Athenahealth (ATHN) 10-Q 18 Oct 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 16, 2013
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	30-Sep-13
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Trading Symbol	ATHN
Entity Registrant Name	ATHENAHEALTH INC
Entity Central Index Key	1131096
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		37,167,863

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$62,274	$154,988
Short-term investments	0	38,092
Accounts receivable - net	97,417	61,916
Current portion of restricted cash	0	1,357
Deferred tax assets - net	2,134	6,907
Prepaid expenses and other current assets	18,824	10,924
Total current assets	180,649	274,184
Property and equipment - net	203,638	54,035
Capitalized software costs - net	26,912	16,050
Purchased intangible assets - net	174,165	21,561
Goodwill	196,183	48,090
Deferred tax assets - net	0	11,759
Investments and other assets	6,670	2,773
Total assets	788,217	428,452
Current liabilities:
Line of credit	50,000	0
Current portion of long-term debt	15,000	0
Accounts payable	11,302	1,733
Accrued compensation	40,364	36,393
Accrued expenses	25,134	19,683
Current portion of deferred revenue	33,623	8,209
Current portion of deferred rent	100	799
Total current liabilities	175,523	66,817
Deferred rent, net of current portion	1,294	2,854
Long-term debt, net of current portion	177,500	0
Deferred revenue, net of current portion	52,631	45,515
Long-term deferred tax liability - net	17,729	0
Other long-term liabilities	5,181	1,618
Total liabilities	429,858	116,804
Commitments and contingencies (note 7)
Stockholders’ equity:
Preferred stock, $0.01 par value: 5,000 shares authorized; no shares issued and outstanding at September 30, 2013 and December 31, 2012, respectively	0	0
Common stock, $0.01 par value: 125,000 shares authorized; 38,422 shares issued and 37,144 shares outstanding at September 30, 2013; 37,572 shares issued and 36,294 shares outstanding at December 31, 2012	385	376
Additional paid-in capital	360,869	303,547
Treasury stock, at cost, 1,278 shares	-1,200	-1,200
Accumulated other comprehensive loss	-150	-81
Retained (accumulated deficit) earnings	-1,545	9,006
Total stockholders’ equity	358,359	311,648
Total liabilities and stockholders’ equity	$788,217	$428,452

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Preferred stock, par value (dollars per share)	$0.01	$0.01
Preferred stock, shares authorized (shares)	5,000,000	5,000,000
Preferred stock, shares issued (shares)	0	0
Preferred stock, shares outstanding (shares)	0	0
Common stock, par value (dollars per share)	$0.01	$0.01
Common stock, shares authorized (shares)	125,000,000	125,000,000
Common stock, shares issued (shares)	38,422,000	37,572,000
Common stock, shares outstanding (shares)	37,144,000	36,294,000
Treasury stock, shares (shares)	1,278,000	1,278,000

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenue:
Business services	$141,326	$102,256	$400,708	$295,915
Implementation and other	10,201	3,630	22,716	10,052
Total revenue	151,527	105,886	423,424	305,967
Expense:
Direct operating	63,245	41,866	175,820	121,678
Selling and marketing	37,584	25,603	111,541	76,720
Research and development	15,104	8,746	41,317	24,529
General and administrative	21,690	11,913	77,437	42,073
Depreciation and amortization	11,263	6,683	30,711	17,964
Total expense	148,886	94,811	436,826	282,964
Operating income (loss)	2,641	11,075	-13,402	23,003
Other (expense) income:
Interest expense	-1,421	-88	-2,586	-264
Other income	30	176	147	498
Total other (expense) income	-1,391	88	-2,439	234
Income (loss) before income tax (provision) benefit	1,250	11,163	-15,841	23,237
Income tax (provision) benefit	-80	-4,953	5,290	-10,445
Net income (loss)	$1,170	$6,210	($10,551)	$12,792
Net income (loss) per share - Basic (in dollars per share)	$0.03	$0.17	($0.29)	$0.36
Net income (loss) per share - Diluted (in dollars per share)	$0.03	$0.17	($0.29)	$0.35
Weighted average shares used in computing net income (loss) per share:
Basic (shares)	36,970	35,832	36,722	35,847
Diluted (shares)	38,343	37,212	36,722	37,038

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net income (loss)	$1,170	$6,210	($10,551)	$12,792
Other comprehensive income (loss):
Unrealized gain on securities, net of tax of $0 and $10 for the three and nine months ended September 30, 2013 and 2012, respectively	0	9	20	47
Unrealized loss on change in fair value of interest rate swap, net of tax of $156 and $0 for the three and nine months ended September 30, 2013 and 2012, respectively	-234	0	-234	0
Foreign currency translation adjustment	292	79	147	58
Total other comprehensive income (loss)	58	88	-67	105
Comprehensive income (loss)	$1,228	$6,298	($10,618)	$12,897

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Unrealized gain (loss) on securities, tax	$0	$10	$0	$10
Unrealized (loss) gain on change in fair value of interest rate swap, tax	$156	$0	$156	$0

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	($10,551)	$12,792
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	43,674	20,341
Amortization of premium on investments	84	1,011
Provision for uncollectible accounts	771	188
Excess tax benefit from stock-based awards	0	-11,310
Deferred income tax	-5,395	-1,263
Change in fair value of contingent considerations	-76	4,785
Stock-based compensation expense	33,725	20,518
Other reconciling adjustments	232	-142
Changes in operating assets and liabilities:
Accounts receivable	-13,128	-4,462
Prepaid expenses and other current assets	-4,322	4,774
Other long-term assets	600	206
Accounts payable	7,401	1,625
Accrued expenses	1,004	1,639
Accrued compensation	1,949	3,373
Deferred revenue	2,342	2,364
Deferred rent	-2,259	-689
Net cash provided by operating activities	56,203	46,180
CASH FLOWS FROM INVESTING ACTIVITIES:
Capitalized software development costs	-21,320	-10,658
Purchases of property and equipment	-21,405	-19,126
Proceeds from sales and maturities of investments	56,245	72,434
Purchases of investments	-2,000	-62,689
Payments on acquisitions, net of cash acquired	-410,161	0
Decrease in restricted cash	1,357	4,151
Other investing activities	0	172
Net cash used in investing activities	-397,284	-15,716
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock under stock plans and warrants	25,139	17,969
Taxes paid related to net share settlement of restricted stock units	-11,093	-3,686
Excess tax benefit from stock-based awards	0	11,310
Payment of contingent consideration accrued at acquisition date	-525	-1,550
Debt issuance costs	-1,699	0
Net settlement of acquired company’s board of directors equity shares	-5,806	0
Proceeds from long-term debt	200,000	0
Proceeds from line of credit	155,000	0
Payments on line of credit	105,000	0
Payments on long-term debt	-7,500	0
Net cash provided by financing activities	248,516	24,043
Effects of exchange rate changes on cash and cash equivalents	-149	26
Net (decrease) increase in cash and cash equivalents	-92,714	54,533
Cash and cash equivalents at beginning of period	154,988	57,781
Cash and cash equivalents at end of period	62,274	112,314
Non-cash transactions
Property, equipment and purchased software recorded in accounts payable and accrued expenses	1,196	2,908
Tax benefit recorded in prepaid expenses and other current assets		11,247
Fair value of equity awards assumed	13,028	0
Additional disclosures
Cash received for interest	451	1,360
Cash paid for interest	1,990	0
Cash paid for taxes	$1,273	$3,869

BASIS_OF_PRESENTATION

BASIS OF PRESENTATION	9 Months Ended
	Sep. 30, 2013
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 athenahealth, Inc. (“athenahealth” or “we”) in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial reporting and as required by Regulation S-X, Rule 10-01. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of our management, the accompanying unaudited condensed consolidated financial statements contain all adjustments (consisting of items of a normal and recurring nature) necessary to present fairly the financial position as of September 30, 2013, and the results of operations and cash flows for the nine month period ended September 30, 2013 and 2012. The results of operations for the nine month period ended September 30, 2013 are not necessarily indicative of the results to be expected for the full year. When preparing financial statements in conformity with GAAP, we must make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates.
	We consider events or transactions that occur after the balance sheet date but before the financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. Subsequent events have been evaluated through the date of issuance of these financial statements. The accompanying unaudited condensed consolidated financial statements and notes thereto should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2012, included in our Annual Report on Form 10-K, which was filed with the Securities and Exchange Commission (“SEC”) on February 11, 2013.
	Segment Reporting – We disclose information about our operating segments based on the way that management organizes the segments within athenahealth for making operating decisions and assessing financial performance. Operating segments are identified as components of an enterprise about which separate discrete financial information is evaluated by the chief operating decision-maker (“CODM”), or decision-making group, in making decisions regarding resource allocation and assessing performance. We are in the process of analyzing the information that will be prepared and presented to the CODM due to the acquisitions of Epocrates, Inc. (“Epocrates”) and the Arsenal on the Charles during the nine months ended September 30, 2013 (see Note 2 Acquisitions). We anticipate that we will have at least two operating segments – athenahealth and Epocrates. Historically, we have operated in one segment.
	Interim Tax Estimate – Due to the fact that we are projecting a nominal pre-tax income (loss) for the year and have significant permanent differences, we cannot reasonably predict our estimated effective tax rate for the year; therefore, we have used a discrete tax approach in calculating the year-to-date provision for the period ended September 30, 2013.
	Related Party Transaction – During the three months ended September 30, 2013, we made an investment in a vendor. The total expense for the three month period ended September 30, 2013, was $0.4 million and the total amount payable at September 30, 2013 was $0.1 million.

ACQUISITIONS

ACQUISITIONS	9 Months Ended
	Sep. 30, 2013
Business Combinations [Abstract]
ACQUISITIONS	ACQUISITIONS
	Watertown, MA Corporate Headquarters – the Arsenal on the Charles
	On May 10, 2013, athenahealth, through its wholly-owned subsidiary Athena Arsenal, LLC, completed the acquisition of the real estate commonly known as the Arsenal on the Charles, located in Watertown, Massachusetts. The Arsenal on the Charles is an expansive 29-acre, multi-building, commercial property where we were leasing space for our headquarters and related operating activities prior to the transaction. The purpose of this acquisition is to allow for future expansion of the corporate headquarters to accommodate anticipated headcount growth. The purchase price was $168.5 million, subject to working capital adjustments. The fair value of the consideration paid was $167.3 million, all of which was paid in cash.
	The following table summarizes the estimated fair values of assets acquired and liabilities assumed as of the date of acquisition:
	Prepaid expenses and other current assets	$	685
	Property, equipment and buildings	144,071
	Purchased intangible assets	25,545
	Accrued expenses	(271		)
	Deferred revenue	(789		)
	Other long-term liabilities	(1,916		)
	Total identifiable net assets	$	167,325
	The fair values assigned to tangible and identifiable intangible assets acquired and liabilities assumed are based on management’s estimates and assumptions and are based on the information that was available as of the date of the acquisition. We believe that the information provides a reasonable basis for estimating the fair values of assets acquired and liabilities assumed, but certain items such as the value of the purchased tangible and intangible assets and certain working capital adjustments to the purchase price may be subject to change as additional information is received about facts and circumstances that existed at the date of acquisition. Thus, the provisional measurements of fair value set forth above are subject to change. We expect to finalize the valuation as soon as practicable, but not later than one year from the acquisition date.
	The following table sets forth the fair value of the preliminary components of the identifiable intangible assets acquired by asset class:
	Above market leases		$	3,298
	In-place leases		22,247
	Total intangible assets subject to amortization		$	25,545
	The value of any in-place lease is estimated to be equal to the property owners’ avoidance of costs necessary to release the property for a lease term equal to the remaining primary in-place lease term and the value of investment grade tenancy. The cost avoidance to the property owners of vacancy/leasing costs necessary to lease the property for a lease term equal to the remaining in-place lease term is derived first by determining the in-place lease term on the subject lease. Then, based on our review of the market, the cost to be borne by a property owner to replicate a market lease to the remaining in-place term was estimated. These costs consist of: (i) rent lost during downtime (e.g., assumed periods of vacancy), (ii) estimated expenses that would be incurred by the property owner during periods of vacancy, (iii) rent concessions (e.g., free rent), (iv) leasing commissions, and (v) tenant improvement allowances. We determine these values using our own estimates along with third-party appraisals. We amortize the capitalized value of in-place lease intangible assets to expense over the remaining initial term of each lease. We amortize the capitalized value of above market leases to expense over the initial and expected renewal terms of the leases. No amortization period for intangible assets will exceed the remaining depreciable life of the building.
	The amounts of third-party tenant revenue (included in the line item "Implementation and other") and net loss from the Arsenal on the Charles included in our condensed consolidated statements of income from the acquisition date of May 10, 2013, through the period ended September 30, 2013, are $6.1 million and $0.2 million, respectively. Direct operating expense from the acquisition date of May 10, 2013, through the period ended September 30, 2013, includes $5.9 million of costs associated with third-party tenant revenue for the Arsenal on the Charles.
	We incurred transaction costs in connection with the acquisition of $2.4 million during the nine months ended September 30, 2013, respectively, and $3.1 million in total. These costs are included in general and administrative expenses.
	Epocrates, Inc.
	On March 12, 2013, we acquired Epocrates, a leading provider of essential clinical content, practice tools, and health industry engagement via mobile devices at the point of care. We acquired Epocrates for the assembled workforce, expected synergies, and accelerated awareness of athenahealth’s services across the physician market and to deliver high-value information to the clinical community. The acquisition date fair value of the consideration transferred for Epocrates, less cash and short-term investments acquired was approximately $237.6 million, which consisted of the following:
	Cash payments	$	294,632
	Fair value of vested stock options and restricted stock units assumed	13,028
	Fair value of total consideration	307,660
	Less cash acquired	(51,796		)
	Less short-term investments acquired	(18,250		)
	Total	$	237,614
	The value of the share consideration for Epocrates’ common stock was based on the average closing sales prices per share of athenahealth common stock for the ten trading days ending on the second trading day prior to the closing of the acquisition. The fair value of the stock options and restricted stock units assumed by us was determined using the Black-Scholes option pricing model. The share conversion ratio of 0.1239 was applied to convert Epocrates stock options and restricted stock units to athenahealth stock options and restricted stock units.
	We assumed stock options and restricted stock units with a fair value of $22.6 million. Of the total consideration, $13.0 million was allocated to the purchase consideration and $9.6 million was allocated to future services and will be expensed over the remaining service periods on a straight-line basis over the remaining service period. In the nine months ended September 30, 2013, stock-based compensation expense recognized for stock options and restricted stock units assumed was $7.6 million.
	The following table summarizes the estimated fair values of assets acquired and liabilities assumed as of the date of acquisition:
	Accounts receivable	$	23,144
	Other current and long-term assets	3,833
	Property, equipment and capitalized software costs	4,168
	Purchased intangible assets	139,900
	Current liabilities	(11,054		)
	Deferred tax liabilities, net	(39,811		)
	Deferred revenue	(29,400		)
	Other long-term liabilities	(1,259		)
	Total identifiable net assets	$	89,521
	Goodwill	148,093
		$	237,614
	The excess of purchase consideration over the fair value of net tangible and identifiable intangible assets acquired was recorded as goodwill. The fair values assigned to tangible and identifiable intangible assets acquired and liabilities assumed were based on management’s estimates and assumptions based on the information that was available as of the date of the acquisition. We believe that the information provides a reasonable basis for estimating the fair values of assets acquired and liabilities assumed, but certain items such as accounts receivable, purchased intangible assets, current and non-current income taxes payable, deferred taxes, deferred revenue and uncertain tax benefits may be subject to change as additional information is received about facts and circumstances that existed at the date of acquisition and certain tax returns are finalized. Thus, the provisional measurements of fair value set forth above are subject to change. We expect to finalize the valuation as soon as practicable, but not later than one year from the acquisition date.
	The following table sets forth the preliminary components of the identifiable intangible assets acquired by asset class and their preliminary estimated useful lives as of the date of acquisition:
		Fair Value			Useful Life
	Physician network	$	104,500		14 years
	Drug information content	10,000			5 years
	Trade name	11,500			10 years
	Customer backlog	2,900			1.5 years
	Epocrates non-compete agreement	4,500			1.5 years
	Developed technology	6,500			3 years
	Total intangible assets subject to amortization	$	139,900
	We anticipate that we will allocate the acquired physician network among our operating segments once determined. The Epocrates segment will represent the fair values of the underlying relationships and agreements with Epocrates customers. The physician network related to the athenahealth segment will represent the fair values of the savings associated with future marketing spend for the athenahealth segment services to the acquired physician network. Drug information content represents the fair value of the cost to replace the drug information and interaction content used by the physician’s network. The trade name represents the fair value of the brand and name recognition associated with the marketing of Epocrates’ service offerings. Customer backlog represents the estimated fair value of existing contractual backlog orders as of the acquisition date. Epocrates non-compete agreement represents the estimated fair value of the contract between athenahealth and a former member of Epocrates management. Developed technology represents the estimated fair value of Epocrates’ mobile device platform. All of the purchased intangible assets related to the Epocrates transaction have finite lives. For those purchased intangible assets where an income approach was used, we considered the projected undiscounted cash flows as the best indication of the pattern of economic benefit expected from each asset.
	The goodwill balance is primarily attributed to the assembled workforce and expanded market opportunities when integrating Epocrates’ mobile device platform with the athenahealth service offerings. We anticipate goodwill will be allocated among our reporting units and operating segments once determined. The goodwill balance is not deductible for U.S. income tax purposes.
	The amounts of revenue and net loss of Epocrates included in our condensed consolidated statements of income from the acquisition date of March 12, 2013, through the period ended September 30, 2013, are $33.5 million and $17.6 million, respectively. The net loss includes $7.6 million in stock-based compensation expense primarily related to the acceleration of certain individuals’ stock awards upon termination.
	We incurred transaction costs in connection with the acquisition of $0.0 million and $2.7 million during the three and nine months ended September 30, 2013, respectively, and $3.2 million in total. These costs are included in general and administrative expenses.
	As part of the integration of Epocrates, we communicated to certain employees severance and retention bonuses which total $4.2 million to be paid through the end of 2013. The following table summarizes these amounts on the condensed consolidated statements of income for the nine months ended September 30, 2013:
	Summary of roll forward of integration costs
	Beginning balance, January 1, 2013	$	—
	Addition to provision	2,209
	Cash payments	(195		)
	Ending balance, March 31, 2013	$	2,014
	Addition to provision	979
	Change in estimate	(129		)
	Cash payments	(1,122		)
Ending balance, June 30, 2013	$	1,742
Addition to provision	526
Change in estimate	(72		)
Cash payments	(692		)
Ending balance, September 30, 2013	$	1,504
Pro Forma Presentation
The following pro forma financial information summarizes the combined results of operations for athenahealth as though the acquisitions of Epocrates and the Arsenal on the Charles occurred on January 1, 2012. The unaudited pro forma financial information is as follows:
	Three months ended September 30,					Nine months ended September 30,
	2013			2012		2013			2012
Revenue	$	151,527		$	132,833	$	443,196		$	390,673
Net income (loss)	$	1,170		$	982	$	(14,953	)	$	(9,101	)
Net income (loss) per share – Basic	$	0.03		$	0.03	$	(0.41	)	$	(0.25	)
Net income (loss) per share – Diluted	$	0.03		$	0.03	$	(0.41	)	$	(0.24	)
The pro forma financial information for all periods presented has been calculated after adjusting the results of Epocrates and the Arsenal on the Charles to reflect the business combination accounting effects resulting from these acquisitions including the amortization expenses from acquired intangible assets, the deprecation expenses from acquired tangible assets, the stock-based compensation expense for unvested stock options and restricted stock units assumed and the related tax effects as though the acquisition occurred as of January 1, 2012. The pro forma financial information is for informational purposes only and is not indicative of the results of operations that would have been achieved if the acquisition had taken place at the beginning of our 2012 fiscal year.

NET_INCOME_LOSS_PER_SHARE

NET INCOME (LOSS) PER SHARE	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]
NET INCOME (LOSS) PER SHARE	NET INCOME (LOSS) PER SHARE
	Basic net income (loss) per share is computed by dividing net income (loss) by the weighted average number of common shares outstanding during the period. Diluted net income (loss) per share is computed by dividing net income (loss) by the weighted average number of common shares outstanding and potentially dilutive securities outstanding during the period under the treasury stock method. Potentially dilutive securities include stock options, restricted stock units, and shares to be purchased under the employee stock purchase plan. Under the treasury stock method, dilutive securities are assumed to be exercised at the beginning of the period and as if funds obtained thereby were used to purchase common stock at the average market price during the period. Securities are excluded from the computations of diluted net income per share if their effect would be anti-dilutive to earnings per share.
	The following table reconciles the weighted average shares outstanding for basic and diluted net income (loss) per share for the periods indicated:
		Three Months Ended September 30,				Nine Months Ended September 30,
		2013		2012		2013			2012
	Net income (loss)	$	1,170	$	6,210	$	(10,551	)	$	12,792
	Weighted average shares used in computing basic net income (loss) per share	36,970		35,832		36,722			35,847
	Net income (loss) per share – Basic	$	0.03	$	0.17	$	(0.29	)	$	0.36
	Net income (loss)	$	1,170	$	6,210	$	(10,551	)	$	12,792
	Weighted average shares used in computing basic net income (loss) per share	36,970		35,832		36,722			35,847
	Effect of dilutive securities	1,373		1,380		—			1,191
	Weighted average shares used in computing diluted net income (loss) per share	38,343		37,212		36,722			37,038
	Net income (loss) per share – Diluted	$	0.03	$	0.17	$	(0.29	)	$	0.35
	The computation of diluted net income per share does not include 0.3 million of stock options and restricted stock units for the three months ended September 30, 2013, because their inclusion would have an anti-dilutive effect on net income per share. The computation of diluted net income per share does not include 0.4 million and 0.4 million of stock options and restricted stock units for the three and nine months ended September 30, 2012, respectively, because their inclusion would have an anti-dilutive effect on net income per share. For the nine months ended September 30, 2013, there were 3.5 million stock options and restricted stock units excluded from the calculation of the diluted net income (loss) per share, since to include them would be anti-dilutive.

FAIR_VALUE_OF_FINANCIAL_INSTRU

FAIR VALUE OF FINANCIAL INSTRUMENTS	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]
FAIR VALUE OF FINANCIAL INSTRUMENTS	FAIR VALUE OF FINANCIAL INSTRUMENTS
	As of September 30, 2013, and December 31, 2012, the carrying amounts of cash and cash equivalents, restricted cash, receivables, accounts payable and accrued expenses approximated their estimated fair values because of the short-term nature of these financial instruments. Included in cash and cash equivalents as of September 30, 2013 and December 31, 2012, are money market fund investments of less than $0.1 million and $59.4 million, respectively, which are reported at fair value. As of September 30, 2013, we had $192.5 million outstanding on its term loan facility and $50 million outstanding on its revolving credit facility (see Note 6. Debt) which approximate their fair values due to their variable rate nature at current market rates. As of December 31, 2012, we had no outstanding debt.
	The following table presents information about our financial assets and liabilities that are measured at fair value on a recurring basis as of September 30, 2013, and December 31, 2012, and indicates the fair value hierarchy of the valuation techniques we utilized to determine such fair value. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities and fair values determined by Level 2 inputs utilize quoted prices (unadjusted) in active markets for similar assets or liabilities. The fair values determined by Level 3 inputs are unobservable values which are supported by little or no market activity.
		Fair Value Measurements At September 30, 2013, Using
		Level 1			Level 2			Level 3			Total
	Cash and cash equivalents:
	Money market funds	$	37		$	—		$	—		$	37
	Total assets	$	37		$	—		$	—		$	37
	Interest rate swap liability	$	—		$	(390	)	$	—		$	(390	)
	Total liabilities	$	—		$	(390	)	$	—		$	(390	)
		Fair Value Measurements as of December 31, 2012, Using
		Level 1			Level 2			Level 3			Total
	Cash and cash equivalents:
	Money market funds	$	89,480		$	—		$	—		$	89,480
	Available-for-sale investments:
	Commercial paper	—			11,748			—			11,748
	Corporate bonds	—			20,334			—			20,334
	Certificate of deposit	—			6,010			—			6,010
	Total assets	$	89,480		$	38,092		$	—		$	127,572
	Accrued contingent consideration	$	—		$	—		$	(448	)	$	(448	)
	Total liabilities	$	—		$	—		$	(448	)	$	(448	)
	Money market funds, certificates of deposit, corporate bonds and commercial paper are valued using a market approach based upon the quoted market prices of identical instruments when available or other observable inputs such as trading prices of identical instruments in inactive markets or similar securities. It is our policy to recognize transfers between levels of the fair value hierarchy, if any, at the end of the reporting period; however, there have been no such transfers during any periods presented. The estimated fair value of our interest rate swap agreement with certain financial institutions at September 30, 2013, was $0.4 million, based on inputs other than quoted prices that are observable for the interest rate swap (Level 2). There was no interest rate swap agreement at December 31, 2012.
	Contingent consideration is recorded at fair value as an element of consideration paid with subsequent adjustments recognized in the consolidated statement of income. At the acquisition date and through the end of the measurement period, the fair value of the accrued contingent consideration was determined using a probability-weighted income approach based on upside, downside and base case scenarios. This approach is based on significant inputs that are not observable in the market, which are referred to as Level 3 inputs. The contingent consideration related to our acquisition of Proxsys in 2011 ranged from zero to $5.0 million and was payable in quarterly installments based upon the cross-selling of our athenaCollector services into Proxsys’ new and acquired customer and physician sender base, from the acquisition date to the second year anniversary of the acquisition in the third quarter of 2013. As of December 31, 2012, we had a probability adjusted level of 60% for the base case and 20% for the upside and downside scenarios. We estimated the fair value of the contingent consideration at December 31, 2012, to be $0.4 million, primarily related to how much had been earned and the amount of time left to earn the additional consideration. We accrued an additional general and administrative expense of $0.1 million during the three and nine months ended September 30, 2013, for the final payment based on the final cross-selling results. We paid $0.5 million related to the second contingent consideration during September 2013. As of September 30, 2013, there are no contingent consideration arrangements owed or outstanding.
	The reconciliations for the fair values of financial instruments determined by Level 3 inputs for the periods presented are as follows:
		Three Months Ended September 30,						Nine Months Ended September 30,
		2013			2012			2013			2012
	Balance, beginning of period	$	448		$	6,259		$	448		$	8,176
	Payments	(524		)	(1,843		)	(524		)	(2,650		)
	Change in fair value (included in general and administrative expenses)	76			(3,675		)	76			(4,785		)
	Balance, end of period	$	—		$	741		$	—		$	741

PROPERTY_AND_EQUIPMENT

PROPERTY AND EQUIPMENT	9 Months Ended
	Sep. 30, 2013
Property, Plant and Equipment [Abstract]
PROPERTY AND EQUIPMENT	PROPERTY AND EQUIPMENT
	The fair values of the property and equipment acquired as part of the purchase of the Arsenal on the Charles are allocated to buildings, land, and land improvements in the amounts of $121.3 million, $21.0 million, and $1.8 million, respectively.
	Property and equipment consist of the following as of:
		September 30, 2013			December 31, 2012
	Equipment	$	74,358		$	56,078
	Furniture and fixtures	7,709			5,297
	Leasehold improvements	2,756			15,518
	Airplane	3,156			3,156
	Building	136,181			14,644
	Building improvements	18,281			3,500
	Land	23,059			2,035
	Land improvements	2,735			915
	Total property and equipment, at cost	268,235			101,143
	Accumulated depreciation and amortization	(68,156		)	(49,902		)
	Construction in progress	3,559			2,794
	Property and equipment, net	$	203,638		$	54,035
	Depreciation expense on property and equipment was $6.6 million and $4.5 million for the three months ended September 30, 2013, and 2012, respectively. Depreciation expense on property and equipment was $18.3 million and $12.2 million for the nine months ended September 30, 2013, and 2012, respectively.

DEBT

DEBT	9 Months Ended
	Sep. 30, 2013
Debt Disclosure [Abstract]
DEBT	DEBT
	2011 Line of Credit – On October 20, 2011, we entered into a $100.0 million revolving credit agreement (“Revolving Credit Agreement”) with a term of five years. The Revolving Credit Agreement contains certain covenants, including consolidated leverage and minimum fixed charge coverage ratios. The interest rates applicable to revolving loans under the Revolving Credit Agreement are at either (i) the British Bankers Association London Interbank Offered Rate (“LIBOR”) plus an interest margin based on our consolidated leverage ratio, or (ii) the base rate (which is the highest of (a) the bank’s prime rate, (b) the Federal Funds rate plus 0.50%, and (c) one month LIBOR plus 1.00%) plus an interest margin based on our consolidated leverage ratio.
	2013 Commitment Letter – On January 7, 2013, we entered into a commitment letter, pursuant to which Bank of America, N.A. committed to increase its commitment to provide revolving loans under the Revolving Credit Agreement by an amount up to $55 million as a source of funding for the Epocrates transaction (see Note 2 Acquisitions). We were required to pay financing fees of $0.3 million for this commitment.
	On March 11, 2013, we borrowed $155.0 million under the Revolving Credit Agreement as a source of funding for the Epocrates transaction. We repaid $50.0 million of the $155.0 million as of March 31, 2013. All amounts outstanding under the Revolving Credit Agreement were repaid on May 10, 2013, as discussed below.
	2013 Credit Agreement – On May 10, 2013, we entered into a $325 million senior credit facility consisting of a $200 million unsecured term loan facility and a $125 million unsecured revolving credit facility (the “Senior Credit Facility”). We may increase the Senior Credit Facility up to an additional $100 million, subject to certain conditions including obtaining lender commitments. The terms and conditions of the Senior Credit Facility are customary to facilities of this nature. The Senior Credit Facility expires on May 10, 2018, although we may prepay the Senior Credit Facility in whole or in part at any time without premium or penalty, and the unutilized portion of the commitments may be irrevocably reduced or terminated by us in whole or in part without penalty or premium. The Senior Credit Facility contains customary default provisions and certain financial and nonfinancial covenants including limitations on our consolidated leverage ratio and capital expenditures.
	On May 10, 2013, we borrowed $200 million under the unsecured term loan facility and $50 million under the unsecured revolving credit facility of the Senior Credit Facility to refinance existing indebtedness described above, to finance the Arsenal on the Charles acquisition as described in Note 2. Acquisitions, and for working capital and other general corporate purposes. The unsecured term loan facility was payable quarterly starting June 30, 2013, in the amount of $3.75 million each quarter. As of September 30, 2013, we had $192.5 million outstanding on the unsecured term loan facility and $50.0 million outstanding on the unsecured revolving credit facility. As of September 30, 2013, we had $75 million available on the unsecured revolving credit facility.
	Any loan under the Senior Credit Facility will bear interest at the same rates as in the Revolving Credit Agreement. The interest rate for the Senior Credit Facility as of September 30, 2013 was 1.93%.
	We were required to pay financing fees of $1.3 million for the Senior Credit Facility, which are being amortized as interest expense in the condensed consolidated statements of income over the five-year term of the agreement.
	Future principle payments of the unsecured term loan facility at September 30, 2013 are as follows:
		Amount
	Remaining 2013	$	3,750
	2014	15,000
	2015	15,000
	2016	15,000
	2017	15,000
	Thereafter	128,750
	Total	192,500
	Less current portion	15,000
	Long-term portion	$	177,500
	During the quarter ended September 30, 2013, we entered into an interest rate swap agreement designed to fix the variable interest rate payable on $120 million of our outstanding borrowings under the Senior Credit Facility at 0.8396% exclusive of the credit spread under the Senior Credit Facility.
	The interest rate swap agreement was designed to manage exposure to interest rates on our variable rate indebtedness. We recognize all derivatives on our balance sheet at fair value. We have designated our interest rate swap agreement as a cash flow hedge. Changes in the fair value of the interest rate swap are recognized in other comprehensive income (loss) (“OCI”) until the hedged items are recognized in earnings. Hedge ineffectiveness, if any, associated with the interest rate swap will be reported by us in interest expense. There was no ineffectiveness associated with the interest rate swap during the quarter ended September 30, 2013, nor was any amount excluded from ineffectiveness testing.
	The fair value of the interest rate swap recognized in other long-term liabilities and in OCI is as follows (in thousands):
							Fair Value
	Effective Date	Notional Amount		Fixed Rate		Maturity	30-Sep-13			31-Dec-12
	August 31, 2013	120,000		0.8396	%	August 31, 2016	$	(390	)	$	—

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Sep. 30, 2013
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES
	On January 11, 2013, a complaint captioned Bushansky v. Epocrates, Inc., et al., Case No. 519078, was filed in San Mateo County Superior Court (the “Court”) on behalf of a putative class of Epocrates’ shareholders against Epocrates and each member of the Epocrates board of directors. This complaint challenged the proposed merger between Epocrates and one of our wholly owned subsidiaries. On January 25, 2013, a similar complaint was filed in the Court captioned DeJoice v. Epocrates, et al., Case No. 519461. This second complaint made similar allegations against Epocrates and each member of the Epocrates board of directors and included a claim against us for aiding and abetting a breach of fiduciary duty. On January 31, 2013, the Bushansky complaint was amended to include additional allegations. Plaintiffs allege, among other things, that the Epocrates directors breached their fiduciary duties by allegedly agreeing to sell Epocrates at an unfair and inadequate price, failing to take steps to maximize the sale price of Epocrates, and making material omissions to the preliminary proxy statement dated January 25, 2013. The complaints sought to enjoin the merger, other equitable relief, and monetary damages. On March 5, 2013, Epocrates and the plaintiffs signed a memorandum of understanding in which the parties agreed to enter into a stipulation of settlement whereby the plaintiffs and all class members would release all claims related to the merger in exchange for Epocrates filing a supplement to its definitive proxy statement regarding the merger with the SEC, which would include additional disclosures regarding the merger agreement, and an agreement to negotiate in good faith regarding the amount of attorneys’ fees and expenses for which plaintiffs may seek approval from the Court. On October 4, 2013, the Court granted final settlement approval including a grant of fees and expenses in the amount of $335,000 to plaintiffs’ counsel. The settlement has no material impact on the Company’s condensed consolidated financial statements.
	In addition, we are engaged from time to time in certain legal disputes arising in the ordinary course of business, including employment discrimination claims and challenges to our intellectual property. We believe that we have adequate legal defenses and that the likelihood of a loss contingency relating to the ultimate dispositions of any of these disputes is remote. When the likelihood of a loss contingency becomes at least reasonably possible with respect to any of these disputes, or, as applicable in the future, if there is at least a reasonable possibility that a loss exceeding amounts already recognized may have been incurred, we will revise our disclosures in accordance with the relevant authoritative guidance.
	Additionally, we will accrue liability for loss contingencies when we believe that it is both probable that a liability has been incurred and that we can reasonably estimate the amount of the loss. We will review these accruals and adjust them to reflect ongoing negotiations, settlements, rulings, advice of legal counsel, and other relevant information. To the extent new information is obtained, and our views on the probable outcomes of claims, suits, assessments, investigations, or legal proceedings change, changes in our accrued liabilities would be recorded in the period in which such determination is made.

BASIS_OF_PRESENTATION_Policies

BASIS OF PRESENTATION (Policies)	9 Months Ended
	Sep. 30, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Segment Reporting	Segment Reporting – We disclose information about our operating segments based on the way that management organizes the segments within athenahealth for making operating decisions and assessing financial performance. Operating segments are identified as components of an enterprise about which separate discrete financial information is evaluated by the chief operating decision-maker (“CODM”), or decision-making group, in making decisions regarding resource allocation and assessing performance. We are in the process of analyzing the information that will be prepared and presented to the CODM due to the acquisitions of Epocrates, Inc. (“Epocrates”) and the Arsenal on the Charles during the nine months ended September 30, 2013 (see Note 2 Acquisitions). We anticipate that we will have at least two operating segments – athenahealth and Epocrates. Historically, we have operated in one segment.
Interim Tax Estimate	Interim Tax Estimate – Due to the fact that we are projecting a nominal pre-tax income (loss) for the year and have significant permanent differences, we cannot reasonably predict our estimated effective tax rate for the year; therefore, we have used a discrete tax approach in calculating the year-to-date provision for the period ended September 30, 2013.

ACQUISITIONS_Tables

ACQUISITIONS (Tables)	9 Months Ended
	Sep. 30, 2013
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Information	The following pro forma financial information summarizes the combined results of operations for athenahealth as though the acquisitions of Epocrates and the Arsenal on the Charles occurred on January 1, 2012. The unaudited pro forma financial information is as follows:
		Three months ended September 30,					Nine months ended September 30,
		2013			2012		2013			2012
	Revenue	$	151,527		$	132,833	$	443,196		$	390,673
	Net income (loss)	$	1,170		$	982	$	(14,953	)	$	(9,101	)
	Net income (loss) per share – Basic	$	0.03		$	0.03	$	(0.41	)	$	(0.25	)
	Net income (loss) per share – Diluted	$	0.03		$	0.03	$	(0.41	)	$	(0.24	)
Arsenal on the Charles
Business Acquisition [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The following table summarizes the estimated fair values of assets acquired and liabilities assumed as of the date of acquisition:
	Prepaid expenses and other current assets	$	685
	Property, equipment and buildings	144,071
	Purchased intangible assets	25,545
	Accrued expenses	(271		)
	Deferred revenue	(789		)
	Other long-term liabilities	(1,916		)
	Total identifiable net assets	$	167,325
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination	The following table sets forth the fair value of the preliminary components of the identifiable intangible assets acquired by asset class:
	Above market leases		$	3,298
	In-place leases		22,247
	Total intangible assets subject to amortization		$	25,545
Epocrates Inc
Business Acquisition [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	The following table summarizes the estimated fair values of assets acquired and liabilities assumed as of the date of acquisition:
	Accounts receivable	$	23,144
	Other current and long-term assets	3,833
	Property, equipment and capitalized software costs	4,168
	Purchased intangible assets	139,900
	Current liabilities	(11,054		)
	Deferred tax liabilities, net	(39,811		)
	Deferred revenue	(29,400		)
	Other long-term liabilities	(1,259		)
	Total identifiable net assets	$	89,521
	Goodwill	148,093
		$	237,614
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination	The following table sets forth the preliminary components of the identifiable intangible assets acquired by asset class and their preliminary estimated useful lives as of the date of acquisition:
		Fair Value			Useful Life
	Physician network	$	104,500		14 years
	Drug information content	10,000			5 years
	Trade name	11,500			10 years
	Customer backlog	2,900			1.5 years
	Epocrates non-compete agreement	4,500			1.5 years
	Developed technology	6,500			3 years
	Total intangible assets subject to amortization	$	139,900
Schedule of Business Acquisitions, by Acquisition	The acquisition date fair value of the consideration transferred for Epocrates, less cash and short-term investments acquired was approximately $237.6 million, which consisted of the following:
	Cash payments	$	294,632
	Fair value of vested stock options and restricted stock units assumed	13,028
	Fair value of total consideration	307,660
	Less cash acquired	(51,796		)
	Less short-term investments acquired	(18,250		)
	Total	$	237,614
Business Acquisition, Schedule of Integration Costs	The following table summarizes these amounts on the condensed consolidated statements of income for the nine months ended September 30, 2013:
	Summary of roll forward of integration costs
	Beginning balance, January 1, 2013	$	—
	Addition to provision	2,209
	Cash payments	(195		)
	Ending balance, March 31, 2013	$	2,014
	Addition to provision	979
	Change in estimate	(129		)
	Cash payments	(1,122		)
	Ending balance, June 30, 2013	$	1,742
	Addition to provision	526
	Change in estimate	(72		)
	Cash payments	(692		)
	Ending balance, September 30, 2013	$	1,504

NET_INCOME_LOSS_PER_SHARE_Tabl

NET INCOME (LOSS) PER SHARE (Tables)	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table reconciles the weighted average shares outstanding for basic and diluted net income (loss) per share for the periods indicated:
		Three Months Ended September 30,				Nine Months Ended September 30,
		2013		2012		2013			2012
	Net income (loss)	$	1,170	$	6,210	$	(10,551	)	$	12,792
	Weighted average shares used in computing basic net income (loss) per share	36,970		35,832		36,722			35,847
	Net income (loss) per share – Basic	$	0.03	$	0.17	$	(0.29	)	$	0.36
	Net income (loss)	$	1,170	$	6,210	$	(10,551	)	$	12,792
	Weighted average shares used in computing basic net income (loss) per share	36,970		35,832		36,722			35,847
	Effect of dilutive securities	1,373		1,380		—			1,191
	Weighted average shares used in computing diluted net income (loss) per share	38,343		37,212		36,722			37,038
	Net income (loss) per share – Diluted	$	0.03	$	0.17	$	(0.29	)	$	0.35

FAIR_VALUE_OF_FINANCIAL_INSTRU1

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following table presents information about our financial assets and liabilities that are measured at fair value on a recurring basis as of September 30, 2013, and December 31, 2012, and indicates the fair value hierarchy of the valuation techniques we utilized to determine such fair value. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities and fair values determined by Level 2 inputs utilize quoted prices (unadjusted) in active markets for similar assets or liabilities. The fair values determined by Level 3 inputs are unobservable values which are supported by little or no market activity.
		Fair Value Measurements At September 30, 2013, Using
		Level 1			Level 2			Level 3			Total
	Cash and cash equivalents:
	Money market funds	$	37		$	—		$	—		$	37
	Total assets	$	37		$	—		$	—		$	37
	Interest rate swap liability	$	—		$	(390	)	$	—		$	(390	)
	Total liabilities	$	—		$	(390	)	$	—		$	(390	)
		Fair Value Measurements as of December 31, 2012, Using
		Level 1			Level 2			Level 3			Total
	Cash and cash equivalents:
	Money market funds	$	89,480		$	—		$	—		$	89,480
	Available-for-sale investments:
	Commercial paper	—			11,748			—			11,748
	Corporate bonds	—			20,334			—			20,334
	Certificate of deposit	—			6,010			—			6,010
	Total assets	$	89,480		$	38,092		$	—		$	127,572
	Accrued contingent consideration	$	—		$	—		$	(448	)	$	(448	)
	Total liabilities	$	—		$	—		$	(448	)	$	(448	)
Reconciliations for Fair Values of Financial Instruments Determined by Level 3	The reconciliations for the fair values of financial instruments determined by Level 3 inputs for the periods presented are as follows:
		Three Months Ended September 30,						Nine Months Ended September 30,
		2013			2012			2013			2012
	Balance, beginning of period	$	448		$	6,259		$	448		$	8,176
	Payments	(524		)	(1,843		)	(524		)	(2,650		)
	Change in fair value (included in general and administrative expenses)	76			(3,675		)	76			(4,785		)
	Balance, end of period	$	—		$	741		$	—		$	741

PROPERTY_AND_EQUIPMENT_Tables

PROPERTY AND EQUIPMENT (Tables)	9 Months Ended
	Sep. 30, 2013
Property, Plant and Equipment [Abstract]
Property, and Equipment	Property and equipment consist of the following as of:
		September 30, 2013			December 31, 2012
	Equipment	$	74,358		$	56,078
	Furniture and fixtures	7,709			5,297
	Leasehold improvements	2,756			15,518
	Airplane	3,156			3,156
	Building	136,181			14,644
	Building improvements	18,281			3,500
	Land	23,059			2,035
	Land improvements	2,735			915
	Total property and equipment, at cost	268,235			101,143
	Accumulated depreciation and amortization	(68,156		)	(49,902		)
	Construction in progress	3,559			2,794
	Property and equipment, net	$	203,638		$	54,035

DEBT_Tables

DEBT (Tables)	9 Months Ended
	Sep. 30, 2013
Debt Disclosure [Abstract]
Schedule of Maturities of Long-term Debt	Future principle payments of the unsecured term loan facility at September 30, 2013 are as follows:
		Amount
	Remaining 2013	$	3,750
	2014	15,000
	2015	15,000
	2016	15,000
	2017	15,000
	Thereafter	128,750
	Total	192,500
	Less current portion	15,000
	Long-term portion	$	177,500
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The fair value of the interest rate swap recognized in other long-term liabilities and in OCI is as follows (in thousands):
							Fair Value
	Effective Date	Notional Amount		Fixed Rate		Maturity	30-Sep-13			31-Dec-12
	August 31, 2013	120,000		0.8396	%	August 31, 2016	$	(390	)	$	—

BASIS_OF_PRESENTATION_Addition

BASIS OF PRESENTATION (Additional Information) (Detail) (USD $)	3 Months Ended	9 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2013	Dec. 31, 2012
		Segment	Segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating segments		2	1
Total related party expense	$0.40
Total amount payable to related parties	$0.10	$0.10

ACQUISITIONS_Additional_Inform

ACQUISITIONS (Additional Information) (Details) (USD $)

0 Months Ended

5 Months Ended

9 Months Ended

33 Months Ended

0 Months Ended

2 Months Ended

5 Months Ended

7 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

33 Months Ended

10-May-13

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Mar. 12, 2013

Jun. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Arsenal on the Charles

Arsenal on the Charles

Arsenal on the Charles

Arsenal on the Charles

Arsenal on the Charles

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

acre

Direct operating expense

General and administrative

General and administrative

General and administrative

General and administrative

General and administrative

Business Acquisition [Line Items]

Number of acres

29

Total

$168,500,000

$237,614,000

Cash paid for property

167,300,000

294,632,000

Revenue

6,100,000

33,500,000

Net loss

-200,000

-17,600,000

Costs associated with third party tenant revenue

5,900,000

Transaction costs in connection with acquisition

2,400,000

3,100,000

0

2,700,000

3,200,000

Share conversion ratio

0.1239

Fair value of unvested options and restricted stock awards assumed

22,600,000

Fair value of vested stock options and restricted stock units assumed

13,028,000

Unrecognized stock-based compensation expense

9,600,000

Stock-based compensation expense

7,600,000

Stock-based compensation expense related to acceleration of stock awards upon termination

7,600,000

Severance and retention bonuses

$4,200,000

ACQUISITIONS_Summary_of_Recogn

ACQUISITIONS (Summary of Recognized Amounts of Identifiable Assets Acquired and Liabilities Assumed) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012	10-May-13	Mar. 12, 2013
In Thousands, unless otherwise specified			Arsenal on the Charles	Epocrates Inc
Business Acquisition [Line Items]
Prepaid expenses and other current assets			$685
Accounts receivable				23,144
Other current and long-term assets				3,833
Other current and long-term assets			144,071	4,168
Purchased intangible assets			25,545	139,900
Accrued expenses			-271	-11,054
Deferred tax liabilities, net				-39,811
Deferred revenue			-789	-29,400
Other long-term liabilities			-1,916	-1,259
Total identifiable net assets			167,325	89,521
Goodwill	196,183	48,090		148,093
Identifiable assets acquired and liabilities assumed, net				$237,614

ACQUISITIONS_Schedule_of_Ident

ACQUISITIONS (Schedule of Identifiable Intangible Assets Acquired) (Details) (USD $)

0 Months Ended

7 Months Ended

0 Months Ended

7 Months Ended

0 Months Ended

7 Months Ended

0 Months Ended

7 Months Ended

0 Months Ended

7 Months Ended

0 Months Ended

7 Months Ended

In Thousands, unless otherwise specified

10-May-13

10-May-13

10-May-13

Mar. 12, 2013

Mar. 12, 2013

Sep. 30, 2013

Mar. 12, 2013

Sep. 30, 2013

Mar. 12, 2013

Sep. 30, 2013

Mar. 12, 2013

Sep. 30, 2013

Mar. 12, 2013

Sep. 30, 2013

Mar. 12, 2013

Sep. 30, 2013

Arsenal on the Charles

Arsenal on the Charles

Arsenal on the Charles

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Epocrates Inc

Above market leases

In-place leases

Physician network

Physician network

Drug information content

Drug information content

Trade name

Trade name

Customer backlog

Customer backlog

Epocrates non-compete agreement

Epocrates non-compete agreement

Developed technology

Developed technology

Acquired Finite-Lived Intangible Assets [Line Items]

Purchased intangible assets - net

$25,545

$3,298

$22,247

$139,900

$104,500

$10,000

$11,500

$2,900

$4,500

$6,500

Weighted Average Remaining Useful Life (years)

14 years

5 years

10 years

1 year 6 months

1 year 6 months

3 years

ACQUISITIONS_Total_Considerati

ACQUISITIONS (Total Consideration on Acquisition Date) (Details) (Epocrates Inc, USD $)	0 Months Ended
In Thousands, unless otherwise specified	Mar. 12, 2013
Epocrates Inc
Business Acquisition [Line Items]
Cash payments	$294,632
Fair value of vested stock options and restricted stock units assumed	13,028
Fair value of total consideration	307,660
Less cash acquired	-51,796
Less short-term investments acquired	-18,250
Total	$237,614

ACQUISITIONS_Schedule_of_Integ

ACQUISITIONS (Schedule of Integration Costs) (Details) (Epocrates Inc, USD $)	3 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013
Epocrates Inc
Integration Costs [Roll Forward]
Beginning balance	$1,742	$2,014	$0
Addition to provision	526	979	2,209
Cash payments	-692	-1,122	-195
Change in estimate	-72	-129
Ending balance	$1,504	$1,742	$2,014

ACQUISITIONS_Schedule_of_Pro_F

ACQUISITIONS (Schedule of Pro Forma Information) (Details) (Epocrates and the Arsenal on the Charles, USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Epocrates and the Arsenal on the Charles
Business Acquisition [Line Items]
Revenue	$151,527	$132,833	$443,196	$390,673
Net income (loss)	$1,170	$982	($14,953)	($9,101)
Net income (loss) per share – Basic	$0.03	$0.03	($0.41)	($0.25)
Net income (loss) per share – Diluted	$0.03	$0.03	($0.41)	($0.24)

NET_INCOME_LOSS_PER_SHARE_Reco

NET INCOME (LOSS) PER SHARE (Reconciliation of Weighted Average Shares Outstanding for Basic and Diluted Net Income Per Share) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Net income (loss)	$1,170	$6,210	($10,551)	$12,792
Weighted average shares used in computing basic net income per share (shares)	36,970	35,832	36,722	35,847
Net income (loss) per share - basic (in dollars per share)	$0.03	$0.17	($0.29)	$0.36
Effect of dilutive securities (shares)	1,373	1,380	0	1,191
Weighted average shares used in computing diluted net income per share (shares)	38,343	37,212	36,722	37,038
Net income (loss) per share - diluted (in dollars per share)	$0.03	$0.17	($0.29)	$0.35

NET_INCOME_LOSS_PER_SHARE_Net_

NET INCOME (LOSS) PER SHARE (Net Income Per Share - Additional Information) (Detail)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Options and restricted stock units which have an antidilutive effect (shares)	0.3	0.4	3.5	0.4

FAIR_VALUE_OF_FINANCIAL_INSTRU2

FAIR VALUE OF FINANCIAL INSTRUMENTS (Fair Value of Financial Instruments - Additional Information) (Detail) (USD $)

9 Months Ended

1 Months Ended

3 Months Ended

3 Months Ended

9 Months Ended

Sep. 30, 2013

Sep. 30, 2012

Dec. 31, 2012

Dec. 31, 2011

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

10-May-13

Sep. 30, 2013

10-May-13

Level 2

Level 2

Proxsys LLC

Proxsys LLC

Proxsys LLC

Proxsys LLC

Proxsys LLC

Proxsys LLC

Proxsys LLC

Proxsys LLC

Proxsys LLC

Money market funds

Money market funds

Unsecured Debt

Unsecured Debt

Revolving Credit Facility

Revolving Credit Facility

Interest Rate Swap

Interest Rate Swap

Contingent Consideration

Second Potential Contingent Consideration

Second Potential Contingent Consideration

Second Potential Contingent Consideration

Second Potential Contingent Consideration

Second Potential Contingent Consideration

Second Potential Contingent Consideration

Final Potential Contingent Consideration

Final Potential Contingent Consideration

Senior Credit Facility

Senior Credit Facility

Senior Credit Facility

Senior Credit Facility

Fair Value, Measurements, Recurring

Fair Value, Measurements, Recurring

Level 3

Base Case Scenario

Base Case Scenario

Upside and Downside Senario

Upside and Downside Senario

General and administrative

General and administrative

Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]

Cash and cash equivalents

$62,274,000

$112,314,000

$154,988,000

$57,781,000

$100,000

$59,400,000

Amount outstanding for debt obligations

192,500,000

200,000,000

50,000,000

50,000,000

Amount outstanding for debt obligations

0

Long-term U.S. government backed securities

0

Fair value of swap recognized

400,000

0

Outstanding potential contingent consideration, lower range

0

0

Outstanding potential contigent consideration, higher range

5,000,000

5,000,000

Contingent consideration, payment date

Third quarter of 2013

Contingent consideration, assumptions, probability adjusted level

60.00%

60.00%

20.00%

20.00%

Accrued liability for the estimated fair value of contingent considerations

400,000

Contingent consideration, payment based on final selling results

76,000

-4,785,000

100,000

100,000

Contingent consideration, amount paid

$500,000

FAIR_VALUE_OF_FINANCIAL_INSTRU3

FAIR VALUE OF FINANCIAL INSTRUMENTS (Financial Assets and Liabilities that Are Measured at Fair Value on Recurring Basis) (Detail) (Fair Value, Measurements, Recurring, USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	$37	$127,572
Interest rate swap liability	-390
Total liabilities	-390	-448
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	37	89,480
Interest rate swap liability
Total liabilities
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets		38,092
Interest rate swap liability	-390
Total liabilities	-390
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets
Interest rate swap liability
Total liabilities		-448
Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accrued contingent consideration		-448
Contingent Consideration | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accrued contingent consideration
Contingent Consideration | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accrued contingent consideration
Contingent Consideration | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Accrued contingent consideration		-448
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	37	89,480
Money market funds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:	37	89,480
Money market funds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:
Money market funds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents:
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:		11,748
Commercial paper | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:
Commercial paper | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:		11,748
Commercial paper | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:		20,334
Corporate bonds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:
Corporate bonds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:		20,334
Corporate bonds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:
Certificate of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:		6,010
Certificate of deposit | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:
Certificate of deposit | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:		6,010
Certificate of deposit | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale investments:

FAIR_VALUE_OF_FINANCIAL_INSTRU4

FAIR VALUE OF FINANCIAL INSTRUMENTS (Reconciliations for Fair Values of Financial Instruments Determined by Level 3) (Detail) (Contingent Consideration, USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Contingent Consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance beginning of period	$448	$6,259	$448	$8,176
Payments	-524	-1,843	-524	-2,650
Change in fair value (included in general and administrative expenses)	76	-3,675	76	-4,785
Balance end of period	$0	$741	$0	$741

PROPERTY_AND_EQUIPMENT_Details

PROPERTY AND EQUIPMENT (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Total property and equipment, at cost	$268,235,000		$268,235,000		$101,143,000
Accumulated depreciation and amortization	-68,156,000		-68,156,000		-49,902,000
Construction in progress	3,559,000		3,559,000		2,794,000
Property and equipment - net	203,638,000		203,638,000		54,035,000
Depreciation expense	6,600,000	4,500,000	18,300,000	12,200,000
Equipment
Property, Plant and Equipment [Line Items]
Total property and equipment, at cost	74,358,000		74,358,000		56,078,000
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property and equipment, at cost	7,709,000		7,709,000		5,297,000
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment, at cost	2,756,000		2,756,000		15,518,000
Airplane
Property, Plant and Equipment [Line Items]
Total property and equipment, at cost	3,156,000		3,156,000		3,156,000
Building
Property, Plant and Equipment [Line Items]
Total property and equipment, at cost	136,181,000		136,181,000		14,644,000
Building improvements
Property, Plant and Equipment [Line Items]
Total property and equipment, at cost	18,281,000		18,281,000		3,500,000
Land
Property, Plant and Equipment [Line Items]
Total property and equipment, at cost	23,059,000		23,059,000		2,035,000
Land improvements
Property, Plant and Equipment [Line Items]
Total property and equipment, at cost	2,735,000		2,735,000		915,000
Arsenal on the Charles
Property, Plant and Equipment [Line Items]
Fair value of buildings acquired	121,300,000		121,300,000
Fair value of land acquired	21,000,000		21,000,000
Fair value of land improvements acquired	$1,800,000		$1,800,000

DEBT_Additional_Information_De

DEBT (Additional Information) (Detail) (USD $)

9 Months Ended

0 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

3 Months Ended

Sep. 30, 2013

Sep. 30, 2012

10-May-13

10-May-13

Sep. 30, 2013

10-May-13

Sep. 30, 2013

Sep. 30, 2013

Jan. 07, 2013

Oct. 20, 2011

Sep. 30, 2013

Mar. 10, 2013

Senior Credit Facility

Senior Credit Facility

Senior Credit Facility

Senior Credit Facility

Senior Credit Facility

Senior Credit Facility

Revolving Credit Agreement

Revolving Credit Agreement

Revolving Credit Agreement

Revolving Credit Agreement

Unsecured Debt

Unsecured Debt

Revolving Credit Facility

Revolving Credit Facility

Senior Notes

Debt Instrument [Line Items]

Revolving credit agreement

$100,000,000

Line of credit, term

5 years

Interest rate plus Federal Funds rate

0.50%

Interest rate plus one month LIBOR

1.00%

Amount of additional borrowing capacity for credit facility

100,000,000

55,000,000

Financing fees

1,300,000

0

Amount outstanding for debt obligations

200,000,000

192,500,000

50,000,000

50,000,000

155,000,000

Payments on line of credit

105,000,000

0

50,000,000

Credit Agreement, amount

325,000,000

200,000,000

125,000,000

Amount payable each quarter

3,750,000

Available on unsecured revolving credit facility

$75,000,000

Interest rate for Credit Facility

1.93%

DEBT_Schedule_of_Future_Paymen

DEBT (Schedule of Future Payments of Long Term Debt) (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Line of Credit Facility [Line Items]
Current portion of long-term debt	$15,000	$0
Long-term debt, net of current portion	177,500	0
Senior Credit Facility | Unsecured Debt
Line of Credit Facility [Line Items]
Remaining 2013	3,750
2014	15,000
2015	15,000
2016	15,000
2017	15,000
Thereafter	128,750
Total	192,500
Current portion of long-term debt	15,000
Long-term debt, net of current portion	$177,500

DEBT_Interest_Rate_Swap_Agreem

DEBT (Interest Rate Swap Agreement) (Details) (Interest Rate Swap, Designated as Hedging Instrument, USD $)	Sep. 30, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Notional Amount	$120,000,000
Fixed Rate	0.84%
Other Long Term Liabilities
Derivatives, Fair Value [Line Items]
Fair value of swap recognized	($390,000)	$0

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Additional Information) (Detail) (Bushansky v Epocrates Inc, et al, USD $)	0 Months Ended
In Thousands, unless otherwise specified	Oct. 04, 2013
Bushansky v Epocrates Inc, et al
Loss Contingencies [Line Items]
Amount of final settlement approval	$335