Commitments and Contingencies Extended Warranty (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Ending balance	$ 74,900	$ 61,000
Less: current portion of unearned revenue for extended warranty	42,712	37,369
Extended Warranty [Member]
Beginning balance	24,448	14,637
Unearned revenue for new extended warranties	8,832	11,099
Unearned revenue recognized	(1,390)	(1,233)
Effect of change in exchange rates	70	(55)
Ending balance	31,960	24,448
Less: current portion of unearned revenue for extended warranty	2,031	1,305
Long-term unearned revenue for extended warranty within Other long-term obligations	$ 29,929	$ 23,143

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

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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.

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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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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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