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SEGMENT AND GEOGRAPHICAL INFORMATION - Concentration Risk (Details)	3 Months Ended
	Apr. 04, 2025	Mar. 29, 2024
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Top Ten Customers
Concentration Risk
Concentration risk (as a percent)	53.80%	49.20%
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 | Customer Concentration Risk | Southern California Edison and Clark County School District | Energy
Concentration Risk
Concentration risk (as a percent)	29.10%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | California
Concentration Risk
Concentration risk (as a percent)	39.80%	43.50%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | New York
Concentration Risk
Concentration risk (as a percent)	21.70%	27.10%
Revenue from Contract with Customer, Segment Benchmark | Customer Concentration Risk | Los Angeles Department of Water and Power | Energy
Concentration Risk
Concentration risk (as a percent)		10.70%

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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