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Income Taxes (Details) - USD ($)	12 Months Ended
Income Taxes (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Valuation Allowance [Line Items]
Expirations of capital loss carryforwards	$ 400,000
Re-measurement of net deferred tax asset due to enactment of new tax legislation	$ 0	$ 0	$ 1,365,000
Increase in effective tax rate (as a percent)	1.04%
Expired Capital Loss Carryforward
Valuation Allowance [Line Items]
Expirations of capital loss carryforwards	$ 0
Capital Loss Carryforward
Valuation Allowance [Line Items]
Valuation allowance	$ (86,000)	$ (36,000)