Commitments and Contingencies Extended Warranty (Details) (USD $) In Thousands, unless otherwise specified			3 Months Ended	9 Months Ended
Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Extended Warranty [Member]	Sep. 30, 2012 Extended Warranty [Member]	Sep. 30, 2013 Extended Warranty [Member]	Sep. 30, 2012 Extended Warranty [Member]
Beginning balance	$ 77,100	$ 74,900	$ 33,395	$ 29,011	$ 31,960	$ 24,448
Unearned revenue for new extended warranties			1,010	2,080	3,635	7,269
Unearned revenue recognized			(597)	(351)	(1,592)	(982)
Effect of change in exchange rates			55	95	(140)	100
Ending balance	77,100	74,900	33,863	30,835	33,863	30,835
Less: current portion of unearned revenue for extended warranty	43,953	42,712	2,454	1,800	2,454	1,800
Long-term unearned revenue for extended warranty within Other long-term obligations			$ 31,409	$ 29,035	$ 31,409	$ 29,035

Total Increase or Decrease in the deferred revenue liability due to currency translation.

No definition available.

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

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-SubTopic 10

-Section S99

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Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

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-Subparagraph (SAB TOPIC 13.A.4(a).Q1)

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The noncurrent portion of deferred revenue amount as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Amount of previously reported deferred or unearned revenue that was recognized as revenue during the period. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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