted EBITDA (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Summary of Adjusted EBITDA:
Adjusted EBITDA		$ 131,468	$ 131,260	$ 135,755
Segment Continuing Operations
Summary of Adjusted EBITDA:
Adjusted EBITDA	[1]	131,468	131,260	135,755
Segment Continuing Operations | Operating Segments | Radiology
Summary of Adjusted EBITDA:
Adjusted EBITDA	[1]	96,828	94,475	104,681
Segment Continuing Operations | Operating Segments | Oncology
Summary of Adjusted EBITDA:
Adjusted EBITDA	[1]	46,609	43,112	41,846
Segment Continuing Operations | Operating Segments | Interventional
Summary of Adjusted EBITDA:
Adjusted EBITDA	[1]	3,935	5,175	0
Segment Continuing Operations | Corporate / Other
Summary of Adjusted EBITDA:
Adjusted EBITDA	[1]	$ (15,904)	$ (11,502)	$ (10,772)
[1]	Adjusted EBITDA by segment includes inter-segment operating expense allocations from Corporate / Other to Radiology and Oncology of $18.9 million and $6.0 million, respectively, in 2016, $18.9 million and $6.4 million, respectively, in 2015, and $20.9 million and $4.9 million, respectively, in 2014

Segment Information - Summar101

Segment Information - Summary of Adjusted EBITDA (Parenthetical) (Details) - Corporate / Other - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Radiology
Segment Reporting Information [Line Items]
Operating expenses allocations	$ 18.9	$ 18.9	$ 20.9
Oncology
Segment Reporting Information [Line Items]
Operating expenses allocations	$ 6	$ 6.4	$ 4.9

Segment Information - Reconcili

Segment Information - Reconciliation of Income Before Income Taxes, Earnings from Unconsolidated Investees, and Noncontrolling Interest to Total Adjusted EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of net (loss) income to total segment income
Income before income taxes, earnings from unconsolidated investees, and noncontrolling interest	$ 1,412	$ 7,407	$ 8,016	$ 2,205	$ 5,898	$ 17,571	$ 284	$ 6,507	$ 19,040	$ 30,260	$ 28,174
Earnings from unconsolidated investees									1,290	3,391	4,654
Interest expense, net									34,506	26,241	24,693
Depreciation expense									54,972	48,595	54,971
Severance and related costs									3,910	1,347	2,517
Restructuring charges									1,635	1,327	2,602
Transaction costs									1,886	3,296	2,344
Shareholder transaction costs									4,219	1,853	0
Impairment charges									632	6,817	308
Changes in fair value of contingent consideration related to acquisitions									(4,790)	0	0
Total Adjusted EBITDA									131,468	131,260	135,755
Segment Reconciling Items
Reconciliation of net (loss) income to total segment income
Earnings from unconsolidated investees									1,290	3,391	4,654
Interest expense, net									34,506	26,241	24,693
Depreciation expense									54,972	48,595	54,971
Amortization expense									10,561	9,325	7,880
Share-based payment (included in “Selling, general and administrative expenses”)									3,176	1,701	1,515
Severance and related costs									3,910	1,347	2,517
Restructuring charges									1,635	1,327	2,602
Transaction costs									1,886	3,296	2,344
Shareholder transaction costs									4,219	1,853	0
Impairment charges									632	6,817	308
Legal matters expense, net									106	6,915	5,587
Changes in fair value of contingent consideration related to acquisitions									(4,790)	0	0
Non-cash gain on step acquisition (included in “Other income, net”)									0	(10,672)	0
Other non-cash charges (included in “Other income, net”)									$ 325	$ 864	$ 510

Segment Information - Summar103

Segment Information - Summary of Identifiable Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Summary of Company's identifiable assets by segment
Identifiable assets	$ 659,864	$ 603,660	$ 457,795
Operating Segments | Radiology
Summary of Company's identifiable assets by segment
Identifiable assets	301,137	280,497	211,004
Operating Segments | Oncology
Summary of Company's identifiable assets by segment
Identifiable assets	256,456	213,698	182,880
Operating Segments | Interventional
Summary of Company's identifiable assets by segment
Identifiable assets	82,221	83,480
Corporate / Other
Summary of Company's identifiable assets by segment
Identifiable assets	$ 20,050	$ 25,985	$ 63,911

Segment Information - Summar104

Segment Information - Summary of Capital Expenditures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Summary of Company's capital expenditures by segment
Capital expenditures	$ 56,401	$ 55,511	$ 32,386
Operating Segments | Radiology
Summary of Company's capital expenditures by segment
Capital expenditures	50,511	27,478	18,311
Operating Segments | Oncology
Summary of Company's capital expenditures by segment
Capital expenditures	3,043	21,694	3,994
Operating Segments | Interventional
Summary of Company's capital expenditures by segment
Capital expenditures	155	1,287	0
Corporate / Other
Summary of Company's capital expenditures by segment
Capital expenditures	$ 2,692	$ 5,052	$ 10,081

Quarterly Financial Data (Detai

Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 129,386	$ 127,121	$ 125,317	$ 123,725	$ 124,337	$ 120,784	$ 118,504	$ 109,429	$ 505,549	$ 473,054	$ 436,387
Cost of revenues, excluding depreciation and amortization	73,761	71,132	69,939	70,914	72,676	67,057	67,485	61,886	285,746	269,104	237,420
Income before income taxes, earnings from unconsolidated investees and noncontrolling interest	1,412	7,407	8,016	2,205	5,898	17,571	284	6,507	19,040	30,260	28,174
Net income	2,061	5,827	6,188	3,402	5,010	13,065	2,942	6,098	17,478	27,115	25,501
Net (loss) income attributable to Alliance HealthCare Services, Inc.	$ (2,134)	$ 1,358	$ 2,459	$ (1,190)	$ (252)	$ 7,204	$ (1,961)	$ 1,751	$ 493	$ 6,742	$ 10,618
(Loss) income per common share attributable to Alliance HealthCare Services, Inc.:
Basic	$ (0.20)	$ 0.12	$ 0.23	$ (0.11)	$ (0.02)	$ 0.67	$ (0.18)	$ 0.16	$ 0.05	$ 0.63	$ 1
Diluted	$ (0.20)	$ 0.12	$ 0.23	$ (0.11)	$ (0.02)	$ 0.67	$ (0.18)	$ 0.16	$ 0.04	$ 0.62	$ 0.98

Schedule II - Valuation and 106

Schedule II - Valuation and Qualifying Accounts (Details) - Allowance for doubtful accounts - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 5,461	$ 4,055	$ 5,158
Additions	2,255	4,107	2,634
Deductions (Bad Debt Write-offs, net of Recoveries)	(3,708)	(2,701)	(3,737)
Balance at End of Period	$ 4,008	$ 5,461	$ 4,055