Stock Based Compensation, Stock Options Outstanding By Exercise Price Range (Details) - USD ($)	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Exercise Price Range 11.00 to 12.99 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, lower range limit (usd per share)	$ 11.00
Exercise price range, upper range limit (usd per share)	$ 12.99
Outstanding stock options, number (in shares)	311
Outstanding stock option, weighted average exercise price (in dollars per share)	$ 12.60
Outstanding stock option, weighted average remaining contractual life (years)	1 year 4 months 24 days
Exercisable stock options, number (in shares)	311
Exercisable stock option, weighted average exercise price (in dollars per share)	$ 12.60
Exercisable stock options, weighted average remaining contractual life (years)	1 year 4 months 24 days
Stock Options [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 0	$ 76,000
Share-based Payment Arrangement, Expense	$ 0	$ 0

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

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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