For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

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Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to accounts other than costs and expenses.

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Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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Net Product Sales (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Net Product Sales (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Revenue Disclosure [Line Items]
Net product sales	$ 924,133	$ 834,219	$ 1,782,378	$ 1,618,401
Activity of Sales Related Deductions [Roll Forward]
Balance	55,028	40,846	55,028	40,846	$ 45,851	$ 55,249
Provision related to current period sales			188,858	127,956
Credits/payments			(179,681)	(142,359)
Rebates and Chargebacks
Activity of Sales Related Deductions [Roll Forward]
Balance	23,112	11,635	23,112	11,635	12,712	6,419
Provision related to current period sales			78,250	41,326
Credits/payments			(67,850)	(36,110)
Distribution Related Fees
Activity of Sales Related Deductions [Roll Forward]
Balance	29,023	28,135	29,023	28,135	29,465	48,313
Provision related to current period sales			90,077	74,289
Credits/payments			(90,519)	(94,467)
Other Sales Related Deductions
Activity of Sales Related Deductions [Roll Forward]
Balance	$ 2,893	$ 1,076	2,893	1,076	$ 3,674	$ 517
Provision related to current period sales			20,531	12,341
Credits/payments			$ (21,312)	$ (11,782)
Besse Medical [Member] \| Customer concentration risk \| Gross Sales Revenue
Risks and Uncertainties [Abstract]
Concentration risk, percentage	50.00%	56.00%	51.00%	58.00%
EYLEA
Revenue Disclosure [Line Items]
Net product sales	$ 919,466	$ 830,936	$ 1,773,853	$ 1,611,781
ARCALYST
Revenue Disclosure [Line Items]
Net product sales	$ 4,667	$ 3,283	$ 8,525	$ 6,620
McKesson Corporation [Member] \| Customer concentration risk \| Gross Sales Revenue
Risks and Uncertainties [Abstract]
Concentration risk, percentage	29.00%	28.00%	28.00%	28.00%
Curascript SD [Member] \| Customer concentration risk \| Gross Sales Revenue
Risks and Uncertainties [Abstract]
Concentration risk, percentage	20.00%	15.00%	20.00%	13.00%
Minimum [Member] \| Customer concentration risk \| Gross Sales Revenue
Risks and Uncertainties [Abstract]
Concentration risk, percentage	10.00%	10.00%	10.00%	10.00%