CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
CONDENSED CONSOLIDATED BALANCE SHEETS
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, rate (as a percent)	6.00%	6.00%
Preferred stock, liquidation preference (in dollars per share)	$ 50	$ 50
Preferred stock, shares outstanding	4,870,000	5,613,000
Common shares, par value (in dollars per share)	$ 0.05	$ 0.05
Common shares, shares authorized	16,000,000	16,000,000
Common shares, shares issued	8,389,000	8,324,000
Treasury shares, at cost	1,090,000	1,056,000

Face amount or stated value per share of common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

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No definition available.

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- Definition

The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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