Business Segments (Information on Operating and Reportable Segments) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information, Profit (Loss):
Net sales	$ 167,004	$ 161,323	$ 309,105	$ 307,243
Other revenues	1,438	532	2,308	1,609
Total revenues	168,442	161,855	311,413	308,852
Cost of sales	73,723	71,310	133,211	134,703
Gross profit	94,719	90,545	178,202	174,149
Advertising and promotion	26,044	23,508	45,184	43,833
Contribution margin	68,675	67,037	133,018	130,316
Other operating expenses	14,913	15,881	29,815	35,327
Operating income	53,762	51,156	103,203	94,989
Other expense	16,439	19,660	32,344	39,508
Income before income taxes	37,323	31,496	70,859	55,481
Provision for income taxes	4,531	12,252	17,375	21,582
Net income	32,792	19,244	53,484	33,899
OTC Healthcare
Segment Reporting Information, Profit (Loss):
Net sales	142,454	137,771	265,222	263,775
Other revenues	155	164	312	345
Total revenues	142,609	137,935	265,534	264,120
Cost of sales	55,325	53,469	100,336	100,868
Gross profit	87,284	84,466	165,198	163,252
Advertising and promotion	25,313	22,046	43,545	39,899
Contribution margin	61,971	62,420	121,653	123,353
Household Cleaning
Segment Reporting Information, Profit (Loss):
Net sales	24,550	23,552	43,883	43,468
Other revenues	1,283	368	1,996	1,264
Total revenues	25,833	23,920	45,879	44,732
Cost of sales	18,398	17,841	32,875	33,835
Gross profit	7,435	6,079	13,004	10,897
Advertising and promotion	731	1,462	1,639	3,934
Contribution margin	$ 6,704	$ 4,617	$ 11,365	$ 6,963
Geographic Concentration Risk | Sales | United States
Geographic Areas, Revenues from External Customers [Abstract]
Concentration risk, percentage	86.90%	89.30%	87.80%	90.30%
Geographic Concentration Risk | Sales | Canada
Geographic Areas, Revenues from External Customers [Abstract]
Concentration risk, percentage	7.20%	8.10%	7.60%	7.30%