Note 10 - Product Warranty Obligations - Deferred Product Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Current portion - other accrued liabilities	$ 27,109		$ 25,396
Long-term portion - other long-term liabilities	19,387		16,389
Total	46,496	$ 45,324	41,785	$ 40,555	$ 38,660	$ 35,422
Current portion - other accrued liabilities	15,924		13,646
Long-term portion - other long-term liabilities	60,938		54,694
Total	$ 76,862	$ 74,517	$ 68,340	$ 64,921	$ 63,007	$ 57,854

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
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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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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.

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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.

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No definition available.

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