Note 9 - Product Warranty Obligations - Deferred Product Obligations (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current portion - other accrued liabilities	$ 25,396	$ 20,576
Long-term portion - other long-term liabilities	16,389	14,846
Total	41,785	35,422	$ 31,695	$ 30,197
Current portion - other accrued liabilities	13,646	11,017
Long-term portion - other long-term liabilities	54,694	46,837
Total	$ 68,340	$ 57,854	$ 36,139	$ 31,956

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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