Changes in Other Comprehensive Loss (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2020	Sep. 30, 2020
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Beginning balance net of tax	$ (109,692)	$ (114,350)
Other comprehensive income (loss) before reclassification	(2,613)	(3,288)
Amounts reclassified from other comprehensive loss	19,397	24,730
Net current period other comprehensive income (loss)	16,784	21,442
Ending balance net of tax	(92,908)	(92,908)
Retirement Obligations
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Beginning balance net of tax	(77,172)	(79,041)
Other comprehensive income (loss) before reclassification	(3,348)	(4,253)
Amounts reclassified from other comprehensive loss	13,419	16,193
Net current period other comprehensive income (loss)	10,071	11,940
Ending balance net of tax	(67,101)	(67,101)
Foreign currency exchange (gain) loss
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Beginning balance net of tax	(31,557)	(34,359)
Other comprehensive income (loss) before reclassification	6,631	9,433
Amounts reclassified from other comprehensive loss	0	0
Net current period other comprehensive income (loss)	6,631	9,433
Ending balance net of tax	(24,926)	(24,926)
Change in Derivatives Qualifying as Hedges
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from other comprehensive loss	7,712	11,012
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	5,978	8,537
Tax expense \| Retirement Obligations
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from other comprehensive loss	(3,753)	(4,529)
Tax expense \| Change in Derivatives Qualifying as Hedges
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from other comprehensive loss	(1,734)	(2,475)
Cost of products sold \| Retirement Obligations
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from other comprehensive loss	17,172	20,722
Cost of products sold \| Change in Derivatives Qualifying as Hedges
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from other comprehensive loss	(90)	(101)
Interest Expense [Member] \| Change in Derivatives Qualifying as Hedges
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from other comprehensive loss	548	886
Foreign currency exchange (gain) loss \| Change in Derivatives Qualifying as Hedges
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amounts reclassified from other comprehensive loss	7,254	10,227
Change in Derivatives Qualifying as Hedges
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Beginning balance net of tax	(963)	(950)
Other comprehensive income (loss) before reclassification	(5,896)	(8,468)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Tax	5,978	8,537
Net current period other comprehensive income (loss)	82	69
Ending balance net of tax	$ (881)	$ (881)

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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