Segment Information (Details 1) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2015	Jul. 31, 2014	Jan. 31, 2015
Revenues From External Customers And Long Lived Assets [Line Items]
Net sales		$ 145,569	$ 143,591	$ 266,030	$ 264,512
Operating Income		18,234	17,168	25,109	28,089
Total Assets		590,011	591,443	590,011	591,443	$ 583,023
Property, Plant and Equipment, Net		42,723	46,141	42,723	46,141	46,673
United States
Revenues From External Customers And Long Lived Assets [Line Items]
Net sales	[1]	78,772	78,128	143,356	140,407
Operating Income	[1]	7,948	5,254	10,377	4,410
Total Assets		230,209	237,558	230,209	237,558	209,660
Property, Plant and Equipment, Net		25,052	25,169	25,052	25,169	25,950
International
Revenues From External Customers And Long Lived Assets [Line Items]
Net sales	[2]	66,797	65,463	122,674	124,105
Operating Income	[2]	10,286	11,914	14,732	23,679
Total Assets		359,802	353,885	359,802	353,885	373,363
Property, Plant and Equipment, Net		$ 17,671	$ 20,972	$ 17,671	$ 20,972	$ 20,723

[1] The United States operating income included $9.5 million and $5.9 million of unallocated corporate expenses for the three months ended July 31, 2015 and 2014. The United States operating income included $16.6 million and $12.9 million of unallocated corporate expenses for the six months ended July 31, 2015 and 2014.

[2] The International operating income included $10.9 million and $10.6 million of certain intercompany profits related to the Company’s supply chain operations for the three months ended July 31, 2015 and 2014. The International operating income included $19.7 million and $20.1 million of certain intercompany profits related to the Company’s supply chain operations for the six months ended July 31, 2015 and 2014.