Quarterly report pursuant to Section 13 or 15(d)

Acquisitions and Divestitures - Purchase Price Allocation for Acquisition (Details)

v2.4.1.9
Acquisitions and Divestitures - Purchase Price Allocation for Acquisition (Details) (USD $)
In Thousands, unless otherwise specified
 0 Months Ended
Sep. 15, 2014
May 20, 2014
Fairway    
Non-cash consideration:    
Asset retirement obligations - non-current $ 6,124us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilities
/ us-gaap_BusinessAcquisitionAxis
= wti_FairwayPropertiesMember 		 
Total consideration 24,817us-gaap_BusinessCombinationConsiderationTransferred1
/ us-gaap_BusinessAcquisitionAxis
= wti_FairwayPropertiesMember 		 
Fairway | Evaluated Properties Including Equipment    
Cash consideration:    
Oil and natural gas properties and equipment 18,693us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
/ us-gaap_BusinessAcquisitionAxis
= wti_FairwayPropertiesMember
/ us-gaap_RealEstatePropertiesAxis
= wti_EvaluatedPropertiesMember 		 
Woodside Properties    
Cash consideration:    
Oil and natural gas properties and equipment   54,762us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
/ us-gaap_BusinessAcquisitionAxis
= wti_WoodsidePropertiesMember
Non-cash consideration:    
Asset retirement obligations - non-current   10,543us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilities
/ us-gaap_BusinessAcquisitionAxis
= wti_WoodsidePropertiesMember
Asset retirement obligations - current   782us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities
/ us-gaap_BusinessAcquisitionAxis
= wti_WoodsidePropertiesMember
Non-cash consideration   11,325us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred
/ us-gaap_BusinessAcquisitionAxis
= wti_WoodsidePropertiesMember
Total consideration   66,087us-gaap_BusinessCombinationConsiderationTransferred1
/ us-gaap_BusinessAcquisitionAxis
= wti_WoodsidePropertiesMember
Woodside Properties | Evaluated Properties Including Equipment    
Cash consideration:    
Oil and natural gas properties and equipment   52,102us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
/ us-gaap_BusinessAcquisitionAxis
= wti_WoodsidePropertiesMember
/ us-gaap_RealEstatePropertiesAxis
= wti_EvaluatedPropertiesMember
Woodside Properties | Unevaluated Properties    
Cash consideration:    
Oil and natural gas properties and equipment   $ 2,660us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
/ us-gaap_BusinessAcquisitionAxis
= wti_WoodsidePropertiesMember
/ us-gaap_RealEstatePropertiesAxis
= wti_UnevaluatedPropertiesMember