Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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The number of positions eliminated during the period as a result of restructuring activities.

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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

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

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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.

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

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Restructuring Restructuring Plan (Details) (USD $)	3 Months Ended								12 Months Ended
Restructuring Restructuring Plan (Details) (USD $)	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 164,000us-gaap_RestructuringCharges	$ 227,000us-gaap_RestructuringCharges	$ 0us-gaap_RestructuringCharges	$ 0us-gaap_RestructuringCharges	$ 0us-gaap_RestructuringCharges	$ 0us-gaap_RestructuringCharges	$ 0us-gaap_RestructuringCharges	$ 2,254,000us-gaap_RestructuringCharges	$ 391,000us-gaap_RestructuringCharges	$ 2,254,000us-gaap_RestructuringCharges	$ 1,176,000us-gaap_RestructuringCharges
Restructuring Reserve, Current	701,000us-gaap_RestructuringReserveCurrent				49,000us-gaap_RestructuringReserveCurrent				701,000us-gaap_RestructuringReserveCurrent	49,000us-gaap_RestructuringReserveCurrent
May 2012 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Number of Positions Eliminated										42
Restructuring Reserve											49,000	149,000
Restructuring charges										0	1,200,000
Payments for Restructuring										49,000	100,000
Restructuring Reserve, Current					0					0	49,000
February 2013 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Number of Positions Eliminated										43
Restructuring Reserve											0
Restructuring charges										2,522,000
Payments for Restructuring										2,522,000
Restructuring Reserve, Current					0					0
2014 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Number of Positions Eliminated									44
Restructuring Reserve					0					0
Restructuring charges									1,841,000
Payments for Restructuring									1,140,000
Restructuring Reserve, Current	$ 701,000								$ 701,000