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Represents the period over which the estimated undiscounted royalty amounts could be paid under the Access License Agreement.

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Represents the other adjustments involving fair value of financial instrument classified as a liability.

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No definition available.

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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Face (par) amount of debt instrument at time of issuance.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair Value Measurements - Contingent Consideration (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Feb. 14, 2014
Reconciliation of contingent consideration obligations related to acquisitions
Balance at beginning of period	$ 218,702
Payments made	(322)
Adjustments to fair value of contingent consideration	4,525	$ (2,535)
Other adjustments	40
Balance at end of period	$ 222,945
Interest rate (as a percent)	2.50%		2.50%
Estimated fair value of long-term debt	$ 322,100
2023 Senior Notes
Reconciliation of contingent consideration obligations related to acquisitions
Estimated fair value of long-term debt	$ 477,500
Convertible Debt
Reconciliation of contingent consideration obligations related to acquisitions
Aggregate principal amount of debt issued				$ 200,000
Interest rate (as a percent)	2.50%
Estimated fair value of long-term debt	$ 322,100
Abeona Therapeutics, Inc \| Licensing Agreements
Reconciliation of contingent consideration obligations related to acquisitions
Period over which estimated undiscounted royalty amounts could be paid	10 years
Abeona Therapeutics, Inc \| Licensing Agreements \| Fair Value, Inputs, Level 3
Reconciliation of contingent consideration obligations related to acquisitions
Discount rate (as a percent)	12.00%
Abeona Therapeutics, Inc \| Licensing Agreements \| Minimum
Reconciliation of contingent consideration obligations related to acquisitions
Estimated undiscounted royalty amounts payable	$ 10,000
Abeona Therapeutics, Inc \| Licensing Agreements \| Maximum
Reconciliation of contingent consideration obligations related to acquisitions
Estimated undiscounted royalty amounts payable	$ 18,000
Lumara Health
Reconciliation of contingent consideration obligations related to acquisitions
Discount rate (as a percent)	5.00%
Makena \| Licensing Agreements
Reconciliation of contingent consideration obligations related to acquisitions
Adjustments to fair value of contingent consideration	$ 7,700
Makena \| Abeona Therapeutics, Inc \| Licensing Agreements
Reconciliation of contingent consideration obligations related to acquisitions
Contingent consideration classified as short term liability	96,100
MuGard \| Abeona Therapeutics, Inc \| Licensing Agreements
Reconciliation of contingent consideration obligations related to acquisitions
Adjustments to fair value of contingent consideration	(3,200)
MuGard \| Lumara Health \| Licensing Agreements
Reconciliation of contingent consideration obligations related to acquisitions
Contingent consideration classified as short term liability	$ 700