Number of shares exchanged.

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Percentage of litigation claim.

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Percentage of ownership on outstanding stock by foreign entities.

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Percentage of threshold ownership in equity by foreign entities.

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Preferred stock, repurchase, offering price as percentage of liquidation preference.

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Purchase price percentage as of aggregate liquidation preference.

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Purchase price percentage as of liquidation preference.

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Redemption rate of preferred stock for cash.

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Stock requested to be repurchased during period shares.

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Stock requested to be repurchased during period value.

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Face amount or stated value per share of 10 3/4% Series B cumulative exchangeable redeemable preferred stock; generally not indicative of the fair market value per share.

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No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Adjustment to retained earnings for the increase in carrying amount of redeemable preferred stock that is classified as temporary equity.

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

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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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The cash inflow from issuance of preferred stock that is classified as callable.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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10 3/4% Series B Cumulative Exchangeable Redeemable Preferred Stock - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands								6 Months Ended	12 Months Ended	61 Months Ended
	Nov. 02, 2017	Oct. 15, 2013	Oct. 15, 2011	Oct. 15, 2010	Oct. 15, 2009	Apr. 05, 2004	Oct. 30, 2003	Jun. 30, 2018	Dec. 31, 2017	Oct. 30, 2008	Feb. 18, 2004
Series B Preferred Stock Litigation
Class Of Stock [Line Items]
Claiming percentage of litigation	94.16%
Series A Preferred Stock
Class Of Stock [Line Items]
Preferred stock par value per share							$ 0.01
Liquidation preference per share							$ 1,000
Gross proceeds from the issuance of Series A preferred Stock							$ 75,000
Series A Preferred Stock \| Private Placement
Class Of Stock [Line Items]
Preferred stock, shares issued							75,000
Series B Preferred Stock
Class Of Stock [Line Items]
Preferred stock, shares issued								90,549	90,549
Preferred stock par value per share											$ 0.01
Liquidation preference per share								$ 1,000			$ 1,000
Shares of Series B preferred stock exchanged for Series A preferred stock						76,702
Purchase price percentage as of aggregate liquidation preference								101.00%
Rate of redemption of Preferred stock for cash			100.00%	101.792%	103.583%
Rate of redemption of Preferred stock at purchase price								100.00%
Dividends on the Series B preferred stock								10.75%	10.75%
Increase in carrying value of preferred stock										$ 17,300
Stock requested to be repurchased		92,223
Purchase price of stock requested to be repurchased		$ 126,900
Stock repurchased		1,800
Purchase price of stock repurchased		$ 2,500
Offer price in cash as percentage of liquidation preference								101.00%
Aggregate cumulative unpaid dividends on outstanding shares								$ 79,899	$ 75,032
Series B Preferred Stock \| Maximum
Class Of Stock [Line Items]
Percentage of ownership on outstanding equity to be held by foreign entities								25.00%
Series B Preferred Stock \| Series B Preferred Stock Litigation \| Minimum
Class Of Stock [Line Items]
Percentage of collective ownership of outstanding stock by foreign entities								63.00%