Segment and Geographic Reporting - Schedule of Financial Information by Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	$ 4,707,688	$ 5,160,100	$ 3,316,616
Operating income (loss)	96,121	(37,120)	414,294
Interest expense	(288,475)	(286,872)	(121,254)
Other income (expense), net	44,707	(31,566)	(11,233)
Income taxes	(11,117)	96,100	(47,048)
Net loss	(158,764)	(259,458)	234,759
Net earnings (loss) attributable to Coherent Corp.	(156,154)	(259,458)	234,759
Depreciation and amortization	559,761	681,687	286,779
Expenditures for property, plant & equipment	346,816	436,060	314,332
Segment assets	14,488,634	13,711,133	7,844,846
Goodwill	4,464,329	4,512,700	1,285,759
Networking
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	2,295,729	2,340,930	2,197,249
Goodwill	1,036,592	1,036,204	1,013,277
Materials
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	1,016,573	1,349,758	1,119,367
Goodwill	245,983	247,695	272,482
Lasers
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	1,395,386	1,469,412	0
Goodwill	3,181,754	3,228,801	0
Operating Segments | Networking
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	2,295,729	2,340,930	2,197,249
Operating income (loss)	178,789	222,365	231,563
Interest expense	0	0	0
Other income (expense), net	0	0	0
Income taxes	0	0	0
Net loss	0
Net earnings (loss) attributable to Coherent Corp.	0	0	0
Depreciation and amortization	161,499	172,339	172,092
Expenditures for property, plant & equipment	90,950	98,192	89,616
Segment assets	3,543,981	3,316,555	4,897,252
Goodwill	1,036,592	1,036,204	1,013,277
Operating Segments | Materials
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	1,016,573	1,349,758	1,119,367
Operating income (loss)	62,876	159,581	218,601
Interest expense	0	0	0
Other income (expense), net	0	0	0
Income taxes	0	0	0
Net loss	0
Net earnings (loss) attributable to Coherent Corp.	0	0	0
Depreciation and amortization	108,979	143,243	114,687
Expenditures for property, plant & equipment	224,482	274,434	224,716
Segment assets	3,502,642	2,561,156	2,947,594
Goodwill	245,983	247,695	272,482
Operating Segments | Lasers
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	1,395,386	1,469,412	0
Operating income (loss)	(145,544)	(419,066)	0
Interest expense	0	0	0
Other income (expense), net	0	0	0
Income taxes	0	0	0
Net loss	0
Net earnings (loss) attributable to Coherent Corp.	0	0	0
Depreciation and amortization	289,283	366,105	0
Expenditures for property, plant & equipment	31,384	63,434	0
Segment assets	7,442,011	7,833,422	0
Goodwill	3,181,754	3,228,801	0
Inter-segment revenues
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	(508,602)	(433,817)	(366,240)
Inter-segment revenues | Networking
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	45,767	70,120	93,660
Inter-segment revenues | Materials
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	457,623	362,179	272,580
Inter-segment revenues | Lasers
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	5,212	1,517	0
Unallocated & Other
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenues	0	0	0
Operating income (loss)	0	0	(35,870)
Interest expense	0	0	0
Other income (expense), net	0	0	0
Income taxes	0	0	0
Net loss	0
Net earnings (loss) attributable to Coherent Corp.	0	0	0
Depreciation and amortization	0	0	0
Expenditures for property, plant & equipment	0	0	0
Segment assets	0	0	0
Goodwill	$ 0	$ 0	$ 0