Business Segments (Assets by Segment) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting, Asset Reconciling Item [Line Items]
Goodwill	$ 578,583	$ 620,098	$ 615,252
Indefinite-lived intangible assets	2,273,191	2,490,303
Finite-lived intangible assets	234,019	290,613
Intangible assets, net (excluding goodwill)	2,507,210	2,780,916
Intangible assets, net (including goodwill)	3,085,793	3,401,014
North American OTC Healthcare
Segment Reporting, Asset Reconciling Item [Line Items]
Goodwill	547,393	580,934	576,453
Indefinite-lived intangible assets	2,195,617	2,375,736
Finite-lived intangible assets	228,743	265,356
Intangible assets, net (excluding goodwill)	2,424,360	2,641,092
Intangible assets, net (including goodwill)	2,971,753	3,222,026
International OTC Healthcare
Segment Reporting, Asset Reconciling Item [Line Items]
Goodwill	31,190	32,919	32,554
Indefinite-lived intangible assets	77,574	84,006
Finite-lived intangible assets	5,276	6,068
Intangible assets, net (excluding goodwill)	82,850	90,074
Intangible assets, net (including goodwill)	114,040	122,993
Household Cleaning
Segment Reporting, Asset Reconciling Item [Line Items]
Goodwill	0	6,245	6,245
Indefinite-lived intangible assets	0	30,561
Finite-lived intangible assets	0	19,189
Intangible assets, net (excluding goodwill)	0	49,750
Intangible assets, net (including goodwill)	0	55,995
Finite-Lived Tradenames and Customer Relationships
Segment Reporting, Asset Reconciling Item [Line Items]
Finite-lived intangible assets	234,019
Indefinite- Lived Tradenames
Segment Reporting, Asset Reconciling Item [Line Items]
Indefinite-lived intangible assets	$ 2,273,191	$ 2,490,303	$ 2,589,155

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