Restructuring Activities (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Activity and liability balances related to restructuring charges [Roll Forward]
Liability, Beginning balance	$ 0us-gaap_RestructuringReserve	$ 122,000us-gaap_RestructuringReserve
New Charges	1,832,000us-gaap_RestructuringCharges	1,387,000us-gaap_RestructuringCharges	5,245,000us-gaap_RestructuringCharges
Cash Payment and Other Settlements	(1,832,000)	(1,509,000)
Liability, Ending balance	0us-gaap_RestructuringReserve	0us-gaap_RestructuringReserve	122,000us-gaap_RestructuringReserve
Restructuring costs	1,832,000us-gaap_RestructuringCharges	1,387,000us-gaap_RestructuringCharges	5,245,000us-gaap_RestructuringCharges
Severance costs			3,200,000us-gaap_SeveranceCosts1
Asset disposals			1,400,000
Other expenses			600,000us-gaap_OtherRestructuringCosts
Severance Costs [Member]
Activity and liability balances related to restructuring charges [Roll Forward]
Liability, Beginning balance	0	122,000
New Charges	1,778,000	1,239,000
Cash Payment and Other Settlements	(1,778,000)	(1,361,000)
Liability, Ending balance	0	0
Restructuring costs	1,778,000	1,239,000
Transportation of Equipment [Member]
Activity and liability balances related to restructuring charges [Roll Forward]
Liability, Beginning balance	0	0
New Charges	0	100,000
Cash Payment and Other Settlements	0	(100,000)
Liability, Ending balance	0	0
Restructuring costs	0	100,000
Other Restructuring Costs [Member]
Activity and liability balances related to restructuring charges [Roll Forward]
Liability, Beginning balance	0	0
New Charges	54,000	48,000
Cash Payment and Other Settlements	(54,000)	(48,000)
Liability, Ending balance	0	0
Restructuring costs	$ 54,000	$ 48,000

The asset disposal costs related to the restructuring during the period.

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- Definition

Refers to the restructuring reserve settle with cash and with out cash previously accrued type of restructuring cost.

+ References

No definition available.

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- Definition

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.P.3)

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

+ References

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