Alliance HealthCare Services (AIQ) 10-Q 9 Nov 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Nov. 06, 2015
Document and Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Entity Registrant Name	Alliance HealthCare Services, Inc
Entity Central Index Key	817,135
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		10,750,624

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 44,848	$ 33,033
Accounts receivable, net of allowance for doubtful accounts of $4,055 in 2014 and $5,413 in 2015	69,308	62,503
Deferred income taxes	16,834	16,834
Prepaid expenses	13,598	12,527
Other receivables	2,299	5,686
Total current assets	146,887	130,583
Equipment, at cost	862,640	827,638
Less accumulated depreciation	(687,419)	(678,291)
Equipment, net	175,221	149,347
Goodwill	89,817	63,864
Other intangible assets, net	140,962	115,930
Deferred financing costs, net	7,075	8,119
Other assets	33,272	33,042
Total assets	593,234	500,885
Current liabilities:
Accounts payable	15,520	12,109
Accrued compensation and related expenses	20,041	19,808
Accrued interest payable	3,271	3,154
Income taxes payable	41	0
Other accrued liabilities	26,688	26,542
Current portion of long-term debt	29,915	15,512
Total current liabilities	95,476	77,125
Long-term debt, net of current portion	522,401	491,777
Other liabilities	6,121	6,623
Deferred income taxes	40,892	36,840
Total liabilities	$ 664,890	$ 612,365
Commitments and contingencies
Stockholders’ deficit:
Common stock	$ 107	$ 107
Treasury stock	(3,138)	(3,138)
Additional paid-in capital	28,838	27,653
Accumulated comprehensive loss	(500)	(351)
Accumulated deficit	(187,097)	(194,091)
Total stockholders’ deficit attributable to Alliance HealthCare Services, Inc.	(161,790)	(169,820)
Noncontrolling interest	90,134	58,340
Total stockholders’ deficit	(71,656)	(111,480)
Total liabilities and stockholders’ deficit	$ 593,234	$ 500,885

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 5,413	$ 4,055

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income and Comprehensive Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Revenues	$ 120,784	$ 110,137	$ 348,717	$ 326,740
Costs and expenses:
Cost of revenues, excluding depreciation and amortization	67,057	59,401	196,428	175,968
Selling, general and administrative expenses	24,543	19,811	66,298	57,934
Transaction costs	432	573	1,964	1,512
Severance and related costs	277	455	731	2,315
Impairment charges	71	4	6,817	240
Depreciation expense	12,247	12,743	35,952	42,812
Amortization expense	2,377	1,961	6,907	5,870
Interest expense and other, net	6,660	6,208	19,582	18,570
Other income, net	(10,451)	(602)	(10,324)	(933)
Total costs and expenses	103,213	100,554	324,355	304,288
Income before income taxes, earnings from unconsolidated investees, and noncontrolling interest	17,571	9,583	24,362	22,452
Income tax expense	5,098	2,948	5,304	6,256
Earnings from unconsolidated investees	(592)	(1,219)	(3,047)	(3,459)
Net income	13,065	7,854	22,105	19,655
Less: Net income attributable to noncontrolling interest	(5,861)	(3,843)	(15,111)	(10,928)
Net income attributable to Alliance HealthCare Services, Inc.	7,204	4,011	6,994	8,727
Comprehensive income, net of taxes:
Net income attributable to Alliance HealthCare Services, Inc.	7,204	4,011	6,994	8,727
Unrealized gain (loss) on hedging transactions, net of taxes	(8)	50	(149)	(165)
Comprehensive income, net of taxes	$ 7,196	$ 4,061	$ 6,845	$ 8,562
Income per common share attributable to Alliance HealthCare Services, Inc.:
Basic (dollars per share)	$ 0.67	$ 0.37	$ 0.65	$ 0.82
Diluted (dollars per share)	$ 0.67	$ 0.37	$ 0.65	$ 0.80
Weighted-average number of shares of common stock and common stock equivalents:
Basic (shares)	10,716	10,710	10,715	10,683
Diluted (shares)	10,815	10,851	10,832	10,864

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Operating activities:
Net income	$ 22,105	$ 19,655
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for doubtful accounts	2,373	1,999
Share-based payment	1,242	1,117
Depreciation and amortization	42,859	48,682
Amortization of deferred financing costs	2,602	1,440
Accretion of discount on long-term debt	357	334
Adjustment of derivatives to fair value	100	269
Distributions greater than undistributed earnings from investees	285	581
Deferred income taxes	4,043	1,161
Gain on sale of assets	(685)	(559)
Non-cash gain on step acquisition	9,950	0
Gain on acquisition	(209)	0
Impairment charges	6,817	240
Excess tax benefit from share-based payment arrangements	5	(585)
Changes in operating assets and liabilities, net of the effects of acquisitions:
Accounts receivable	(2,674)	(2,331)
Prepaid expenses	(1,106)	(806)
Other receivables	451	351
Other assets	1,488	(768)
Accounts payable	(363)	451
Accrued compensation and related expenses	(968)	(4,497)
Accrued interest payable	116	1,489
Income taxes payable	55	6
Other accrued liabilities	(4,248)	763
Net cash provided by operating activities	64,695	68,992
Investing activities:
Equipment purchases	(39,382)	(23,194)
Decrease in deposits on equipment	(13,024)	(3,290)
Acquisitions, net of cash received	(22,657)	(1,529)
Proceeds from sale of assets	868	985
Net cash used in investing activities	(74,195)	(27,028)
Financing activities:
Proceeds from equipment debt	23,295	3,843
Principal payments on equipment debt	(6,664)	(8,005)
Proceeds from term loan facility	29,850	0
Principal payments on term loan facility	(8,651)	(3,675)
Principal payments on revolving loan facility	(28,000)	(37,000)
Proceeds from revolving loan facility	26,000	18,000
Payments of debt issuance costs	(801)	0
Noncontrolling interest in subsidiaries	(13,734)	(11,246)
Equity purchase of noncontrolling interest	0	(691)
Excess tax benefit from share-based payment arrangements	(5)	585
Proceeds from shared-based payment arrangements	25	466
Purchase of treasury stock	0	(140)
Net cash (used in) provided by financing activities	21,315	(37,863)
Net change in cash and cash equivalents	11,815	4,101
Cash and cash equivalents, beginning of period	33,033	34,702
Cash and cash equivalents, end of period	44,848	38,803
Supplemental disclosure of cash flow information:
Interest paid	16,973	15,465
Income taxes paid, net of refunds	327	5,974
Supplemental disclosure of non-cash investing and financing activities:
Capital lease obligations related to the purchase of equipment	1,294	0
Unrealized gain (loss) on hedging transactions, net of taxes	(149)	(165)
Equipment purchases in accounts payable	2,417	1,225
Noncontrolling interest assumed in connection with acquisitions (Note 2)	30,417	0
Adjustment to equity of noncontrolling interest	0	1,700
Debt related to purchase of equipment	0	2,112
Extinguishment of note receivable (Note 2)	3,071	$ 0
Transfer of equity investment as consideration in step acquisition (Note 2)	690
Transfer of equipment as consideration in step acquisition (Note 2)	$ 477

Basis of Presentation, Principl

Basis of Presentation, Principles of Consolidation, and Use of Estimates	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation, Principles of Consolidation, and Use of Estimates	Basis of Presentation, Principles of Consolidation, and Use of Estimates Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared by Alliance HealthCare Services, Inc. (the “Company”) in accordance with accounting principles generally accepted in the United States of America and with the instructions to Form 10-Q and Article 10 of Regulation S-X of the Securities and Exchange Commission. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles (“GAAP”) for complete financial statements. In the opinion of management, all adjustments (including normal recurring accruals) considered necessary for a fair presentation have been included. Operating results for the quarter and nine months ended September 30, 2015 are not necessarily indicative of the results that may be expected for the year ending December 31, 2015 . The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes to the consolidated financial statements for the year ended December 31, 2014 . Principles of Consolidation The accompanying unaudited condensed 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 records noncontrolling interest related to its consolidated subsidiaries which are not wholly owned. Investments in unconsolidated investees are accounted for under the equity method. Use of Estimates The preparation of condensed consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates.

Transactions

Transactions	9 Months Ended
	Sep. 30, 2015
Business Combinations, Restructuring and Related Activities [Abstract]
Transactions	Transactions Restructuring Charges During the nine months ended September 30, 2015 , the Company recorded $707 related to restructuring charges, of which the Company recorded $135 in selling, general and administrative expenses, and $572 in cost of revenues, excluding depreciation and amortization. The Company also recorded $731 in severance and related costs during the nine months ended September 30, 2015 . During the nine months ended September 30, 2014 , the Company recorded $2,191 related to restructuring charges, of which the Company recorded $1,112 in selling, general and administrative expenses and $1,079 in cost of revenues, excluding depreciation and amortization. The Company also recorded $2,315 in severance and related costs, primarily as a result of the departure of one of its executive officers during the second quarter of 2014. Acquisition of Alliance-HNI, LLC and Subsidiaries On November 21, 1997, the Company purchased Medical Consultants Imaging, Co. ("MCIC"), which held a 50% interest in a joint venture that was subsequently renamed Alliance-HNI LLC ("AHNI"). Prior to August 1, 2015, the Company's interest in AHNI was deemed a noncontrolling interest and, as such, the Company accounted for the investment using the equity method. On August 1, 2015, the Company obtained an additional 15.5% interest in AHNI, thereby giving it a controlling interest. 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 amounts of the assets acquired and liabilities assumed recognized at the acquisition date, as well as the fair value at the acquisition date of the noncontrolling interest in AHNI: Consideration: The Company's equity investment in AHNVPS transferred to AHNI $ 690 Certain equipment transferred to AHNI by the Company 477 Fair value of total consideration transferred 1,167 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 9,818 Goodwill $ 3,342 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 consolidated those assets before and after the transaction. The intangible assets consist primarily of physician referral network, trademarks, and certificates of need, a portion of which are being amortized over 15.0 years . The results for the quarter and nine months ended September 30, 2015, and the historical results of operations, are not material, and accordingly, pro forma financial information is not presented. 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 5 of the Notes to the Condensed Consolidated Financial Statements. 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 $9,950 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 Condensed Consolidated Statements of Income and Comprehensive Income for the quarter and nine months ended September 30, 2015. 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. Acquisition of The Pain Center of Arizona On February 17, 2015, the Company purchased approximately 59% membership interest in The Pain Center of Arizona ("TPC"), a comprehensive full-time pain management medical practice with 12 locations within the state of Arizona. The acquisition took place in two stages: a purchase of a 60.0% membership interest in TPC by the Company, and a 50.0% membership interest in Medical Practice Innovations, Inc. (“MPI”), followed by a transfer of MPI assets to TPC. The MPI transaction diluted the ownership interests of TPC, with the Company retaining approximately 59% membership interest in TPC. The purchase price consisted of $23,630 in cash, net of $691 cash acquired, and net of extinguishment of $3,071 of related-party notes receivable. The Company financed this acquisition using the revolving line of credit. The following table summarizes recognized amounts of identifiable assets acquired and liabilities assumed at the acquisition date: Cash received $ 691 Accounts receivable, net 4,440 Equipment, net 3,346 Other assets 416 Goodwill 22,611 Identifiable intangible assets 24,600 Debt (2,781 ) Other liabilities (3,532 ) Noncontrolling interest (20,598 ) Total consideration $ 29,193 As a result of this acquisition, the Company recorded goodwill of $22,611 . In addition, the Company recorded intangible assets of $24,600 , of which $13,500 was assigned to physician referral network and $11,100 was assigned to trademarks, which are being amortized over 3 years . The Company recorded the intangible assets at fair value at the acquisition date, which was estimated using the income approach. A portion of the recorded goodwill and intangible assets is being amortized over 15 years for tax purposes. The fair value of noncontrolling interest related to this transaction was $20,598 as of the acquisition date. To estimate the fair value of noncontrolling interest, the Company used the implied fair value based on the Company's ownership percentage. The results for the quarter and nine months ended September 30, 2015 included $8,957 and $20,980 of revenue, respectively, and $804 and $1,095 of net income, respectively, generated by TPC. The historical results of operations of TPC are not material, and accordingly, pro forma financial information is not presented. 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 12 -month period following the transaction date. The fair value of these contingent consideration arrangements of $1,800 was estimated using probability-adjusted performance estimates as of September 30, 2015.

Share-Based Payment

Share-Based Payment	9 Months Ended
	Sep. 30, 2015
Share-based Compensation [Abstract]
Share-Based Payment	Share-Based Payment The Company has adopted ASC 718, “Compensation—Stock Compensation,” and has elected to follow 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. Stock Option Plans and Awards 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 2,205,000 shares have become available for grant. As of September 30, 2015 , a total of 483,341 shares remained available for grant under the 1999 Equity Plan. 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 three or four years , subject to continued service. Certain options contain provisions where vesting may be accelerated due to a change in control of the Company. During the year ended December 31, 2014 and the nine months ended September 30, 2015 there were no options in which vesting was accelerated. Prior to January 1, 2008, stock options granted under the 1999 Equity Plan to employees were all time-vesting options which had 5% vesting in the first year, 20% vesting in the second year and 25% vesting in years three through five. 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 the assumptions noted in the table below. In addition, forfeitures are estimated when recognizing compensation expense and the estimate of forfeitures is 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 are recognized through a cumulative catch-up adjustment in the period of change and impact the amount of compensation expense to be recognized in future periods. The following weighted-average assumptions were used in the estimated grant date fair value calculations for stock option awards: Nine months ended September 30, 2014 2015 Risk free interest rate 1.83 % 1.65 % Expected dividend yield — % — % Expected stock price volatility 66.3 % 65.2 % Average expected life (in years) 6.00 6.00 The Company calculates its stock price volatility and average expected life based on its own historical data. The risk free interest rates are based on the United States Treasury yield curve in effect at the time of grant for periods corresponding with the expected life of the option or award. The following table summarizes the Company’s stock option activity: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term Aggregate Intrinsic Value Outstanding at January 1, 2015 633,898 $ 21.39 Granted 83,514 23.91 Exercised (2,515 ) 10.12 Canceled (34,398 ) 50.58 Outstanding at September 30, 2015 680,499 $ 20.28 5.77 $ 1,055 Vested and expected to vest in the future at September 30, 2015 656,162 $ 20.11 5.70 $ 1,055 Exercisable at September 30, 2015 483,502 $ 18.03 4.93 $ 1,052 The weighted-average grant date fair value of options granted during the nine months ended September 30, 2014 and 2015 was $17.56 per share and $14.25 per share, respectively. Stock options exercised during the nine months ended September 30, 2014 and 2015 totaled 72,794 and 2,515 , respectively. The following table summarizes the Company’s unvested stock option activity: Shares Weighted-Average Grant-Date Fair Value Unvested at January 1, 2015 197,899 $ 12.13 Granted 83,514 14.25 Vested (78,825 ) 6.08 Canceled (5,591 ) 15.16 Unvested at September 30, 2015 196,997 $ 15.40 At September 30, 2015 , the total unrecognized fair value share-based payment related to unvested stock options granted to employees was $1,784 , which is expected to be recognized over a remaining weighted-average period of 1.85 years. 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 Condensed Consolidated Statements of Income and Comprehensive Income. The total fair value of shares vested during the nine months ended September 30, 2014 and 2015 was $469 and $479 , respectively. Stock Awards The 1999 Equity Plan permits the award of restricted stock, restricted stock units, stock bonus awards and performance-based awards. During 2012, awards to certain employees either cliff vested after one year, or vest annually in 33.3% increments over three years. During 2013, awards to certain employees vested immediately upon the date of grant, or cliff vested after one year provided that the employee remained continuously employed through the issuance date. The Company grants restricted stock awards to non-employee directors of the Company who are unaffiliated with Oaktree Capital Management, LLC (“Oaktree”) and MTS Health Investors, LLC (“MTS”) (“unaffiliated directors”). These awards to unaffiliated directors cliff vest after one year based on the unaffiliated directors’ continued service with the Company through that date. For the nine months ended September 30, 2014 and 2015 , the Company recorded share-based payment related to stock awards of $511 and $517 , respectively. Restricted stock units ("RSUs") totaling 25,000 were granted to the Company's Chief Executive Officer in the third quarter of 2014, which vest based upon achieving certain market performance conditions. 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 restricted stock units 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. Since the market condition has not been met, and is currently not probable of being met based on the current market condition, the Company has not recognized any expense related to these RSUs. These RSUs contain provisions that vesting may be accelerated under a change in control of the Company. There were no RSUs granted during the nine months ended September 30, 2015 . The following table summarizes the Company’s restricted stock activity: Shares Weighted-Average Grant-Date Fair Value Unvested at January 1, 2015 32,959 $ 20.99 Granted to employees — — Granted to non-employee directors — — Vested — — Canceled — — Unvested at September 30, 2015 32,959 $ 20.99 At September 30, 2015 , there is no unrecognized fair value share-based payment expense related to restricted stock awards granted to employees. At September 30, 2015 , the total unrecognized fair value share-based payment expense related to the restricted stock awards granted to unaffiliated directors was $173 , which is expected to be recognized during the fourth quarter of 2015. Directors' Compensation Program In 2014 and 2015, under the compensation program for non-employee directors, non-employee directors earn an annual fee of $40 for their services as directors. In addition, each unaffiliated director receives RSUs on December 31 for the number of shares of our common stock having a value equal to $140 , using the average share price of our common stock over the 15 -day period preceding the grant date. These RSUs vest on the first anniversary of their respective date of grant contingent upon the unaffiliated director's continued service to the Company through that date. In addition to the annual fee for all non-employee directors, each affiliated director receives additional annual cash compensation of $140 , paid in one annual installment, for serving on the Board during 2014 and 2015. Non-employee directors who serve as members of our Audit Committee receive an additional $15 , and the non-employee director who serves as Chairman of our Audit Committee receives an additional $30 . Non-employee directors who serve as members of our Nominating Committee and Compensation Committee receive an additional $5 . Non-employee directors are also reimbursed for travel expenses related to their Board service. Beginning October 1, 2013, during the 24 -month period following his resignation as the Company's CEO, the Chairman of the Board, Mr. Buckelew, is granted restricted stock units having a value equal to $138 as compensation for each service period of one year .

Fair Value of Financial Instrum

Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments The Company used the following methods and assumptions in estimating fair value disclosure for financial instruments: Cash and cash equivalents The carrying amounts reported in the balance sheets approximate fair value due to the short-term maturity or variable rates of these instruments. Debt The carrying amount of fixed and variable-rate borrowings at September 30, 2015 was estimated based on current market rates and credit spreads for similar debt instruments. 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. The estimated fair values of the Company’s financial instruments are as follows: December 31, 2014 September 30, 2015 Carrying Value Fair Value Carrying Value Fair Value Cash and cash equivalents $ 33,033 $ 33,033 $ 44,848 $ 44,848 Fixed-rate debt 13,015 13,878 26,874 26,874 Variable-rate debt 494,274 494,354 525,442 525,756 Contingent consideration related to acquisition — — 1,800 1,800 Derivative instruments - asset position 228 228 2 2 Derivative instruments - liability position 46 46 48 48 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 in GAAP 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 will 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. Level 3 Unobservable inputs that are not corroborated by market data. None of the Company’s instruments have transferred from one level to another. The following table summarizes the valuation of the Company’s financial instruments that are reported at fair value on a recurring basis by the above ASC 820 pricing levels as of December 31, 2014: Total Quoted market prices in active markets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Cash and cash equivalents $ 33,033 $ 33,033 $ — $ — Interest rate contracts - asset position 228 228 Interest rate contracts - liability position 46 — 46 — The following table summarizes the valuation of the Company’s financial instruments that are reported at fair value on a recurring basis by the above ASC 820 pricing levels as of September 30, 2015 : Total Quoted market prices in active markets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Cash and cash equivalents $ 44,848 $ 44,848 $ — $ — Contingent consideration related to acquisition 1,800 — — 1,800 Interest rate contracts - asset position 2 — 2 — Interest rate contracts - liability position 48 — 48 — The Company’s derivative instruments are primarily pay-fixed, receive-variable interest rate swaps and caps based on the 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). ASC 820 states that 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 please see Note 9 of the Notes to the Condensed Consolidated Financial Statements. The Company acquired an additional ownership interest in AHNI on August 1, 2015 which resulted in a change in control of the entity. As such, 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. The Company recorded the resulting goodwill and intangible assets at their fair value which was estimated using the income approach and market approach using unobservable Level 3 inputs. The fair value of noncontrolling interest related to the transaction was estimated using the implied fair value based on the Company's ownership percentage. For additional information please see Note 2 of the Notes to the Condensed Consolidated Financial Statements. The Company purchased TPC in February 2015 and recorded the related goodwill and intangible assets at their fair value which was estimated using the income approach and unobservable Level 3 inputs. The fair value of noncontrolling interest related to the transaction was estimated using the implied fair value based on the Company's ownership percentage. For additional information please see Note 2 of the Notes to the Condensed Consolidated Financial Statements. During the quarter ended June 30, 2015, the Company recorded a non-cash charge to write off $6,700 of intangible assets not subject to amortization in its Radiation Oncology division. For additional information please see Note 6 of the Notes to the Condensed Consolidated Financial Statements.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	9 Months Ended
	Sep. 30, 2015
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Revenue Recognition In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU number 2014-09, “Revenue from Contracts with Customers (Topic 606)" to clarify and converge the revenue recognition principles under U.S. GAAP and IFRS 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 adoption of ASU 2014-09 is effective for publicly traded business entities for annual reporting periods beginning after December 15, 2017, including interim reporting periods within that reporting period. Earlier application is not permitted. On April 29, 2015, the FASB proposed a one-year deferral for the effective date of the new standard. The Company is assessing the impact, if any, that the adoption of ASU 2014-09 may have on the Company's results of operations, cash flows, or financial position. Going Concern In August 2014, the FASB issued ASU number 2014-15, "Presentation of Financial Statements—Going Concern (Subtopic 205-40)". Under U.S. 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 Company is assessing the impact, if any, that the adoption of ASU 2014-15 may have on the Company's results of operations, cash flows, or financial position.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Sep. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets Changes in the carrying amount of goodwill are as follows: Balance at January 1, 2014 $ 56,975 Goodwill acquired during the period 6,889 Impairment charges — Adjustments to goodwill during the period — Balance at December 31, 2014 63,864 Goodwill acquired during the period 25,953 Impairment charges — Adjustments to goodwill during the period — Balance at September 30, 2015 $ 89,817 Gross goodwill $ 264,061 Accumulated impairment charges (174,244 ) Balance at September 30, 2015 $ 89,817 Intangible assets consisted of the following: December 31, 2014 September 30, 2015 Gross Carrying Amount Accumulated Amortization Intangible Assets, net Gross Carrying Amount Accumulated Amortization Intangible Assets, net Amortizing intangible assets: Customer contracts $ 162,089 $ (93,617 ) $ 68,472 $ 181,116 $ (100,628 ) $ 80,488 Other 26,241 (21,758 ) 4,483 37,341 (21,572 ) 15,769 Total amortizing intangible assets $ 188,330 $ (115,375 ) $ 72,955 $ 218,457 $ (122,200 ) $ 96,257 Intangible assets not subject to amortization 42,975 44,705 Total other intangible assets $ 115,930 $ 140,962 In 2015, the Company intends to perform an annual impairment test in the fourth quarter for goodwill and indefinite life intangible assets, absent of other events occurring or changes in circumstances that would more likely than not reduce the fair value of a reporting unit below its carrying amount. The Company compares the fair value of its reporting units to its carrying amount to determine if there is potential impairment. The fair value of the reporting unit is determined by an income approach and a market capitalization approach. Significant management judgment is required in the forecasts of future operating results that are used in the income approach. The estimates that the Company has used are consistent with the plans and estimates that it uses to manage its business. The Company bases its fair value estimates on forecasted revenue and operating costs which include a number of factors including, but not limited to, securing new customers, retention of existing customers, growth in radiology and radiation oncology revenues and the impact of continued cost savings initiatives. However, it is possible that plans and estimates may change. During the quarter ended June 30, 2015, the Company implemented a plan to start the process to close a radiation therapy center and, as a result, recorded a non-cash charge to write off $6,700 of intangible assets not subject to amortization associated with that center in its Radiation Oncology division. The revenues from the radiation therapy center were not material for the quarter and nine months ended September 30, 2015. The Company concluded that no other events occurred or circumstances changed relating to any other of its intangible assets during the quarter and nine months ended September 30, 2015 and will perform its annual impairment test for goodwill and other intangibles assets during the fourth quarter of 2015 , as described above. The Company uses the estimated useful life to amortize customer contracts, which range from 2.5 to 20 years. Other intangible assets subject to amortization have a weighted-average useful life of approximately 5.2 years. Amortization expense for intangible assets subject to amortization was $1,961 and $2,377 for the quarters ended September 30, 2014 and 2015 , respectively, and $5,870 and $6,907 for the nine months ended September 30, 2014 and 2015 , respectively. The intangible assets not subject to amortization represent certificates of need and regulatory authority rights which have indefinite useful lives. Estimated annual amortization expense for each of the fiscal years ending December 31, is presented below: 2015 $ 9,419 2016 8,418 2017 7,979 2018 7,471 2019 7,098 Thereafter 62,697

Other Accrued Liabilities

Other Accrued Liabilities	9 Months Ended
	Sep. 30, 2015
Accrued Liabilities, Current [Abstract]
Other Accrued Liabilities	Other Accrued Liabilities Other accrued liabilities consisted of the following: December 31, 2014 September 30, 2015 Accrued systems rental and maintenance costs $ 1,586 $ 2,160 Accrued site rental fees 992 1,052 Accrued property and sales taxes payable 9,276 9,113 Accrued self-insurance expense 2,276 2,609 Deferred gain on sale of equipment 312 312 Other accrued expenses 12,100 11,442 Total $ 26,542 $ 26,688

Long-Term Debt and Senior Subor

Long-Term Debt and Senior Subordinated Credit Facility	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Long-Term Debt and Senior Subordinated Credit Facility	Long-Term Debt and Senior Subordinated Credit Facility Long-term debt consisted of the following: December 31, 2014 September 30, 2015 Term loan facility $ 482,825 $ 504,174 Discount on term loan facility (2,156 ) (1,949 ) Revolving credit facility 2,000 — Equipment debt 24,620 50,091 Long-term debt, including current portion 507,289 552,316 Less current portion 15,512 29,915 Long-term debt $ 491,777 $ 522,401 During the nine months ended September 30, 2015 , the increase in the Company's current portion of long-term debt was primarily due to borrowings for equipment expenditures for its Radiation Oncology division's joint venture with the Medical University of South Carolina ("MUSC"). Debt related to MUSC was funded through a line of credit exclusive of the Company's revolving line of credit, and will be converted to term notes as phases of the project are completed. 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 $340,000 , six -year term loan facility, (ii) a $50,000 , five -year revolving loan facility, including a $20,000 sublimit for letters of credit, (iii) uncommitted incremental loan facilities of $100,000 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) an $80,000 delayed draw term loan facility, which was required to be drawn within thirty days of June 3, 2013 and used for the redemption of $190,000 in aggregate principal amount of the Company's 8% Senior Notes. On July 3, 2013 the delayed draw term loan facility was utilized, of which the proceeds were used to redeem $80,000 in aggregate principal amount of the Company's outstanding 8% Senior Notes that were originally issued in December 2009 as a cash tender offer for any and all of its outstanding 7.25% Notes originally issued in December of 2004. The delayed draw term loan facility converted into, and matched the terms of, the new $340,000 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 London interbank offered rate ("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 facilities, the applicable margin for LIBOR loans is 3.25% per annum, and with respect to the revolving loan facilities, the applicable margin for LIBOR loans ranges, based on the applicable leverage ratio, from 3.00% to 3.25% per annum, in each case, with a LIBOR floor of 1.00% . The applicable margin for base rate loans under the term loan facilities is 2.25% per annum and under the revolving loan facility ranges, based on the applicable leverage ratio, from 2.00% to 2.25% per annum. Prior to the refinancing of the term loan facilities, 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, based on the applicable leverage ratio, from 0.375% to 0.50% per annum on the undrawn portion available under the revolving loan facility and variable per annum fees with respect to outstanding letters of credit. During the first five and three-quarter years after the closing date, and including the full amount of the delayed draw term loan facility, the Company was required to make quarterly amortization payments of the term loans in the amount of $1,050 . 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. 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 that ranges from 4.95 to 1.00 to 4.30 to 1.00. For the quarter ended September 30, 2015 , the Credit Agreement required a maximum leverage ratio of not more than 4.75 to 1.00. The Credit Agreement eliminated the interest coverage ratio covenant which the Company was subject to maintain prior to the refinancing. 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. 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 $70,000 in incremental term loan commitments to repurchase the remaining Notes. On December 2, 2013, the Company borrowed $70,000 of incremental term loans, and with such proceeds plus borrowings under its revolving line of credit and cash on hand, completed the redemption of all of its outstanding Notes on December 4, 2013. 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 $30,000 in incremental term loan commitments. The funds were used to repay all outstanding borrowings under the Company's revolving credit 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 credit facility which remained at $50,000 . The initial portion of the incremental term loan was funded at 99.0% of principal amount under the First Amendment and the remainder was funded at 99.5% of principal under the Second Amendment. The incremental term loan has all of the same terms as the existing term loan facilities and will mature in June 2019. 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. As of September 30, 2015 , there was $504,174 outstanding under the term loan facility, which included the draw term facility and the incremental term facility, and $0 borrowings were outstanding under the revolving credit facility. As of September 30, 2015 , the Company’s ratio of consolidated total debt to consolidated adjusted EBITDA calculated pursuant to the Credit Agreement was 4.11 to 1.00 . The quarterly amortization payments of all term loans under the credit facility for the first five and three-quarter years was initially established at $1,050 . The quarterly amortization payment was increased to $1,225 in December 2013 pursuant to the First Amendment and subsequently increased to $1,300 in June 2015 pursuant to the Second Amendment. Notes Payable and Line of Credit with PNC As a result of the step acquisition on August 1, 2015, and subsequent consolidation of AHNI, the Company had notes payable to PNC totaling $3,880 at September 30, 2015. The notes payable are due in various installments through October 2018 at interest rates between 1.75% and 5.6% per annum. The notes are also collateralized by equipment and contain restrictive covenants. AHNI also has a $4,000 line of credit with PNC, with interest calculated base on LIBOR plus 1.5% . As of September 30, 2015, there was no amount outstanding on the line of credit.

Derivatives

Derivatives	9 Months Ended
	Sep. 30, 2015
Summary of Derivative Instruments [Abstract]
Derivatives	Derivatives The Company accounts for derivative instruments and hedging activities in accordance with the provisions of ASC 815, “Derivatives and Hedging.” Management generally designates derivatives in a hedge relationship with the identified exposure on the date the Company enters into a derivative contract, as disclosed below. The Company has only executed derivative instruments that are economic hedges of exposures that can qualify in hedge relationships under ASC 815. 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 assesses effectiveness of its hedging relationships, both at the hedge inception and on an ongoing basis, then measures and records ineffectiveness. The Company would discontinue hedge accounting prospectively (i) if it is determined that the derivative is no longer effective in offsetting 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, or (iv) 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 their fair value. For additional information please see Note 5 of the Notes to the Condensed Consolidated Financial Statements. For derivatives accounted for as cash flow hedges, any effective unrealized gains or losses on fair value are included in comprehensive income, net of tax, and any ineffective gains or losses are recognized in income immediately. Amounts recorded in comprehensive income are reclassified to earnings when the hedged item impacts earnings. 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. For the nine months ended September 30, 2014 and 2015 , the Company had interest rate swap and cap agreements to hedge approximately $257,769 and $259,887 of its variable rate bank debt, respectively, or 51.0% and 47.1% of total debt, respectively. Over the next twelve months, the Company expects to reclassify $586 from accumulated comprehensive loss to interest expense and other, net. In the first quarter of 2010, the Company entered into three interest rate cap agreements, in accordance with Company policy, to avoid unplanned volatility in the income statement due to changes in the LIBOR interest rate environment. The interest rate cap agreements matured in February 2014 , had a total notional amount of $150,000 , and were de-designated as cash flow hedges associated with the Company’s variable rate bank debt in the fourth quarter of 2013. In the second quarter of 2011, the Company acquired two interest rate swap agreements (the “USR Swaps”) as part of the acquisition of US Radiosurgery, LLC ("USR"). One of the USR Swaps, which matures in October 2015 , had a notional amount of $87 as of September 30, 2015 . Under the terms of this agreement, the Company receives one-month LIBOR and pays a fixed rate of 5.71% . The net effect of the hedge is to record interest expense at a fixed rate of 8.71% , as the underlying debt incurred interest based on one-month LIBOR plus 3.00% . The other USR Swap matured in April 2014 . As a result of the acquisition of USR, the USR Swap was de-designated, hedge accounting was terminated and all further changes in the fair market value of the swap is being recorded in interest expense and other, net. In the fourth quarter of 2012, the Company entered into an interest rate swap agreement in connection with equipment financing. The swap, which matures in December 2017, had a notional amount of $2,457 as of September 30, 2015 . Under the terms of this agreement, the Company receives one-month LIBOR plus 2.50% and pays a fixed rate of 3.75% . The net effect of the hedge is to convert interest expense to a fixed rate of 3.75% , as the underlying debt incurred interest based on one-month LIBOR plus 2.50% . In the first quarter of 2013, the Company entered into an interest rate swap agreement in connection with equipment financing. The swap, which matures in April 2018, had a notional amount of $2,271 as of September 30, 2015 . Under the terms of this agreement, the Company receives one-month LIBOR plus 2.00% and pays a fixed rate of 2.873% . The net effect of the hedge is to convert interest expense to a fixed rate of 2.873% , as the underlying debt incurred interest based on one-month LIBOR plus 2.00% . In the fourth quarter of 2013, the Company entered into five interest rate cap agreements ("2013 Caps"), in accordance with Company policy, to avoid unplanned volatility in the income statement due to changes in the LIBOR interest rate environment. The 2013 Caps, which mature in December 2016, had a notional amount of $250,000 and were designated as cash flow hedges of future cash interest payments associated with a portion of the Company’s variable rate bank debt. Under these arrangements, the Company has purchased a cap on LIBOR at 2.50% . The Company paid $815 to enter into the caps, which is being amortized through interest expense and other, net over the life of the agreements. In the fourth quarter of 2014, the Company entered into an interest rate swap agreement in connection with equipment financing. The swap, which matures in November 2019, had a notional amount of $1,433 as of September 30, 2015 . Under the terms of this agreement, the Company receives one-month LIBOR and pays a fixed rate of 1.34% . The net effect of the hedge is to convert interest expense to a fixed rate of 1.34% , as the underlying debt incurred interest based on one-month LIBOR. In the third quarter of 2015, the Company acquired eight non-designated interest rate swaps (the "AHNI Swaps") as a result of the step acquisition of AHNI. The AHNI swaps mature on various dates ranging from April 2017 through April 2020 and had notional amounts totaling $3,639 as of September 30, 2015 . Under the terms of these arrangements, the Company receives one-month LIBOR and pays fixed rates ranging from 0.85% to 1.17% . The changes in fair market value of the AHNI Swaps are recorded in interest expense and other, net, as incurred. The Effect of Designated Derivative Instruments on the Statement of Operations For the Quarter Ended September 30, 2014 Derivatives in Cash Flow Hedging Relationships Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Location of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Amount of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Interest rate contracts $ 80 Interest expense and other, net $ 8 Interest expense and other, net $ 1 The Effect of Designated Derivative Instruments on the Statement of Operations For the Nine Months Ended September 30, 2014 Derivatives in Cash Flow Hedging Relationships Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Location of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Amount of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Interest rate contracts $ (399 ) Interest expense and other, net $ (117 ) Interest expense and other, net $ (1 ) The Effect of Designated Derivative Instruments on the Statement of Operations For the Quarter Ended September 30, 2015 Derivatives in Cash Flow Hedging Relationships Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Location of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Amount of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Interest rate contracts $ (11 ) Interest expense and other, net $ (7 ) Interest expense and other, net $ — The Effect of Designated Derivative Instruments on the Statement of Operations For the Nine Months Ended September 30, 2015 Derivatives in Cash Flow Hedging Relationships Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Location of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Amount of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Interest rate contracts $ (219 ) Interest expense and other, net $ 9 Interest expense and other, net $ 1 The Effect of Non-Designated Derivative Instruments on the Statements of Operations for the quarter and nine months ended September 30, 2014 and 2015 was immaterial.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes For the quarter and nine months ended September 30, 2014 , the Company recorded income tax expense of $2,948 and $6,256 , or 42.4% and 41.8% , of the Company’s pretax income. For the quarter and nine months ended September 30, 2015 , the Company recorded income tax expense of $5,098 and $5,304 , or 41.4% and 43.1% , of the Company’s pretax income. The Company’s effective tax rate for the quarter and nine months ended September 30, 2015 differed from the federal statutory rate principally as a result of state income taxes and permanent non-deductible items, including share-based payments, unrecorded tax benefits, and other permanent differences. As of September 30, 2015 , the Company has provided a liability for $252 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 $205 . The Company recognizes accrued interest and penalties related to unrecognized tax benefits in income tax expense. As of September 30, 2015 , the Company had approximately $13 in accrued interest and penalties related to unrecognized tax benefits. The Company is subject to United States federal income tax as well as income tax of multiple state tax jurisdictions. The Company is currently open to audit under the statute of limitations by the Internal Revenue Service for the years ended December 31, 2011 through 2014. The Company’s and its subsidiaries’ state income tax returns are open to audit under the applicable statutes of limitations for the years ended December 31, 2010 through 2014. The Company does not anticipate a significant change to the total amount of unrecognized tax benefits within the next 12 months .

Earnings Per Common Share

Earnings Per Common Share	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings Per Common Share Basic net income per share is computed utilizing the two-class method and is calculated based on the weighted-average number of common shares outstanding during the periods presented, excluding nonvested restricted stock units which do not contain nonforfeitable rights to dividend and dividend equivalents. Diluted net income per share is computed using the weighted-average number of common and common equivalent shares outstanding during the periods utilizing the two-class method for stock options, nonvested restricted stock and nonvested restricted stock units. Potentially dilutive securities are not considered in the calculation of net loss per share as their impact would be anti-dilutive. The following table sets forth the computation of basic and diluted earnings per share: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Numerator: Net income attributable to Alliance HealthCare Services, Inc. $ 4,011 $ 7,204 $ 8,727 $ 6,994 Denominator: Weighted-average shares-basic 10,710 10,716 10,683 10,715 Effect of dilutive securities: Employee stock options 141 99 181 117 Weighted-average shares-diluted 10,851 10,815 10,864 10,832 Income per common share attributable to Alliance HealthCare Services, Inc.: Basic $ 0.37 $ 0.67 $ 0.82 $ 0.65 Diluted $ 0.37 $ 0.67 $ 0.80 $ 0.65 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 338 392 234 379 Average exercise price per share that exceeds average market price of common stock $ 34.74 $ 30.07 $ 37.70 $ 30.35

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies 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 September 30, 2015 , the Company has determined that no liability is necessary related to these guarantees and indemnities. On June 14, 2013, Alliance Oncology, LLC, a subsidiary of the Company, filed a complaint against Harvard Vanguard Medical Associates, Inc. (“HVMA”) in the United States District Court for the District of Massachusetts, including several claims seeking damages resulting from HVMA’s early termination of a long-term services agreement between the two companies. HVMA filed an answer to Alliance Oncology’s complaint on August 27, 2013. Without specifying its alleged damages, HVMA also asserted several counterclaims in its answer. The Company filed its answer to HVMA’s counterclaims on October 4, 2013, and intends to vigorously defend against the claims asserted. The Company has not recorded an expense related to any potential damages in connection with this matter because any potential loss is not probable or reasonably estimable at this time. On February 10, 2015, Alliance Oncology was served with a lawsuit in the United States District Court for the Western District of Missouri by Dr. Barry Michael Driver. At the time the lawsuit was filed, the Plaintiff was an employed physician 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 $1,500 as full release of any and all claims. 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 results of operations, financial position, or cash flows.

Related-Party Transactions

Related-Party Transactions	9 Months Ended
	Sep. 30, 2015
Related Party Transactions [Abstract]
Related-Party Transactions	Related-Party Transactions On April 16, 2007, Oaktree and MTS purchased 4,900,301 shares of the Company’s common stock. Upon completion of the transaction, Oaktree and MTS owned in the aggregate approximately 49.7% of the outstanding shares of common stock of the Company. At September 30, 2015 , Oaktree and MTS owned in the aggregate approximately 50.6% of the outstanding shares of common stock of the Company. The Company does not pay management fees to Oaktree and MTS for their financial advisory services to the Company. On September 16, 2015, Fujian Thai Hot Investment Co., Ltd ("Thai Hot") agreed to purchase 5,537,945 shares of the Company's common stock from funds managed by Oaktree and MTS, and Mr. Buckelew, for $102,452 , or $18.50 per share. Upon completion of the transaction, Thai Hot would own approximately 51.5% of the outstanding common stock of the Company. The Company will not sell any shares in the transaction. The transaction is subject to certain closing conditions, including clearance under the Hart-Scott-Rodina Antitrust Improvements Act of 1976, approval of certain foreign and domestic regulatory filings, consent of the Company's lenders under its term loan and revolving credit facilities, and execution of a governance and standstill agreement between the Company and Thai Hot. Management expects the transaction to close in the fourth quarter of 2015. The Company had direct ownership in two unconsolidated investees at September 30, 2015 and three unconsolidated investees at September 30, 2014. As discussed in Note 2 of the Notes to the Condensed Consolidated Financial Statements, 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. Revenues from management agreements with unconsolidated equity investees were $2,235 and $1,191 during the quarters ended September 30, 2014 and 2015 , respectively. Revenues from management agreements with unconsolidated equity investees were $6,797 and $5,778 during the nine months ended September 30, 2014 and 2015 , respectively. The Company provides services as part of its ongoing operations for and on behalf of the unconsolidated equity investees, which are included in the management agreement revenue, who reimburse the Company for the actual amount of the expenses incurred. The Company records the expenses as cost of revenues and the reimbursement as revenues in its Condensed Consolidated Statements of Income and Comprehensive Income. For the quarters ended September 30, 2014 and 2015 , the amounts of the revenues and expenses were $1,764 and $978 , respectively. For the nine months ended September 30, 2014 and 2015 , the amounts of the revenues and expenses were $5,451 and $4,707 , respectively. Revenues and expenses from AHNI prior to August 1, 2015 have been included in these amounts. The results for AHNI subsequent to August 1, 2015 have been consolidated. 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”). Of the other lenders, Oaktree funded approximately $40,476 of the $340,000 six -year term loan facility. In addition, on July 3, 2013, Oaktree funded approximately $9,524 of the $80,000 delayed draw. On December 2, 2013, the Company borrowed $70,000 of the incremental term loans from its current lenders under its Credit Agreement with Credit Suisse AG, Cayman Islands Branch, as administrative agent. The Company used the proceeds from the transaction plus borrowings under its revolving line of credit and cash on hand to complete the redemption of all its outstanding Notes on December 4, 2013. Oaktree funded $10,000 of the $70,000 incremental term loan. As of September 30, 2015, Oaktree held $53,812 of our term loan facility, including amounts purchased in the open market.

Investments in Unconsolidated I

Investments in Unconsolidated Investees	9 Months Ended
	Sep. 30, 2015
Equity Method Investments and Joint Ventures [Abstract]
Investments in Unconsolidated Investees	Investments in Unconsolidated Investees The Company has direct ownership in two unconsolidated investees at September 30, 2015 . The Company owns between 15% and 50% of these investees, 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 since 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, as such, the Company accounted for the investment using the equity method. During 2014, in accordance with ASC 323, “Investments—Equity Method and Joint Ventures,” the Company wrote off its remaining investment in one of its unconsolidated investees that was originally acquired in 2011. The impairment charge totaled $236 and is related to the closure of one cancer center in the second quarter of 2014 due to the expiration of one of its non-compete agreements with the affiliated oncology physician. Impairment charges related to this event were taken in 2013 for a physician referral network, trademarks, and professional services agreement, which were all written down to zero value. Set forth below are certain balance sheet data for the aggregate of the Company’s unconsolidated investees as of December 31, 2014, and September 30, 2015, including balance sheet data for AHNI as of December 31, 2014: December 31, 2014 September 30, 2015 Balance Sheet Data: Current assets $ 8,687 $ 2,954 Noncurrent assets 10,108 425 Current liabilities 3,760 722 Noncurrent liabilities 3,395 35 Set forth below are certain operating results for the aggregate of the Company’s unconsolidated investees, including the operating results for AHNI from January 1, 2014 through its acquisition on August 1, 2015, for the quarters and nine months ended September 30, 2014 and 2015: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Combined Operating Results: Revenues $ 7,354 $ 3,788 $ 20,550 $ 16,894 Expenses 3,424 1,648 10,169 7,904 Net income 3,930 2,140 10,381 8,990 Earnings from unconsolidated investees 1,219 592 3,459 3,047

Stockholders' Deficit

Stockholders' Deficit	9 Months Ended
	Sep. 30, 2015
Stockholders' Equity Note [Abstract]
Stockholders' Deficit	Stockholders’ Deficit The following table summarizes consolidated stockholders’ deficit, including noncontrolling interest. Stockholders’ Equity (Deficit) Attributable to Additional Accumulated Alliance Total Common Stock Treasury Stock Paid-In Comprehensive Accumulated HealthCare Noncontrolling Stockholders’ Shares Amount Shares Amount Capital Income (Loss) Deficit Services, Inc. Interest Deficit Balance at January 1, 2015 10,713,658 $ 107 (157,973 ) $ (3,138 ) $ 27,653 $ (351 ) $ (194,091 ) $ (169,820 ) $ 58,340 $ (111,480 ) Exercise of stock options 2,515 — — — 25 — — 25 — 25 Purchase of treasury stock — — — — — — — — — — Share-based payment — — — — 1,242 — — 1,242 — 1,242 Share-based payment income tax benefit — — — — (82 ) — — (82 ) — (82 ) Unrealized loss on hedging transaction, net of tax — — — — — (149 ) — (149 ) — (149 ) Net investments in subsidiaries — — — — — — — — 16,683 16,683 Net income — — — — — — 6,994 6,994 15,111 22,105 Balance at September 30, 2015 10,716,173 $ 107 (157,973 ) $ (3,138 ) $ 28,838 $ (500 ) $ (187,097 ) $ (161,790 ) $ 90,134 $ (71,656 )

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Segment Information	Segment Information 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 operating segments, of which two are reportable segments, Radiology and Radiation Oncology, based on similar economic and other characteristics. The Radiology segment is comprised of diagnostic imaging services including MRI, PET/CT and other imaging services. The Radiation Oncology segment is comprised of radiation oncology services. 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, Segment Income and Net Income. The accounting policies of the segments are the same as those described in the summary of significant accounting policies in Note 1 of the Notes to the Consolidated Financial Statements on Form 10-K for the year ended December 31, 2014. Additionally, the Company does not consider its wholesale revenue and retail revenue sources to constitute separate operating segments as discrete financial information does not exist and is not provided to the CODM. The following table summarizes the Company’s revenue by segment: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Revenue Radiology $ 86,587 $ 86,284 $ 258,522 $ 252,665 Radiation Oncology 23,550 25,224 68,218 74,740 Corporate / Other — 9,276 — 21,312 Total $ 110,137 $ 120,784 $ 326,740 $ 348,717 The following are components of revenue: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Revenue MRI $ 45,719 $ 47,603 $ 135,541 $ 135,739 PET/CT 33,542 32,248 101,089 96,392 Radiation Oncology 23,550 25,224 68,218 74,740 Other radiology 7,326 6,433 21,892 20,534 Corporate / Other — 9,276 — 21,312 Total $ 110,137 $ 120,784 $ 326,740 $ 348,717 Segment income represents net income before income taxes; interest expense and other, net; amortization expense; depreciation expense; share-based payment; severance and related costs; noncontrolling interest in subsidiaries; restructuring charges; transaction costs; impairment charges, loss on extinguishment of debt, other nonrecurring charges, and non-cash charges. Segment income is the most frequently used measure of each segment’s performance by the CODM and is commonly used in setting performance goals. The following table summarizes the Company’s segment income (loss): Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Segment income (loss) Radiology $ 32,265 $ 28,526 $ 96,523 $ 83,319 Radiation Oncology 10,910 12,661 31,400 37,005 Corporate / Other (8,222 ) (7,325 ) (23,349 ) (22,331 ) Total $ 34,953 $ 33,862 $ 104,574 $ 97,993 The reconciliation of net income to total segment income is shown below: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Net income attributable to Alliance HealthCare Services, Inc. $ 4,011 $ 7,204 $ 8,727 $ 6,994 Income tax expense 2,948 5,098 6,256 5,304 Interest expense and other, net 6,208 6,660 18,570 19,582 Amortization expense 1,961 2,377 5,870 6,907 Depreciation expense 12,743 12,247 42,812 35,952 Share-based payment (included in selling, general and administrative expenses) 407 423 1,117 1,242 Severance and related costs 455 277 2,315 731 Noncontrolling interest in subsidiaries 3,843 5,861 10,928 15,111 Restructuring charges (Note 2) (264 ) 216 2,191 707 Transaction costs 573 432 1,512 1,964 Impairment charges 4 71 240 6,817 Legal settlements (included in selling, general and administrative expenses) 2,000 2,924 3,621 5,827 Other non-cash charges (included in other income and expense, net) 64 22 415 805 Non-cash gain on step acquisition (included in other income and expense, net) — (9,950 ) — (9,950 ) Total segment income $ 34,953 $ 33,862 $ 104,574 $ 97,993 Net income (loss) for the Radiology and Radiation Oncology segments does not include charges for interest expense, net of interest income, income taxes or certain selling, general and administrative expenses. These costs are charged against the Corporate / Other segment. The following table summarizes the Company’s net income (loss) by segment: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Net income (loss) Radiology $ 21,096 $ 13,283 $ 58,913 $ 48,217 Radiation Oncology 4,534 10,864 12,602 14,259 Corporate / Other (21,619 ) (16,943 ) (62,788 ) (55,482 ) Total $ 4,011 $ 7,204 $ 8,727 $ 6,994 The following table summarizes the Company’s identifiable assets by segment: As of December 31, 2014 As of September 30, 2015 Identifiable assets Radiology $ 229,141 $ 262,833 Radiation Oncology 182,880 182,630 Corporate / Other 88,864 147,771 Total $ 500,885 $ 593,234 The following table summarizes the Company’s goodwill by segment: Radiology Radiation Oncology Corporate / Other Total Balance at January 1, 2014 $ 42,166 $ 14,809 $ — $ 56,975 Goodwill acquired during the period — 6,889 — 6,889 Impairment charges — — — — Adjustments to goodwill during the period — — — — Balance at December 31, 2014 $ 42,166 $ 21,698 $ — $ 63,864 Goodwill acquired during the period 3,342 — 22,611 25,953 Impairment charges — — — — Adjustments to goodwill during the period — — — — Balance at September 30, 2015 $ 45,508 $ 21,698 $ 22,611 $ 89,817 Gross goodwill $ 199,850 $ 41,600 $ 22,611 $ 264,061 Accumulated impairment charges (154,342 ) (19,902 ) — (174,244 ) Balance at September 30, 2015 $ 45,508 $ 21,698 $ 22,611 $ 89,817 The following table summarizes the cash used for capital expenditures for the Radiology, Radiation Oncology and Corporate segments: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Cash used for capital expenditures Radiology $ 6,331 $ 10,075 $ 13,159 $ 25,734 Radiation Oncology 3,051 1,183 3,070 10,394 Corporate / Other 556 450 6,965 3,256

Subsequent Events Subsequent Ev

Subsequent Events Subsequent Events (Notes)	9 Months Ended
	Sep. 30, 2015
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Pacific Cancer Institute On October 15, 2015, the Company executed an agreement to form a partnership between its Radiation Oncology division and the Pacific Cancer Institute ("PCI"), a state-of-the-art radiation therapy and stereotactic radiosurgery center located in Maui, Hawaii, whereby it acquired a 95% controlling interest in PCI. The closing of the transaction is subject to various conditions that are expected to be satisfied during the fourth quarter of 2015. PRC Associates On October 14, 2015, the Company, through its Interventional Partners division, acquired a 60% controlling interest in PRC Associates, LLC, ("PRC"), a premier provider of interventional pain management healthcare with eight locations in Central Florida and the Palm Coast.

Basis of Presentation, Princi23

Basis of Presentation, Principles of Consolidation, and Use of Estimates (Policies)	9 Months Ended
	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared by Alliance HealthCare Services, Inc. (the “Company”) in accordance with accounting principles generally accepted in the United States of America and with the instructions to Form 10-Q and Article 10 of Regulation S-X of the Securities and Exchange Commission. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles (“GAAP”) for complete financial statements. In the opinion of management, all adjustments (including normal recurring accruals) considered necessary for a fair presentation have been included. Operating results for the quarter and nine months ended September 30, 2015 are not necessarily indicative of the results that may be expected for the year ending December 31, 2015 . The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes to the consolidated financial statements for the year ended December 31, 2014 .
Principles of Consolidation	Principles of Consolidation The accompanying unaudited condensed 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 records noncontrolling interest related to its consolidated subsidiaries which are not wholly owned. Investments in unconsolidated investees are accounted for under the equity method.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
Share-based Payment	The Company has adopted ASC 718, “Compensation—Stock Compensation,” and has elected to follow 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.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Revenue Recognition In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU number 2014-09, “Revenue from Contracts with Customers (Topic 606)" to clarify and converge the revenue recognition principles under U.S. GAAP and IFRS 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 adoption of ASU 2014-09 is effective for publicly traded business entities for annual reporting periods beginning after December 15, 2017, including interim reporting periods within that reporting period. Earlier application is not permitted. On April 29, 2015, the FASB proposed a one-year deferral for the effective date of the new standard. The Company is assessing the impact, if any, that the adoption of ASU 2014-09 may have on the Company's results of operations, cash flows, or financial position. Going Concern In August 2014, the FASB issued ASU number 2014-15, "Presentation of Financial Statements—Going Concern (Subtopic 205-40)". Under U.S. 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 Company is assessing the impact, if any, that the adoption of ASU 2014-15 may have on the Company's results of operations, cash flows, or financial position.
Derivatives	The Company accounts for derivative instruments and hedging activities in accordance with the provisions of ASC 815, “Derivatives and Hedging.” Management generally designates derivatives in a hedge relationship with the identified exposure on the date the Company enters into a derivative contract, as disclosed below. The Company has only executed derivative instruments that are economic hedges of exposures that can qualify in hedge relationships under ASC 815. 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 assesses effectiveness of its hedging relationships, both at the hedge inception and on an ongoing basis, then measures and records ineffectiveness. The Company would discontinue hedge accounting prospectively (i) if it is determined that the derivative is no longer effective in offsetting 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, or (iv) 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 their fair value. For additional information please see Note 5 of the Notes to the Condensed Consolidated Financial Statements. For derivatives accounted for as cash flow hedges, any effective unrealized gains or losses on fair value are included in comprehensive income, net of tax, and any ineffective gains or losses are recognized in income immediately. Amounts recorded in comprehensive income are reclassified to earnings when the hedged item impacts earnings.

Transactions (Tables)

Transactions (Tables)	9 Months Ended
	Sep. 30, 2015
Business Combinations, Restructuring and Related Activities [Abstract]
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 amounts of the assets acquired and liabilities assumed recognized at the acquisition date, as well as the fair value at the acquisition date of the noncontrolling interest in AHNI: Consideration: The Company's equity investment in AHNVPS transferred to AHNI $ 690 Certain equipment transferred to AHNI by the Company 477 Fair value of total consideration transferred 1,167 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 9,818 Goodwill $ 3,342
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: Cash received $ 691 Accounts receivable, net 4,440 Equipment, net 3,346 Other assets 416 Goodwill 22,611 Identifiable intangible assets 24,600 Debt (2,781 ) Other liabilities (3,532 ) Noncontrolling interest (20,598 ) Total consideration $ 29,193

Share-Based Payment (Tables)

Share-Based Payment (Tables)	9 Months Ended
	Sep. 30, 2015
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: Nine months ended September 30, 2014 2015 Risk free interest rate 1.83 % 1.65 % Expected dividend yield — % — % Expected stock price volatility 66.3 % 65.2 % Average expected life (in years) 6.00 6.00
Summary of stock option activity	The following table summarizes the Company’s stock option activity: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term Aggregate Intrinsic Value Outstanding at January 1, 2015 633,898 $ 21.39 Granted 83,514 23.91 Exercised (2,515 ) 10.12 Canceled (34,398 ) 50.58 Outstanding at September 30, 2015 680,499 $ 20.28 5.77 $ 1,055 Vested and expected to vest in the future at September 30, 2015 656,162 $ 20.11 5.70 $ 1,055 Exercisable at September 30, 2015 483,502 $ 18.03 4.93 $ 1,052
Summary of unvested stock option activity	The following table summarizes the Company’s unvested stock option activity: Shares Weighted-Average Grant-Date Fair Value Unvested at January 1, 2015 197,899 $ 12.13 Granted 83,514 14.25 Vested (78,825 ) 6.08 Canceled (5,591 ) 15.16 Unvested at September 30, 2015 196,997 $ 15.40
Summary of unvested restricted stock activity	The following table summarizes the Company’s restricted stock activity: Shares Weighted-Average Grant-Date Fair Value Unvested at January 1, 2015 32,959 $ 20.99 Granted to employees — — Granted to non-employee directors — — Vested — — Canceled — — Unvested at September 30, 2015 32,959 $ 20.99

Fair Value of Financial Instr26

Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Estimated fair values of financial instruments	The estimated fair values of the Company’s financial instruments are as follows: December 31, 2014 September 30, 2015 Carrying Value Fair Value Carrying Value Fair Value Cash and cash equivalents $ 33,033 $ 33,033 $ 44,848 $ 44,848 Fixed-rate debt 13,015 13,878 26,874 26,874 Variable-rate debt 494,274 494,354 525,442 525,756 Contingent consideration related to acquisition — — 1,800 1,800 Derivative instruments - asset position 228 228 2 2 Derivative instruments - liability position 46 46 48 48
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 by the above ASC 820 pricing levels as of December 31, 2014: Total Quoted market prices in active markets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Cash and cash equivalents $ 33,033 $ 33,033 $ — $ — Interest rate contracts - asset position 228 228 Interest rate contracts - liability position 46 — 46 — The following table summarizes the valuation of the Company’s financial instruments that are reported at fair value on a recurring basis by the above ASC 820 pricing levels as of September 30, 2015 : Total Quoted market prices in active markets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Cash and cash equivalents $ 44,848 $ 44,848 $ — $ — Contingent consideration related to acquisition 1,800 — — 1,800 Interest rate contracts - asset position 2 — 2 — Interest rate contracts - liability position 48 — 48 —

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in the carrying amount of goodwill	Changes in the carrying amount of goodwill are as follows: Balance at January 1, 2014 $ 56,975 Goodwill acquired during the period 6,889 Impairment charges — Adjustments to goodwill during the period — Balance at December 31, 2014 63,864 Goodwill acquired during the period 25,953 Impairment charges — Adjustments to goodwill during the period — Balance at September 30, 2015 $ 89,817 Gross goodwill $ 264,061 Accumulated impairment charges (174,244 ) Balance at September 30, 2015 $ 89,817
Summary of intangible assets	Intangible assets consisted of the following: December 31, 2014 September 30, 2015 Gross Carrying Amount Accumulated Amortization Intangible Assets, net Gross Carrying Amount Accumulated Amortization Intangible Assets, net Amortizing intangible assets: Customer contracts $ 162,089 $ (93,617 ) $ 68,472 $ 181,116 $ (100,628 ) $ 80,488 Other 26,241 (21,758 ) 4,483 37,341 (21,572 ) 15,769 Total amortizing intangible assets $ 188,330 $ (115,375 ) $ 72,955 $ 218,457 $ (122,200 ) $ 96,257 Intangible assets not subject to amortization 42,975 44,705 Total other intangible assets $ 115,930 $ 140,962
Estimated annual amortization expense	Estimated annual amortization expense for each of the fiscal years ending December 31, is presented below: 2015 $ 9,419 2016 8,418 2017 7,979 2018 7,471 2019 7,098 Thereafter 62,697

Other Accrued Liabilities (Tabl

Other Accrued Liabilities (Tables)	9 Months Ended
	Sep. 30, 2015
Accrued Liabilities, Current [Abstract]
Components of other accrued liabilities	Other accrued liabilities consisted of the following: December 31, 2014 September 30, 2015 Accrued systems rental and maintenance costs $ 1,586 $ 2,160 Accrued site rental fees 992 1,052 Accrued property and sales taxes payable 9,276 9,113 Accrued self-insurance expense 2,276 2,609 Deferred gain on sale of equipment 312 312 Other accrued expenses 12,100 11,442 Total $ 26,542 $ 26,688

Long-Term Debt and Senior Sub29

Long-Term Debt and Senior Subordinated Credit Facility (Tables)	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Components of long-term debt	Long-term debt consisted of the following: December 31, 2014 September 30, 2015 Term loan facility $ 482,825 $ 504,174 Discount on term loan facility (2,156 ) (1,949 ) Revolving credit facility 2,000 — Equipment debt 24,620 50,091 Long-term debt, including current portion 507,289 552,316 Less current portion 15,512 29,915 Long-term debt $ 491,777 $ 522,401

Derivatives (Tables)

Derivatives (Tables)	9 Months Ended
	Sep. 30, 2015
Summary of Derivative Instruments [Abstract]
Effect of designated derivative instruments on the Statement of Operations	The Effect of Designated Derivative Instruments on the Statement of Operations For the Quarter Ended September 30, 2014 Derivatives in Cash Flow Hedging Relationships Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Location of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Amount of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Interest rate contracts $ 80 Interest expense and other, net $ 8 Interest expense and other, net $ 1 The Effect of Designated Derivative Instruments on the Statement of Operations For the Nine Months Ended September 30, 2014 Derivatives in Cash Flow Hedging Relationships Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Location of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Amount of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Interest rate contracts $ (399 ) Interest expense and other, net $ (117 ) Interest expense and other, net $ (1 ) The Effect of Designated Derivative Instruments on the Statement of Operations For the Quarter Ended September 30, 2015 Derivatives in Cash Flow Hedging Relationships Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Location of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Amount of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Interest rate contracts $ (11 ) Interest expense and other, net $ (7 ) Interest expense and other, net $ — The Effect of Designated Derivative Instruments on the Statement of Operations For the Nine Months Ended September 30, 2015 Derivatives in Cash Flow Hedging Relationships Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) Location of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion) Location of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Amount of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion) Interest rate contracts $ (219 ) Interest expense and other, net $ 9 Interest expense and other, net $ 1

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Computation of basic and diluted loss per share	The following table sets forth the computation of basic and diluted earnings per share: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Numerator: Net income attributable to Alliance HealthCare Services, Inc. $ 4,011 $ 7,204 $ 8,727 $ 6,994 Denominator: Weighted-average shares-basic 10,710 10,716 10,683 10,715 Effect of dilutive securities: Employee stock options 141 99 181 117 Weighted-average shares-diluted 10,851 10,815 10,864 10,832 Income per common share attributable to Alliance HealthCare Services, Inc.: Basic $ 0.37 $ 0.67 $ 0.82 $ 0.65 Diluted $ 0.37 $ 0.67 $ 0.80 $ 0.65 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 338 392 234 379 Average exercise price per share that exceeds average market price of common stock $ 34.74 $ 30.07 $ 37.70 $ 30.35

Investments in Unconsolidated32

Investments in Unconsolidated Investees (Tables)	9 Months Ended
	Sep. 30, 2015
Equity Method Investments and Joint Ventures [Abstract]
Schedule of financial data of unconsolidated investees, Balance Sheet Data	Set forth below are certain balance sheet data for the aggregate of the Company’s unconsolidated investees as of December 31, 2014, and September 30, 2015, including balance sheet data for AHNI as of December 31, 2014: December 31, 2014 September 30, 2015 Balance Sheet Data: Current assets $ 8,687 $ 2,954 Noncurrent assets 10,108 425 Current liabilities 3,760 722 Noncurrent liabilities 3,395 35
Schedule of financial data of unconsolidated investees, Combined Operating Results	Set forth below are certain operating results for the aggregate of the Company’s unconsolidated investees, including the operating results for AHNI from January 1, 2014 through its acquisition on August 1, 2015, for the quarters and nine months ended September 30, 2014 and 2015: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Combined Operating Results: Revenues $ 7,354 $ 3,788 $ 20,550 $ 16,894 Expenses 3,424 1,648 10,169 7,904 Net income 3,930 2,140 10,381 8,990 Earnings from unconsolidated investees 1,219 592 3,459 3,047

Stockholders' Deficit (Tables)

Stockholders' Deficit (Tables)	9 Months Ended
	Sep. 30, 2015
Stockholders' Equity Note [Abstract]
Summary of stockholders' deficit, including noncontrolling interest	The following table summarizes consolidated stockholders’ deficit, including noncontrolling interest. Stockholders’ Equity (Deficit) Attributable to Additional Accumulated Alliance Total Common Stock Treasury Stock Paid-In Comprehensive Accumulated HealthCare Noncontrolling Stockholders’ Shares Amount Shares Amount Capital Income (Loss) Deficit Services, Inc. Interest Deficit Balance at January 1, 2015 10,713,658 $ 107 (157,973 ) $ (3,138 ) $ 27,653 $ (351 ) $ (194,091 ) $ (169,820 ) $ 58,340 $ (111,480 ) Exercise of stock options 2,515 — — — 25 — — 25 — 25 Purchase of treasury stock — — — — — — — — — — Share-based payment — — — — 1,242 — — 1,242 — 1,242 Share-based payment income tax benefit — — — — (82 ) — — (82 ) — (82 ) Unrealized loss on hedging transaction, net of tax — — — — — (149 ) — (149 ) — (149 ) Net investments in subsidiaries — — — — — — — — 16,683 16,683 Net income — — — — — — 6,994 6,994 15,111 22,105 Balance at September 30, 2015 10,716,173 $ 107 (157,973 ) $ (3,138 ) $ 28,838 $ (500 ) $ (187,097 ) $ (161,790 ) $ 90,134 $ (71,656 )

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Summary of revenue by segment	The following table summarizes the Company’s revenue by segment: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Revenue Radiology $ 86,587 $ 86,284 $ 258,522 $ 252,665 Radiation Oncology 23,550 25,224 68,218 74,740 Corporate / Other — 9,276 — 21,312 Total $ 110,137 $ 120,784 $ 326,740 $ 348,717 The following are components of revenue: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Revenue MRI $ 45,719 $ 47,603 $ 135,541 $ 135,739 PET/CT 33,542 32,248 101,089 96,392 Radiation Oncology 23,550 25,224 68,218 74,740 Other radiology 7,326 6,433 21,892 20,534 Corporate / Other — 9,276 — 21,312 Total $ 110,137 $ 120,784 $ 326,740 $ 348,717
Summary of segment income	The following table summarizes the Company’s segment income (loss): Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Segment income (loss) Radiology $ 32,265 $ 28,526 $ 96,523 $ 83,319 Radiation Oncology 10,910 12,661 31,400 37,005 Corporate / Other (8,222 ) (7,325 ) (23,349 ) (22,331 ) Total $ 34,953 $ 33,862 $ 104,574 $ 97,993
Reconciliation of net loss to total segment income	The reconciliation of net income to total segment income is shown below: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Net income attributable to Alliance HealthCare Services, Inc. $ 4,011 $ 7,204 $ 8,727 $ 6,994 Income tax expense 2,948 5,098 6,256 5,304 Interest expense and other, net 6,208 6,660 18,570 19,582 Amortization expense 1,961 2,377 5,870 6,907 Depreciation expense 12,743 12,247 42,812 35,952 Share-based payment (included in selling, general and administrative expenses) 407 423 1,117 1,242 Severance and related costs 455 277 2,315 731 Noncontrolling interest in subsidiaries 3,843 5,861 10,928 15,111 Restructuring charges (Note 2) (264 ) 216 2,191 707 Transaction costs 573 432 1,512 1,964 Impairment charges 4 71 240 6,817 Legal settlements (included in selling, general and administrative expenses) 2,000 2,924 3,621 5,827 Other non-cash charges (included in other income and expense, net) 64 22 415 805 Non-cash gain on step acquisition (included in other income and expense, net) — (9,950 ) — (9,950 ) Total segment income $ 34,953 $ 33,862 $ 104,574 $ 97,993
Summary of net income (loss) by segment	The following table summarizes the Company’s net income (loss) by segment: Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Net income (loss) Radiology $ 21,096 $ 13,283 $ 58,913 $ 48,217 Radiation Oncology 4,534 10,864 12,602 14,259 Corporate / Other (21,619 ) (16,943 ) (62,788 ) (55,482 ) Total $ 4,011 $ 7,204 $ 8,727 $ 6,994
Summary of company's identifiable assets by segment	The following table summarizes the Company’s identifiable assets by segment: As of December 31, 2014 As of September 30, 2015 Identifiable assets Radiology $ 229,141 $ 262,833 Radiation Oncology 182,880 182,630 Corporate / Other 88,864 147,771 Total $ 500,885 $ 593,234
Summary of company's goodwill by segment	The following table summarizes the Company’s goodwill by segment: Radiology Radiation Oncology Corporate / Other Total Balance at January 1, 2014 $ 42,166 $ 14,809 $ — $ 56,975 Goodwill acquired during the period — 6,889 — 6,889 Impairment charges — — — — Adjustments to goodwill during the period — — — — Balance at December 31, 2014 $ 42,166 $ 21,698 $ — $ 63,864 Goodwill acquired during the period 3,342 — 22,611 25,953 Impairment charges — — — — Adjustments to goodwill during the period — — — — Balance at September 30, 2015 $ 45,508 $ 21,698 $ 22,611 $ 89,817 Gross goodwill $ 199,850 $ 41,600 $ 22,611 $ 264,061 Accumulated impairment charges (154,342 ) (19,902 ) — (174,244 ) Balance at September 30, 2015 $ 45,508 $ 21,698 $ 22,611 $ 89,817
Schedule of cash used for capital expenditures, by segment	Quarter Ended Nine Months Ended September 30, September 30, 2014 2015 2014 2015 Cash used for capital expenditures Radiology $ 6,331 $ 10,075 $ 13,159 $ 25,734 Radiation Oncology 3,051 1,183 3,070 10,394 Corporate / Other 556 450 6,965 3,256

Transactions - Additional Info

Transactions - Additional Information (Details) $ / shares in Units, $ in Thousands	Feb. 17, 2015USD ($)LocationStages	Sep. 30, 2015USD ($)	Jun. 30, 2014USD ($)	Sep. 30, 2015USD ($)Subsidiaries$ / shares	Sep. 30, 2014USD ($)	Aug. 01, 2015	Jul. 31, 2015	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Nov. 21, 1997	Nov. 20, 1997
Restructuring Cost and Reserve [Line Items]
Restructuring charges				$ 707	$ 2,191
Subsidiaries held prior to acquisition | Subsidiaries				3
Percentage of ownership from investees (percent)						65.50%					46.60%
Non-cash gain on step acquisition		$ 9,950		$ 209	0
Payments to acquire businesses, net of cash				22,657	1,529
Goodwill		$ 89,817		$ 89,817				$ 63,864	$ 56,975
Alliance HNI LLC and Subsidiaries
Restructuring Cost and Reserve [Line Items]
Ownership interest, percentage acquired						15.50%				50.00%
Equity interest in acquiree, percentage		50.00%		50.00%
Useful life				15 years
Capital required for capital adequacy to risk weighted assets		11.50%		11.50%
Revenue multiple				1.7
Non-cash gain on step acquisition				$ 9,950
Cash received		$ 1,848		1,848
Goodwill		3,342		3,342
Identifiable intangible assets		13,700		13,700
Noncontrolling interest, fair value		9,818		9,818
Medical Practice Innovations, Inc.
Restructuring Cost and Reserve [Line Items]
Ownership interest, percentage acquired	50.00%
The Pain Center of Arizona, PC
Restructuring Cost and Reserve [Line Items]
Ownership interest, percentage acquired	59.00%
Useful life	3 years
Number of locations operated by entity | Location	12
Step acquisition, number of stages | Stages	2
Percentage of voting interests acquired before dilution	60.00%
Payments to acquire businesses, net of cash	$ 23,630
Cash received	691
Accounts receivable extinguishment, related parties	3,071
Goodwill	22,611
Identifiable intangible assets	$ 24,600
Weighted average useful life	15 years
Noncontrolling interest, fair value	$ 20,598
Revenue generated by TPC included in results		8,957		20,980
Net income generated by TPC included in results		804		$ 1,095
Contingent consideration performance period				12 months
Contingent consideration related to acquisition		$ 1,800		$ 1,800
Physician referral network intangible assets | The Pain Center of Arizona, PC
Restructuring Cost and Reserve [Line Items]
Identifiable intangible assets	13,500
Trademarks | The Pain Center of Arizona, PC
Restructuring Cost and Reserve [Line Items]
Identifiable intangible assets	$ 11,100
Alliance HNI LLC | Alliance-HNI Leasing Co (AHNIL)
Restructuring Cost and Reserve [Line Items]
Equity interest in acquiree, percentage							98.00%
Alliance HNI LLC | Alliance-HNV PET/CT Services, LLC (AHNVPS)
Restructuring Cost and Reserve [Line Items]
Percentage of ownership from investees (percent)							53.40%
Minimum
Restructuring Cost and Reserve [Line Items]
Percentage of ownership from investees (percent)		15.00%		15.00%
Minimum | Alliance HNI LLC and Subsidiaries
Restructuring Cost and Reserve [Line Items]
Earnings ratio multiple | $ / shares				$ 5
Maximum
Restructuring Cost and Reserve [Line Items]
Percentage of ownership from investees (percent)		50.00%		50.00%
Maximum | Alliance HNI LLC and Subsidiaries
Restructuring Cost and Reserve [Line Items]
Earnings ratio multiple | $ / shares				$ 6.5
Selling, General and Administrative Expenses
Restructuring Cost and Reserve [Line Items]
Restructuring charges				$ 135	1,112
Cost of Revenues Excluding Depreciation and Amortization
Restructuring Cost and Reserve [Line Items]
Restructuring charges				572	$ 1,079
Severance and Related Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 2,315	$ 731
Alliance-HNV PET/CT Services, LLC (AHNVPS)
Restructuring Cost and Reserve [Line Items]
Percentage of ownership from investees (percent)											46.60%

Transactions - Schedule of Bus

Transactions - Schedule of Business Combination, Assets and Liabilities Acquires (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Dec. 31, 2013
Fair Value Inputs, Equity, Quantitative Information [Line Items]
The Company's equity investment in AHNVPS transferred to AHNI	$ 690
Certain equipment transferred to AHNI by the Company	477
Goodwill	89,817	$ 63,864	$ 56,975
Alliance HNI LLC and Subsidiaries
Fair Value Inputs, Equity, Quantitative Information [Line Items]
The Company's equity investment in AHNVPS transferred to AHNI	690
Certain equipment transferred to AHNI by the Company	477
Fair value of total consideration transferred	1,167
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	9,818
Goodwill	$ 3,342

Transactions - Recognized Iden

Transactions - Recognized Identifiable Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Feb. 17, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill	$ 89,817		$ 63,864	$ 56,975
The Pain Center of Arizona, PC
Business Acquisition [Line Items]
Cash received		$ 691
Accounts receivable, net		4,440
Equipment, net		3,346
Other assets		416
Goodwill		22,611
Identifiable intangible assets		24,600
Debt		(2,781)
Other liabilities		(3,532)
Noncontrolling interest		(20,598)
Total consideration		$ 29,193

Share-Based Payment - Weighted

Share-Based Payment - Weighted Average Assumptions for Fair Value of Stock Options (Details)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Weighted average assumptions for stock option awards
Risk free interest rate	1.65%	1.83%
Expected dividend yield	0.00%	0.00%
Expected stock price volatility	65.20%	66.30%
Average expected life	6 years	6 years

Share-Based Payment - Stock Op

Share-Based Payment - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Summary of stock option activity
Begining balance (shares)	633,898
Granted (shares)	83,514
Exercised (shares)	(2,515)	(72,794)
Canceled (shares)	(34,398)
Ending balance (shares)	680,499
Vested and expected to vest (shares)	656,162
Exercisable (shares)	483,502
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Beginning balance, weighted-average exercise price (dollars per share)	$ 21.39
Granted, weighted-average exercise price (dollars per share)	23.91
Exercised, weighted-average exercise price (dollars per share)	10.12
Canceled, weighted-average exercise price (dollars per share)	50.58
Ending balance, weighted-average exercise price (dollars per share)	20.28
Vested and expected to vest, weighted-average exercise price (dollars per share)	20.11
Exercisable, weighted-average exercise price (dollars per share)	$ 18.03
Outstanding, weighted-average remaining contractual term	5 years 9 months 8 days
Vested and expected to vest, weighted-average remaining contractual term	5 years 8 months 12 days
Exercisable, weighted-average remaining contractual term	4 years 11 months 6 days
Outstanding, aggregate intrinsic value	$ 1,055
Vested and expected to vest, aggregate intrinsic value	1,055
Exercisable, aggregate intrinsic value	$ 1,052

Share-Based Payment - Unvested

Share-Based Payment - Unvested Stock Activity (Details)	9 Months Ended
	Sep. 30, 2015$ / sharesshares
Unvested stock option
Summary of unvested stock option activity
Beginning balance, unvested shares (shares)	197,899
Granted, unvested share (shares)	83,514
Vested, unvested share (shares)	(78,825)
Canceled, unvested share (shares)	(5,591)
Ending balance, unvested shares (shares)	196,997
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Beginning balance, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	$ 12.13
Granted, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	14.25
Vested, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	6.08
Canceled, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	15.16
Ending balance, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	$ 15.40
Restricted stock
Summary of unvested stock option activity
Beginning balance, unvested shares (shares)	32,959
Vested, unvested share (shares)	0
Canceled, unvested share (shares)	0
Ending balance, unvested shares (shares)	32,959
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Beginning balance, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	$ 20.99
Vested, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	0
Canceled, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	0
Ending balance, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	$ 20.99
Employees | Restricted stock
Summary of unvested stock option activity
Granted, unvested share (shares)	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Granted, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	$ 0
Non-employee directors | Restricted stock
Summary of unvested stock option activity
Granted, unvested share (shares)	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Granted, unvested shares, weighted-average grant-date fair value (dollars per share) | $ / shares	$ 0

Share-Based Payment - Textual

Share-Based Payment - Textual (Details) - USD ($)	3 Months Ended	9 Months Ended		12 Months Ended			24 Months Ended
	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2015	Nov. 30, 1999
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock shares available for options and awards (shares)		483,341					483,341	2,205,000
Options term		10 years
Options accelerated due to employment agreements vesting (shares)		0		0			0
Weighted average grant date fair value (dollars per share)		$ 14.25	$ 17.56
Exercise of stock options (shares)		2,515	72,794
Total unrecognized fair value related to unvested stock options		$ 1,784,000					$ 1,784,000
Recognized weighted-average period		1 year 10 months 5 days
Total fair value of shares vested		$ 479,000	$ 469,000
Non-Employee Director Serving as Member of Audit Committee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Noninterest expense directors fees				$ 15,000
Non-Employee Director Serving as Chairman of Audit Committee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Noninterest expense directors fees				30,000
Non-Employee Director Serving As Member of Nominating Committee, Compensation Committee, and Strategy and Finance Committee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Noninterest expense directors fees				5,000
Directors' Deferred Compensation Plan | Unaffiliated directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Noninterest expense directors fees		140,000
Fair value of shares issued		140,000
Directors' Deferred Compensation Plan | Non-employee directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Noninterest expense directors fees		$ 40,000		$ 40,000
Time option | 1999 Equity Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Subsequent stock options, vesting after one year		5.00%
Subsequent stock options, vesting after two years		20.00%
Subsequent stock options, vesting after three years		25.00%
Subsequent stock options, vesting after four years		25.00%
Subsequent stock options, vesting after five years		25.00%
Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period					1 year	3 years
Options, typically vesting each year from the date of grant						33.30%
Share-based payment		$ 517,000	$ 511,000
Restricted Stock Awards | Unaffiliated directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period					1 year
Total unrecognized fair value related to unvested stock options		173,000					173,000
Restricted Stock Awards | Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized fair value related to unvested stock options		$ 0					0
Number of awards to non-employees (shares)		0
Restricted Stock Awards | Non-employee directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of awards to non-employees (shares)		0
Restricted Stock Awards | Cliff vest after one year
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period						1 year
Restricted Stock Units (RSUs) | Unaffiliated directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Period in force proceeding grant date		15 days
Restricted Stock Units (RSUs) | Executive Management
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of awards to non-employees (shares)	25,000
Minimum market price that must be achieved		$ 40
Duration of minimum market price		10 days
Restricted Stock Units (RSUs) | Board of Directors Chairman
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of shares issued							$ 138,000
Period after resignation in which entitlement is valid							24 months
Requisite service period							1 year
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		3 years
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years

Fair Value of Financial Instr42

Fair Value of Financial Instruments - Estimated Fair Value of Financial Instruments (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Estimated fair values of financial instruments
Cash and cash equivalents	$ 44,848	$ 33,033
Contingent consideration related to acquisition	1,800
Carrying Value
Estimated fair values of financial instruments
Cash and cash equivalents	44,848	33,033
Fixed-rate debt	26,874	13,015
Variable-rate debt	525,442	494,274
Contingent consideration related to acquisition	1,800	0
Derivative instruments - asset position	2	228
Derivative instruments - liability position	48	46
Fair Value
Estimated fair values of financial instruments
Cash and cash equivalents	44,848	33,033
Fixed-rate debt	26,874	13,878
Variable-rate debt	525,756	494,354
Contingent consideration related to acquisition	1,800	0
Derivative instruments - asset position	2	228
Derivative instruments - liability position	$ 48	$ 46

Fair Value of Financial Instr43

Fair Value of Financial Instruments - Summary of Valuation of Financial Instruments Reported at Fair Value on a Recurring Basis by Pricing Level (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2015	Sep. 30, 2015	Dec. 31, 2014
Radiation Oncology
Financial instruments reported at fair value on a recurring basis
Impairment charges	$ 6,700
Recurring basis
Financial instruments reported at fair value on a recurring basis
Cash and cash equivalents		$ 44,848	$ 33,033
Contingent consideration related to acquisition		1,800
Recurring basis | Interest rate contracts
Financial instruments reported at fair value on a recurring basis
Interest rate contracts - asset position		2	228
Interest rate contracts - liability position		48	46
Recurring basis | Quoted market prices in active markets (Level 1)
Financial instruments reported at fair value on a recurring basis
Cash and cash equivalents		44,848	33,033
Contingent consideration related to acquisition		0
Recurring basis | Quoted market prices in active markets (Level 1) | Interest rate contracts
Financial instruments reported at fair value on a recurring basis
Interest rate contracts - asset position		0
Interest rate contracts - liability position		0	0
Recurring basis | Significant other observable inputs (Level 2)
Financial instruments reported at fair value on a recurring basis
Cash and cash equivalents		0	0
Contingent consideration related to acquisition		0
Recurring basis | Significant other observable inputs (Level 2) | Interest rate contracts
Financial instruments reported at fair value on a recurring basis
Interest rate contracts - asset position			228
Interest rate contracts - liability position		48	46
Recurring basis | Significant unobservable inputs (Level 3)
Financial instruments reported at fair value on a recurring basis
Cash and cash equivalents		0	0
Recurring basis | Significant unobservable inputs (Level 3) | Interest rate contracts
Financial instruments reported at fair value on a recurring basis
Interest rate contracts - asset position		0
Interest rate contracts - liability position		$ 0	$ 0

Goodwill and Intangible Asset44

Goodwill and Intangible Assets - Goodwill Rollforward (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Changes in the Carrying Amount of Goodwill
Beginning balance	$ 63,864	$ 56,975
Goodwill acquired during the period	25,953	6,889
Impairment charges	0	0
Adjustments to goodwill during the period	0	0
Ending balance	89,817	$ 63,864
Gross goodwill	264,061
Accumulated impairment charges	$ (174,244)

Goodwill and Intangible Asset45

Goodwill and Intangible Assets - Components of Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Amortizing intangible assets:
Gross Carrying Amount	$ 218,457	$ 188,330
Accumulated Amortization	(122,200)	(115,375)
Intangible Assets, net	96,257	72,955
Intangible assets not subject to amortization	44,705	42,975
Total other intangible assets	140,962	115,930
Customer contracts
Amortizing intangible assets:
Gross Carrying Amount	181,116	162,089
Accumulated Amortization	(100,628)	(93,617)
Intangible Assets, net	80,488	68,472
Other
Amortizing intangible assets:
Gross Carrying Amount	37,341	26,241
Accumulated Amortization	(21,572)	(21,758)
Intangible Assets, net	$ 15,769	$ 4,483

Goodwill and Intangible Asset46

Goodwill and Intangible Assets - Estimated Annual Amortization Expense (Details) $ in Thousands	Sep. 30, 2015USD ($)
Estimated annual amortization expense
2,015	$ 9,419
2,016	8,418
2,017	7,979
2,018	7,471
2,019	7,098
Thereafter	$ 62,697

Goodwill and Intangible Asset47

Goodwill and Intangible Assets - Textual (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, net	$ 96,257			$ 96,257		$ 72,955
Goodwill and Intangible Assets (Textual) [Abstract]
Amortization expense	2,377		$ 1,961	6,907	$ 5,870
Customer contracts
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, net	80,488			80,488		68,472
Other intangible assets
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, net	$ 15,769			$ 15,769		$ 4,483
Goodwill and Intangible Assets (Textual) [Abstract]
Weighted-average estimated useful life of amortization intangible assets				5 years 2 months 15 days
Radiation Oncology
Goodwill and Intangible Assets (Textual) [Abstract]
Impairment charges		$ 6,700
Minimum | Customer contracts
Goodwill and Intangible Assets (Textual) [Abstract]
Weighted-average estimated useful life of amortization intangible assets				2 years 6 months
Maximum | Customer contracts
Goodwill and Intangible Assets (Textual) [Abstract]
Weighted-average estimated useful life of amortization intangible assets				20 years
Physician referral network intangible assets
Finite-Lived Intangible Assets [Line Items]
Intangible Assets, net							$ 0

Other Accrued Liabilities (Deta

Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Components of other accrued liabilities
Accrued systems rental and maintenance costs	$ 2,160	$ 1,586
Accrued site rental fees	1,052	992
Accrued property and sales taxes payable	9,113	9,276
Accrued self-insurance expense	2,609	2,276
Deferred gain on sale of equipment	312	312
Other accrued expenses	11,442	12,100
Total	$ 26,688	$ 26,542

Long-Term Debt and Senior Sub49

Long-Term Debt and Senior Subordinated Credit Facility - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term debt, including current portion	$ 552,316	$ 507,289
Current portion of long-term debt	29,915	15,512
Long-term debt	522,401	491,777
Term Loan Facility
Debt Instrument [Line Items]
Long-term debt, gross	504,174	482,825
Discount on term loan facility	(1,949)	(2,156)
Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit facility	0	2,000
Equipment Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 50,091	$ 24,620

Long-Term Debt and Senior Sub50

Long-Term Debt and Senior Subordinated Credit Facility - Additional Information (Details)	Oct. 11, 2013USD ($)	Jul. 03, 2013USD ($)	Jun. 03, 2013USD ($)	Jun. 30, 2015USD ($)	Dec. 31, 2013USD ($)	Sep. 30, 2015USD ($)	Sep. 30, 2014USD ($)	Jun. 19, 2015USD ($)	Dec. 02, 2013USD ($)	Dec. 31, 2009	Dec. 31, 2004
Debt Instrument [Line Items]
Repayments of long-term debt						$ 8,651,000	$ 3,675,000
Term Loan Facility | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate			4.25%
Revolving Credit Facility | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate			5.25%
Revolving Credit Facility | Minimum
Debt Instrument [Line Items]
Debt, leverage ratio			0.00375
Revolving Credit Facility | Minimum | LIBOR
Debt Instrument [Line Items]
LIBOR floor			2.00%
Revolving Credit Facility | Maximum
Debt Instrument [Line Items]
Debt, leverage ratio			0.005
New Credit Agreement
Debt Instrument [Line Items]
Ownership percentage of subsidiaries			50.00%
New Credit Agreement | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate			1.00%
Debt description of variable rate basis			one-month LIBOR
New Credit Agreement | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate			0.50%
New Credit Agreement | Term Loan Facility
Debt Instrument [Line Items]
Term loan facility borrowing capacity		$ 340,000,000	$ 340,000,000
Debt term			6 years
Repayments of long-term debt		$ 80,000,000
Revolving credit facility						$ 504,174,000
Actual ratio of consolidated total debt to Consolidated Adjusted EBITDA						4.11
New Credit Agreement | Term Loan Facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate			3.25%
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 | Minimum
Debt Instrument [Line Items]
Covenant ratio of consolidated total debt to Consolidated Adjusted EBITDA, current year						4.30
New Credit Agreement | Term Loan Facility | Maximum
Debt Instrument [Line Items]
Debt, leverage ratio			3.25			4.75
Covenant ratio of consolidated total debt to Consolidated Adjusted EBITDA, current year						4.95
New Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Term loan facility borrowing capacity			$ 50,000,000
Debt term			5 years
Revolving credit facility						$ 0
New Credit Agreement | Revolving Credit Facility | Minimum | LIBOR
Debt Instrument [Line Items]
Debt, leverage ratio			0.03
LIBOR floor			1.00%
New Credit Agreement | Revolving Credit Facility | Minimum | Base Rate
Debt Instrument [Line Items]
Debt, leverage ratio			0.02
New Credit Agreement | Revolving Credit Facility | Maximum | LIBOR
Debt Instrument [Line Items]
Debt, leverage ratio			0.0325
New Credit Agreement | Revolving Credit Facility | Maximum | Base Rate
Debt Instrument [Line Items]
Debt, leverage ratio			0.0225
New Credit Agreement | Letter of Credit
Debt Instrument [Line Items]
Term loan facility borrowing capacity			$ 20,000,000
New Credit Agreement | Uncommitted Incremental Loan Facility
Debt Instrument [Line Items]
Term loan facility borrowing capacity			100,000,000
New Credit Agreement | Delayed Draw
Debt Instrument [Line Items]
Term loan facility borrowing capacity			$ 80,000,000
Required draw period			30 days
Period quarterly amortization payments required			5 years 9 months
Debt instrument, periodic payment			$ 1,050,000
New Credit Agreement | Senior notes
Debt Instrument [Line Items]
Extinguishment of debt, amount			$ 190,000,000
Interest rate, stated percentage										8.25%
New Credit Agreement | Committed Incremental Term Loan
Debt Instrument [Line Items]
Term loan facility borrowing capacity						70,000,000			$ 70,000,000
Debt instrument, periodic payment						1,050,000
New Credit Agreement | Committed Incremental Term Loan | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	3.25%
LIBOR floor	1.00%
New Credit Agreement | Committed Incremental Term Loan | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Senior Notes, 7.25 Percent | Senior notes
Debt Instrument [Line Items]
Interest rate, stated percentage											7.25%
First Amendment to New Credit Agreement | Committed Incremental Term Loan
Debt Instrument [Line Items]
Term loan facility borrowing capacity	$ 70,000,000								$ 70,000,000
Percentage of principal amount funded	99.00%
Debt instrument, periodic payment					$ 1,225,000
Second Amendment to New Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Term loan facility borrowing capacity								$ 50,000
Second Amendment to New Credit Agreement | Committed Incremental Term Loan
Debt Instrument [Line Items]
Term loan facility borrowing capacity								$ 30,000
Percentage of principal amount funded	99.50%
Debt instrument, periodic payment				$ 1,300,000
Debt Assumed from Acquisition of Alliance HNI, LLC and Subsidiaries
Debt Instrument [Line Items]
Notes payable						$ 3,880,000
Stated percentage rate range, minimum						1.75%
Stated percentage rate range, maximum						5.60%
Debt Assumed from Acquisition of Alliance HNI, LLC and Subsidiaries | Line of Credit [Member]
Debt Instrument [Line Items]
Term loan facility borrowing capacity						$ 4,000,000
Revolving credit facility						$ 0
Debt Assumed from Acquisition of Alliance HNI, LLC and Subsidiaries | Line of Credit [Member] | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate						1.50%

Derivatives - Textual (Details

Derivatives - Textual (Details) $ in Thousands	3 Months Ended			9 Months Ended
	Dec. 31, 2013USD ($)Interest_rate_derivative	Jun. 30, 2011Interest_rate_derivative	Mar. 31, 2010USD ($)Interest_rate_derivative	Sep. 30, 2015USD ($)interest_swaps	Sep. 30, 2014USD ($)	Jun. 30, 2015USD ($)	Dec. 31, 2014	Mar. 31, 2013	Dec. 31, 2012
Interest Rate Cash Flow Hedges
Derivative [Line Items]
Variable bank rate debt				$ 259,887	$ 257,769
Variable rate debt as a percent of total debt (percent)				47.10%	51.00%
Expected reclassification from accumulated other comprehensive loss to interest expense and other, net				$ 586
Interest rate cap
Derivative [Line Items]
Derivative, notional amount	$ 250,000
Interest rate agreement, basis spread on variable rate (percent)	2.50%
Paid for cap purchase amortized as interest expense	$ 815
Interest rate cap | Interest Rate Cash Flow Hedges
Derivative [Line Items]
Number of agreements | Interest_rate_derivative	5		3
Maturity			Feb. 1, 2014
Derivative, notional amount			$ 150,000
Interest rate swap
Derivative [Line Items]
Derivative, notional amount						$ 1,433
Interest rate agreement, basis spread on variable rate (percent)							1.34%
Interest rate swap | Interest Rate Cash Flow Hedges
Derivative [Line Items]
Number of agreements | Interest_rate_derivative		2
USR swap one | Interest Rate Cash Flow Hedges
Derivative [Line Items]
Maturity		Oct. 1, 2015
Derivative, notional amount				87
Fixed rate of interest paid by the Company (percent)		5.71%
Recorded interest expense rate		8.71%
Underlying debt interest rate		3.00%
USR swap two | Interest Rate Cash Flow Hedges
Derivative [Line Items]
Maturity		Apr. 1, 2014
Interest rate swap, maturing December 2017
Derivative [Line Items]
Derivative, notional amount				2,457
Fixed rate of interest paid by the Company (percent)									3.75%
Recorded interest expense rate									3.75%
Interest rate agreement, basis spread on variable rate (percent)									2.50%
Interest rate swap, maturing December 2017 | LIBOR
Derivative [Line Items]
Interest rate agreement, basis spread on variable rate (percent)									2.50%
Interest rate swap, maturing April 2018
Derivative [Line Items]
Derivative, notional amount				2,271
Fixed rate of interest paid by the Company (percent)								2.873%
Recorded interest expense rate								2.873%
Interest rate agreement, basis spread on variable rate (percent)								2.00%
Interest rate swap, maturing April 2018 | LIBOR
Derivative [Line Items]
Interest rate agreement, basis spread on variable rate (percent)								2.00%
AHNI swaps
Derivative [Line Items]
Derivative, notional amount				$ 3,639
Number of interest swaps | interest_swaps				8
Fixed interest rate, low range				0.85%
Fixed interest rate, high range				1.17%

Derivatives - Income Statement

Derivatives - Income Statement Impact (Details) - Designated Derivative Instruments - Derivatives in Cash Flow Hedging Relationships - Interest rate contracts - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Effect of Derivative Instruments on Statement of Operations
Amount of Gain (Loss) Recognized in OCI on Derivatives (Effective Portion)	$ (11)	$ 80	$ (219)	$ (399)
Interest expense and other, net
Effect of Derivative Instruments on Statement of Operations
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(7)	8	9	(117)
Amount of Gain (Loss) Recognized in Income on Derivatives (Ineffective Portion)	$ 0	$ 1	$ 1	$ (1)

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Abstract]
Income tax expense	$ 5,098	$ 2,948	$ 5,304	$ 6,256
Income tax benefit (percentage)	41.40%	42.40%	43.10%	41.80%
Net income (loss) attributable to Alliance HealthCare Services, Inc.	$ (7,204)	$ (4,011)	$ (6,994)	$ (8,727)
Unrecognized tax benefits related to various federal and state income tax matters	252		252
Tax-effected amount that would reduce the company's effective income tax rate if recognized	205		205
Accrued interest and penalties related to unrecognized tax benefits	$ 13		$ 13

Earnings Per Common Share (Deta

Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Numerator:
Net income attributable to Alliance HealthCare Services, Inc.	$ 7,204	$ 4,011	$ 6,994	$ 8,727
Denominator:
Weighted-average shares-basic (shares)	10,716	10,710	10,715	10,683
Effect of dilutive securities:
Employee stock options (shares)	99	141	117	181
Weighted-average shares-diluted (shares)	10,815	10,851	10,832	10,864
Income per common share attributable to Alliance HealthCare Services, Inc.:
Basic (dollars per share)	$ 0.67	$ 0.37	$ 0.65	$ 0.82
Diluted (dollars per share)	$ 0.67	$ 0.37	$ 0.65	$ 0.80
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	392	338	379	234
Average exercise price per share that exceeds average market price of common stock (dollars per share)	$ 30.07	$ 34.74	$ 30.35	$ 37.70

Commitments and Contingencies (

Commitments and Contingencies (Details)	Sep. 09, 2015USD ($)	Jun. 14, 2013company	Sep. 30, 2015USD ($)
Loss Contingencies [Line Items]
Liability related to guarantees and indemnities			$ 0
HVMA
Loss Contingencies [Line Items]
Number of companies involved in lawsuit | company		2
Dr. Barry Michael Driver
Loss Contingencies [Line Items]
Settlement amount	$ 1,500,000

Related-Party Transactions (Det

Related-Party Transactions (Details)	Jun. 03, 2013USD ($)	Sep. 30, 2015USD ($)investee	Sep. 30, 2014USD ($)unconsolidated_investee	Sep. 30, 2015USD ($)investee	Sep. 30, 2014USD ($)unconsolidated_investee	Dec. 31, 2015USD ($)$ / sharesshares	Aug. 01, 2015	Dec. 02, 2013USD ($)	Jul. 03, 2013USD ($)	Apr. 16, 2007shares
Related Party Transaction [Line Items]
Number of unconsolidated entities with direct ownership		2	3	2	3
Revenues from management agreements with unconsolidated equity investees		$ 1,191,000	$ 2,235,000	$ 5,778,000	$ 6,797,000
New Credit Agreement | Term Loan Facility
Related Party Transaction [Line Items]
Debt amount funded		504,174,000		504,174,000
Term loan facility borrowing capacity	$ 340,000,000								$ 340,000,000
Debt term	6 years
New Credit Agreement | Delayed Draw
Related Party Transaction [Line Items]
Term loan facility borrowing capacity	$ 80,000,000
New Credit Agreement | Committed Incremental Term Loan
Related Party Transaction [Line Items]
Term loan facility borrowing capacity		70,000,000		70,000,000				$ 70,000,000
Oaktree and MTS
Related Party Transaction [Line Items]
Shares purchased by Oaktree and MTS (shares) | shares										4,900,301
Ownership interest, percentage acquired										49.70%
Oaktree | New Credit Agreement | Term Loan Facility
Related Party Transaction [Line Items]
Debt amount funded	40,476,000
Term loan facility borrowing capacity	$ 340,000,000
Debt term	6 years
Oaktree | New Credit Agreement | Delayed Draw
Related Party Transaction [Line Items]
Debt amount funded									9,524,000
Term loan facility borrowing capacity									$ 80,000,000
Oaktree | New Credit Agreement | Committed Incremental Term Loan
Related Party Transaction [Line Items]
Debt amount funded		53,812,000		53,812,000
Term loan facility borrowing capacity		$ 10,000,000		$ 10,000,000
HNI L.L.C.
Related Party Transaction [Line Items]
Ownership interest, percentage acquired							15.50%
Oaktree and MTS
Related Party Transaction [Line Items]
Ownership interest by parent		50.60%		50.60%
HNI L.L.C.
Related Party Transaction [Line Items]
Ownership interest							65.50%
Scenario, Forecast | Thai Hot
Related Party Transaction [Line Items]
Ownership interest, percentage acquired						51.50%
Number of shares acquired | shares						5,537,945
Consideration transferred						$ 102,452,000
Stock price per share | $ / shares						$ 18.50
Revenues | Unconsolidated Equity Method Investees
Related Party Transaction [Line Items]
Reimbursement of expenses from related parties		$ 978,000	1,764,000	$ 4,707,000	5,451,000
Cost of Revenues Excluding Depreciation and Amortization | Unconsolidated Equity Method Investees
Related Party Transaction [Line Items]
Expenses from transactions with related parties		$ 978,000	$ 1,764,000	$ 4,707,000	$ 5,451,000

Investments in Unconsolidated57

Investments in Unconsolidated Investees - Textual (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2014USD ($)center	Sep. 30, 2015USD ($)investee	Aug. 31, 2015	Aug. 01, 2015	Sep. 30, 2014unconsolidated_investee	Dec. 31, 2013USD ($)	Nov. 20, 1997
Schedule Of Equity Method Investments [Line Items]
Number of unconsolidated entities with direct ownership (investee)		2			3
Percentage of ownership from investees (percent)				65.50%			46.60%
Impairment of equity method investment	$ 236
Number of cancer centers closed | center	1
Intangible assets, net	$ 72,955	$ 96,257
Minimum
Schedule Of Equity Method Investments [Line Items]
Percentage of ownership from investees (percent)		15.00%
Maximum
Schedule Of Equity Method Investments [Line Items]
Percentage of ownership from investees (percent)		50.00%
HNI L.L.C.
Schedule Of Equity Method Investments [Line Items]
Ownership interest, percentage acquired			15.50%
Ownership interest			65.50%
Trademarks
Schedule Of Equity Method Investments [Line Items]
Intangible assets, net						$ 0
Physician referral network intangible assets
Schedule Of Equity Method Investments [Line Items]
Intangible assets, net						0
Service agreements
Schedule Of Equity Method Investments [Line Items]
Intangible assets, net						$ 0

Investments in Unconsolidated58

Investments in Unconsolidated Investees - Balance Sheet Data (Details) - Investments - Equity Method and Joint Ventures - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of financial data of unconsolidated investees, Balance Sheet Data
Current assets	$ 2,954	$ 8,687
Noncurrent assets	425	10,108
Current liabilities	722	3,760
Noncurrent liabilities	$ 35	$ 3,395

Investments in Unconsolidated59

Investments in Unconsolidated Investees - Combined Operating Results (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Schedule of financial data of unconsolidated investees, Combined Operating Results
Earnings from unconsolidated investee	$ 592	$ 1,219	$ 3,047	$ 3,459
Investments - Equity Method and Joint Ventures
Schedule of financial data of unconsolidated investees, Combined Operating Results
Revenues	3,788	7,354	16,894	20,550
Expenses	1,648	3,424	7,904	10,169
Net income	2,140	3,930	8,990	10,381
Earnings from unconsolidated investee	$ 592	$ 1,219	$ 3,047	$ 3,459

Stockholders' Deficit (Details)

Stockholders' Deficit (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance			$ (111,480)
Exercise of stock options (shares)			2,515	72,794
Exercise of stock options			$ 25
Share-based payment			1,242
Share-based payment income tax benefit			(82)
Unrealized loss on hedging transaction, net of tax			(149)
Net investments in subsidiaries			16,683
Net income	$ 13,065	$ 7,854	22,105	$ 19,655
Ending balance	$ (71,656)		$ (71,656)
Common Stock
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance (shares)			10,713,658
Beginning balance			$ 107
Exercise of stock options (shares)			2,515
Ending balance (shares)	10,716,173		10,716,173
Ending balance	$ 107		$ 107
Treasury Stock
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance (shares)			(157,973)
Beginning balance			$ (3,138)
Ending balance (shares)	(157,973)		(157,973)
Ending balance	$ (3,138)		$ (3,138)
Additional Paid-In Capital
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance			27,653
Exercise of stock options			25
Share-based payment			1,242
Share-based payment income tax benefit			(82)
Ending balance	28,838		28,838
Accumulated Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance			(351)
Unrealized loss on hedging transaction, net of tax			(149)
Ending balance	(500)		(500)
Accumulated Deficit
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance			(194,091)
Net income			6,994
Ending balance	(187,097)		(187,097)
Alliance HealthCare Services, Inc.
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance			(169,820)
Exercise of stock options			25
Share-based payment			1,242
Share-based payment income tax benefit			(82)
Unrealized loss on hedging transaction, net of tax			(149)
Net income			6,994
Ending balance	(161,790)		(161,790)
Noncontrolling Interest
Increase (Decrease) in Stockholders' Deficit [Roll Forward]
Beginning balance			58,340
Net investments in subsidiaries			16,683
Net income			15,111
Ending balance	$ 90,134		$ 90,134

Segment Information - Textual

Segment Information - Textual (Details)	9 Months Ended
	Sep. 30, 2015segment
Segment Reporting [Abstract]
Number of operating segments (segment)	3
Number of reportable segments (segment)	2

Segment Information - Revenue

Segment Information - Revenue by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Summary of revenue by segment
Revenue	$ 120,784	$ 110,137	$ 348,717	$ 326,740
Operating Segments | Radiology
Summary of revenue by segment
Revenue	86,284	86,587	252,665	258,522
Operating Segments | Radiation Oncology
Summary of revenue by segment
Revenue	25,224	23,550	74,740	68,218
Operating Segments | Corporate / Other
Summary of revenue by segment
Revenue	$ 9,276	$ 0	$ 21,312	$ 0

Segment Information - Componen

Segment Information - Components of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Summary of components of revenue
Revenue	$ 120,784	$ 110,137	$ 348,717	$ 326,740
Radiology | Operating Segments
Summary of components of revenue
Revenue	86,284	86,587	252,665	258,522
Radiation Oncology | Operating Segments
Summary of components of revenue
Revenue	25,224	23,550	74,740	68,218
Corporate / Other | Operating Segments
Summary of components of revenue
Revenue	9,276	0	21,312	0
MRI | Radiology | Operating Segments
Summary of components of revenue
Revenue	47,603	45,719	135,739	135,541
PET/CT | Radiology | Operating Segments
Summary of components of revenue
Revenue	32,248	33,542	96,392	101,089
Other Radiology Revenue | Radiology | Operating Segments
Summary of components of revenue
Revenue	$ 6,433	$ 7,326	$ 20,534	$ 21,892

Segment Information - Summary

Segment Information - Summary of Segment Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Summary of segment income
Segment income (loss)	$ 33,862	$ 34,953	$ 97,993	$ 104,574
Operating Segments | Radiology
Summary of segment income
Segment income (loss)	28,526	32,265	83,319	96,523
Operating Segments | Radiation Oncology
Summary of segment income
Segment income (loss)	12,661	10,910	37,005	31,400
Operating Segments | Corporate / Other
Summary of segment income
Segment income (loss)	$ (7,325)	$ (8,222)	$ (22,331)	$ (23,349)

Segment Information - Reconcil

Segment Information - Reconciliation of Net Income to Segment Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reconciliation of net income to total segment income
Net income attributable to Alliance HealthCare Services, Inc.	$ 7,204	$ 4,011	$ 6,994	$ 8,727
Income tax expense	5,098	2,948	5,304	6,256
Interest expense and other, net	6,660	6,208	19,582	18,570
Amortization expense	2,377	1,961	6,907	5,870
Depreciation expense	12,247	12,743	35,952	42,812
Severance and related costs	277	455	731	2,315
Noncontrolling interest in subsidiaries	5,861	3,843	15,111	10,928
Restructuring charges			707	2,191
Impairment charges	71	4	6,817	240
Gain on acquisition	(9,950)		(209)	0
Segment Reconciling Items
Reconciliation of net income to total segment income
Income tax expense	5,098	2,948	5,304	6,256
Interest expense and other, net	6,660	6,208	19,582	18,570
Amortization expense	2,377	1,961	6,907	5,870
Depreciation expense	12,247	12,743	35,952	42,812
Share-based payment (included in selling, general and administrative expenses)	423	407	1,242	1,117
Severance and related costs	277	455	731	2,315
Noncontrolling interest in subsidiaries	5,861	3,843	15,111	10,928
Restructuring charges	216	(264)	707	2,191
Transaction costs	432	573	1,964	1,512
Impairment charges	71	4	6,817	240
Legal settlements (included in selling, general and administrative expenses)	2,924	2,000	5,827	3,621
Other non-cash charges (included in other income and expense, net)	22	64	805	415
Gain on acquisition	(9,950)	0	(9,950)	0
Operating Segments
Reconciliation of net income to total segment income
Net income attributable to Alliance HealthCare Services, Inc.	$ 33,862	$ 34,953	$ 97,993	$ 104,574

Segment Information - Summar66

Segment Information - Summary of Net Income (Loss) by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Summary of net income (loss) by segment
Net income attributable to Alliance HealthCare Services, Inc.	$ 7,204	$ 4,011	$ 6,994	$ 8,727
Operating Segments
Summary of net income (loss) by segment
Net income attributable to Alliance HealthCare Services, Inc.	33,862	34,953	97,993	104,574
Operating Segments | Radiology
Summary of net income (loss) by segment
Net income attributable to Alliance HealthCare Services, Inc.	13,283	21,096	48,217	58,913
Operating Segments | Radiation Oncology
Summary of net income (loss) by segment
Net income attributable to Alliance HealthCare Services, Inc.	10,864	4,534	14,259	12,602
Operating Segments | Corporate / Other
Summary of net income (loss) by segment
Net income attributable to Alliance HealthCare Services, Inc.	$ (16,943)	$ (21,619)	$ (55,482)	$ (62,788)

Segment Information - Summar67

Segment Information - Summary of Identifiable Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Summary of Company's identifiable assets by segment
Identifiable assets	$ 593,234	$ 500,885
Operating Segments | Radiology
Summary of Company's identifiable assets by segment
Identifiable assets	262,833	229,141
Operating Segments | Radiation Oncology
Summary of Company's identifiable assets by segment
Identifiable assets	182,630	182,880
Operating Segments | Corporate / Other
Summary of Company's identifiable assets by segment
Identifiable assets	$ 147,771	$ 88,864

Segment Information - Summar68

Segment Information - Summary of Goodwill by Segment (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Summary of goodwill by segment
Beginning balance	$ 63,864	$ 56,975
Goodwill acquired during the period	25,953	6,889
Impairment charges	0	0
Adjustments to goodwill during the period	0	0
Gross goodwill	264,061
Accumulated impairment charges	(174,244)
Ending balance	89,817	63,864
Operating Segments | Radiology
Summary of goodwill by segment
Beginning balance	42,166	42,166
Goodwill acquired during the period	3,342	0
Impairment charges	0	0
Adjustments to goodwill during the period	0	0
Gross goodwill	199,850
Accumulated impairment charges	(154,342)
Ending balance	45,508	42,166
Operating Segments | Radiation Oncology
Summary of goodwill by segment
Beginning balance	21,698	14,809
Goodwill acquired during the period	0	6,889
Impairment charges	0	0
Adjustments to goodwill during the period	0	0
Gross goodwill	41,600
Accumulated impairment charges	(19,902)
Ending balance	21,698	21,698
Operating Segments | Corporate / Other
Summary of goodwill by segment
Beginning balance	0	0
Goodwill acquired during the period	22,611	0
Impairment charges	0	0
Adjustments to goodwill during the period	0	0
Gross goodwill	22,611
Accumulated impairment charges	0
Ending balance	$ 22,611	$ 0

Segment Information - Summar69

Segment Information - Summary of Cash Used for Capital Expenditures by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Cash used for capital expenditures			$ 39,382	$ 23,194
Operating Segments | Radiology
Segment Reporting Information [Line Items]
Cash used for capital expenditures	$ 10,075	$ 6,331	25,734	13,159
Operating Segments | Radiation Oncology
Segment Reporting Information [Line Items]
Cash used for capital expenditures	1,183	3,051	10,394	3,070
Operating Segments | Corporate / Other
Segment Reporting Information [Line Items]
Cash used for capital expenditures	$ 450	$ 556	$ 3,256	$ 6,965

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event - Location	Oct. 14, 2015	Oct. 15, 2015
Pacific Cancer Institute (PCI)
Subsequent Event [Line Items]
Ownership interest, percentage acquired		95.00%
PRC Associates, LLC (PRC)
Subsequent Event [Line Items]
Number of locations acquired	8
Ownership interest, percentage acquired	60.00%