XML 28 R40.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Derivative Financial Instruments Gains and Losses (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2014 | Mar. 31, 2013
Gain and loss from derivative cash settlements and changes in fair value of derivative contracts |  |  |  |
Derivative cash settlement (loss) gain | $ (28,940) | [1] | $ 11,792 | [1]
Gain (Loss) on Derivative Instruments, Net, Pretax | (97,662) | [2] | (30,572) | [2]
Crude oil |  |  |  |
Gain and loss from derivative cash settlements and changes in fair value of derivative contracts |  |  |  |
Derivative cash settlement (loss) gain | (6,758) |  | (277) |
Derivative (gain) loss | 25,192 |  | 3,789 |
Natural Gas |  |  |  |
Gain and loss from derivative cash settlements and changes in fair value of derivative contracts |  |  |  |
Derivative cash settlement (loss) gain | (13,404) |  | 9,824 |
Derivative (gain) loss | 46,057 |  | 40,069 |
Natural Gas Liquids |  |  |  |
Gain and loss from derivative cash settlements and changes in fair value of derivative contracts |  |  |  |
Derivative cash settlement (loss) gain | (8,778) |  | 2,245 |
Derivative (gain) loss | $ (2,527) |  | $ (1,494) |
[1] | (1) Total derivative cash settlement loss (gain) is reported in the derivative cash settlement (loss) gain line item on the condensed consolidated statements of cash flows within net cash provided by operating activities.
[2] | (2) Total derivative loss is reported in the derivative loss line item on the condensed consolidated statements of cash flows within cash provided by operating activities.

X
- Definition Realized gain (loss) recognized in earnings from the settlement of derivative instruments not designated as hedges. + References No definition available. + Details
Name: | sm_CashSettlementGainLossOnDerivativeInstruments
Namespace Prefix: | sm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_DerivativeInstrumentsGainLossLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959 + Details
Name: | us-gaap_GainLossOnDerivativeInstrumentsNetPretax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 + Details
Name: | us-gaap_UnrealizedGainLossOnDerivatives
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration