Revenue Recognition - Total Gross Product (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Provision for product sales allowances and accruals:
Revenues	$ 122,238	$ 124,331	$ 385,881	$ 367,243
Product Revenue
Disaggregation of Revenue [Line Items]
Gross product sales	238,856	235,299	776,458	676,377
Provision for product sales allowances and accruals:
Contractual adjustments	93,213	80,110	290,896	225,622
Governmental rebates	23,405	30,858	99,756	83,565
Total	116,618	110,968	390,652	309,187
Revenues	$ 122,238	$ 124,331	$ 385,806	$ 367,190

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Revenue Adjustment, Governmental Rebates

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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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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
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