Condensed Consolidated Statements of Cash Flows (USD $)	9 Months Ended
	Apr. 30, 2015	Apr. 30, 2014
Cash flows from operating activities:
Net income	$ 17,770,000	$ 17,163,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of property, plant and equipment	4,896,000	5,033,000
Amortization of intangible assets with finite lives	4,682,000	4,724,000
Amortization of stock-based compensation	3,642,000	3,086,000
Deferred financing costs	65,000	1,028,000
Change in fair value of contingent earn-out liability	0	(239,000)
Loss on disposal of property, plant and equipment	3,000	16,000
Provision for allowance for doubtful accounts	315,000	198,000
Provision for excess and obsolete inventory	1,962,000	2,214,000
Excess income tax benefit from stock-based award exercises	(140,000)	(49,000)
Deferred income tax benefit	(1,103,000)	(2,988,000)
Changes in assets and liabilities:
Accounts receivable	(13,049,000)	(15,307,000)
Inventories	(8,729,000)	(4,892,000)
Prepaid expenses and other current assets	(225,000)	(3,108,000)
Other assets	(40,000)	60,000
Accounts payable	(3,882,000)	(2,044,000)
Accrued expenses and other current liabilities	(3,152,000)	(251,000)
Customer advances and deposits	5,063,000	3,116,000
Other liabilities	(608,000)	216,000
Interest payable	(29,000)	1,500,000
Income taxes payable	242,000	1,313,000
Net cash provided by operating activities	7,683,000	10,789,000
Cash flows from investing activities:
Purchases of property, plant and equipment	(2,833,000)	(4,536,000)
Net cash used in investing activities	(2,833,000)	(4,536,000)
Cash flows from financing activities:
Cash dividends paid	(14,581,000)	(13,779,000)
Repurchases of common stock	(4,989,000)	(58,122,000)
Proceeds from exercises of stock options	1,417,000	3,444,000
Proceeds from issuance of employee stock purchase plan shares	707,000	670,000
Excess income tax benefit from stock-based award exercises	140,000	49,000
Fees related to line of credit	0	(75,000)
Payment of contingent consideration related to business acquisition	0	(49,000)
Net cash used in financing activities	(17,306,000)	(67,862,000)
Net decrease in cash and cash equivalents	(12,456,000)	(61,609,000)
Cash and cash equivalents at beginning of period	154,500,000	356,642,000
Cash and cash equivalents at end of period	142,044,000	295,033,000
Cash paid during the period for:
Interest	117,000	3,264,000
Income taxes	8,970,000	11,100,000
Non-cash investing and financing activities:
Cash dividends declared but unpaid (including accrual of dividend equivalents)	5,115,000	4,600,000
Equity-classified stock awards issued	0	139,000
Principal amount of 3.0% convertible senior notes converted into common stock	$ 0	$ 8,501,000