The taxable dividends per share of common stock.

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Minimum Number of Quarters with No Dividends that Results in Voting Rights

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Preferred Stock, Shares Reserved For Future Issuance, Value

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Preferred Stock, Voting Rights, Number of Additional Directors Elected

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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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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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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 price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.

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The number of nonredeemable preferred stock (shares) (or preferred stock redeemable solely at the option of the issuer) allocated to investors to buy shares of a new issue of preferred stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds.

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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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Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation.

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Cash received on stock transaction after deduction of issuance costs.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Stockholders’ Equity - Narrative (Details) $ / shares in Units, $ in Thousands		1 Months Ended		12 Months Ended
	Oct. 13, 2017 USD ($) $ / shares	Oct. 31, 2019 USD ($) $ / shares shares	Oct. 31, 2017 shares	Dec. 31, 2019 USD ($) director quarter $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares	Nov. 27, 2019 shares	Mar. 28, 2019 shares
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)				200,000,000	200,000,000
Preferred stock, par value (in dollars per share) \| $ / shares				$ 0.01	$ 0.01
Preferred stock, shares issued (in shares)				20,872,888	12,000,000
Preferred stock, shares outstanding (in shares)				20,872,888	12,000,000
Liquidation preference (USD per share) \| $ / shares				$ 25
Preferred stock, redemption price per share (USD per share) \| $ / shares				25.00
Common stock dividend per share (in dollars per share) \| $ / shares				$ 0.80	$ 0.80	$ 0.80
Preferred stock issuance proceeds, net \| $				$ 215,073	$ 0	$ 130,496
Ordinary Income
Class of Stock [Line Items]
Common stock dividend per share (in dollars per share) \| $ / shares				$ 0.42	$ 0.37	$ 0.46
Capital Gain Distribution
Class of Stock [Line Items]
Common stock dividend per share (in dollars per share) \| $ / shares				0.13	0.12	0.17
Return of Capital
Class of Stock [Line Items]
Common stock dividend per share (in dollars per share) \| $ / shares				$ 0.25	$ 0.31	$ 0.17
Preferred Equity Distribution Agreement
Class of Stock [Line Items]
Preferred stock issuance proceeds, net \| $				$ 48,400
Preferred stock, available for future issuance \| $				$ 82,400
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)				3,156,087	3,000,000
Preferred stock, shares outstanding (in shares)				3,156,087	3,000,000
Preferred stock, dividend rate (as a percent)				7.75%	7.75%
Series C Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares issued (in shares)				4,181,807	3,600,000
Preferred stock, shares outstanding (in shares)				4,181,807	3,600,000
Preferred stock, dividend rate (as a percent)				7.875%	7.875%
Preferred stock, shares subscribed but unissued (in shares)								2,460,000
Series D Preferred Stock
Class of Stock [Line Items]
Preferred stock, par value (in dollars per share) \| $ / shares	$ 0.01
Preferred stock, shares issued (in shares)				6,123,495	5,400,000
Preferred stock, shares outstanding (in shares)				6,123,495	5,400,000
Preferred stock, dividend rate (as a percent)				8.00%	8.00%
Liquidation preference (USD per share) \| $ / shares				$ 25
Proceeds from sale of stock \| $	$ 130,500
Preferred stock, shares subscribed but unissued (in shares)								2,650,000
Series D Preferred Stock \| Underwritten Public Offering
Class of Stock [Line Items]
Shares issued in transaction (in shares)			5,400,000
Series E Preferred Stock
Class of Stock [Line Items]
Preferred stock, par value (in dollars per share) \| $ / shares		$ 0.01
Preferred stock, shares issued (in shares)				7,411,499
Preferred stock, shares outstanding (in shares)				7,411,499
Preferred stock, dividend rate (as a percent)				7.875%
Preferred stock, shares subscribed but unissued (in shares)							3,000,000
Series E Preferred Stock \| Underwritten Public Offering
Class of Stock [Line Items]
Shares issued in transaction (in shares)		6,900,000
Liquidation preference (USD per share) \| $ / shares		$ 25
Proceeds from sale of stock \| $		$ 166,700
Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)				30,900,000	30,900,000
Preferred stock, shares issued (in shares)				20,872,888	12,000,000
Preferred stock, shares outstanding (in shares)				20,872,888	12,000,000
Minimum number of quarters without dividends that result in voting rights \| quarter				6
Number of additional directors elected \| director				2