CONSOLIDATED STATEMENTS OF EARNINGS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
CONSOLIDATED STATEMENTS OF EARNINGS
REVENUES	$ 482,153	$ 892,815	$ 675,047
Cost of revenues	399,715	743,490	528,336
GROSS PROFIT	82,438	149,325	146,711
Selling, general and administrative expenses	40,710	41,764	32,478
Impairment losses	1,491	584	1,979
INCOME FROM OPERATIONS	40,237	106,977	112,254
Other income, net	6,981	5,648	2,278
INCOME BEFORE INCOME TAXES	47,218	112,625	114,532
Income tax benefit (expense)	4,651	(40,279)	(37,106)
NET INCOME	51,869	72,346	77,426
Net (loss) income attributable to non-controlling interests	(167)	335	7,098
NET INCOME ATTRIBUTABLE TO THE STOCKHOLDERS OF ARGAN, INC.	52,036	72,011	70,328
Foreign currency translation adjustments	(1,768)	2,184	(197)
COMPREHENSIVE INCOME ATTRIBUTABLE TO THE STOCKHOLDERS OF ARGAN, INC.	$ 50,268	$ 74,195	$ 70,131
EARNINGS PER SHARE ATTRIBUTABLE TO THE STOCKHOLDERS OF ARGAN, INC.
Basic (in Dollars per share)	$ 3.34	$ 4.64	$ 4.67
Diluted (in Dollars per share)	$ 3.32	$ 4.56	$ 4.50
WEIGHTED AVERAGE NUMBER OF SHARES OUTSTANDING
Basic (in shares)	15,569	15,522	15,066
Diluted (in shares)	15,693	15,780	15,625
CASH DIVIDENDS PER SHARE (Note 15)	$ 1.00	$ 1.00	$ 1.00