Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net earnings	$ 47,968	$ 63,531	$ 62,576
Adjustments to reconcile net earnings to net cash provided by (used in) operating activities:
Provision for depreciation	9,037	8,637	8,738
Deferred income taxes	5,096	(399)	(33)
Other	628	(790)	682
Changes in operating accounts:
Accounts receivable, net	17,973	1,244	(16,765)
Inventories	(10,284)	(14,557)	3,145
Other current assets	(6,729)	(5,604)	(5,362)
Accounts payable and accrued liabilities	(711)	6,138	7,090
Federal and state income taxes	(4,292)	(432)	2,074
Net cash provided by operating activities	58,686	57,768	62,145
Cash flows from investing activities:
Marketable securities purchased	(40,962)	(45,464)	(78,486)
Marketable securities - maturities and sales	82,521	62,109	81,426
Acquisition of property, plant and equipment	(15,003)	(17,972)	(3,337)
Sale of property, plant and equipment	6	1,365	71
Acquisition of businesses, net of cash acquired	(4,526)
Other	(220)	(1,580)	228
Net cash provided by (used in) investing activities	21,816	(1,542)	(98)
Cash flows from financing activities:
Dividends paid	(56,665)	(55,889)	(38,008)
Other	439	408	243
Net cash used in financing activities	(56,226)	(55,481)	(37,765)
Net increase in cash and cash equivalents	24,276	745	24,282
Cash and cash equivalents at beginning of year	49,719	48,974	24,692
Cash and cash equivalents at end of year	73,995	49,719	48,974
Supplemental disclosures of cash flow information:
Cash paid during the year for: Income taxes	$ 26,686	$ 36,479	$ 30,663

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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).