Segment Information (Summary of Segment Perfomance Measures by Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Net sales	$ 185,255	$ 128,018
Gross profit	39,983	30,839
Income (loss) before income taxes	2,138	6,780
Operating Segments \| Human Health
Segment Reporting Information [Line Items]
Net sales	106,015	47,889
Gross profit	24,647	14,205
Income (loss) before income taxes	5,026	3,972
Operating Segments \| Pharmaceutical Ingredients
Segment Reporting Information [Line Items]
Net sales	36,576	40,616
Gross profit	5,840	6,954
Income (loss) before income taxes	2,231	3,067
Operating Segments \| Performance Chemicals
Segment Reporting Information [Line Items]
Net sales	42,664	39,513
Gross profit	9,496	9,680
Income (loss) before income taxes	4,945	4,832
Unallocated Corporate
Segment Reporting Information [Line Items]
Net sales
Gross profit
Income (loss) before income taxes	$ (10,064)	$ (5,091)

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(8))
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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