Condensed Consolidated Statements of Cash Flows - USD ($)	6 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Cash flows from operating activities:
Net (loss) income	$ (81,635,000)	$ 9,883,000
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
Depreciation and amortization of property, plant and equipment	5,009,000	5,372,000
Amortization of intangible assets with finite lives	10,361,000	10,435,000
Amortization of stock-based compensation	1,986,000	2,117,000
Amortization of deferred financing costs	368,000	369,000
Changes in other liabilities	(3,756,000)	(2,067,000)
Loss on disposal of property, plant and equipment	29,000	17,000
Provision for (benefit from) allowance for doubtful accounts	204,000	(626,000)
Provision for excess and obsolete inventory	2,444,000	932,000
Deferred income tax (benefit) expense	(287,000)	2,912,000
Other	(225,000)	(32,000)
Changes in assets and liabilities, net of effects of business acquisitions:
Accounts receivable	(23,736,000)	(220,000)
Inventories	(1,772,000)	98,000
Prepaid expenses and other current assets	2,124,000	(2,049,000)
Other assets	(115,000)	(197,000)
Accounts payable	14,481,000	2,270,000
Accrued expenses and other current liabilities	(6,734,000)	3,418,000
Contract liabilities	15,210,000	2,119,000
Other liabilities, non-current	3,687,000	32,000
Interest payable	102,000	(245,000)
Income taxes payable	(1,117,000)	(3,271,000)
Net cash (used in) provided by operating activities (See Note (2))	(63,372,000)	31,267,000
Cash flows from investing activities:
Payment for acquisition of CGC, net of cash acquired	(750,000)	(11,165,000)
Purchases of property, plant and equipment	(3,686,000)	(2,508,000)
Net cash used in investing activities	(4,436,000)	(13,673,000)
Cash flows from financing activities:
Net borrowings (payments) of long-term debt under Credit Facility	58,500,000
Net borrowings (payments) of long-term debt under Credit Facility		(7,000,000)
Remittance of employees' statutory tax withholding for stock awards	(2,740,000)	(5,246,000)
Cash dividends paid	(5,237,000)	(5,120,000)
Repayment of principal amounts under finance lease liabilities	(28,000)	(311,000)
Proceeds from issuance of employee stock purchase plan shares	369,000	510,000
Proceeds from exercises of stock options	0	468,000
Net cash provided by (used in) financing activities	50,864,000	(16,699,000)
Net (decrease) increase in cash and cash equivalents	(16,944,000)	895,000
Cash and cash equivalents at beginning of period	47,878,000	45,576,000
Cash and cash equivalents at end of period	30,934,000	46,471,000
Supplemental cash flow disclosures:
Interest paid during the year	3,208,000	3,202,000
Income taxes paid during the year	(991,000)	2,624,000
Non-cash investing and financing activities:
Reclass of finance lease right-of-use assets to property, plant and equipment	0	698,000
Cash dividends declared but unpaid (including accrual of dividend equivalents)	2,686,000	2,545,000
Accrued additions to property, plant and equipment	1,132,000	787,000
Issuance of restricted stock	4,000	0
Common stock issued for acquisitions	0	11,575,000
Accruals related to acquisitions	$ 0	$ 750,000