Nature Of Operations And Significant Accounting Policies (Narrative) (Details)		12 Months Ended
		Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)
Nature Of Operations And Significant Accounting Policies [Line Items]
Number of countries in which entity operates		30
Dividends received on equity method investments	[1]	$ 7,517,000	$ 5,541,000	$ 5,078,000
Payments to Noncontrolling Interests		600,000
Advances to suppliers, current and non-current		129,000,000	150,000,000
Valuation allowance amount related to advances to suppliers		18,000,000	22,000,000
Provision (recoveries) for loss on uncollectible advances to suppliers		(2,300,000)	3,700,000	(900,000)
Advances to suppliers on which interest has been discontinued		6,000,000	8,000,000
Aggregate balance of recoverable value added tax credits		53,000,000	49,000,000
Valuation allowance on recoverable value added tax credits		17,000,000	15,000,000
Interest costs capitalized		0	0	0
Goodwill, Impairment Loss		889,000	0	0
Impairment of property, plant and equipment		14,600,000	0	2,300,000
Foreign currency remeasurement gain (loss)		1,800,000	(200,000)	9,300,000
Foreign currency transaction gain (loss)		$ 4,300,000	100,000	$ 1,300,000
Percentage of revenue earned from processing tobacco owned by customers		5.00%
Reclassification of Tax Effects out of Accumulated Other Comprehensive Income			0
Adoption of FASB Accounting Standards Update 2016-16 eliminating deferred income taxes on unrecognized gains on intra-entity transfers of assets other than inventory (see Note 1)		$ (1,934,000)
Zimbabwe [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Investment in deconsolidated subsidiary		0	0
Net foreign currency translation loss		$ 7,200,000
Minimum [Member] | Buildings [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Estimated useful life		15 years
Minimum [Member] | Processing And Packing Machinery [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Estimated useful life		3 years
Minimum [Member] | Transport Equipment [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Estimated useful life		3 years
Minimum [Member] | Computer Equipment [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Estimated useful life		3 years
Maximum [Member] | Buildings [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Estimated useful life		40 years
Maximum [Member] | Processing And Packing Machinery [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Estimated useful life		11 years
Maximum [Member] | Transport Equipment [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Estimated useful life		10 years
Maximum [Member] | Computer Equipment [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Estimated useful life		12 years
Accounting Standards Update 2015-03 [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Unamortized Debt Issuance Expense			2,000,000
AOCI Attributable to Parent [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Reclassification of Tax Effects out of Accumulated Other Comprehensive Income			(12,373,000)
Retained Earnings [Member]
Nature Of Operations And Significant Accounting Policies [Line Items]
Reclassification of Tax Effects out of Accumulated Other Comprehensive Income			$ 12,373,000
Adoption of FASB Accounting Standards Update 2016-16 eliminating deferred income taxes on unrecognized gains on intra-entity transfers of assets other than inventory (see Note 1)		$ (1,934,000)

[1] In accordance with the applicable accounting guidance, dividends received from unconsolidated affiliates accounted for on the equity method that represent a return on capital (i.e., a return of earnings on a cumulative basis) are presented as operating cash flows in the consolidated statements of cash flows.