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Long-Term Debt - Long-Term Debt (Parenthetical) (Details) (USD $)
In Millions, unless otherwise specified |
Dec. 31, 2014
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Oct. 24, 2012
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Jun. 10, 2011
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| Debt Instrument [Line Items] | |||
| Aggregate annual maturities of long-term debt, 2015 | 0us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths | ||
| Aggregate annual maturities of long-term debt, 2016 | 0us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo | ||
| Aggregate annual maturities of long-term debt, 2017 | 0us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree | ||
| Aggregate annual maturities of long-term debt, 2018 | 447.0us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour | ||
| Aggregate annual maturities of long-term debt, thereafter | 900.0us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive | ||
| Senior notes interest rate | 8.50%us-gaap_DebtInstrumentInterestRateStatedPercentage | ||
| 8.50% Senior Notes, due June 2019 | |||
| Debt Instrument [Line Items] | |||
| Senior notes interest rate |
8.50%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = wti_EightPointFivePercentSeniorNotesDueJuneTwoThousandNineteenMember |
8.50%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = wti_EightPointFivePercentSeniorNotesDueJuneTwoThousandNineteenMember |
8.50%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_DebtInstrumentAxis = wti_EightPointFivePercentSeniorNotesDueJuneTwoThousandNineteenMember |
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- Definition
Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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