Subsequent Event	9 Months Ended
Sep. 30, 2018
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventOn October 1, 2018, we completed the purchase of a trucking company for $10.0 million that owned approximately 113 tractor trailer trucks and 125 trailers operating in the Red River area in North Texas and South Central Oklahoma. This acquisition will be included in our crude oil marketing segment.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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