Quaterly Information (Unaudited) (Details) $ / shares in Units, $ in Thousands	3 Months Ended																7 Months Ended		12 Months Ended
	Jan. 31, 2019 USD ($) $ / shares		Oct. 31, 2018 USD ($) $ / shares		Jul. 31, 2018 USD ($) $ / shares		Apr. 30, 2018 USD ($) $ / shares		Jan. 31, 2018 USD ($) $ / shares		Oct. 31, 2017 USD ($) $ / shares		Jul. 31, 2017 USD ($) $ / shares		Apr. 30, 2017 USD ($) $ / shares		Aug. 31, 2018 USD ($)	Aug. 31, 2017 USD ($)	Jan. 31, 2019 USD ($) percentagepoints $ / shares		Jan. 31, 2018 USD ($) $ / shares		Jan. 31, 2017 USD ($) $ / shares
Quarterly Information [Line Items]
Net sales	$ 88,022	[1]	$ 104,833	[1],[2]	$ 102,684	[2]	$ 111,129	[2]	$ 95,823	[1]	$ 101,349	[1],[2]	$ 86,610	[2]	$ 93,535	[2]			$ 406,668	[3],[4]	$ 377,317	[3],[4]	$ 277,395	[4]
Gross Profit	25,290		32,653		34,608		39,998		29,763		33,333		26,513		31,956				132,549		121,565		78,190
Operating Income	3,361		13,612		16,629		21,531	[5]	11,422		17,829		11,700		18,219				55,133	[6]	59,170	[6]	28,413	[7]
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	3,584		14,286		16,490		27,210	[8]	11,565		17,795		11,637		17,989				61,570		58,986		27,853
Net income attributable to Raven Industries, Inc.	$ 2,950	[9]	$ 13,032	[9]	$ 13,677	[9]	$ 22,135	[9]	$ 8,441		$ 11,998		$ 8,235		$ 12,348				$ 51,794	[9]	$ 41,022		$ 20,191
Net income per share - basic (in usd per share) | $ / shares	$ 0.08	[10]	$ 0.36	[10]	$ 0.38	[10]	$ 0.62	[10]	$ 0.24	[10]	$ 0.33	[10]	$ 0.23	[10]	$ 0.34	[10]			$ 1.44	[10]	$ 1.14	[10]	$ 0.56
Net income per share - diluted (in usd per share) | $ / shares	0.08	[10]	0.36	[10]	0.38	[10]	0.61	[10]	0.23	[10]	0.33	[10]	0.23	[10]	0.34	[10]			1.42	[10]	1.13	[10]	$ 0.56
Common Stock, Dividends, Per Share, Cash Paid | $ / shares	$ 0.13		$ 0.13		$ 0.13		$ 0.13		$ 0.13		$ 0.13		$ 0.13		$ 0.13				$ 0.52		$ 0.52
Equity Method Investment, Realized Gain (Loss) on Disposal																			$ 5,785		$ 0		$ 0
Effective tax rate change, excluding discrete items | percentagepoints																			10
Impact of TCJA, excluding discrete items																			$ 6,218
Applied Technology
Quarterly Information [Line Items]
Net sales																			129,749		124,688		105,217
Engineered Films
Quarterly Information [Line Items]
Net sales																			226,574		213,298		$ 138,855
SST | Applied Technology | Other Nonoperating Income (Expense)
Quarterly Information [Line Items]
Equity Method Investment, Realized Gain (Loss) on Disposal							$ 5,785												5,785
CLI | Engineered Films
Quarterly Information [Line Items]
Net sales																	$ 21,568	$ 4,109
Hurricane Recovery Film | Engineered Films
Quarterly Information [Line Items]
Net sales	$ 4,065		$ 1,510				8,919		$ 15,801		$ 8,424								14,494		$ 24,225
Charitable Gift
Quarterly Information [Line Items]
Loss Contingency, Loss in Period							$ 4,503												$ 4,503

[1] In the third and fourth quarter of fiscal year 2018 hurricane recovery film net sales were $8,424 and $15,801, respectively. Sales of hurricane recovery film in fiscal year 2019 were $8,919, $1,510 and $4,065 for the first, third, and fourth quarters, respectively.

[2] In September of fiscal year 2018, the Company acquired CLI. For the first seven months of fiscal 2019 CLI contributed a total of $21,568 in sales and for the first seven months of fiscal 2018 the division generated $4,109 in sales to CLI as a customer.

[3] In September of fiscal year 2018, the Company acquired CLI. For the first seven months of fiscal 2019 CLI contributed a total of $21,568 in sales and for the first seven months of fiscal 2018 the division generated $4,109 in sales to CLI as a customer. Additionally, sales of hurricane recovery film in fiscal years 2019 and 2018 were $14,494 and $24,225, respectively

[4] Aerostar divested its client private business in the first quarter of fiscal 2019. Net sales from the client private business were $283, $5,592, and $5,886 in fiscal years 2019, 2018 and 2017, respectively. Operating profits for the client private business were not material for these periods.

[5] In the first quarter of fiscal 2019, the Company incurred a $4,503 operating expense related to the previously announced gift to SDSU.

[6] Fiscal 2019 administrative expenses included a $4,503 expense related to the previously announced gift to SDSU and approximately $4,000 of expenses related to Project Atlas. Project Atlas related expenses in fiscal 2018 were approximately $900.

[7] Fiscal year 2017 included inventory write-downs of $2,278 for Aerostar as a result of discontinuing sales activities for a specific radar product line within its business

[8] In the first quarter of fiscal 2019, the Company sold its ownership interest in SST and recognized a gain on sale of $5,785 reported as nonoperating income in "Other income (expense), net" in the Consolidated Statements of Income and Comprehensive Income.

[9] The TCJA, effective January 1, 2018, had a favorable impact to the Company's effective tax rate. Excluding discrete items, the Company's effective tax rate decreased approximately 10 percentages points resulting in tax savings of $6,218 in fiscal year 2019.

[10] Net income per share is computed discretely by quarter and may not add to the full year.