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		9 Months Ended
Net Product Sales (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Revenue Disclosure [Line Items]
Net product sales	$ 957,367	$ 857,468	$ 2,739,745	$ 2,475,869
Activity of Sales Related Deductions [Roll Forward]
Balance	75,301	37,753	75,301	37,753	$ 45,851	$ 55,249
Provision related to current period sales			295,977	200,077
Credits/payments			(266,527)	(217,573)
Rebates and Chargebacks
Activity of Sales Related Deductions [Roll Forward]
Balance	25,500	7,426	25,500	7,426	12,712	6,419
Provision related to current period sales			121,599	63,510
Credits/payments			(108,811)	(62,503)
Distribution Related Fees
Activity of Sales Related Deductions [Roll Forward]
Balance	34,053	26,585	34,053	26,585	29,465	48,313
Provision related to current period sales			140,860	113,755
Credits/payments			(136,272)	(135,483)
Other Sales Related Deductions
Activity of Sales Related Deductions [Roll Forward]
Balance	$ 15,748	$ 3,742	15,748	3,742	$ 3,674	$ 517
Provision related to current period sales			33,518	22,812
Credits/payments			$ (21,444)	$ (19,587)
Besse Medical [Member] \| Customer concentration risk \| Gross Sales Revenue
Risks and Uncertainties [Abstract]
Concentration risk, percentage	51.00%	54.00%	51.00%	56.00%
EYLEA
Revenue Disclosure [Line Items]
Net product sales	$ 953,279	$ 853,588	$ 2,727,132	$ 2,465,369
ARCALYST
Revenue Disclosure [Line Items]
Net product sales	$ 4,088	$ 3,880	$ 12,613	$ 10,500
McKesson Corporation [Member] \| Customer concentration risk \| Gross Sales Revenue
Risks and Uncertainties [Abstract]
Concentration risk, percentage	29.00%	28.00%	29.00%	28.00%
Curascript SD [Member] \| Customer concentration risk \| Gross Sales Revenue
Risks and Uncertainties [Abstract]
Concentration risk, percentage	19.00%	17.00%	19.00%	15.00%
Minimum [Member] \| Customer concentration risk \| Gross Sales Revenue
Risks and Uncertainties [Abstract]
Concentration risk, percentage	10.00%	10.00%	10.00%	10.00%