Accrued Liabilities - Components of Accrued Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accrued Liabilities
Accrued product related costs	$ 5,216	$ 5,429
Accrued Income taxes	3,346us-gaap_AccruedIncomeTaxesCurrent	2,666us-gaap_AccruedIncomeTaxesCurrent
Accrued property and other taxes	2,547	1,718
Dividends payable	1,336us-gaap_DividendsPayableCurrent	1,342us-gaap_DividendsPayableCurrent
Remediation reserves	3,918	5,116	3,847
Other accrued liabilities	8,993us-gaap_OtherAccruedLiabilitiesCurrent	10,975us-gaap_OtherAccruedLiabilitiesCurrent
Accrued Liabilities, Current, Total	$ 25,356us-gaap_AccruedLiabilitiesCurrent	$ 27,246us-gaap_AccruedLiabilitiesCurrent

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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- Definition

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes.

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