SEGMENT AND GEOGRAPHIC INFORMATION - Operating Segments Revenue and Operating Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
SEGMENT INFORMATION
Revenue	$ 120,879	$ 119,876
Other segment operating expenses	1,177	961
Operating loss	(16,330)	(15,507)
Unallocated corporate expenses	15,730	16,110
Depreciation and amortization of intangible assets	13,791	14,179
Startup costs	731	559
Restructuring costs	186	224
Interest expense, net	(13,463)	(13,838)
Other expense	(223)	(463)
Loss before income taxes	(30,016)	(29,808)
Stock based compensation expense	1,382	1,770
Depreciation and amortization	13,791	14,179
Capital expenditures	5,180	4,459
Operating Segments
SEGMENT INFORMATION
Revenue	120,879	119,876
Operating loss	15,285	16,526
Unallocated Corporate
SEGMENT INFORMATION
Depreciation and amortization	195	158
Service
SEGMENT INFORMATION
Revenue	59,721	53,557
Cost of revenue (excluding depreciation and amortization of intangible assets)	43,739	39,244
Product
SEGMENT INFORMATION
Revenue	61,158	66,319
Cost of revenue (excluding depreciation and amortization of intangible assets)	52,330	55,594
Discovery and Safety Assessment Segment
SEGMENT INFORMATION
Capital expenditures	960	376
Discovery and Safety Assessment Segment | Operating Segments
SEGMENT INFORMATION
Revenue	47,955	42,822
Cost of revenue (excluding depreciation and amortization of intangible assets)	34,602	30,812
Selling, general and administrative expenses	4,809	4,589
Other segment operating expenses	318	333
Operating loss	8,226	7,088
Depreciation and amortization	4,346	4,583
Discovery and Safety Assessment Segment | Service | Operating Segments
SEGMENT INFORMATION
Revenue	46,430	41,843
Discovery and Safety Assessment Segment | Product | Operating Segments
SEGMENT INFORMATION
Revenue	1,525	979
Research Models And Services Segment
SEGMENT INFORMATION
Capital expenditures	4,220	4,083
Research Models And Services Segment | Operating Segments
SEGMENT INFORMATION
Revenue	72,924	77,054
Cost of revenue (excluding depreciation and amortization of intangible assets)	61,467	64,026
Selling, general and administrative expenses	4,398	3,590
Other segment operating expenses	0	0
Operating loss	7,059	9,438
Depreciation and amortization	9,250	9,438
Research Models And Services Segment | Service | Operating Segments
SEGMENT INFORMATION
Revenue	13,291	11,714
Research Models And Services Segment | Product | Operating Segments
SEGMENT INFORMATION
Revenue	$ 59,633	$ 65,340