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Restructuring and Other Charges, Net - Changes in Employee-Related Restructuring Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2017
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 21,085
Additional Charges (Reversals), Net	4,918
Non-Cash Charges	(3,366)
Additional charges, net	4,918	$ 16,174
Payments	(2,121)
Ending Balance	20,516		$ 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	(146)
Ending Balance	960		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
Frutarom Integration Initiative \| Employee Severance
Restructuring Reserve [Roll Forward]
Beginning Balance	4,038
Additional Charges (Reversals), Net	1,869
Non-Cash Charges	0
Additional charges, net	15,300
Payments	(928)
Ending Balance	4,979		4,038
Frutarom Integration Initiative \| Fixed Asset Write Down [Member]
Restructuring Reserve [Roll Forward]
Beginning Balance	0
Additional Charges (Reversals), Net	3,366
Non-Cash Charges	(3,366)
Payments	0
Ending Balance	0		0
Frutarom Integration Initiative \| Other
Restructuring Reserve [Roll Forward]
Beginning Balance	2,485
Additional Charges (Reversals), Net	(317)
Non-Cash Charges	0
Payments	1
Ending Balance	2,169		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	(1,048)
Ending Balance	11,849		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
Taste
Restructuring Reserve [Roll Forward]
Additional charges, net	4,918	2,553
Scent [Member]
Restructuring Reserve [Roll Forward]
Additional charges, net	0	10,900
Shared IT & Corporate Costs [Member]
Restructuring Reserve [Roll Forward]
Additional charges, net	$ 0	$ 2,721