Condensed Consolidated Balance Sheets [Parenthetical] - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Allowance related to accounts receivable	$ 448		$ 448
Common stock, par value (in dollars per share)	$ 0.0001		$ 0.0001
Common stock, shares authorized (in shares)	150,000,000		150,000,000
Common stock, shares issued (in shares)	95,384,194		91,584,460
Common stock, shares outstanding (in shares)	95,384,194		91,584,460
Treasury stock, shares (in shares)	253,598		253,598
Series C-1 Preferred Stock
Redeemable preferred stock, dividend rate, percentage	9.75%	9.75%
Mezzanine equity, shares authorized (in shares)	10,000,000		10,000,000
Mezzanine equity, shares issued (in shares)	100,000		100,000
Mezzanine equity, shares outstanding (in shares)	100,000		100,000
Mezzanine equity, stated value (in dollars per share)	$ 1,233		$ 1,203
Series C-2 Preferred Stock
Redeemable preferred stock, dividend rate, percentage	9.75%	9.75%
Mezzanine equity, shares authorized (in shares)	10,000,000		10,000,000
Mezzanine equity, shares issued (in shares)	25,000		25,000
Mezzanine equity, shares outstanding (in shares)	25,000		25,000
Mezzanine equity, stated value (in dollars per share)	$ 1,155		$ 1,128
Series D Preferred Stock
Redeemable preferred stock, dividend rate, percentage	8.25%	8.25%
Mezzanine equity, shares authorized (in shares)	10,000,000		10,000,000
Mezzanine equity, shares issued (in shares)	39,254		39,254
Mezzanine equity, shares outstanding (in shares)	39,254		39,254
Mezzanine equity, stated value (in dollars per share)	$ 1,130		$ 1,107
Series E Preferred Stock
Redeemable preferred stock, dividend rate, percentage	8.25%		8.25%
Mezzanine equity, shares authorized (in shares)	10,000,000		10,000,000
Mezzanine equity, shares issued (in shares)	60,000		60,000
Mezzanine equity, shares outstanding (in shares)	60,000		60,000
Mezzanine equity, stated value (in dollars per share)	$ 1,092		$ 1,069
Series F Preferred Stock
Redeemable preferred stock, dividend rate, percentage	9.00%		9.00%
Mezzanine equity, shares authorized (in shares)	10,000,000		10,000,000
Mezzanine equity, shares issued (in shares)	55,000		55,000
Mezzanine equity, shares outstanding (in shares)	55,000		55,000
Mezzanine equity, stated value (in dollars per share)	$ 1,100		$ 1,076

Temporary Equity, Dividend Rate, Percentage

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Amount of allowance for credit loss on accounts receivable, classified as current.

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Face amount or stated value per share of common stock.

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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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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Per share amount of par value or stated value of stock classified as temporary equity. 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.

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The maximum number of securities classified as temporary equity that are permitted to be issued by an entity's charter and bylaws. 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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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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