Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Line Items]
U.S. federal tax rate					21.00%	35.00%	35.00%
Reversals of liabilities for uncertain tax positions	$ 3,900			$ 9,500	$ 3,900	$ 9,500	$ 7,500
Tax reform, toll charge				100,600
Tax reform, remeasurement	38,600
Repatriation amount	32,800		$ 600
Deferred tax assets realized	52,900				52,900
Valuation allowance	3,800				3,800
Tax reform, benefit recorded					6,700
Valuation allowance	200,280			207,483	200,280	207,483
Operating loss carryforwards	225,152			218,933	225,152	218,933
Deferred tax asset	227,200				227,200
Valuation allowance for net operating loss carryforwards	195,500				195,500
Valuation allowance established against certain other net deferred tax assets	3,000				3,000
Reduction in accrual for interest and penalties	1,100			3,000	1,100	3,000	300
Accrued interest and penalties	3,000			2,800	3,000	2,800	800
Unrecognized tax benefits, including interest	53,900				53,900
Tax benefits credited to Shareholders' equity						100	200
TCJA, provisional income tax expense (benefit), toll charge		$ 8,000				2,000,000
TCJA, remeasurement, income tax expense (benefit)		$ 200
Domestic earnings repatriated	88,800				88,800
Foreign earnings, deferred tax liability	43,800				43,800
Other liabilities [Member]
Income Taxes [Line Items]
Unrecognized tax benefits that would impact effective tax rate	47,300			28,500	47,300	28,500	19,100
Other Current Liabilities [Member]
Income Taxes [Line Items]
Unrecognized tax benefits that would impact effective tax rate	3,600				3,600		9,700
2018 to 2037 [Member]
Income Taxes [Line Items]
Operating loss carryforwards	209,400			212,500	209,400	212,500
Deferred tax assets, operating loss carryforwards, subject to expiration				8,500		8,500
Tax credit carryforwards	17,800			$ 12,500	17,800	$ 12,500
Tax credits established against deferred tax assets	17,800				17,800
Indefinite [Member]
Income Taxes [Line Items]
Operating loss carryforwards	200,900				200,900
Other Liabilities [Member]
Income Taxes [Line Items]
Accrued interest and penalties	1,300				1,300		$ 300
State and Local Jurisdiction [Member]
Income Taxes [Line Items]
Valuation allowance	3,000				3,000
Frutarom Industries Ltd. [Member]
Income Taxes [Line Items]
Foreign earnings, deferred tax liability	$ 45,000				$ 45,000