Collaborative and Other Relationships (Details 1)	12 Months Ended
	Dec. 31, 2014
Sobi rate to Biogen on net sales in the Sobi Territory [Member]
Mechanism for reimbursement, under the amended agreement amounts payable
Reimbursement, under the amended agreement, Method	Royalty
Rate during the reimbursement period	Base Rate plus 5%	[1]
Sobi rate to Biogen on net sales in the Sobi Territory [Member] | Maximum
Mechanism for reimbursement, under the amended agreement amounts payable
Base rate following first commercial sale in the territory	12.00%	[1]
Sobi rate to Biogen on net sales in the Sobi Territory [Member] | Minimum
Mechanism for reimbursement, under the amended agreement amounts payable
Base rate following first commercial sale in the territory	10.00%	[1]
Biogen rate to sobi on net sales in the Biogen North America Territory [Member]
Mechanism for reimbursement, under the amended agreement amounts payable
Reimbursement, under the amended agreement, Method	Royalty
Rate during the reimbursement period	Base Rate less 5%	[1]
Biogen rate to sobi on net sales in the Biogen North America Territory [Member] | Maximum
Mechanism for reimbursement, under the amended agreement amounts payable
Base rate following first commercial sale in the territory	12.00%	[1]
Biogen rate to sobi on net sales in the Biogen North America Territory [Member] | Minimum
Mechanism for reimbursement, under the amended agreement amounts payable
Base rate following first commercial sale in the territory	10.00%	[1]
Biogen rate to sobi on net sales in the Biogen North America Territory [Member] | Sobi Territory [Member]
Mechanism for reimbursement, under the amended agreement amounts payable
Rate prior to first commercial sale in the territory	2.00%
Biogen rate to sobi on net sales in the Biogen direct Territory [Member]
Mechanism for reimbursement, under the amended agreement amounts payable
Reimbursement, under the amended agreement, Method	Royalty
Rate during the reimbursement period	Base Rate less 5%	[1]
Biogen rate to sobi on net sales in the Biogen direct Territory [Member] | Maximum
Mechanism for reimbursement, under the amended agreement amounts payable
Base rate following first commercial sale in the territory	17.00%	[1]
Biogen rate to sobi on net sales in the Biogen direct Territory [Member] | Minimum
Mechanism for reimbursement, under the amended agreement amounts payable
Base rate following first commercial sale in the territory	15.00%	[1]
Biogen rate to sobi on net sales in the Biogen direct Territory [Member] | Sobi Territory [Member]
Mechanism for reimbursement, under the amended agreement amounts payable
Rate prior to first commercial sale in the territory	2.00%
Biogen rate to Sobi on net revenue from the Biogen distributor Territory [Member]
Mechanism for reimbursement, under the amended agreement amounts payable
Reimbursement, under the amended agreement, Method	Net Revenue Share	[2],[3]
Rate during the reimbursement period	Base Rate less 15%	[1],[2],[3]
Biogen rate to Sobi on net revenue from the Biogen distributor Territory [Member] | Sobi Territory [Member]
Mechanism for reimbursement, under the amended agreement amounts payable
Rate prior to first commercial sale in the territory	10.00%	[2],[3]
Base rate following first commercial sale in the territory	50.00%	[1],[2],[3]

[1] A credit will be issued to Sobi against its reimbursement of the Opt-in Consideration in an amount equal to the difference in the rate paid by Biogen Idec to Sobi on sales in the Biogen Idec territories for certain periods prior to the first commercial sale in the Sobi Territory versus the rate that otherwise would have been payable on such sales.

[2] The Biogen Idec Distributor Territory represents Biogen Idec territories where sales are derived utilizing a third-party distributor.

[3] Net revenue represents Biogen Idec’s pre-tax receipts from third-party distributors, less expenses incurred by Biogen Idec in the conduct of commercialization activities supporting the distributor activities.