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SEGMENT AND GEOGRAPHICAL INFORMATION - Concentration Risk (Details) | 3 Months Ended | 6 Months Ended
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Jul. 03, 2026 | Jul. 04, 2025 | Jul. 03, 2026 | Jul. 04, 2025
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Top Ten Customers |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) | 51.70% | 52.50% | 47.10% | 52.60%
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Southern California Edison and Clark County School District |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) |  | 26.30% |  | 25.30%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | California |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) | 43.70% | 44.60% | 44.60% | 42.40%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | New York |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) | 15.80% | 18.40% | 17.30% | 20.00%
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) |  | 31.10% |  | 30.20%
Revenue from Contract with Customer, Segment Benchmark | Customer Concentration Risk | Southern California Edison | Energy |  |  |  |
Concentration Risk |  |  |  |
Concentration risk (as a percent) | 11.20% |  | 11.30% |

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