Commitments and Contingencies Extended Warranty (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Beginning balanace	$ 24,448	$ 14,637
Unearned revenue for new extended warranties	2,946	2,933
Unearned revenue recognized	(300)	(377)
Effect of change in exchange rates	46	0
Ending balance	27,140	17,193
Extended Warranties Unearned Revenue Current	1,445	1,126
Long-term unearned revenue for extended warranty within Other long-term obligations	$ 25,695	$ 16,067

Amount as of the balance sheet date of unearned revenue for extended warranty contracts.

No definition available.

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- Definition

The current portion of the amount as of the balance sheet date of unearned revenue for extended warranty contracts.

+ References

No definition available.

+ Details

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- Definition

Represents the aggregate increase in the deferred revenue liability for accruals related to new extended product warranties issued during the reporting period.

+ References

No definition available.

+ Details

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- Definition

The long-term portion of the amount as of the balance sheet date of unearned revenue for extended warranty contracts.

+ References

No definition available.

+ Details

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- Definition

Increase or Decrease in extended product warranty liability attributable to currency translation. Does not include any Increase or Decrease in standard product warranty liability due to currency translation.

+ References

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

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 45

-Paragraph 14

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

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- Definition

The amount of previously reported deferred or unearned revenue that was recognized as revenue during the period. For cash flows, this element primarily pertains to amortization of deferred credits on long-term arrangements. As a noncash item, it is deducted from net income when calculating cash provided by or used in operations using the indirect method.

+ References

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

-Subsection 1

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

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

-URI http://asc.fasb.org/extlink&oid=6600647&loc=d3e214044-122780

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