Acquisitions of and Investments in Businesses and Technologies - Changes in the net carrying value of the investment in SST (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Balance at beginning of year	$ 3,217	$ 3,684
Income from equity investment	83	28	$ 116
Balance at end of year	2,805	3,217	3,684
SST [Member]
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Balance at beginning of year	3,217	3,684	4,063
Income from equity investment	83	28	116
Amortization of intangible assets	(495)	(495)	(495)
Balance at end of year	$ 2,805	$ 3,217	$ 3,684