Commitments and Contingencies Extended Warranty (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Beginning balanace	$ 17,193	$ 7,459	$ 14,637	$ 5,870
Unearned revenue for new extended warranties	2,215	2,587	5,148	4,546
Unearned revenue recognized	(299)	(381)	(676)	(751)
Ending balance, June 30	19,109	9,665	19,109	9,665
Extended Warranties Unearned Revenue Current	1,160	1,319	1,160	1,319
Long-term unearned revenue for extended warranty within Other long-term obligations	$ 17,949	$ 8,346	$ 17,949	$ 8,346

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

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- Definition

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

+ 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.

+ 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.

+ Details

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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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