Consolidated Statements of Cash Flows (USD $) In Thousands	3 Months Ended
	Apr. 30, 2011	Apr. 30, 2010
OPERATING ACTIVITIES:
Net income	$ 15,716	$ 12,945
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	1,985	1,738
Change in fair value of acquisition-related contingent consideration	31	160
Deferred income taxes	845	(590)
Share-based compensation expense	392	201
Change in operating assets and liabilities:
Accounts receivable	(10,468)	(9,482)
Inventories	(1,833)	(3,058)
Prepaid expenses and other assets	(1,117)	(925)
Operating liabilities	5,463	9,458
Other operating activities, net	(6)	(111)
Net cash provided by operating activities	11,008	10,336
INVESTING ACTIVITIES:
Capital expenditures	(3,585)	(1,585)
Purchase of short-term investments	0	(500)
Sale of short-term investments	500	1,000
Payments related to business acquisitions	(8)	(148)
Other investing activities, net	(264)	54
Net cash used in investing activities	(3,357)	(1,179)
FINANCING ACTIVITIES:
Dividends paid	(3,254)	(2,885)
Other financing activities, net	100	0
Net cash used in financing activities	(3,154)	(2,885)
Effect of exchange rate changes on cash	65	16
Net increase in cash and cash equivalents	4,562	6,288
Cash and cash equivalents:
Beginning of period	37,563	40,684
End of period	$ 42,125	$ 46,972