Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Revenues	$ 0	$ 0
Operating Expenses
General and administrative expenses	20,213	22,548
Invitation to Bid Contract Costs	0	10,163
Land option and lease expenses	1,603	2,039
Depreciation expense	196	251
Total operating expenses	22,012	35,001
Total operating loss	(22,012)	(35,001)
Other income (expense)
Gain (loss) on Common Stock Warrant liabilities	7,870	(2,657)
Loss on redemption of investment securities	(412)	0
Interest income, net	243	1,718
Other	(18)	69
Total other income	7,683	(870)
Net loss attributable to NextDecade Corporation	(14,329)	(35,871)
Preferred stock dividends	(14,327)	(11,164)
Deemed dividends on Series A Convertible Preferred Stock	(128)	(1,517)
Net loss attributable to common stockholders	$ (28,784)	$ (48,552)
Net loss per common share - basic and diluted (in dollars per share)	$ (0.24)	$ (0.45)
Weighted average shares outstanding - basic and diluted (in shares)	117,524	109,057