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SEGMENT AND GEOGRAPHICAL INFORMATION - Concentration Risk (Details)	3 Months Ended
	Apr. 03, 2026	Apr. 04, 2025
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Top Ten Customers
Concentration Risk
Concentration risk (as a percent)	49.10%	53.80%
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Southern California Edison and Clark County School District
Concentration Risk
Concentration risk (as a percent)		24.10%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | California
Concentration Risk
Concentration risk (as a percent)	46.00%	39.80%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | New York
Concentration Risk
Concentration risk (as a percent)	19.40%	21.70%
Revenue from Contract with Customer, Segment Benchmark | Customer Concentration Risk | Southern California Edison and New York Power Authority | Energy
Concentration Risk
Concentration risk (as a percent)	22.40%
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)		29.10%

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