Note 5 - Acquisitions and Divestitures - Purchase Price Allocation (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Aug. 31, 2019
Mobile Bay Properties [Member]
Oil and natural gas properties and other, net - at cost:		$ 192,373
Other assets		4,838
Current liabilities		1,559
Asset retirement obligations		21,684
Other liabilities		$ 4,132
Magnolia Field Acquisition [Member]
Oil and natural gas properties and other, net - at cost:	$ 23,791
Asset retirement obligations	$ 7,842

Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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