Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Condensed Consolidated Statements of Operations [Abstract]
Revenues	$ 37,354	$ 32,370	$ 17,458	$ 69,724	$ 22,655
Cost of sales	33,716	29,780	23,602	63,496	37,602
Gross profit (loss)	3,638	2,590	(6,144)	6,228	(14,947)
Selling, general and administrative expenses	6,294	9,151	6,537	15,445	13,947
Restructuring and impairment charges	(120)	6,650	267	6,530	1,147
Operating loss	(2,536)	(13,211)	(12,948)	(15,747)	(30,041)
Interest expense	(3,212)	(2,502)	(167)	(5,714)	(463)
Loss on change in fair market value for warrant liability	(3,452)	22,128	0	18,676	0
Other income	230	115	134	345	358
Loss before income taxes	(2,066)	(37,726)	(12,981)	(39,792)	(30,146)
Income tax provision (benefit)	504	132	(1)	636	(3)
Net loss	(2,570)	(37,858)	(12,980)	(40,428)	(30,143)
Less Net loss attributable to noncontrolling interest in JV	0	0	(189)	0	(405)
Net loss attributable to FreightCar America	$ (2,570)	$ (37,858)	$ (12,791)	$ (40,428)	$ (29,738)
Net loss per common share attributable to FreightCar America- basic	$ (0.13)	$ (1.89)	$ (0.97)	$ (2.01)	$ (2.26)
Net loss per common share attributable to FreightCar America- diluted	$ (0.13)	$ (1.89)	$ (0.97)	$ (2.01)	$ (2.26)
Weighted Average Number of Shares Outstanding, Basic	20,160,410	20,001,505	12,405,011	20,084,199	12,385,946
Weighted Average Number of Shares Outstanding, Diluted	20,160,410	20,001,505	12,405,011	20,084,199	12,385,946