| **Valuation and Qualifying Accounts and Reserves** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
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| **Valuation and Qualifying Accounts [Abstract]**   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Valuation and Qualifying Accounts and Reserves     | Consolidated Financial Statement ScheduleSchedule II - Valuation and Qualifying Accounts and Reserves(in thousands)For the Years Ended July 31,  Balance atBeginning ofPeriod Charged toCosts andExpenses Deductions Balance atEnd ofPeriod2010       Inventory Reserves$1,455 $2,310 $(2,313) $1,452Valuation Allowance on Income Taxes1,588 — — 1,588Trade Receivable Allowances1,877 1,328 (946) 2,2592011       Inventory Reserves1,452 2,389 (2,289) 1,552Valuation Allowance on Income Taxes1,588 — — 1,588Trade Receivable Allowances$2,259 $2,246 $(1,082) $3,4232012       Inventory Reserves1,552 1,914 (1,602) 1,864Valuation Allowance on Income Taxes1,588 — — 1,588Trade Receivable Allowances$3,423 $2,456 $(1,326) $4,553 |

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| - Definition
The entire disclosure for any allowance and reserve accounts (their beginning and ending balances, as well as a reconciliation by type of activity during the period). Alternatively, disclosure of the required information may be within the footnotes to the financial statements or a supplemental schedule to the financial statements.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 09 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690
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