Cash, Cash Equivalents and Restricted Cash	12 Months Ended
Dec. 31, 2014
Cash, Cash Equivalents and Available for Sale Securities [Abstract]
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments purchased with original maturities at the date of purchase of three months or less to be cash equivalents. Cash and cash equivalents included cash of $364.7 million and $330.8 million at December 31, 2014 and December 31, 2013, respectively. Cash and cash equivalents at December 31, 2014 and December 31, 2013 included investments of $6.0 million and $45.9 million, respectively, in money market funds and commercial paper with original maturities of less than three months. These investments are carried at cost, which approximates fair value. The Company measures all original maturities from the date the investment was originally purchased by the Company. At December 31, 2014 and December 31, 2013 the Company did not hold any available for sale securities. Restricted Cash The Company had restricted cash of $1.4 million and $1.6 million at December 31, 2014 and at December 31, 2013, which is included in restricted cash on the consolidated balance sheets. Restricted cash of $1.0 million at December 31, 2014 and December 31, 2013 collateralizes outstanding letters of credit associated with the lease of its corporate office space in Parsippany, New Jersey. The funds are invested in certificates of deposit. The letter of credit permits draws by the landlord to cure defaults by the Company. In addition, as a result of the acquisition of Targanta Therapeutics Corporation (Targanta) in 2009, the Company had at December 31, 2014 and December 31, 2013 restricted cash of $0.1 million and $0.3 million, respectively, in the form of a guaranteed investment certificate collateralizing an available credit facility. The Company also had at December 31, 2014 and December 31, 2013 restricted cash of $0.3 million, respectively, related to certain foreign tender requirements.

Cash, Cash Equivalents and Restricted Cash

The Company considers all highly liquid investments purchased with original maturities at the date of purchase of three months or less to be cash equivalents. Cash and cash equivalents included cash of $364.7 million and $330.8 million at December 31, 2014 and December 31, 2013, respectively. Cash and cash equivalents at December 31, 2014 and December 31, 2013 included investments of $6.0 million and $45.9 million, respectively, in money market funds and commercial paper with original maturities of less than three months. These investments are carried at cost, which approximates fair value. The Company measures all original maturities from the date the investment was originally purchased by the Company.

At December 31, 2014 and December 31, 2013 the Company did not hold any available for sale securities.

Restricted Cash

The Company had restricted cash of $1.4 million and $1.6 million at December 31, 2014 and at December 31, 2013, which is included in restricted cash on the consolidated balance sheets. Restricted cash of $1.0 million at December 31, 2014 and December 31, 2013 collateralizes outstanding letters of credit associated with the lease of its corporate office space in Parsippany, New Jersey. The funds are invested in certificates of deposit. The letter of credit permits draws by the landlord to cure defaults by the Company. In addition, as a result of the acquisition of Targanta Therapeutics Corporation (Targanta) in 2009, the Company had at December 31, 2014 and December 31, 2013 restricted cash of $0.1 million and $0.3 million, respectively, in the form of a guaranteed investment certificate collateralizing an available credit facility. The Company also had at December 31, 2014 and December 31, 2013 restricted cash of $0.3 million, respectively, related to certain foreign tender requirements.