Fair values as of the balance sheet date for all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments and which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

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+ Details

Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Assets
Commodity derivatives	$ 131	$ 308
Recurring basis [Member] \| Level 1 [Member]
Assets
Commodity derivatives
Recurring basis [Member] \| Level 2 [Member]
Assets
Commodity derivatives	131	308
Recurring basis [Member] \| Level 3 [Member]
Assets
Commodity derivatives