Income Taxes (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Income tax expense (benefit)	$ 2,849,000	$ 140,000	$ 1,500,000	$ 170,000
Income (Loss) before income taxes	$ 7,877,000	$ 7,026,000	$ 4,317,000	$ 3,917,000
Effective tax rate (percent)	36.20%		34.70%
Reasonably possible decrease in unrecognized tax benefits	$ 9,000		$ 9,000
Accounting Standards Update 2016-09 [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Unrecognized excess tax benefits reversed	$ 172,000		$ 172,000