Discontinued Operations - (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net income (loss) from discontinued operations (Note 20)	$ 0	$ 0	$ (255,000)
Settled Litigation [Member] \| AMETEK Matter [Member] \| Guarantee Obligations [Member] \| Sisd [Member] \| Discontinued Operations, Disposed of by Sale [Member]
Loss contingency, damages awarded, refund of product purchase price, value			326,000
Loss contingency, damages awarded, reimbursement of legal fees, value			45,000
Litigation settlement, expense			281,000
Legal fees			123,000
Income tax expense (benefit) on discontinued operations			(149,000)
Net income (loss) from discontinued operations (Note 20)			$ (255,000)

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Loss Contingency, Damages Awarded, Reimbursement Of Legal Fees, Value

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

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