Consolidated Statements Of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities:
Net earnings	$ 41,252,000	$ 38,875,000	$ 47,968,000
Adjustments to reconcile net earnings to net cash provided by operating activities:
Provision for depreciation	8,277,000	10,136,000	9,037,000
Change in contingent consideration liability	(3,000,000)
Goodwill impairment	2,840,000	0	0
Loss (gain) on disposal and impairment of property, plant and equipment	(154,000)	5,843,000	10,000
Provision for doubtful accounts	816,000	5,629,000	1,037,000
Deferred income tax provision (benefit)	239,000	(4,792,000)	5,096,000
Intangibles amortization	667,000	1,049,000	0
Other	608,000	568,000	618,000
Changes in:
Accounts receivable	(8,533,000)	(6,546,000)	16,936,000
Inventories	(9,150,000)	11,091,000	(10,284,000)
Other current assets	(10,728,000)	10,360,000	(6,729,000)
Accounts payable and accrued liabilities	2,948,000	(9,999,000)	(711,000)
Federal and state income taxes	(1,863,000)	128,000	(4,292,000)
Net cash provided by operating activities	24,219,000	62,342,000	58,686,000
Cash flows from investing activities:
Marketable securities purchased	(6,151,000)	(26,023,000)	(40,962,000)
Marketable securities - maturities and sales	25,263,000	29,767,000	82,521,000
Acquisition of property, plant and equipment	(36,256,000)	(13,584,000)	(15,003,000)
Acquisition of customer contract	(21,968,000)
Notes issued		(3,500,000)	(220,000)
Sale of property, plant and equipment	409,000	8,000	6,000
Acquisition of businesses, net of cash acquired		(246,000)	(4,526,000)
Net cash provided by (used in) investing activities	(38,703,000)	(13,578,000)	21,816,000
Cash flows from financing activities:
Dividends paid		(86,106,000)	(56,665,000)
Other		784,000	439,000
Net cash used in financing activities		(85,322,000)	(56,226,000)
Net increase (decrease) in cash and cash equivalents	(14,484,000)	(36,558,000)	24,276,000
Cash and cash equivalents at beginning of period	37,437,000	73,995,000	49,719,000
Cash and cash equivalents at end of period	22,953,000	37,437,000	73,995,000
Supplemental disclosures of cash flow information:
Income taxes	$ 19,076,000	$ 26,532,000	$ 26,686,000