Segment Information (Summary of Segment Perfomance Measures by Segment) (Detail) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Mar. 31, 2018		Mar. 31, 2017	Mar. 31, 2018		Mar. 31, 2017
Segment Reporting Information [Line Items]
Net sales	$ 185,998	[1]	$ 190,128	$ 542,482	[1]	$ 443,698
Gross profit	27,696	[1]	42,319	101,649	[1]	103,963
(Loss) income before income taxes	(263,037)	[1]	8,512	(261,398)	[1]	14,358
Operating Segments | Human Health
Segment Reporting Information [Line Items]
Net sales	91,926		99,816	301,407		201,686
Gross profit	9,535		25,300	57,080		56,424
(Loss) income before income taxes	(265,486)	[2]	5,007	(258,172)	[2]	13,912
Operating Segments | Pharmaceutical Ingredients
Segment Reporting Information [Line Items]
Net sales	43,201		43,821	113,406		121,253
Gross profit	7,038		7,255	17,259		19,867
(Loss) income before income taxes	2,987		3,036	5,795		7,299
Operating Segments | Performance Chemicals
Segment Reporting Information [Line Items]
Net sales	50,871		46,491	127,669		120,759
Gross profit	11,123		9,764	27,310		27,672
(Loss) income before income taxes	6,699		5,034	14,121		13,599
Unallocated Corporate
Segment Reporting Information [Line Items]
Net sales	0		0	0		0
Gross profit	0		0	0		0
(Loss) income before income taxes	$ (7,237)		$ (4,565)	$ (23,142)		$ (20,452)

[1] (as restated)

[2] Includes goodwill impairment charge of $235,110. See Note 8 Fair Value Measurements for details.