Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash Flows from Operating Activities
Net earnings	$ 73,646us-gaap_NetIncomeLoss	$ 113,295us-gaap_NetIncomeLoss	$ 123,908us-gaap_NetIncomeLoss
Adjustments to arrive at net cash provided by operating activities:
Depreciation and amortization	51,456	52,016	48,352
Share-based compensation	6,265us-gaap_ShareBasedCompensation	8,430us-gaap_ShareBasedCompensation	10,086us-gaap_ShareBasedCompensation
Loss (gain) on assets	70,745us-gaap_GainLossOnDispositionOfAssets	695us-gaap_GainLossOnDispositionOfAssets	(869)us-gaap_GainLossOnDispositionOfAssets
Deferred income taxes	(16,780)	(6,178)	2,916
Changes in operating assets and liabilities:
Trade accounts receivable	(10,582)	3,466	(15,158)
Inventories	64us-gaap_IncreaseDecreaseInInventories	(30,217)us-gaap_IncreaseDecreaseInInventories	(23,125)us-gaap_IncreaseDecreaseInInventories
Prepaid expenses and other assets	6,479	616	(9,405)
Accounts payable and other accrued expenses	6,745	3,606	225
Accrued salaries, wages and withholdings from employees	(365)	5,384	(1,209)
Income taxes	7,047	(100)	(1,689)
Other liabilities	(5,532)	2,540	5,334
Net cash provided by operating activities	189,188	153,553	139,366
Cash Flows from Investing Activities
Acquisition of property, plant and equipment	(79,398)	(104,246)	(103,806)
Proceeds from sale of assets	1,029	6,225	1,364
Other investing activities	(780)	(208)	(242)
Net cash used in investing activities	(79,149)	(98,229)	(102,684)
Cash Flows from Financing Activities
Proceeds from additional borrowings	213,985us-gaap_ProceedsFromIssuanceOfDebt	194,973us-gaap_ProceedsFromIssuanceOfDebt	73,903us-gaap_ProceedsFromIssuanceOfDebt
Debt payments	(128,186)us-gaap_RepaymentsOfDebt	(198,686)us-gaap_RepaymentsOfDebt	(58,052)us-gaap_RepaymentsOfDebt
Purchase of treasury stock	(137,192)	0	(23,154)
Dividends paid	(47,893)us-gaap_PaymentsOfDividendsCommonStock	(45,513)us-gaap_PaymentsOfDividendsCommonStock	(43,426)us-gaap_PaymentsOfDividendsCommonStock
Proceeds from options exercised and other equity transactions	733	1,007	1,957
Net cash used in financing activities	(98,553)	(48,219)	(48,772)
Effect of exchange rate changes on cash and cash equivalents	(10,993)	(2,331)	4,297
Net increase (decrease) in cash and cash equivalents	493	4,774	(7,793)
Cash and cash equivalents at beginning of period	19,836	15,062	22,855
Cash and cash equivalents at end of period	20,329	19,836	15,062
Cash paid during the year for:
Interest	16,158us-gaap_InterestPaid	16,168us-gaap_InterestPaid	16,897us-gaap_InterestPaid
Income taxes	42,335us-gaap_IncomeTaxesPaid	47,436us-gaap_IncomeTaxesPaid	53,492us-gaap_IncomeTaxesPaid
Capitalized interest	$ 1,449us-gaap_InterestPaidCapitalized	$ 1,875us-gaap_InterestPaidCapitalized	$ 1,601us-gaap_InterestPaidCapitalized

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.