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SEGMENT AND GEOGRAPHICAL INFORMATION - Concentration Risk (Details)	3 Months Ended		6 Months Ended
	Jul. 04, 2025	Jun. 28, 2024	Jul. 04, 2025	Jun. 28, 2024
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Top Ten Customers
Concentration Risk
Concentration risk (as a percent)	52.50%	52.40%	52.60%	49.80%
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)	44.60%	44.30%	42.40%	43.90%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | New York
Concentration Risk
Concentration risk (as a percent)	18.40%	23.70%	20.00%	25.30%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | Nevada
Concentration Risk
Concentration risk (as a percent)	11.10%	12.40%
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%

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