Earnings Per Common Share (Narrative) (Details)	6 Months Ended
Jun. 30, 2019 $ / bbl
Derivative [Line Items]
Period of trailing average of WTI	30 days
Minimum [Member] \| West Texas Intermediate [Member]
Derivative [Line Items]
Compensation reimbursement	85

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.

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Period Type:	duration