Subsequent Events	12 Months Ended
Dec. 31, 2012
Subsequent Events [Abstract]
Subsequent Events	Subsequent Event On January 7, 2013, the Company entered into a definitive agreement with athenahealth, Inc. ("athenahealth"), a leading provider of cloud-based electronic health record, or EHR, practice management and care coordination services to medical groups and health systems, pursuant to which, upon the terms and subject to the conditions set forth therein, the Company would merge with and into a wholly-owned subsidiary of athenahealth and continue on as a surviving entity and wholly-owned subsidiary of athenahealth. The completion of the proposed acquisition is subject to the satisfaction of various closing conditions, including the approval of the merger by our stockholders. The merger is expected to be completed in the first quarter of 2013 at a price of $11.75 per common share to stockholders of record as of February 7, 2013, for an aggregate purchase price of approximately $293 million. The purchase price represents a 22% premium over the closing price per share of Epocrates' stock on January 4, 2013. We paid legal fees associated with this transaction of $0.2 million during the year ended December 31, 2012. We were not obligated to pay any material banker fees incurred in connection with the transaction until and unless an agreement was reached. As the agreement was not signed until 2013, the fees associated with the transaction are not reflected in our consolidated financial statements for the year ended December 31, 2012. In connection with the merger agreement, the Company incurred deal costs from our bankers and external legal counsel. Banker fees to be paid during 2013 include approximately $0.8 million for the acquisition fairness opinion and 1% of the transaction value. External legal counsel fees associated with this transaction are expected to amount to approximately $0.7 million. The Company has also entered into agreements to provide retention bonuses to certain key employees in order to facilitate the completion of this transaction and anticipated integration with athenahealth. Such bonuses are expected to amount to $1.5 million, and will be paid by Epocrates only if the merger is not consummated. If the deal is completed, these bonuses will be paid by athenahealth.

Subsequent Event

On January 7, 2013, the Company entered into a definitive agreement with athenahealth, Inc. ("athenahealth"), a leading provider of cloud-based electronic health record, or EHR, practice management and care coordination services to medical groups and health systems, pursuant to which, upon the terms and subject to the conditions set forth therein, the Company would merge with and into a wholly-owned subsidiary of athenahealth and continue on as a surviving entity and wholly-owned subsidiary of athenahealth. The completion of the proposed acquisition is subject to the satisfaction of various closing conditions, including the approval of the merger by our stockholders. The merger is expected to be completed in the first quarter of 2013 at a price of $11.75 per common share to stockholders of record as of February 7, 2013, for an aggregate purchase price of approximately $293 million. The purchase price represents a 22% premium over the closing price per share of Epocrates' stock on January 4, 2013. We paid legal fees associated with this transaction of $0.2 million during the year ended December 31, 2012. We were not obligated to pay any material banker fees incurred in connection with the transaction until and unless an agreement was reached. As the agreement was not signed until 2013, the fees associated with the transaction are not reflected in our consolidated financial statements for the year ended December 31, 2012.

In connection with the merger agreement, the Company incurred deal costs from our bankers and external legal counsel. Banker fees to be paid during 2013 include approximately $0.8 million for the acquisition fairness opinion and 1% of the transaction value. External legal counsel fees associated with this transaction are expected to amount to approximately $0.7 million. The Company has also entered into agreements to provide retention bonuses to certain key employees in order to facilitate the completion of this transaction and anticipated integration with athenahealth. Such bonuses are expected to amount to $1.5 million, and will be paid by Epocrates only if the merger is not consummated. If the deal is completed, these bonuses will be paid by athenahealth.