The tax effect as of the balance sheet date of the amount of estimated future tax deductions arising from postretirement and post-employment benefits, which can only be deducted for tax purposes when actual costs are incurred, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken.

No definition available.

Income Taxes (Details) - USD ($) $ / shares in Units, $ in Thousands	4 Months Ended	12 Months Ended
	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2016
Current Provision [Abstract]
U.S. - Federal		$ 2,384	$ (2,216)	$ 912
International		52,518	46,112	105,228
State and Local		2,536	961	100
Total Current Provision		57,438	44,857	106,240
Deferred Provision (Benefit) [Abstract]
U.S. - Federal		335	(26,062)	(13,852)
International		(7,630)	2,420	(15,330)
State and Local		(5,454)	530	415
Total Deferred (Benefit) Provision		(12,749)	(23,112)	(28,767)
Total Provision		44,689	21,745	77,473
Foreign and domestic pretax income [Abstract]
International		204,326	219,178	192,910
United States		8,626	(5,247)	(1,794)
Income Before Taxes		$ 212,952	$ 213,931	$ 191,116
Effective income tax rate reconciliation [Abstract]
U.S. Federal Statutory Rate	21.00%	21.00%	30.40%	35.00%
German Tax Litigation Expense		0.00%	0.00%	25.70%
Cost (Benefit) of Higher (Lower) Taxes on Non-U.S. Income		0.90%	(8.40%)	(12.70%)
State Income Taxes, net of U.S. Federal Tax Benefit		(1.30%)	0.40%	0.10%
Deferred Tax (Benefit) from U.S. Tax Reform Rate Change		0.10%	(11.70%)	0.00%
Deferred Tax Benefit from U.K. Statutory Tax Rate Change		0.00%	0.00%	(1.30%)
Tax Credits and Related Benefits		(0.80%)	(1.70%)	(6.20%)
Tax Adjustments and Other		1.10%	1.20%	(0.10%)
Effective Income Tax Rate		21.00%	10.20%	40.50%
Expense recorded with completion of SAB 118 analysis (2019) and Provisional benefit amount recorded related to re-measurement of net deferred tax liability (2018)		$ 200	$ 25,000
Estimated net impact of non-recurring items from Tax Act excluding non-recurring items		21.00%	21.90%
Income Tax Contingency [Line Items]
Recorded tax benefits due to expiration of statute of limitations and favorable resolutions of certain tax matters with tax authorities		$ 300	$ 600
Income Tax Disclosure [Line Items]
U.S. Federal Statutory Rate	21.00%	21.00%	30.40%	35.00%
Repatriation tax rate on foreign earnings held in cash equivalents and certain net assets		15.50%
Repatriation tax rate on foreign earnings held in other assets		8.00%
Provisional tax expense related to mandatory deemed repatriation tax on foreign earnings		$ 14,200
Accounting for uncertainty in income taxes [Abstract]
Accruals for interest and penalties	$ 600	700	$ 600
Net interest expense on reserves for unrecognized and recognized tax benefits		300	200
Total amount of unrecognized tax benefits that, if recognized, would reduce the Company's income tax provision	6,800	7,700	6,800
Reconciliation of unrecognized tax benefits [Roll Forward]
Tax benefit related to Foreign Derived Intangible Income benefit		6,833	6,124
Additions for Current Year Tax Positions		1,473	1,372
Additions for Prior Year Tax Positions		414	69
Reductions for Prior Year Tax Positions		(578)	(38)
Foreign Translation Adjustment		(42)
Foreign Translation Adjustment			45
Payments and Settlements		(136)	(124)
Reductions for Lapse of Statute of Limitations		(305)	(615)
Balance, end of period	6,833	7,659	6,833	$ 6,124
Income Tax Examination [Line Items]
Income tax charge related to unfavorable tax settlement		0	0	$ 49,029
Significant components of deferred tax assets and liabilities [Abstract]
Net Operating Losses	8,976	14,491	8,976
Reserve for Sales Returns and Doubtful Accounts	2,506	2,923	2,506
Accrued Employee Compensation	20,096	17,528	20,096
Foreign and Federal Credits	31,109	34,401	31,109
Other Accrued Expenses	4,632	6,262	4,632
Retirement and Post-Employment Benefits	39,160	40,653	39,160
Total Gross Deferred Tax Assets	106,479	116,258	106,479
Less Valuation Allowance	(8,811)	(21,179)	(8,811)
Total Deferred Tax Assets	97,668	95,079	97,668
Prepaid Expenses and Other Current Assets	(3,203)	(744)	(3,203)
Unremitted Foreign Earnings	(1,985)	(1,985)	(1,985)
Intangible and Fixed Assets	(231,869)	(226,898)	(231,869)
Total Deferred Tax Liabilities	(237,057)	(229,627)	(237,057)
Net Deferred Tax Liabilities	(139,389)	(134,548)	(139,389)
Reported As [Abstract]
Non-current Deferred Tax Assets	4,129	9,227	4,129
Non-current Deferred Tax Liabilities	(143,518)	(143,775)	(143,518)
Net Deferred Tax Liabilities	$ (139,389)	$ (134,548)	$ (139,389)
U.K. [Member]
Income Tax Contingency [Line Items]
Foreign statutory tax rate		57.00%			19.00%
Foreign statutory tax rate in 2020				17.00%	18.00%
Tax benefit from the re-measurement legislation enacted				$ (2,600)
Deferred tax benefits associated with new tax legislation enacted (in dollars per share)				$ 0.04
Germany [Member]
Income Tax Contingency [Line Items]
Foreign statutory tax rate		24.00%
Australia [Member]
Income Tax Contingency [Line Items]
Foreign statutory tax rate		7.00%
Foreign Tax Authority [Member]
Effective income tax rate reconciliation [Abstract]
U.S. Federal Statutory Rate		13.125%
Income Tax Disclosure [Line Items]
U.S. Federal Statutory Rate		13.125%
Estimated taxes upon repatriation		$ 2,000
Reconciliation of unrecognized tax benefits [Roll Forward]
Balance, end of period		1,200
Income Tax Examination [Line Items]
Income tax charge related to unfavorable tax settlement				$ 49,029
Income tax charge related to unfavorable tax settlement (in dollars per share)				$ 0.85
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry forwards		99,000
Net operating loss carry forwards, tax effect		$ 6,000
State and Local Jurisdiction [Member] \| Minimum [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry forwards, expiration period		1 year
State and Local Jurisdiction [Member] \| Maximum [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carry forwards, expiration period		20 years