CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Net income	$ 91,944	$ 12,266
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion, and amortization	46,288	39,739
Deferred income taxes	22,758	(52,652)
Share-based compensation	5,799	8,489
Loss on the disposal of property, plant, equipment, and intangibles, net	376	1,217
Other items	(1,595)	3,637
Changes in operating assets and liabilities:
Accounts receivable, net	20,019	2,205
Inventories, net	(2,404)	(44,855)
Other current assets	(6,954)	4,188
Accounts payable	(21,127)	7,414
Accrued SYSTEM 1 Rebate Program and class action settlement	(27,449)	128,770
Accruals and other, net	(14,816)	(27,021)
Net cash provided by operating activities	112,839	83,397
Investing activities:
Purchases of property, plant, equipment, and intangibles, net	(54,238)	(56,390)
Proceeds from the sale of property, plant, equipment, and intangibles	0	1,298
Equity investment in joint venture	0	(16,900)
Investments in businesses, net of cash acquired	(22,269)	(4,000)
Net cash used in investing activities	(76,507)	(75,992)
Financing activities:
Repurchases of common shares	(56,751)	(19,900)
Cash dividends paid to common shareholders	(28,751)	(24,344)
Stock option and other equity transactions, net	3,749	10,813
Tax benefit from stock options exercised	816	2,197
Net cash used in financing activities	(80,937)	(31,234)
Effect of exchange rate changes on cash and cash equivalents	(4,624)	1,146
Decrease in cash and cash equivalents	(49,229)	(22,683)
Cash and cash equivalents at beginning of period	193,016	214,971
Cash and cash equivalents at end of period	$ 143,787	$ 192,288

Name:	us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).