CONSOLIDATED STATEMENTS OF Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net earnings	$ 8,101	$ 10,011
Adjustments to reconcile net earnings to net cash used in operating activities:
Depreciation and amortization	4,578	4,714
Deferred income taxes	(415)	(230)
Amortization of marketable security premiums	456	593
Changes in operating assets and liabilities:
Accounts receivable	5,858	4,783
Other receivables	(2,729)	(1,297)
Inventories	(12,845)	(9,926)
Prepaid expenses and other assets	4,052	1,758
Accounts payable and accrued liabilities	(501)	(2,384)
Income taxes payable	2,761	3,546
Postretirement health care benefits	(233)	12
Deferred compensation and other liabilities	584	282
Net cash from operating activities	9,667	11,862
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(7,722)	(4,845)
Purchases of trading securities	(3,258)	(2,584)
Sales of trading securities	239	435
Purchase of available for sale securities	(34,061)	(27,227)
Sale and maturity of available for sale securities	11,670	1,759
Net cash used in investing activities	(33,132)	(32,462)
CASH FLOWS FROM FINANCING ACTIVITIES:
Shares purchased and retired	(12,498)	(9,985)
Dividends paid in cash	(11,282)	(11,128)
Proceeds from bank loans	641	324
Repayment of bank loans	(661)	(570)
Net cash used in financing activities	(23,800)	(21,359)
Effect of exchange rate changes on cash	829	1,376
Decrease in cash and cash equivalents	(46,436)	(40,583)
Cash, cash equivalents, and restricted cash at beginning of year	96,720	119,527
Cash, cash equivalents, and restricted cash at end of quarter	50,284	78,944
Supplemental cash flow information:
Income taxes paid/(received), net	(206)	784
Interest paid	24	14
Stock dividend issued	$ 60,538	$ 69,739