Note 12 - Warranty Accrual - Warranty Accrual and Payment Activity (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Balance at beginning of period	$ 21,909	$ 20,678	$ 15,328
Expense provisions	14,513	10,769	8,905
Cash payments	(11,573)	(10,879)	(11,017)
Adjustments	3,413	1,341	7,462
Balance at end of period	$ 28,262	$ 21,909	$ 20,678

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03.15(5))
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Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

+ References

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Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.

+ References

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-Publisher FASB
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The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

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