Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Apr. 30, 2012	Apr. 30, 2011
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income	$ 6,206	$ 6,156
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	6,940	6,312
Amortization of investment discount	17	20
Non-cash stock compensation expense	519	475
Excess tax benefits for share-based payments	(56)	(285)
Deferred income taxes	103	116
Provision for bad debts	31	42
Loss on the sale of fixed assets	321	168
(Increase) Decrease in:
Accounts receivable	(1,309)	867
Inventories	(159)	(2,308)
Prepaid expenses	2,059	(344)
Other assets	(409)	(30)
Increase (Decrease) in:
Accounts payable	324	1,492
Accrued expenses	321	(1,629)
Deferred compensation	248	86
Other liabilities	480	(18)
Total Adjustments	9,430	4,964
Net Cash Provided by Operating Activities	15,636	11,120
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(5,452)	(10,210)
Proceeds from sale of property, plant and equipment	34	142
Purchases of investment in short-term securities	(14,043)	(51,564)
Dispositions of investment in short-term securities	20,820	36,650
Net Cash Provided by (Used in) Investing Activities	1,359	(24,982)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from issuance of notes payable	0	18,500
Principal payments on notes payable	(3,600)	(3,500)
Dividends paid	(3,395)	(3,158)
Purchase of treasury stock	(2,481)	(2,474)
Proceeds from issuance of treasury stock	31	221
Proceeds from issuance of common stock	161	795
Excess tax benefits for share-based payments	56	285
Net Cash (Used in) Provided by Financing Activities	(9,228)	10,669
Effect of exchange rate changes on cash and cash equivalents	(3)	(117)
Net Increase (Decrease) in Cash and Cash Equivalents	7,764	(3,310)
Cash and Cash Equivalents, Beginning of Period	17,885	18,762
Cash and Cash Equivalents, End of Period	$ 25,649	$ 15,452