Consolidated Statements of Operations (USD $)	12 Months Ended
	Jan. 31, 2013	Jan. 31, 2012
Net revenues
Net revenues	$ 278,635,000	$ 141,850,000
Cost of revenues
Cost of revenues	228,500,000	118,748,000
Gross profit	50,135,000	23,102,000
Selling, general and administrative expenses	14,350,000	11,186,000
Income from operations	35,785,000	11,916,000
Other (expense) income, net	(43,000)	48,000
Income from continuing operations before income taxes	35,742,000	11,964,000
Income tax expense	13,640,000	4,556,000
Income from continuing operations	22,102,000	7,408,000
Discontinued operations
(Loss) income from discontinued operations before income tax benefit (including gain on disposal of $1,312,000 for the year ended January 31, 2012, see Note 18)	(405,000)	282,000
Income tax benefit	120,000	1,280,000
(Loss) income from discontinued operations	(285,000)	1,562,000
Net income	21,817,000	8,970,000
Less - Loss attributable to noncontrolling interest (see Note 4)	1,448,000	302,000
Net income attributable to Argan, Inc. stockholders	23,265,000	9,272,000
Continuing Operations (see Note 15)
Basic	$ 1.71	$ 0.57
Diluted	$ 1.67	$ 0.56
Discontinued Operations
Basic	$ (0.02)	$ 0.11
Diluted	$ (0.02)	$ 0.11
Net Income
Basic	$ 1.69	$ 0.68
Diluted	$ 1.65	$ 0.67
Weighted average number of shares outstanding:
Basic	13,784,000	13,612,000
Diluted	14,116,000	13,792,000
Cash dividend per common share	$ 0.60	$ 0.50
Telecommunications Infrastructure Services
Net revenues
Net revenues	17,308,000	9,331,000
Cost of revenues
Cost of revenues	13,683,000	7,555,000
Power Industry Services
Net revenues
Net revenues	261,327,000	132,519,000
Cost of revenues
Cost of revenues	$ 214,817,000	$ 111,193,000