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

Note 9 - Derivative Financial Instruments - Summary of Open Commodity Derivative Contracts (Details)

Note 9 - Derivative Financial Instruments - Summary of Open Commodity Derivative Contracts (Details)	12 Months Ended
	Dec. 31, 2020 BTU $ / shares bbl
NYMEX Natural Gas Open Swap Contracts [Member] \| Natural Gas, Open Swap Contracts, One [Member]
Notional Quantity	3,650,000
Strike Price (in dollars per share)	$ 2.62
Notional Quantity (MMBtu/day) (British Thermal Unit) \| BTU	10,000
NYMEX Natural Gas Open Swap Contracts [Member] \| Natural Gas, Open Swap Contracts, Two [Member]
Notional Quantity	620,000
Strike Price (in dollars per share)	$ 2.79
Notional Quantity (MMBtu/day) (British Thermal Unit) \| BTU	20,000
NYMEX Natural Gas Open Swap Contracts [Member] \| Natural Gas, Open Swap Contracts, Three [Member]
Notional Quantity	840,000
Strike Price (in dollars per share)	$ 2.79
Notional Quantity (MMBtu/day) (British Thermal Unit) \| BTU	30,000
NYMEX Natural Gas Open Swap Contracts [Member] \| Natural Gas, Open Swap Contracts, Four [Member]
Notional Quantity	970,075
Strike Price (in dollars per share)	$ 2.69
Notional Quantity (MMBtu/day) (British Thermal Unit) \| BTU	10,544
NYMEX Crude Oil Swap [Member] \| Open Crude Oil Derivative Contracts 1 [Member]
Notional Quantity (Bbls/day) (Barrel of Oil) \| bbl	4,000
Notional Quantity	1,460,000
Strike Price (in dollars per share)	$ 42.06
NYMEX Crude Oil Swap [Member] \| Open Crude Oil Derivative Contracts 2 [Member]
Notional Quantity (Bbls/day) (Barrel of Oil) \| bbl	3,000
Notional Quantity	177,000
Strike Price (in dollars per share)	$ 42.98
NYMEX Crude Oil Swap [Member] \| Open Crude Oil Derivative Contracts 3 [Member]
Notional Quantity (Bbls/day) (Barrel of Oil) \| bbl	2,044
Notional Quantity	188,006
Strike Price (in dollars per share)	$ 42.33
NYMEX Crude Oil Collar [Member] \| Open Crude Oil Derivative Contracts 1 [Member]
Notional Quantity (Bbls/day) (Barrel of Oil) \| bbl	1,770
Notional Quantity	750,422
NYMEX Crude Oil Collar [Member] \| Open Crude Oil Derivative Contracts 1 [Member] \| Put Option [Member]
Strike Price (in dollars per share)	$ 35.00
NYMEX Crude Oil Collar [Member] \| Open Crude Oil Derivative Contracts 1 [Member] \| Call Option [Member]
Strike Price (in dollars per share)	$ 50.00
NYMEX Crude Oil Collar [Member] \| Open Crude Oil Derivative Contracts 2 [Member]
Notional Quantity (Bbls/day) (Barrel of Oil) \| bbl	2,000
Notional Quantity	184,000
NYMEX Crude Oil Collar [Member] \| Open Crude Oil Derivative Contracts 2 [Member] \| Put Option [Member]
Strike Price (in dollars per share)	$ 35.00
NYMEX Crude Oil Collar [Member] \| Open Crude Oil Derivative Contracts 2 [Member] \| Call Option [Member]
Strike Price (in dollars per share)	$ 48.50
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, One [Member]
Notional Quantity	29,200,000
Notional Quantity (MMBtu/day) (British Thermal Unit) \| BTU	40,000
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, One [Member] \| Put Option [Member]
Strike Price (in dollars per share)	$ 1.83
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, One [Member] \| Call Option [Member]
Strike Price (in dollars per share)	$ 3.00
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, Two [Member]
Notional Quantity	10,950,000
Notional Quantity (MMBtu/day) (British Thermal Unit) \| BTU	30,000
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, Two [Member] \| Put Option [Member]
Strike Price (in dollars per share)	$ 2.18
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, Two [Member] \| Call Option [Member]
Strike Price (in dollars per share)	$ 3.00
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, Three [Member]
Notional Quantity	1,770,000
Notional Quantity (MMBtu/day) (British Thermal Unit) \| BTU	30,000
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, Three [Member] \| Put Option [Member]
Strike Price (in dollars per share)	$ 2.20
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, Three [Member] \| Call Option [Member]
Strike Price (in dollars per share)	$ 4.50
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, Four [Member]
Notional Quantity	92,000
Notional Quantity (MMBtu/day) (British Thermal Unit) \| BTU	10,000
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, Four [Member] \| Put Option [Member]
Strike Price (in dollars per share)	$ 2.25
NYMEX Natural Gas Two Way Collars [Member] \| Natural Gas, Open Collar Contracts, Four [Member] \| Call Option [Member]
Strike Price (in dollars per share)	$ 3.40
NYMEX Natural Gas, Open Call Contracts [Member] \| Natural Gas, Open Call Contracts, One [Member]
Notional Quantity	27,960,000
Strike Price (in dollars per share)	$ 3.00
Notional Quantity (MMBtu/day) (British Thermal Unit) \| BTU	40,000