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SEGMENT AND GEOGRAPHICAL INFORMATION - Concentration Risk (Details) | 3 Months Ended | 9 Months Ended
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Oct. 03, 2025 | Sep. 27, 2024 | Oct. 03, 2025 | Sep. 27, 2024
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Top Ten Customers |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) | 54.80% | 49.10% | 52.30% | 49.50%
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Southern California Edison and Clark County School District |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) | 26.80% |  | 25.80% |
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | California |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) | 46.30% | 42.20% | 43.70% | 43.30%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | New York |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) | 17.30% | 21.00% | 19.00% | 23.70%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | Nevada |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) | 12.90% | 12.60% |  |
Revenue from Contract with Customer, Segment Benchmark | Customer Concentration Risk | Southern California Edison and Clark County School District | Energy |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) | 31.50% | 22.10% | 30.70% |

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