2.2.0.7 false Fair Value Measurements 0206 - Disclosure - Fair Value Measurements true false false false 1 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ 2 Fair Value Measurements [Abstract] 0 wll_FairValueMeasurementsAbstract wll false na duration Fair Value Measurements. false false false false false true false false false false false false 1 false false false false 0 0 false false false xbrli:stringItemType string Fair Value Measurements. false 3 FAIR VALUE MEASURMENTS 1 us-gaap_FairValueMeasurementInputsDisclosureTextBlock us-gaap true na duration No definition available. false false false false false false false false false false false verboselabel false 1 false false false false 0 0   <div style="font-family: 'Times New Roman',Times,serif"> <div align="left" style="font-size: 10pt; margin-top: 12pt"><b>6. FAIR VALUE MEASURMENTS</b> </div> <div style="margin-top: 6pt"> <table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; text-align: left"> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="3%" nowrap="nowrap" align="left"> </td> <td width="1%"> </td> <td>The Company follows FASB ASC Topic 820, <i>Fair Value Measurement and Disclosure</i>, which establishes a three-level valuation hierarchy for disclosure of fair value measurements. The valuation hierarchy categorizes assets and liabilities measured at fair value into one of three different levels depending on the observability of the inputs employed in the measurement. The three levels are defined as follows:</td> </tr> </table> </div> <div style="margin-top: 6pt"> <table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; text-align: left"> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="8%" style="background: transparent"> </td> <td width="3%" nowrap="nowrap" align="left"><b>•</b></td> <td width="1%"> </td> <td>Level 1: Quoted Prices in Active Markets for Identical Assets — inputs to the valuation methodology are quoted prices (unadjusted) for identical assets or liabilities in active markets.</td> </tr> <tr> <td style="font-size: 6pt"> </td> </tr> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="8%" style="background: transparent"> </td> <td width="3%" nowrap="nowrap" align="left"><b>•</b></td> <td width="1%"> </td> <td>Level 2: Significant Other Observable Inputs — inputs to the valuation methodology include quoted prices for similar assets and liabilities in active markets, and inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the financial instrument.</td> </tr> <tr> <td style="font-size: 6pt"> </td> </tr> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="8%" style="background: transparent"> </td> <td width="3%" nowrap="nowrap" align="left"><b>•</b></td> <td width="1%"> </td> <td>Level 3: Significant Unobservable Inputs — inputs to the valuation methodology are unobservable and significant to the fair value measurement.</td> </tr> </table> </div> <div style="margin-top: 6pt"> <table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; text-align: left"> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="3%" nowrap="nowrap" align="left"> </td> <td width="1%"> </td> <td>A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. The Company reflects transfers between the three levels at the end of the reporting period in which the availability of observable inputs no longer justifies classification in the original level.</td> </tr> </table> </div> <div style="margin-top: 6pt"> <table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; text-align: left"> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="3%" nowrap="nowrap" align="left"> </td> <td width="1%"> </td> <td>The following table presents information about the Company’s financial assets and liabilities measured at fair value on a recurring basis as of June 30, 2010, and indicates the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair values (in thousands):</td> </tr> </table> </div>   </div>  <div style="font-family: 'Times New Roman',Times,serif"> <div align="center"> <table style="font-size: 10pt; text-align: left" cellspacing="0" border="0" cellpadding="0" width="100%">  <tr valign="bottom"> <td width="52%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> </tr> <tr style="font-size: 8pt" valign="bottom"> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2"><b>Total Fair</b></td> <td> </td> </tr> <tr style="font-size: 8pt" valign="bottom"> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2"><b>Value</b></td> <td> </td> </tr> <tr style="font-size: 8pt" valign="bottom"> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"><b>Level 1</b></td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"><b>Level 2</b></td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"><b>Level 3</b></td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"><b>June 30, 2010</b></td> <td> </td> </tr>   <tr valign="bottom" style="background: #cceeff"> <td> <div style="margin-left:15px; text-indent:-15px"><b>Financial Assets</b> </div></td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr> <tr valign="bottom"> <td> <div style="margin-left:15px; text-indent:-15px">Commodity derivatives — current </div></td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">7,440</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">7,440</td> <td> </td> </tr> <tr valign="bottom" style="background: #cceeff"> <td> <div style="margin-left:15px; text-indent:-15px">Commodity derivatives — non-current </div></td> <td> </td> <td> </td> <td align="right">—</td> <td> </td> <td> </td> <td> </td> <td align="right">8,580</td> <td> </td> <td> </td> <td> </td> <td align="right">—</td> <td> </td> <td> </td> <td> </td> <td align="right">8,580</td> <td> </td> </tr> <tr style="font-size: 1px"> <td> <div style="margin-left:15px; text-indent:-15px">  </div></td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> </tr> <tr valign="bottom"> <td> <div style="margin-left:30px; text-indent:-15px">Total financial assets </div></td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">16,020</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">16,020</td> <td> </td> </tr> <tr style="font-size: 1px"> <td> <div style="margin-left:15px; text-indent:-15px">  </div></td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> </tr> <tr valign="bottom"> <td> <div style="margin-left:15px; text-indent:-15px">  </div></td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr> <tr valign="bottom" style="background: #cceeff"> <td> <div style="margin-left:15px; text-indent:-15px"><b>Financial Liabilities</b> </div></td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> </tr> <tr valign="bottom"> <td> <div style="margin-left:15px; text-indent:-15px">Commodity derivatives — current </div></td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">26,269</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">26,269</td> <td> </td> </tr> <tr valign="bottom" style="background: #cceeff"> <td> <div style="margin-left:15px; text-indent:-15px">Commodity derivatives — non-current </div></td> <td> </td> <td> </td> <td align="right">—</td> <td> </td> <td> </td> <td> </td> <td align="right">73,750</td> <td> </td> <td> </td> <td> </td> <td align="right">—</td> <td> </td> <td> </td> <td> </td> <td align="right">73,750</td> <td> </td> </tr> <tr style="font-size: 1px"> <td> <div style="margin-left:15px; text-indent:-15px">  </div></td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> </tr> <tr valign="bottom"> <td> <div style="margin-left:30px; text-indent:-15px">Total financial liabilities </div></td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">100,019</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">100,019</td> <td> </td> </tr> <tr style="font-size: 1px"> <td> <div style="margin-left:15px; text-indent:-15px">  </div></td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> </tr>  </table> </div> <div style="margin-top: 6pt"> <table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; text-align: left"> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="1%" nowrap="nowrap" align="left"> </td> <td width="1%"> </td> <td>The following methods and assumptions were used to estimate the fair values of the assets and liabilities in the table above:</td> </tr> <tr> <td style="font-size: 6pt"> </td> </tr> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="1%" nowrap="nowrap" align="left"> </td> <td width="1%"> </td> <td><i>Commodity Derivative Instruments</i>. Commodity derivative instruments consist primarily of costless collars for crude oil and natural gas. The Company’s costless collars are valued using industry-standard models, which are based on a market approach. These models consider various assumptions, including quoted forward prices for commodities, time value, volatility factors and contractual prices for the underlying instruments, as well as other relevant economic measures. Substantially all of these assumptions are observable in the marketplace throughout the full term of the contract, can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace, and are therefore designated as Level 2 within the valuation hierarchy. The discount rates used in the fair values of these instruments include a measure of either the Company’s or the counterparty’s nonperformance risk, as appropriate. The Company utilizes counterparties’ valuations to assess the reasonableness of its own valuations.</td> </tr> <tr> <td style="font-size: 6pt"> </td> </tr> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="1%" nowrap="nowrap" align="left"> </td> <td width="1%"> </td> <td><i>Non-Recurring Fair Value Measurements</i>. The Company applies the provisions of the fair value measurement standard to its non-recurring, non-financial measurements including business combinations, proved oil and gas property impairments and asset retirement obligations. These assets and liabilities are not measured at fair value on an ongoing basis but are subject to fair value adjustments only in certain circumstances. The following table presents information about the Company’s non-financial assets and liabilities measured at fair value on a non-recurring basis as of June 30, 2010, and indicates the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair values (in thousands):</td> </tr> </table> </div> <div align="center"> <table style="font-size: 10pt; text-align: left" cellspacing="0" border="0" cellpadding="0" width="100%">  <tr valign="bottom"> <td width="40%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> <td width="5%"> </td> <td width="1%"> </td> </tr> <tr style="font-size: 8pt" valign="bottom"> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2"><b>Pre-tax (Gain)</b></td> <td> </td> </tr> <tr style="font-size: 8pt" valign="bottom"> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2"><b>Net Carrying</b></td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2"><b>Loss Six</b></td> <td> </td> </tr> <tr style="font-size: 8pt" valign="bottom"> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2"><b>Value as of</b></td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="10" style="border-bottom: 1px solid #000000"><b>Fair Value Measurements Using</b></td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2"><b>Months Ended</b></td> <td> </td> </tr> <tr style="font-size: 8pt" valign="bottom"> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"><b>June 30, 2010</b></td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"><b>Level 1</b></td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"><b>Level 2</b></td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"><b>Level 3</b></td> <td> </td> <td> </td> <td nowrap="nowrap" align="center" colspan="2" style="border-bottom: 1px solid #000000"><b>June 30, 2010</b></td> <td> </td> </tr>   <tr valign="bottom"> <td> <div style="margin-left:15px; text-indent:-15px">Asset retirement obligations </div></td> <td> </td> <td align="left">$</td> <td align="right">633</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">626</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> </tr> <tr style="font-size: 1px"> <td> <div style="margin-left:15px; text-indent:-15px">  </div></td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 1px solid #000000"> </td> <td> </td> </tr> <tr valign="bottom"> <td> <div style="margin-left:30px; text-indent:-15px">Total non-recurring assets at fair value </div></td> <td> </td> <td align="left">$</td> <td align="right">633</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">626</td> <td> </td> <td> </td> <td align="left">$</td> <td align="right">—</td> <td> </td> </tr> <tr style="font-size: 1px"> <td> <div style="margin-left:15px; text-indent:-15px">  </div></td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> <td> </td> <td nowrap="nowrap" colspan="2" align="right" style="border-top: 3px double #000000"> </td> <td> </td> </tr>  </table> </div> <div style="margin-top: 6pt"> <table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt; text-align: left"> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="1%" nowrap="nowrap" align="left"> </td> <td width="1%"> </td> <td>The following methods and assumptions were used to estimate the fair values of the non-financial assets and liabilities in the table above:</td> </tr> <tr> <td style="font-size: 6pt"> </td> </tr> <tr valign="top" style="font-size: 10pt; color: #000000; background: transparent"> <td width="1%" nowrap="nowrap" align="left"> </td> <td width="1%"> </td> <td><i>Asset Retirement Obligations</i>. The Company estimates the fair value of asset retirement obligations at the point they are incurred by calculating the present value of estimated future plug and abandonment costs. Such present value calculations use internally developed cash flow models, which are based on an income approach, and include various assumptions such as estimated amounts and timing of abandonment cash flows, the Company’s credit-adjusted risk-free rate and future inflation rates. Given the unobservable nature of most of these inputs, the initial measurement of asset retirement obligation liabilities is deemed to use Level 3 inputs.</td> </tr> </table> </div> </div>  <!-- Begin Block Tagged Note false false false us-types:textBlockItemType textblock This element represents the disclosure related to the fair value measurement of assets and liabilities which includes [financial] instruments measured at fair value that are classified in stockholders' equity. Such assets and liabilities may be measured on a recurring or nonrecurring basis. The disclosures which may be required or desired include: (1) for assets and liabilities measured on a recurring basis, disclosure may include: (a) the fair value measurements at the reporting date; (b) the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets or liabilities (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3); (c) for fair value measurements using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (i) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (ii) purchases, sales, issuances, and settlements (net); (iii) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs); (d) the amount of the total gains or losses for the period in subparagraph (c) (i) above included in earnings (or changes in net assets) that are attributable to the change in unrealized gains or losses relating to those assets and liabilities still held at the reporting date and a description of where those unrealized gains or losses are reported in the statement of income (or activities); (e) the valuation technique(s) used to measure fair value and a discussion of changes in valuation techniques, if any, during the period and (2) for assets and liabilities that are measured at fair value on a nonrecurring basis (for example, impaired assets) disclosure may include, in addition to (a) above: (a) the reasons for the fair value measurements recorded; (b) the same as (b) above; (c) for fair value measurements using significant unobservable inputs (Level 3), a description of the inputs and the information used to develop the inputs; and (d) the valuation technique(s) used to measure fair value and a discussion of changes, if any, in the valuation technique(s) used to measure similar assets and/or liabilities in prior periods. 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