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Restructuring and Other Charges, Net - Changes in Employee-Related Restructuring Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restructuring Reserve [Roll Forward]
Additional charges (reversals), net	$ 3,249	$ 0	$ 14,183	$ 0
Fragrance Ingredients Rationalization [Member]
Restructuring Reserve [Roll Forward]
Beginning Balance			3,277
Additional charges (reversals), net			14,183
Non-cash charges			(950)
Payments			(10,267)
Ending Balance	6,243		6,243
Fragrance Ingredients Rationalization [Member] \| Employee-Related Costs
Restructuring Reserve [Roll Forward]
Beginning Balance			3,277
Additional charges (reversals), net			13,233
Non-cash charges			0
Payments			(10,267)
Ending Balance	6,243		6,243
Fragrance Ingredients Rationalization [Member] \| Other
Restructuring Reserve [Roll Forward]
Beginning Balance			0
Additional charges (reversals), net			950
Non-cash charges			(950)
Payments			0
Ending Balance	$ 0		$ 0