Other Financial Statement Data (Schedule Of Changes In Estimated Warranty Liability) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at beginning of period	$ 839	$ 798
Accrual for warranties	814	726
Warranty revision	(54)	(21)
Settlements made during the period	(599)	(683)
Balance at end of period	1,000	820
Current portion of estimated warranty liability	(943)	(784)	$ (793)
Long-term estimated warranty liability	$ 57	$ 36

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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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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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. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.

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

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Amount of decrease in the standard product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard product warranty. Excludes extended product warranties.

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

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