Debt Instrument, Repurchase Premium

No definition available.

Name:	sm_DebtInstrumentRepurchasePremium
Namespace Prefix:	sm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

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+ Details

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Period Type:	instant

- 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.

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+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

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Period Type:	duration

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

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+ Details

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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Senior Secured Notes (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
Senior Secured Notes (Details) - USD ($) $ in Thousands	Jun. 17, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Senior Secured Notes [Line Items]
Loss on extinguishment of debt		$ 0	$ (67,226)	$ 0	$ (67,605)
10.0% Senior Secured Notes due 2025
Senior Secured Notes [Line Items]
Senior Secured Notes, repurchased face amount	$ 446,700
Senior Notes, interest rate, stated percentage	10.00%
Senior Secured Notes, Redemption Price, Percentage	107.50%
Loss on extinguishment of debt	$ 67,200
Debt Instrument, Repurchase Premium	33,500
10.0% Senior Secured Notes due 2025 \| Accelerated Unamortized Debt Discount
Senior Secured Notes [Line Items]
Write off of Deferred Debt Issuance Cost	26,300
10.0% Senior Secured Notes due 2025 \| Accelerated unamortized deferred financing costs
Senior Secured Notes [Line Items]
Write off of Deferred Debt Issuance Cost	$ 7,400