Segment Information (Summary of Segment Perfomance Measures by Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Net sales	$ 128,018	$ 133,500
Gross profit	30,839	34,581
Income (loss) before income taxes	6,780	14,983
Operating Segments \| Human Health
Segment Reporting Information [Line Items]
Net sales	47,889	57,481
Gross profit	14,205	20,309
Income (loss) before income taxes	3,972	10,503
Operating Segments \| Pharmaceutical Ingredients
Segment Reporting Information [Line Items]
Net sales	40,616	38,360
Gross profit	6,954	6,114
Income (loss) before income taxes	3,067	2,099
Operating Segments \| Performance Chemicals
Segment Reporting Information [Line Items]
Net sales	39,513	37,659
Gross profit	9,680	8,158
Income (loss) before income taxes	4,832	3,544
Unallocated Corporate
Segment Reporting Information [Line Items]
Net sales
Gross profit
Income (loss) before income taxes	$ (5,091)	$ (1,163)

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.

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

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