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SEGMENT AND GEOGRAPHICAL INFORMATION - Concentration Risk (Details)	3 Months Ended		9 Months Ended
	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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