Commitments, Contingencies and Legal Matters (Details) (USD $)	1 Months Ended	6 Months Ended
Feb. 28, 2009	Jul. 03, 2011	Dec. 31, 2010
Summary of changes in product warranties
Balance as of December 31, 2010		$ 17,617,000
Accruals for warranties issued during the period		3,663,000
Accruals related to pre-existing warranties (including changes in estimates)		521,000
Settlements made during the period (in cash or in kind)		(4,440,000)
Balance as of July 3, 2011		17,361,000
Commitments, Contingencies and Legal Matters (Textuals) [Abstract]
Total purchase commitments due through 2014		396,600,000
Company's percentage of take-or-pay agreement with SMP		51.00%
Terms in which take-or-pay agreement may be terminated by either party		Upon two years written notice
Warranty period for finished goods against defects in material and workmanship under normal use and service		one to three years
Jury award to GE for patent infringement	7,600,000
Outstanding obligation related to standby letters of credit		$ 3,500,000	$ 3,900,000

Commitments Contingencies And Legal Matters Textuals Abstract.

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Company's percentage of take-or-pay agreement.

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Outstanding obligations related to standby letters of credit.

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Short-term and long-term purchase commitments.

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Terms in which take or pay agreement may be terminated by either party.

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This element represents the gross amount awarded, to be received by, or to be remitted to the entity in settlement of litigation occurring during the period.

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Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

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-Paragraph 14
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Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty. Does not include any Increase or Decrease in the liability for payments related to extended product warranties.

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Represents the aggregate increase in the liability for accruals related to standard product warranties issued during the reporting period. Does not include any increase in the liability for accruals related to extended product warranties.

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Describes the nature of the product warranty, including the approximate term of the product warranty, how the product warranty arose, and the events or circumstances that would require the warrantor to perform under the product warranty.

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