Consolidated Statements Of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net earnings	$ 40,496,000	$ 26,477,000	$ 41,252,000
Adjustments to reconcile net earnings to net cash provided by operating activities:
Intangibles amortization	5,173,000	11,991,000	667,000
Provision for depreciation	10,427,000	9,828,000	8,277,000
Deferred income tax provision (benefit)	(998,000)	(1,005,000)	239,000
Impairment of finite lived intangible assets		2,063,000
Change in contingent consideration liability			(3,000,000)
Goodwill impairment	0	0	2,840,000
Loss (gain) on disposal of property, plant and equipment	70,000	(2,000)	(154,000)
Provision for doubtful accounts	516,000	532,000	816,000
Noncash retirement plan expense	775,000	705,000	598,000
Other	220,000	141,000	10,000
Changes in:
Accounts receivable	708,000	16,536,000	(8,533,000)
Inventories	(9,398,000)	8,144,000	(9,150,000)
Other assets and current assets	(2,894,000)	5,291,000	(10,728,000)
Accounts payable and accrued liabilities	(2,684,000)	(6,033,000)	2,948,000
Federal and state income taxes receivable/payable	3,864,000	(1,455,000)	(1,863,000)
Net cash provided by operating activities	46,275,000	73,213,000	24,219,000
Cash flows from investing activities:
Marketable securities purchased	(20,170,000)	(8,976,000)	(6,151,000)
Marketable securities - maturities and sales	10,306,000	22,959,000	25,263,000
Purchase of property, plant and equipment	(6,461,000)	(11,287,000)	(36,256,000)
Acquisition of customer contract			(21,968,000)
Sale of property, plant and equipment	25,000	307,000	409,000
Acquisition of businesses, net of cash acquired		(10,534,000)
Net cash used in investing activities	(16,300,000)	(7,531,000)	(38,703,000)
Cash flows from financing activities:
Dividends paid	(28,114,000)	(34,954,000)
Proceeds from sale of treasury stock	323,000	362,000
Other	(5,000)
Net cash used in financing activities	(27,796,000)	(34,592,000)
Net increase (decrease) in cash and cash equivalents	2,179,000	31,090,000	(14,484,000)
Cash and cash equivalents at beginning of period	54,043,000	22,953,000	37,437,000
Cash and cash equivalents at end of period	56,222,000	54,043,000	22,953,000
Supplemental disclosures of cash flow information:
Income taxes	$ 21,930,000	$ 17,411,000	$ 19,076,000