Condensed Consolidated Statements of Operations - USD ($) shares in Millions	3 Months Ended		6 Months Ended
	Jun. 27, 2025	Jun. 28, 2024	Jun. 27, 2025	Jun. 28, 2024
Revenues:
Total revenues	$ 518,800,000	$ 516,100,000	$ 1,037,400,000	$ 993,900,000
Cost of revenues:
Total cost revenues	439,300,000	427,600,000	873,900,000	822,800,000
Gross margin	79,500,000	88,500,000	163,500,000	171,100,000
Operating expenses:
Research and development	7,800,000	7,100,000	15,400,000	14,100,000
Sales and marketing	15,500,000	14,800,000	30,500,000	28,500,000
General and administrative	46,900,000	43,700,000	95,400,000	88,300,000
Impairment of goodwill	151,100,000	0	151,100,000	0
Total operating expenses	221,300,000	65,600,000	292,400,000	130,900,000
Income (loss) from operations	(141,800,000)	22,900,000	(128,900,000)	40,200,000
Interest income	800,000	1,400,000	1,900,000	2,800,000
Interest expense	(10,100,000)	(11,700,000)	(20,000,000.0)	(23,900,000)
Other income (expense), net	(2,200,000)	17,400,000	(1,300,000)	13,500,000
Income (loss) before provision for income taxes	(153,300,000)	30,000,000.0	(148,300,000)	32,600,000
Provision for income taxes	7,200,000	8,500,000	14,600,000	18,400,000
Net income (loss)	(160,500,000)	21,500,000	(162,900,000)	14,200,000
Less: Net income attributable to noncontrolling interests	1,500,000	2,400,000	4,100,000	4,500,000
Net income (loss) attributable to UCT	$ (162,000,000.0)	$ 19,100,000	$ (167,000,000.0)	$ 9,700,000
Net income (loss) per share attributable to UCT common stockholders:
Basic (in dollars per share)	$ (3.58)	$ 0.43	$ (3.70)	$ 0.22
Diluted (in dollars per share)	$ (3.58)	$ 0.42	$ (3.70)	$ 0.21
Shares used in computing net income (loss) per share:
Basic (in shares)	45.2	44.9	45.2	44.7
Diluted (in shares)	45.2	45.4	45.2	45.3
Products
Revenues:
Total revenues	$ 454,900,000	$ 452,700,000	$ 911,900,000	$ 871,200,000
Cost of revenues:
Total cost revenues	393,300,000	383,900,000	783,500,000	738,000,000.0
Services
Revenues:
Total revenues	63,900,000	63,400,000	125,500,000	122,700,000
Cost of revenues:
Total cost revenues	$ 46,000,000.0	$ 43,700,000	$ 90,400,000	$ 84,800,000