CONSOLIDATED STATEMENTS OF Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net earnings	$ 10,011	$ 9,856
Adjustments to reconcile net earnings to net cash used in operating activities:
Depreciation and amortization	4,714	5,152
Deferred income taxes	(230)	671
Amortization of marketable security premiums	593	748
Changes in operating assets and liabilities:
Accounts receivable	4,783	10,627
Other receivables	(1,297)	109
Inventories	(9,926)	(6,706)
Prepaid expenses and other assets	1,758	1,353
Accounts payable and accrued liabilities	(2,384)	(4,406)
Income taxes payable	3,546	(2,619)
Postretirement health care benefits	12	(312)
Deferred compensation and other liabilities	282	507
Net cash from operating activities	11,862	14,980
CASH FLOWS FROM INVESTING ACTIVITIES:
Restricted cash	4	1
Capital expenditures	(4,845)	(8,376)
Purchases of trading securities	(2,584)	(2,485)
Sales of trading securities	435	613
Purchase of available for sale securities	(27,227)	(23,348)
Sale and maturity of available for sale securities	1,759	4,871
Net cash used in investing activities	(32,458)	(28,724)
CASH FLOWS FROM FINANCING ACTIVITIES:
Shares purchased and retired	(9,985)	(6,576)
Dividends paid in cash	(11,128)	(10,943)
Proceeds from bank loans	324	809
Repayment of bank loans	(570)	(612)
Net cash used in financing activities	(21,359)	(17,322)
Effect of exchange rate changes on cash	1,365	(22)
Decrease in cash and cash equivalents	(40,590)	(31,088)
Cash and cash equivalents at beginning of year	119,145	126,145
Cash and cash equivalents at end of year	78,555	95,057
Supplemental cash flow information:
Income taxes paid	784	6,352
Interest paid	14	1
Stock dividend issued	$ 69,739	$ 61,671