Basis Of Financial Statement Preparation	3 Months Ended
Mar. 31, 2020
Basis Of Financial Statement Preparation [Abstract]
Basis Of Financial Statement Preparation	1.Basis of Financial Statement Preparation These unaudited condensed consolidated financial statements should be read in the context of the consolidated financial statements and notes thereto filed with the Securities and Exchange Commission in the Corporation's 2019 Annual Report on Form 10-K. In the opinion of the Corporation, the information furnished herein reflects all known accruals and adjustments necessary for a fair statement of the results for the periods reported herein. All such adjustments are of a normal recurring nature. Prior data has been reclassified in certain cases to conform to the current presentation basis. The Corporation's exploration and production activities are accounted for under the "successful efforts" method.

The entire disclosure for the basis of presentation and significant accounting policies concepts. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS). Accounting policies describe all significant accounting policies of the reporting entity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-URI http://asc.fasb.org/topic&trid=2122369

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