Commitments and Contingencies (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Insurance receivable	$ 0	$ 2,241,000
Accrual for non-conformance issues	146,000
Changes in warranty liability	0	0	$ 0
Product warranty accrual	159,000	$ 159,000	$ 159,000
Standby Letters of Credit \| Cash Collateral Security Agreement
Amount of letters of credit outstanding	$ 2,461,000

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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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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Amount of increase (decrease) in the standard product warranty accrual. Excludes extended product warranties.

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