Segment Information (Additional Information) (Details)	9 Months Ended
Sep. 30, 2018 customer segment
Concentration Risk [Line Items]
Number of reportable segments \| segment	1
Accounts Receivable [Member]
Concentration Risk [Line Items]
Number of customers \| customer	0

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

No definition available.

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration