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
Accounting Policies
- Basis of Presentation (Policies)
Notes Tables
Notes Details

Basis of Presentation - Additional Information (Details)

v3.3.0.814

Basis of Presentation - Additional Information (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) $ / bbl $ / MMBTU	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)	Oct. 30, 2015 USD ($)	Oct. 01, 2015 $ / bbl $ / MMBTU	May. 31, 2015 USD ($)
Basis Of Presentation [Line Items]
Net cash provided by operating activities			$ 134,793	$ 419,778
Net cash used in investing activities			$ (259,459)	(452,482)
Percentage of discount from proved reserves			10.00%
Ceiling test write-down of oil and natural gas properties	$ 441,688	$ 0	$ 954,850	0	$ 0
Addition to available cash	$ 100,000		$ 100,000
Second Lien Term Loan
Basis Of Presentation [Line Items]
Term loan								$ 300,000
Debt instrument maturity date			May 15, 2020
Debt instrument interest rate								9.00%
Subsequent Event \| Credit Agreement
Basis Of Presentation [Line Items]
Revolving bank credit facility borrowing base						$ 350,000
SEC Methodology \| Crude Oil
Basis Of Presentation [Line Items]
Weighted price \| $ / bbl			55.73
SEC Methodology \| Natural Gas
Basis Of Presentation [Line Items]
Weighted price \| $ / MMBTU			3.06
Industry Quoted Spot Prices \| Crude Oil \| Subsequent Event
Basis Of Presentation [Line Items]
Average Spot Price \| $ / bbl							41.25
Henry Hub Spot Prices \| Natural Gas \| Subsequent Event
Basis Of Presentation [Line Items]
Average Spot Price \| $ / MMBTU							2.48
Reclassifications
Basis Of Presentation [Line Items]
Net cash provided by operating activities				5,200
Net cash used in investing activities				$ 5,200

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Face (par) amount of debt instrument at time of issuance.

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