Consolidated Statements Of Cash Flows (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net earnings	$ 26,477,000us-gaap_NetIncomeLoss	$ 41,252,000us-gaap_NetIncomeLoss	$ 38,875,000us-gaap_NetIncomeLoss
Adjustments to reconcile net earnings to net cash provided by operating activities:
Intangibles amortization	11,991,000us-gaap_AmortizationOfIntangibleAssets	667,000us-gaap_AmortizationOfIntangibleAssets	1,049,000us-gaap_AmortizationOfIntangibleAssets
Provision for depreciation	9,828,000us-gaap_Depreciation	8,277,000us-gaap_Depreciation	10,136,000us-gaap_Depreciation
Deferred income tax provision (benefit)	(1,005,000)us-gaap_DeferredIncomeTaxExpenseBenefit	239,000us-gaap_DeferredIncomeTaxExpenseBenefit	(4,792,000)us-gaap_DeferredIncomeTaxExpenseBenefit
Impairment of finite lived intangible assets	2,063,000
Change in contingent consideration liability		(3,000,000)
Goodwill impairment	0us-gaap_GoodwillImpairmentLoss	2,840,000us-gaap_GoodwillImpairmentLoss	0us-gaap_GoodwillImpairmentLoss
Loss (gain) on disposal and impairment of property, plant and equipment	(2,000)	(154,000)	5,843,000
Provision for doubtful accounts	532,000us-gaap_ProvisionForDoubtfulAccounts	816,000us-gaap_ProvisionForDoubtfulAccounts	5,629,000us-gaap_ProvisionForDoubtfulAccounts
Other	846,000us-gaap_OtherNoncashIncomeExpense	608,000us-gaap_OtherNoncashIncomeExpense	568,000us-gaap_OtherNoncashIncomeExpense
Changes in:
Accounts receivable	16,536,000	(8,533,000)	(6,546,000)
Inventories	8,144,000us-gaap_IncreaseDecreaseInInventories	(9,150,000)us-gaap_IncreaseDecreaseInInventories	11,091,000us-gaap_IncreaseDecreaseInInventories
Other current assets	5,291,000	(10,728,000)	10,360,000
Accounts payable and accrued liabilities	(6,033,000)	2,948,000	(9,999,000)
Federal and state income taxes receivable/payable	(1,455,000)	(1,863,000)	128,000
Net cash provided by operating activities	73,213,000	24,219,000	62,342,000
Cash flows from investing activities:
Marketable securities purchased	(8,976,000)	(6,151,000)	(26,023,000)
Marketable securities - maturities and sales	22,959,000	25,263,000	29,767,000
Acquisition of property, plant and equipment	(11,287,000)	(36,256,000)	(13,584,000)
Acquisition of customer contract		(21,968,000)
Notes issued			(3,500,000)
Sale of property, plant and equipment	307,000	409,000	8,000
Acquisition of businesses, net of cash acquired	(10,534,000)		(246,000)
Net cash used in investing activities	(7,531,000)	(38,703,000)	(13,578,000)
Cash flows from financing activities:
Dividends paid	(34,954,000)us-gaap_PaymentsOfDividendsCommonStock		(86,106,000)us-gaap_PaymentsOfDividendsCommonStock
Other	362,000		784,000
Net cash used in financing activities	(34,592,000)		(85,322,000)
Net increase (decrease) in cash and cash equivalents	31,090,000	(14,484,000)	(36,558,000)
Cash and cash equivalents at beginning of year	22,953,000	37,437,000	73,995,000
Cash and cash equivalents at end of year	54,043,000	22,953,000	37,437,000
Supplemental disclosures of cash flow information:
Income taxes	$ 17,411,000us-gaap_IncomeTaxesPaid	$ 19,076,000us-gaap_IncomeTaxesPaid	$ 26,532,000us-gaap_IncomeTaxesPaid

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.