Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_PropertyPlantAndEquipmentGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Acquisitions - Van Hook Crude Acquisition Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Mar. 15, 2018
Business Acquisition [Line Items]
Total assets acquired	$ 305,862	$ 291,205	$ 15,549
Machinery, equipment and tooling
Business Acquisition [Line Items]
Total assets acquired	16,080	14,858	1,478
Plant and buildings
Business Acquisition [Line Items]
Total assets acquired	160,413	158,882	1,407
Railroad and sidings
Business Acquisition [Line Items]
Total assets acquired	$ 27,347	$ 27,347	9,926
Land improvements
Business Acquisition [Line Items]
Total assets acquired			$ 2,738