The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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Net amount of long-term deferred finance costs capitalized at the end of the reporting period.

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Amount of environmental remediation costs capitalized. These expenditures may relate to long-lived improvements in operating facilities.

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Amount of interest capitalized during the period.

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-Glossary Allowance for Funds Used during Construction

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Represents the assets associated with the entity's asset retirement obligations, which are not fully depreciated.

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Represents the future estimated annual expenditures related to asset retirement obligations.

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Summary of Significant Accounting Policies (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment
Construction in progress	$ 3,157us-gaap_ConstructionInProgressGross	$ 2,901us-gaap_ConstructionInProgressGross
Interest costs capitalized	0us-gaap_InterestCostsCapitalized	0us-gaap_InterestCostsCapitalized
Asset Retirement Obligations
ARO included in other liabilities and accrued expenses	1,261us-gaap_AssetRetirementObligation	1,320us-gaap_AssetRetirementObligation
Amount of assets associated with AROs not fully depreciated	274
Amount spent on AROs	113	138
Accretion expense recognized on AROs	57	61
Other Assets
Deferred financing costs	45	90
Other	100	105
Total	145us-gaap_OtherAssetsNoncurrent	195us-gaap_OtherAssetsNoncurrent
Environmental Expenditures
Capital expenditures related to environmental matters	1,038	395	428
Minimum
Asset Retirement Obligations
Estimated annual expenditures in years 2015 through 2019 relating to AROs	100
Maximum
Asset Retirement Obligations
Estimated annual expenditures in years 2015 through 2019 relating to AROs	$ 200
Buildings and building improvements \| Minimum
Property, Plant and Equipment
Estimated useful lives of property, plant and equipment	3 years
Buildings and building improvements \| Maximum
Property, Plant and Equipment
Estimated useful lives of property, plant and equipment	20 years
Machinery and equipment \| Minimum
Property, Plant and Equipment
Estimated useful lives of property, plant and equipment	2 years
Machinery and equipment \| Maximum
Property, Plant and Equipment
Estimated useful lives of property, plant and equipment	20 years
Furniture and fixtures \| Minimum
Property, Plant and Equipment
Estimated useful lives of property, plant and equipment	3 years
Furniture and fixtures \| Maximum
Property, Plant and Equipment
Estimated useful lives of property, plant and equipment	10 years
Automotive equipment. \| Minimum
Property, Plant and Equipment
Estimated useful lives of property, plant and equipment	3 years
Automotive equipment. \| Maximum
Property, Plant and Equipment
Estimated useful lives of property, plant and equipment	10 years