PROPERTY, PLANT, AND EQUIPMENT (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
PROPERTY, PLANT, AND EQUIPMENT
Property, plant and equipment	$ 405,264,000us-gaap_PropertyPlantAndEquipmentGross	$ 391,726,000us-gaap_PropertyPlantAndEquipmentGross
Accumulated depreciation	(240,245,000)	(253,833,000)
Property, plant, and equipment, net	165,019,000us-gaap_PropertyPlantAndEquipmentNet	137,893,000us-gaap_PropertyPlantAndEquipmentNet	124,838,000us-gaap_PropertyPlantAndEquipmentNet
Computer software costs included in construction in progress	12,600,000	10,200,000
Capitalized Computer Software, Additions	1,300,000	0
Interest Costs Capitalized	400,000us-gaap_InterestCostsCapitalized	200,000us-gaap_InterestCostsCapitalized	0us-gaap_InterestCostsCapitalized
Land and buildings
PROPERTY, PLANT, AND EQUIPMENT
Property, plant and equipment	120,165,000	117,653,000
Machinery and equipment
PROPERTY, PLANT, AND EQUIPMENT
Property, plant and equipment	261,415,000	255,390,000
Construction in progress
PROPERTY, PLANT, AND EQUIPMENT
Property, plant and equipment	$ 23,684,000	$ 18,683,000

Represents the amount of computer software costs included in the construction in progress.

No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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-Section S99

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-Name Regulation S-X (SX)

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- Definition

Additions made to capitalized computer software costs during the period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

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- Definition

Amount of interest capitalized during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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