Commitments and Contingencies	9 Months Ended
Sep. 30, 2012
Commitments and Contingencies [Abstract]
Commitments and Contingencies	10. Commitments and Contingencies Commitments In January 2012, we entered into a contract with our drug supply manufacturer for drug required for our dog toxicology study at a total cost of $1.4 million. Additionally, in the quarter ended June 30, 2012, we entered into contracts totaling $3.0 million for the manufacturing of clinical drug supplies. Legal Proceedings Cacchillo v. Insmed On October 6, 2010, a complaint was filed against us by Angeline Cacchillo ("Plaintiff") in the U.S. District Court for the Northern District of New York (the "Court"), captioned Cacchillo v. Insmed, Inc., No. 1:10-cv-0199, seeking monetary damages and a court order requiring Insmed to support Plaintiff's compassionate use application to the FDA and if approved, to provide Plaintiff with IPLEX. Plaintiff was a participant in the phase II clinical trial of IPLEX sponsored by us evaluating the effectiveness of the investigational drug in patients with type 1 myotonic muscular dystrophy ("MMD"). In the complaint, Plaintiff alleged (i) violation of constitutional due process and equal protection by depriving Plaintiff of continued access to IPLEX, (ii) fraudulent inducement to enter the phase II clinical trial with the false promise to support Plaintiff's compassionate use application to the FDA, (iii) negligent representation that we would support Plaintiff's compassionate use application, (iv) breach of contract, seeking monetary and non-monetary damages, (v) intentional infliction of emotional distress by refusing to support Plaintiff's compassionate use application after providing IPLEX, (vi) violation of an assumed duty of care to Plaintiff, (vii) breach of fiduciary duty to Plaintiff, (viii) negligence and (ix) unjust enrichment. Plaintiff seeks compensatory and punitive monetary damages and sought injunction relief as noted above. On October 7, 2010, Plaintiff filed a motion for a preliminary injunction that would require us to provide a written statement supporting the "compassionate use" of IPLEX for Plaintiff and directing us to provide IPLEX to Plaintiff at cost in the event that the compassionate use application were granted by the FDA. On October 22, 2010, the Court denied Plaintiff's motion for the preliminary injunction concluding that the Court lacked subject matter jurisdiction with respect to her claim for a preliminary injunction. Plaintiff appealed the Court's denial of her motion for a preliminary injunction to the U.S. Court of Appeals for the Second Circuit, which affirmed the trial court's order denying the Plaintiff's motion for a preliminary injunction. We filed a motion with the Court to dismiss all of the outstanding claims, and on June 29, 2011, the Court dismissed six of Plaintiff's claims, leaving outstanding the claims for (i) fraudulent inducement, (ii) negligent misrepresentation, and (iii) breach of contract. We filed an answer and affirmative defenses with the Court on July 12, 2011. Plaintiff's claim for monetary damages with respect to these claims remains outstanding. The parties completed discovery on or about June 1, 2012. We filed a Motion for Summary Judgment on August 1, 2012 seeking judgment in our favor on the three claims remaining in the case and the motion was fully submitted on October 9, 2012. We expect a decision from the Court sometime later this year. If the Court denies our motion with respect to any of Plaintiff's claims, trial is currently scheduled to begin in January 2013. We believe that the allegations contained in the complaint are without merit and we intend to continue to vigorously defend this action. It is not possible at this time to estimate the amount of loss or range of possible loss, if any, that might result from an adverse resolution of this action. Pilkiewicz v. Transave LLC On March 28, 2011, Frank G. Pilkiewicz and other former stockholders of Transave (collectively, the "Petitioners") filed an appraisal action against our subsidiary Transave, LLC in the Delaware Court of Chancery captioned Frank G. Pilkiewicz, et al. v. Transave, LLC , C.A. No. 6319-CS. On December 13, 2011, following the mailing of the revised notice of appraisal rights in accordance with the settlement terms of Mackinson et al. v. Insmed , an Amended Petition for Appraisal of Stock was filed by the Petitioners. The Petitioners seek appraisal under Delaware law of their total combined common stock holdings representing total dissenting shares of approximately 7.77 million shares of Transave, Inc. common stock (the "Transave Stock"). The Petitioners are challenging the value of the consideration that they would be entitled to receive for their Transave Stock under the terms of the merger. Under the terms of the merger agreement, certain of the former stockholders of Transave (the "Transave Stockholders") are obligated to indemnify us for certain liabilities in connection with the appraisal action. We notified the Transave Stockholders in May 2012 that we are seeking indemnification in accordance with the merger agreement and that we will continue to retain the aggregate amount of the holdback shares totaling 1.76 million shares, as security for any indemnification payments due under the merger agreement. Discovery is ongoing and we anticipate that trial will be scheduled in the second half of 2013. We believe that the allegations contained in the amended petition are without merit and we intend to continue to vigorously defend this action. It is not possible at this time to estimate the amount of loss or range of possible loss, if any, that might result from an adverse resolution of this action. From time to time, we are a party to various other lawsuits, claims and other legal proceedings that arise in the ordinary course of our business. While the outcomes of these matters are uncertain, management does not expect that the ultimate costs to resolve these matters will have a material adverse effect on our consolidated financial position, results of operations or cash flows.

10. Commitments and Contingencies

Commitments

In January 2012, we entered into a contract with our drug supply manufacturer for drug required for our dog toxicology study at a total cost of $1.4 million. Additionally, in the quarter ended June 30, 2012, we entered into contracts totaling $3.0 million for the manufacturing of clinical drug supplies.

Legal Proceedings

Cacchillo v. Insmed

On October 6, 2010, a complaint was filed against us by Angeline Cacchillo ("Plaintiff") in the U.S. District Court for the Northern District of New York (the "Court"), captioned Cacchillo v. Insmed, Inc., No. 1:10-cv-0199, seeking monetary damages and a court order requiring Insmed to support Plaintiff's compassionate use application to the FDA and if approved, to provide Plaintiff with IPLEX. Plaintiff was a participant in the phase II clinical trial of IPLEX sponsored by us evaluating the effectiveness of the investigational drug in patients with type 1 myotonic muscular dystrophy ("MMD"). In the complaint, Plaintiff alleged (i) violation of constitutional due process and equal protection by depriving Plaintiff of continued access to IPLEX, (ii) fraudulent inducement to enter the phase II clinical trial with the false promise to support Plaintiff's compassionate use application to the FDA, (iii) negligent representation that we would support Plaintiff's compassionate use application, (iv) breach of contract, seeking monetary and non-monetary damages, (v) intentional infliction of emotional distress by refusing to support Plaintiff's compassionate use application after providing IPLEX, (vi) violation of an assumed duty of care to Plaintiff, (vii) breach of fiduciary duty to Plaintiff, (viii) negligence and (ix) unjust enrichment. Plaintiff seeks compensatory and punitive monetary damages and sought injunction relief as noted above.

On October 7, 2010, Plaintiff filed a motion for a preliminary injunction that would require us to provide a written statement supporting the "compassionate use" of IPLEX for Plaintiff and directing us to provide IPLEX to Plaintiff at cost in the event that the compassionate use application were granted by the FDA. On October 22, 2010, the Court denied Plaintiff's motion for the preliminary injunction concluding that the Court lacked subject matter jurisdiction with respect to her claim for a preliminary injunction. Plaintiff appealed the Court's denial of her motion for a preliminary injunction to the U.S. Court of Appeals for the Second Circuit, which affirmed the trial court's order denying the Plaintiff's motion for a preliminary injunction.

We filed a motion with the Court to dismiss all of the outstanding claims, and on June 29, 2011, the Court dismissed six of Plaintiff's claims, leaving outstanding the claims for (i) fraudulent inducement, (ii) negligent misrepresentation, and (iii) breach of contract. We filed an answer and affirmative defenses with the Court on July 12, 2011. Plaintiff's claim for monetary damages with respect to these claims remains outstanding. The parties completed discovery on or about June 1, 2012. We filed a Motion for Summary Judgment on August 1, 2012 seeking judgment in our favor on the three claims remaining in the case and the motion was fully submitted on October 9, 2012. We expect a decision from the Court sometime later this year. If the Court denies our motion with respect to any of Plaintiff's claims, trial is currently scheduled to begin in January 2013.

We believe that the allegations contained in the complaint are without merit and we intend to continue to vigorously defend this action. It is not possible at this time to estimate the amount of loss or range of possible loss, if any, that might result from an adverse resolution of this action.

Pilkiewicz v. Transave LLC

On March 28, 2011, Frank G. Pilkiewicz and other former stockholders of Transave (collectively, the "Petitioners") filed an appraisal action against our subsidiary Transave, LLC in the Delaware Court of Chancery captioned Frank G. Pilkiewicz, et al. v. Transave, LLC , C.A. No. 6319-CS. On December 13, 2011, following the mailing of the revised notice of appraisal rights in accordance with the settlement terms of Mackinson et al. v. Insmed , an Amended Petition for Appraisal of Stock was filed by the Petitioners.

The Petitioners seek appraisal under Delaware law of their total combined common stock holdings representing total dissenting shares of approximately 7.77 million shares of Transave, Inc. common stock (the "Transave Stock"). The Petitioners are challenging the value of the consideration that they would be entitled to receive for their Transave Stock under the terms of the merger.

Under the terms of the merger agreement, certain of the former stockholders of Transave (the "Transave Stockholders") are obligated to indemnify us for certain liabilities in connection with the appraisal action. We notified the Transave Stockholders in May 2012 that we are seeking indemnification in accordance with the merger agreement and that we will continue to retain the aggregate amount of the holdback shares totaling 1.76 million shares, as security for any indemnification payments due under the merger agreement. Discovery is ongoing and we anticipate that trial will be scheduled in the second half of 2013. We believe that the allegations contained in the amended petition are without merit and we intend to continue to vigorously defend this action. It is not possible at this time to estimate the amount of loss or range of possible loss, if any, that might result from an adverse resolution of this action.

From time to time, we are a party to various other lawsuits, claims and other legal proceedings that arise in the ordinary course of our business. While the outcomes of these matters are uncertain, management does not expect that the ultimate costs to resolve these matters will have a material adverse effect on our consolidated financial position, results of operations or cash flows.