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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Intangible assets (Detail Textuals) (Cequent Pharmaceuticals, Inc., USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jul. 31, 2010
Business Acquisition [Line Items]
Intangible assets	$ 57.1	$ 46.9		$ 22.7
Fair value discount rate	22.00%	22.00%
Loss on impairment of intangible assets			16.0
FAP
Business Acquisition [Line Items]
Intangible assets	49.2	40.3		19.3
tkRNAi
Business Acquisition [Line Items]
Intangible assets	$ 7.9	$ 6.6		$ 3.4