Commitments and Contingencies Extended Warranty (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Beginning balance			$ 76,600
Ending balance	$ 78,200		78,200
Less: current portion of unearned revenue for extended warranty	44,639		44,639		$ 43,436
Extended Warranty [Member]
Beginning balance	34,084	$ 33,958	34,138	$ 33,528
Unearned revenue for new extended warranties	826	987	2,251	2,837
Unearned revenue recognized	(716)	(633)	(2,029)	(2,037)
Effect of change in exchange rates	(187)	(121)	(353)	(137)
Ending balance	34,007	34,191	34,007	34,191
Less: current portion of unearned revenue for extended warranty	3,416	2,592	3,416	2,592
Deferred Revenue, Noncurrent	$ 30,591	$ 31,599	$ 30,591	$ 31,599

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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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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