Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands	3 Months Ended
Jul. 31, 2011	Jul. 31, 2010
Cash flows from operations:
Net earnings	$ 39,391	$ 37,286
Adjustments to reconcile net earnings to net cash provided by operations:
Depreciation and amortization	22,895	19,563
Other amortization	385	292
Stock based compensation	477	810
Loss on sale and disposal of property and equipment	386	112
Deferred income taxes	9,634	(1,056)
Excess tax benefits related to stock option exercises	(268)	(154)
Changes in assets and liabilities:
Receivables	(2,183)	(922)
Inventories	(2,243)	1,699
Prepaid expenses	(1,259)	(1,126)
Accounts payable	30,133	18,731
Accrued expenses	15,189	6,735
Income taxes	50,318	22,764
Other, net	4	(1,037)
Net cash provided by operations	162,859	103,697
Cash flows from investing:
Purchase of property and equipment	(47,514)	(39,352)
Payments for acquisition of stores, net of cash acquired	(31,115)	(295)
Proceeds from sale of property and equipment	322	287
Net cash used in investing activities	(78,307)	(39,360)
Cash flows from financing:
Payments of long-term debt	(384)	(13,959)
Net borrowing of short-term debt	(600)
Proceeds from exercise of stock options	1,316	988
Payments of cash dividends	(5,707)	(5,097)
Excess tax benefits related to stock option exercises	268	154
Net cash used in financing activities	(5,107)	(17,914)
Net increase in cash and cash equivalents	79,445	46,423
Cash and cash equivalents at beginning of the period	59,572	151,676
Cash and cash equivalents at end of the period	139,017	198,099
SUPPLEMENTAL DISCLOSURES OF CASH FLOWS INFORMATION
Interest, net of amount capitalized	126	1,847
Income taxes	$ (36,035)	$ 283

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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).