Commitments and Contingencies - Warranty (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Warranty
Balance, beginning of the year	$ 7,852	$ 6,532	$ 4,217
Warranties issued	5,865	6,737	5,817
Addition from Ultratech acquisition			1,889
Consumption of reserves	(6,242)	(6,573)	(6,330)
Changes in estimate	(408)	1,156	939
Balance, end of the year	$ 7,067	$ 7,852	$ 6,532

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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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- Definition

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

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

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