Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jul. 31, 2012	Jul. 31, 2011
OPERATING ACTIVITIES:
Net income	$ 30,591	$ 28,177
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	6,036	4,159
Gain on acquisition-related contingent liability settlement	(508)	0
Change in fair value of acquisition-related contingent consideration	508	(93)
Earnings of equity investee	57	27
Deferred income taxes	(590)	1,352
Share-based compensation expense	1,570	984
Change in operating assets and liabilities:
Accounts receivable	10,798	(3,192)
Inventories	4,368	(6,546)
Prepaid expense and other assets	(990)	(932)
Operating liabilities	(7,407)	2,427
Other operating activities, net	29	(100)
Net cash provided by operating activities	44,462	26,263
INVESTING ACTIVITIES:
Capital expenditures	(16,870)	(11,000)
Sales of short-term investments	0	1,000
Other investing activities, net	22	(501)
Net cash used in investing activities	(16,848)	(10,501)
FINANCING ACTIVITIES:
Dividends paid	(7,618)	(6,509)
Payments of acquisition-related contingent liability	(1,867)	0
Other financing activities, net	163	62
Net cash used in financing activities	(9,322)	(6,447)
Effect of exchange rate changes on cash	(21)	100
Net increase in cash and cash equivalents	18,271	9,415
Cash and cash equivalents at beginning of year	25,842	37,563
Cash and cash equivalents at end of year	$ 44,113	$ 46,978