Commitments and Contingencies Extended Warranty (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Mar. 31, 2011	Mar. 31, 2010
Beginning balanace			$ 14,637	$ 5,870	$ 19,109	$ 9,665
Unearned revenue for new extended warranties	3,138	2,424	8,286	6,970
Unearned revenue recognized	(283)	(389)	(959)	(1,140)
Ending balance	21,964	11,700	21,964	11,700	19,109	9,665
Extended Warranties Unearned Revenue Current	1,162	1,147	1,162	1,147
Long-term unearned revenue for extended warranty within Other long-term obligations	$ 20,802	$ 10,553	$ 20,802	$ 10,553

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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