Represents the consent fee paid to each second lien holder that agrees to support the Restructuring Support Agreement.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Represents the issue price of the debt instrument as a percentage of its face value.

+ References

No definition available.

+ Details

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- Definition

Represents the period within which to file registration statement and complete an exchange offer after closing, , in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Represents loss on the repurchase for the tender premium paid.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Represents loss on write off of discount on notes.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the percentage of consent fee paid to consenting noteholder that agrees under divesture agreement.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The percentage of shareholders concluded a consent solicitation.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
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Balance Type:	credit
Period Type:	instant

- Definition

Increase for accrued, but unpaid interest on the debt instrument for the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Subparagraph (SX 210.4-08.(f))
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Balance Type:	credit
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.5-02.22(a)(1))
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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	na
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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt discount.

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Balance Type:	debit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt premium.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
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LONG-TERM DEBT - 6.75% Senior Notes (Details) - USD ($) $ in Thousands						3 Months Ended		9 Months Ended
	Feb. 15, 2018	Oct. 10, 2017	Sep. 07, 2017	Jul. 25, 2017	Feb. 16, 2017	Sep. 30, 2017	Mar. 31, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Current and long-term debt
Principal amount								$ 625,005		$ 425,005
Accrued and unpaid interest		$ 4,100
Gains (Losses) on Extinguishment of Debt						$ (29,167)			$ (86,065)
6.75% senior notes due 2025
Current and long-term debt
Principal amount			$ 850,000		$ 850,000
Interest rate (as a percent)			6.75%		6.75%			6.75%		6.75%
Net proceeds from issuance					$ 834,100
Redemption price of debt instrument (as a percent)		103.00%
Gains (Losses) on Extinguishment of Debt							$ 56,900
Loss on the repurchase for the tender premium paid							30,900
Loss on the write-off of the discount on notes							$ 26,000
Percentage of holders concluded a consent solicitation				99.00%
Percentage of consent fee paid				2.00%
Consent fee paid				$ 16,900
Principal amount repurchased		$ 425,000
Period within which to complete exchange offer after closing								180 days
Unamortized discount								$ 7,400		$ 8,100
Additional 2025 Notes
Current and long-term debt
Principal amount	$ 200,000
Net proceeds from issuance	$ 202,400
Issue price as a percentage of par value	103.00%
Unamortized premium related to debt issued								$ 5,600
8.625% senior secured second lien notes due 2020
Current and long-term debt
Interest rate (as a percent)					8.625%
Williston Basin Assets \| 6.75% senior notes due 2025
Current and long-term debt
Redemption price of debt instrument (as a percent)			103.00%
Principal amount repurchased			$ 425,000