CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
10% cumulative redeemable preferred stock par value per share (in usd per share)	$ 0.01	$ 0.01
10% cumulative redeemable preferred shares authorized (in shares)	50,000,000	50,000,000
10% cumulative redeemable preferred shares issued (in shares)	1,000	1,000
10% cumulative redeemable preferred shares outstanding (in shares)	1,000	1,000
Common stock par value per share (in usd per share)	$ 0.01	$ 0.01
Common shares authorized (in shares)	450,000,000	450,000,000
Common shares issued (in shares)	54,853,205	43,621,174
Common shares outstanding (in shares)	54,853,205	43,621,174
Assets of consolidated Variable Interest Entities	$ 1,482,292	$ 829,147
Liabilities of consolidated Variable Interest Entities	$ 1,134,493	$ 654,952

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

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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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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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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