Note 1 - Background and Basis of Presentation	12 Months Ended
Dec. 31, 2020
Notes to Financial Statements
Business Description and Basis of Presentation [Text Block]	Note 1 — Background and Basis of Presentation NextDecade Corporation engages in development activities related to the liquefaction and sale of liquefied natural gas (“LNG”). We have focused and continue to focus our development activities on the Rio Grande LNG terminal facility at the Port of Brownsville in southern Texas (the “Terminal”). Our Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). All intercompany accounts and transactions have been eliminated in consolidation.

The entire disclosure for the business description and basis of presentation concepts. Business description describes the nature and type of organization including but not limited to organizational structure as may be applicable to holding companies, parent and subsidiary relationships, business divisions, business units, business segments, affiliates and information about significant ownership of the reporting entity. 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).

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/topic&trid=2134479

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