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Summary of Significant Accounting Policies Foreign Currency Adjustments (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Net foreign translation and transaction activity	$ 88,000	$ 30,000	$ 89,000

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Net foreign translation and transaction activity

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