Equity (Details Textual) $ / shares in Units, $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($) $ / shares shares
EQUITY (Textual) [Abstract]
Outstanding unvested equity compensation awards	1,638,887
Additional equity compensation awards that could vest if certain targets are achieved	538,000
Unvested Dividend Equivalent Value \| $	$ 2.1
Equity compensation awards granted during the period	818,603
Weighted average grant date fair value of equity awards granted during the period \| $ / shares	$ 14.80
Employee Stock [Member]
EQUITY (Textual) [Abstract]
Employee Stock Purchase Plan shares issued during period	32,468
Share-based Payment Arrangement [Member]
EQUITY (Textual) [Abstract]
Vested common stock	345,239
SemCAMS Midstream [Member]
EQUITY (Textual) [Abstract]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	49.00%
Maurepas Pipeline LLC [Member]
EQUITY (Textual) [Abstract]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	49.00%

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

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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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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).

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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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