Segment Information (Summary of Segment Perfomance Measures by Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Net sales	$ 164,405	$ 185,255
Gross profit	25,480	39,983
(Loss) income before income taxes	(19,095)	2,138
Human Health
Segment Reporting Information [Line Items]
Net sales	80,846	106,015
Pharmaceutical Ingredients
Segment Reporting Information [Line Items]
Net sales	38,848	36,576
Performance Chemicals
Segment Reporting Information [Line Items]
Net sales	44,711	42,664
Operating Segments \| Human Health
Segment Reporting Information [Line Items]
Net sales	80,846	106,015
Gross profit	8,476	24,647
(Loss) income before income taxes	(13,047)	5,026
Operating Segments \| Pharmaceutical Ingredients
Segment Reporting Information [Line Items]
Net sales	38,848	36,576
Gross profit	6,894	5,840
(Loss) income before income taxes	3,398	2,231
Operating Segments \| Performance Chemicals
Segment Reporting Information [Line Items]
Net sales	44,711	42,664
Gross profit	10,110	9,496
(Loss) income before income taxes	5,928	4,945
Unallocated Corporate
Segment Reporting Information [Line Items]
Net sales	0	0
Gross profit	0	0
(Loss) income before income taxes	$ (15,374)	$ (10,064)

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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