Product Revenue, Net (Schedule of Product Revenue, Net) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Product revenue, net	$ 61,950	$ 46,986	$ 180,502	$ 126,524
Product [Member]
Disaggregation of Revenue [Line Items]
Product revenue, net	61,545	46,581	179,286	124,908
Product [Member] \| United States [Member]
Disaggregation of Revenue [Line Items]
Product revenue, net	45,232	36,684	133,914	99,697
Product [Member] \| Non-US [Member]
Disaggregation of Revenue [Line Items]
Product revenue, net	$ 16,313	$ 9,897	$ 45,372	$ 25,211

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Name:	us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration