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Restructuring and Other Charges, Net - Changes in Employee-Related Restructuring Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2017
Restructuring Reserve [Roll Forward]
Beginning Balance			$ 21,085
Additional Charges (Reversals), Net			6,802
Non-Cash Charges			(3,794)
Additional charges, net	$ 1,884	$ 2,525	6,802	$ 18,699
Payments			(6,345)
Ending Balance	17,748		17,748		$ 21,085
2017 Productivity Program
Restructuring Reserve [Roll Forward]
Additional charges, net						$ 24,500
2017 Productivity Program \| Employee Severance
Restructuring Reserve [Roll Forward]
Beginning Balance			1,106
Additional Charges (Reversals), Net			0
Non-Cash Charges			0
Payments			(217)
Ending Balance	889		889		1,106
2017 Productivity Program \| Other
Restructuring Reserve [Roll Forward]
Beginning Balance			88
Additional Charges (Reversals), Net			0
Non-Cash Charges			0
Payments			0
Ending Balance	88		88		88
Frutarom Integration Initiative \| Employee Severance
Restructuring Reserve [Roll Forward]
Beginning Balance			4,038
Additional Charges (Reversals), Net			1,737
Non-Cash Charges			0
Additional charges, net			17,200
Payments			(2,390)
Ending Balance	3,385		3,385		4,038
Frutarom Integration Initiative \| Fixed Asset Write Down [Member]
Restructuring Reserve [Roll Forward]
Beginning Balance			0
Additional Charges (Reversals), Net			3,766
Non-Cash Charges			(3,766)
Payments			0
Ending Balance	0		0		0
Frutarom Integration Initiative \| Other
Restructuring Reserve [Roll Forward]
Beginning Balance			2,485
Additional Charges (Reversals), Net			1,299
Non-Cash Charges			(28)
Payments			(325)
Ending Balance	3,431		3,431		2,485
2019 Severance Initiatives \| Employee Severance
Restructuring Reserve [Roll Forward]
Beginning Balance			12,897
Additional Charges (Reversals), Net			0
Non-Cash Charges			0
Additional charges, net					21,300
Payments			(3,413)
Ending Balance	9,484		9,484		12,897
2019 Severance Initiatives \| Other
Restructuring Reserve [Roll Forward]
Beginning Balance			471
Additional Charges (Reversals), Net			0
Non-Cash Charges			0
Payments			0
Ending Balance	471		471		$ 471
Taste
Restructuring Reserve [Roll Forward]
Additional charges, net	1,884	2,525	6,802	5,078
Scent [Member]
Restructuring Reserve [Roll Forward]
Additional charges, net	0	0	0	10,900
Shared IT & Corporate Costs [Member]
Restructuring Reserve [Roll Forward]
Additional charges, net	$ 0	$ 0	$ 0	$ 2,721