Note 7 - Product Warranty Obligations (Details) - Deferred Product Obligations (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Product warranty liability
Current portion - other accrued liabilities	$ 22,893	$ 24,143
Long-term portion - other long-term liabilities	6,384	6,766
Total	29,277us-gaap_StandardProductWarrantyAccrual	30,909us-gaap_StandardProductWarrantyAccrual	31,907us-gaap_StandardProductWarrantyAccrual	33,734us-gaap_StandardProductWarrantyAccrual
Deferred revenue related to extended warranty
Current portion - other accrued liabilities	4,857	4,519
Long-term portion - other long-term liabilities	22,674	22,674
Total	$ 27,531us-gaap_ExtendedProductWarrantyAccrual	$ 27,193us-gaap_ExtendedProductWarrantyAccrual	$ 24,632us-gaap_ExtendedProductWarrantyAccrual	$ 23,092us-gaap_ExtendedProductWarrantyAccrual

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- Definition

Amount as of the balance sheet date of the aggregate extended product warranty liability. Does not include the ending balance for the standard product warranty liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (c)(1),(c)(5)

-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

+ Details

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- Definition

Amount at end of the reporting period of the aggregate extended product warranty liability that is expected to be paid within one year of the balance sheet date or normal operating cycle, if longer. Does not include the balance for the standard product warranty liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Amount at end of the reporting period of the aggregate extended product warranty liability that is expected to be paid after one year from the balance sheet date or normal operating cycle, if longer. Does not include the balance for the standard product warranty liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.24)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ References

+ Details

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Amount as of the balance sheet date of the aggregate standard product warranty liability that is expected to be paid within one year or the normal operating cycle, if longer. Does not include the balance for the extended product warranty liability.

+ References

No definition available.

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Amount as of the balance sheet date of the aggregate standard product warranty liability that is expected to be paid after one year or beyond the normal operating cycle, if longer. Does not include the balance for the extended product warranty liability.

+ References

No definition available.

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