Equity (Details Textual) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2019	Feb. 25, 2019
EQUITY (Textual) [Abstract]
Outstanding unvested equity compensation awards	1,639,668
Additional equity compensation awards that could vest if certain targets are achieved	542,000
Unvested Dividend Equivalent Value	$ 1.9
Equity compensation awards granted during the period	681,948
Weighted average grant date fair value of equity awards granted during the period	$ 15.22
Employee Stock [Member]
EQUITY (Textual) [Abstract]
Employee Stock Purchase Plan shares issued during period	32,468
Stock Compensation Plan [Member]
EQUITY (Textual) [Abstract]
Vested common stock	298,142
SemCAMS Midstream [Member]
EQUITY (Textual) [Abstract]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	49.00%	49.00%
Maurepas Pipeline LLC [Member]
EQUITY (Textual) [Abstract]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	49.00%

Equity.

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Potentialy Vested

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- Definition

Unvested Dividend Equivalent Value

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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