Commitments and Contingencies - Legal Matters (Details) - ARC Medical Design $ in Thousands	1 Months Ended	3 Months Ended
May 31, 2017 patent	Apr. 30, 2018 USD ($)
Loss Contingencies [Line Items]
Number of patents allegedly infringed (in patents) \| patent	2
Legal settlement costs \| $		$ 2,608

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.

No definition available.

Name:	us-gaap_LossContingenciesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration