Note 7 - Guarantees and Other Obligations - Changes in Accrued Warranty (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Balance at beginning of period	$ 4,849	$ 4,350
Warranty expense accruals	1,582	1,736
Warranty payments	(1,515)	(1,191)
Warranty liability assumed		50
Balance at end of period	$ 4,916	$ 4,945

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.

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Amount of increase in the standard and extended product warranty accrual from a business acquisition.

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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.

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Amount of increase in the standard and extended product warranty accrual from warranties issued.

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