Segment Information (Schedule of Segment Perfomance Measures by Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended															12 Months Ended
	Jun. 30, 2018	[1],[2]	Mar. 31, 2018		Dec. 31, 2017	Sep. 30, 2017	[4]	Jun. 30, 2017	[5],[6]	Mar. 31, 2017	[6],[7]	Dec. 31, 2016	[6]	Sep. 30, 2016	[8]	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting Information [Line Items]
Net sales	$ 168,877		$ 185,998	[2],[3]	$ 171,229	$ 185,255		$ 194,620		$ 190,128		$ 125,552		$ 128,018		$ 711,359	$ 638,318	$ 558,524
Gross profit	$ 9,914		27,696	[2],[3]	$ 33,970	$ 39,983		$ 36,829		$ 42,319		$ 30,805		$ 30,839		111,563	140,792	142,785
Income (loss) before income taxes			$ (267,985)													(292,822)	17,361	53,854
Operating Segments | Human Health
Segment Reporting Information [Line Items]
Net sales																374,514	315,395	228,035
Gross profit																48,787	78,109	77,880
Income (loss) before income taxes																(289,219)	15,434	36,362
Operating Segments | Pharmaceutical Ingredients
Segment Reporting Information [Line Items]
Net sales																158,854	157,445	161,011
Gross profit																24,633	25,474	28,752
Income (loss) before income taxes																7,654	9,322	11,856
Operating Segments | Performance Chemicals
Segment Reporting Information [Line Items]
Net sales																177,991	165,478	169,478
Gross profit																38,143	37,209	36,153
Income (loss) before income taxes																18,935	18,829	17,799
Unallocated Corporate
Segment Reporting Information [Line Items]
Net sales																0	0	0
Gross profit																0	0	0
Income (loss) before income taxes																$ (30,192)	$ (26,224)	$ (12,163)

[1] Includes pretax item of $920 environmental remediation charge in connection with Arsynco and $76,500 valuation allowance on deferred tax assets.

[2] The Company (i) has recorded in its 2018 year-end financial statements a $76,500 valuation allowance against its U.S. net deferred tax assets for the year ended June 30, 2018, (ii) has determined that $71,350 of this non-cash charge should have been recognized in the third quarter of fiscal 2018, rather than in the fourth quarter of fiscal 2018, and (iii) accordingly will amend its most recently filed Quarterly Report on Form 10-Q to restate its third quarter and nine month consolidated financial statements to reflect $71,350 of the charge as a third quarter event. A reconciliation of the amounts previously reported for the quarter ended March 31, 2018 with the amounts to be set forth in such restated financial statements, is set forth below: For the quarter ended March 31, 2018 As reported Adjustment As restated Income (loss) before income taxes $ (196,635 ) $ (71,350 ) $ (267,985 ) Net income (loss) per diluted share $ (5.57 ) $ (2.02 ) $ (7.59 )

[3] Includes impairment charges on goodwill and intangibles of $256,266 related to the Rising reporting unit.

[4] Includes pretax item of $902 environmental remediation charge in connection with Arsynco.

[5] Includes pretax item of $3,139 representing immaterial correction of an error associated with certain accrued expenses.

[6] Results for the last nine days of the quarter ended December 31, 2016 and for the subsequent two quarters reflect the acquisition of certain generic products and related assets from Citron and Lucid on December 21, 2016.

[7] Includes pretax item of $733 environmental remediation charge in connection with Arsynco.

[8] Includes pretax item of $170 environmental remediation charge in connection with Arsynco.