Net Income per Share Schedule of calculation of numerator and denominator in earnings per share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011
Numerator:
Net income attributable to Raven Industries, Inc.	$ 52,545	$ 50,569	$ 40,537
Denominator:
Weighted average common shares outstanding	36,290,329	36,182,042	36,083,342
Weighted average stock units outstanding	54,929	52,448	50,450
Denominator for basic calculation	36,345,258	36,234,490	36,133,792
Weighted average common shares outstanding	36,290,329	36,182,042	36,083,342
Weighted average stock units outstanding	54,929	52,448	50,450
Dilutive impact of stock options	188,166	218,730	85,796
Denominator for diluted calculation	36,533,424	36,453,220	36,219,588
Net income per share - basic	$ 1.45	$ 1.40	$ 1.12
Net income per share - diluted	$ 1.44	$ 1.39	$ 1.12