Early Termination Penalty for Rig Contract Cancellation

No definition available.

Name:	sm_EarlyTerminationPenaltyforRigContractCancellation
Namespace Prefix:	sm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Total amount of water committed to be supplied under existing contracts or agreements.

+ References

No definition available.

+ Details

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Data Type:	num:volumeItemType
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Period Type:	instant

- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Total amount of product committed to be supplied under existing contracts or agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1207
-Paragraph (a)
-Subparagraph (2)

+ Details

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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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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Commitments and Contingencies (Details) MMcf in Thousands, $ in Millions	May 03, 2017 USD ($)	Mar. 31, 2017 USD ($) MMcf MMBbls	Dec. 31, 2016 USD ($) MMcf MMBbls
Gas gathering and Oil and Gas Through-put Commitments [Member]
Other Commitments [Line Items]
Contractual Obligation \| $		$ 458.8
Water Disposal Agreement [Member]
Other Commitments [Line Items]
Water Delivery Commitments and Contracts, Remaining Contractual Volume \| MMBbls		25.4
Natural Gas Transportation Commitment [Member]
Other Commitments [Line Items]
Oil and Gas Delivery Commitments and Contracts, Remaining Contractual Volume \| MMcf		915
Crude Oil Transportation Commitment [Member]
Other Commitments [Line Items]
Oil and Gas Delivery Commitments and Contracts, Remaining Contractual Volume \| MMBbls		17
Subsequent Event [Member] \| Drilling Rig Leasing Contracts [Member]
Other Commitments [Line Items]
Contractual Obligation \| $	$ 30.1
Scenario, Forecast [Member] \| Subsequent Event [Member] \| Drilling Rig Leasing Contracts [Member]
Other Commitments [Line Items]
Early Termination Penalty for Rig Contract Cancellation \| $	$ 19.0
Non-Operated Eagle Ford Divestiture 2017 [Member] \| Gas gathering and Oil and Gas Through-put Commitments [Member]
Other Commitments [Line Items]
Contractual Obligation \| $			$ 501.9
Non-Operated Eagle Ford Divestiture 2017 [Member] \| Natural Gas Transportation Commitment [Member]
Other Commitments [Line Items]
Oil and Gas Delivery Commitments and Contracts, Remaining Contractual Volume \| MMcf			514
Non-Operated Eagle Ford Divestiture 2017 [Member] \| Crude Oil Transportation Commitment [Member]
Other Commitments [Line Items]
Oil and Gas Delivery Commitments and Contracts, Remaining Contractual Volume \| MMBbls			52
Non-Operated Eagle Ford Divestiture 2017 [Member] \| NGL Contracts [Member]
Other Commitments [Line Items]
Oil and Gas Delivery Commitments and Contracts, Remaining Contractual Volume \| MMBbls			13