Note 11 - Product Warranty Obligations - Deferred Product Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current portion - other accrued liabilities	$ 27,885	$ 25,396
Long-term portion - other long-term liabilities	21,431	16,389
Total	49,316	41,785	$ 35,422	$ 31,695
Current portion - other accrued liabilities	15,519	13,646
Long-term portion - other long-term liabilities	63,219	54,694
Total	$ 78,738	$ 68,340	$ 57,854	$ 36,139

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=68068213&loc=d3e12565-110249

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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://fasb.org/us-gaap/role/ref/legacyRef
-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

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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.

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

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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.

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