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Consolidated Statement of Changes In Shareholders' Equity (Parenthetical) (USD $)
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12 Months Ended | ||
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Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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| Common Stock, Regular | |||
| Paid cash dividends, per share |
$ 0.40us-gaap_CommonStockDividendsPerShareCashPaid / us-gaap_StatementClassOfStockAxis = wti_CommonStockRegularMember |
$ 0.36us-gaap_CommonStockDividendsPerShareCashPaid / us-gaap_StatementClassOfStockAxis = wti_CommonStockRegularMember |
$ 0.32us-gaap_CommonStockDividendsPerShareCashPaid / us-gaap_StatementClassOfStockAxis = wti_CommonStockRegularMember |
| Common Stock, Special | |||
| Paid cash dividends, per share |
$ 0.42us-gaap_CommonStockDividendsPerShareCashPaid / us-gaap_StatementClassOfStockAxis = wti_CommonStockSpecialMember |
$ 0.79us-gaap_CommonStockDividendsPerShareCashPaid / us-gaap_StatementClassOfStockAxis = wti_CommonStockSpecialMember |
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- Definition
Aggregate dividends paid during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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