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Concentration of Credit Risk (Tables) | 9 Months Ended
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Apr. 25, 2015
Risks and Uncertainties [Abstract] |
Schedule that Represents A Significant Portion of the Company’s Customer Base and Each Over 10% of Total Revenue | Customers whose revenues exceeded 10% of total revenue during the three or nine months ended April 25, 2015 or April 26, 2014 were as follows:
| For the Three Months Ended |  | For the Nine Months Ended
| April 25, 2015 |  | April 26, 2014 |  | April 25, 2015 |  | April 26, 2014
AT&T Inc. | 21.3% |  | 20.8% |  | 21.5% |  | 18.9%
CenturyLink, Inc. | 13.9% |  | 12.8% |  | 13.7% |  | 14.3%
Comcast Corporation | 13.3% |  | 12.1% |  | 13.0% |  | 11.5%
Schedule of Customers Representing 10% or More of Combined Amounts of Trade Accounts Receivable and Costs and Estimated Earnings in Excess of Billings with the Following Outstanding Balances and Related Percentages of the Company’s Total Outstanding Balances | Customers representing 10% or more of combined amounts of trade accounts receivable and costs and estimated earnings in excess of billings, net ("CIEB, net") as of April 25, 2015 or July 26, 2014 had the following outstanding balances and the related percentage of the Company’s total outstanding balances:
| April 25, 2015 |  | July 26, 2014
| Amount |  | % of Total |  | Amount |  | % of Total
|  |  | (Dollars in millions) |  |
AT&T Inc. | $ | 103.5 |  |  | 20.7 | % |  | $ | 87.6 |  |  | 17.9 | %
CenturyLink, Inc. | $ | 56.2 |  |  | 11.2 | % |  | $ | 48.2 |  |  | 9.8 | %
Comcast Corporation | $ | 55.5 |  |  | 11.1 | % |  | $ | 48.9 |  |  | 9.9 | %

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- Definition Tabular disclosure of the nature of a concentration, a benchmark to which it is compared, and the percentage that the risk is to the benchmark. + References No definition available. + Details
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- Definition Tabular disclosure of the nature of a concentration, a benchmark to which it is compared, and the percentage that the risk is to the benchmark. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6327-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13531-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13537-108611 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6442-108592 + Details
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