W&T Offshore, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Notes Tables
Notes Details

Share-Based Compensation and Cash-Based Incentive Compensation (Narrative) (Detail)

v2.4.0.6

Share-Based Compensation and Cash-Based Incentive Compensation (Narrative) (Detail) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended	12 Months Ended			9 Months Ended							9 Months Ended				12 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Dec. 31, 2010	Sep. 30, 2012 LIBOR [Member]	Sep. 30, 2012 Earnings Per Share Targets [Member]	Sep. 30, 2012 Total Shareholder Return [Member]	Sep. 30, 2012 Current Year [Member] Earnings Per Share Targets [Member]	Sep. 30, 2012 Current Year [Member] Total Shareholder Return [Member]	Sep. 30, 2012 2013 [Member] Total Shareholder Return [Member]	Sep. 30, 2012 2014 [Member] Total Shareholder Return [Member]	Sep. 30, 2012 Directors Compensation Plan [Member]	Sep. 30, 2012 Restricted Stock [Member]	Sep. 30, 2011 Restricted Stock [Member]	Sep. 30, 2012 Restricted Stock Units (RSUs) [Member]	Sep. 30, 2012 Minimum [Member]	Sep. 30, 2012 Minimum [Member]	Sep. 30, 2012 Maximum [Member]	Sep. 30, 2012 Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for award under the plans	2,269,745										546,829
Shares granted, grant date fair value												$ 0.4	$ 0.5
Shares Vested, grant date fair value												0.5	0.6
Percentage of employees specified performance requirements	100.00%	100.00%	100.00%				70.00%	10.00%	10.00%	10.00%
Restricted stock units earning per share, minimum					0.00%	0.00%
Restricted stock units earning per share, maximum					100.00%	150.00%
Expected vesting date	Dec. 15, 2014														Dec. 15, 2012		Dec. 15, 2013
Risk-free interest rate, minimum				0.15%
Risk-free interest rate, maximum				0.72%
Expected volatility																33.00%		74.00%
Expected dividend yield																0.00%		2.50%
Correlation of movement of total shareholder return maximum range																(67.00%)		94.00%
Unrecognized share-based compensation expense												$ 0.7		$ 14.0
Recognition period for unrecognized compensation expense												April 2015		November 2014

- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

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-Name Accounting Standards Codification

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Share based compensation arrangement by share based payment award equity instruments other than options granted in period grant date fair value.

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Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Correlation Of Returns

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