1.0.0.3 false Accounting Pronouncements Not Yet Adopted false 1 $ false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 USDPerShare Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 2 NOTES TO CONSOLIDATED FINANCIAL STATEMENTS 0 wlt_NotesToConsolidatedFinancialsAbstract wlt false na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false No definition available. false 3 Accounting Pronouncements Not Yet Adopted 1 us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock us-gaap true na duration string No definition available. false false false false false false false false false 1 false false 0 0 <table style="font-size:10pt; font-family:'Times New Roman',times,serif;"> <tr> <td> NOTE 18Accounting Pronouncements Not Yet Adopted         In January 2010, the FASB amended its guidance in ASC Topic 932 "Extractive Activities-Oil and Gas," expanding the definition of oil and gas producing activities to include the extraction of saleable hydrocarbons from oil sands, shale and coalbeds, clarifying that entities' equity method investments must be considered in oil and gas activities, and requiring new disclosures. This updated guidance is generally effective for annual periods ending on or after December 31, 2009, but for entities becoming subject to this standard because of the change in the definition of significant oil and gas producing activities, disclosure is required for periods beginning after December 31, 2009. Since the Company is subject to this guidance because it extracts hydrocarbons from coalbeds, disclosures under ASC Topic 932 will be provided for its 2010 reporting period, as required. The Company does not expect the effect of applying the amendment to have a material effect on our operating results or financial condition. </td></tr></table> NOTE 18Accounting Pronouncements Not Yet Adopted         In January 2010, the FASB amended its guidance in ASC false false No definition available. No authoritative reference available. false false 1 2 false UnKnown UnKnown UnKnown false true