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Accounts Receivable - Customer Credit Concentration (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Jan. 30, 2021 | Jan. 25, 2020 | Jan. 26, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Amount | $ 858,123 | $ 817,245 |
% of Total | 100.00% | 100.00% | 100.00%
Verizon Communications Inc. | Trade Accounts Receivable and Costs and Estimated Earnings [Member] | Customer Concentration Risk [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Amount | $ 389,900 | $ 440,200 |
% of Total | 37.40% | 41.80% |
Lumen Technologies | Trade Accounts Receivable and Costs and Estimated Earnings [Member] | Customer Concentration Risk [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Amount | $ 173,500 | $ 175,800 |
% of Total | 16.60% | 16.70% |
Comcast Corporation | Trade Accounts Receivable and Costs and Estimated Earnings [Member] | Customer Concentration Risk [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Amount | $ 131,700 | $ 114,000 |
% of Total | 12.60% | 10.80% |

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