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Stock-Based and Other Long-Term Incentive Compensation (Summary of Unvested Stock Options) (Details) - USD ($)	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Shares
Unvested, beginning of period (in shares)	10,433
Granted (in shares)	5,000
Vested (in shares)	(10,433)
Unvested, end of period (in shares)	5,000
Weighted AverageGrant Date Fair Value Per Share
Unvested, weighted average grant date fair value, beginning of period (in USD per share)	$ 11.93
Unvested, weighted average grant date fair value, granted (in USD per share)	2.07
Vested, weighted average grant date fair value (in USD per share)	11.93
Unvested, weighted average grant date fair value, end of period (in USD per share)	$ 2.07
Stock Options
Weighted AverageGrant Date Fair Value Per Share
Unrecognized compensation cost related to unvested options	$ 8,000
Share-based compensation expense	$ 18,000	$ 92,000

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Gross number of share options (or share units) granted during the period.

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