Related-Party Transactions (Details) - Commercial Agreements [Member] - bbl bbl in Thousands		6 Months Ended
Mar. 31, 2017	Jun. 30, 2018
Related Party Transaction [Line Items]
Volume of storage tank (barrels)	180
Agreement expiration date, initial term		Jun. 30, 2033

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