Fair Value Measurements - Changes in goodwill (Detail) $ in Thousands	6 Months Ended
	Dec. 31, 2016 USD ($)
Goodwill [Roll Forward]
Balance as of June 30, 2016	$ 67,871
Balance as of December 31, 2016	241,402
Nonrecurring basis | Level 3 inputs | Operating Segments
Goodwill [Roll Forward]
Balance as of June 30, 2016	67,871
Citron and Lucid product acquisition	173,583
Changes in foreign currency exchange rates	(52)
Balance as of December 31, 2016	241,402
Nonrecurring basis | Level 3 inputs | Operating Segments | Human Health
Goodwill [Roll Forward]
Balance as of June 30, 2016	66,039
Citron and Lucid product acquisition	173,583
Balance as of December 31, 2016	239,622
Nonrecurring basis | Level 3 inputs | Operating Segments | Pharmaceutical Ingredients
Goodwill [Roll Forward]
Balance as of June 30, 2016	1,651
Changes in foreign currency exchange rates	(42)
Balance as of December 31, 2016	1,609
Nonrecurring basis | Level 3 inputs | Operating Segments | Performance Chemicals
Goodwill [Roll Forward]
Balance as of June 30, 2016	181
Changes in foreign currency exchange rates	(10)
Balance as of December 31, 2016	$ 171