Note 12 - Warranty Accrual - Warranty Accrual and Payment Activity (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Balance at beginning of period	$ 29,992	$ 25,113	$ 28,262	$ 21,909
Expense provisions	3,737	3,749	7,085	6,347
Cash payments	(2,976)	(3,196)	(5,469)	(5,696)
Adjustments	(1,404)	0	(529)	3,106
Balance at end of period	$ 29,349	$ 25,666	$ 29,349	$ 25,666

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
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

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
-Name Accounting Standards Codification
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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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-Publisher FASB
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