Share-based Compensation - Additional Information (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Restricted Shares [Member]
Stock Based Compensation [Abstract]
Unrecognized compensation cost	$ 273,000	$ 284,000
Performance-Based Restricted Stock Units [Member]
Stock Based Compensation [Abstract]
Vesting period	3 years
Stock Incentive Plan [Member]
Stock Based Compensation [Abstract]
Number of shares authorized (in shares)	350,000
Stock Incentive Plan [Member] \| Restricted Shares [Member]
Stock Based Compensation [Abstract]
Recognition period for total unrecognized compensation costs	3 years
Stock Incentive Plan [Member] \| Restricted Shares [Member] \| Nonemployee Director [Member]
Stock Based Compensation [Abstract]
Compensation expense	$ 125,000	129,000
Stock Incentive Plan [Member] \| Performance-Based Restricted Stock Units [Member]
Stock Based Compensation [Abstract]
Unrecognized compensation cost	106,000	200,000
Stock Incentive Plan [Member] \| Performance-Based Restricted Stock Units [Member] \| Certain Executive Officers [Member]
Stock Based Compensation [Abstract]
Compensation expense	$ (112,000)	$ 25,000

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

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-Publisher FASB
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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Number of shares authorized for issuance under share-based payment arrangement.

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