Number of non controlling interest subsidiaries

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- Definition

Represents percentage of outstanding operating partnership units owned.

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No definition available.

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- Definition

Percentage Of Ownership Interests In Joint Venture

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No definition available.

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- Definition

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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No definition available.

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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

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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- Definition

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.

+ References

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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

Amount of cash inflow from capital contributions to an entity associated with a dividend reinvestment plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

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- Definition

Number of shares of common and preferred stock issued as dividends during the period. Excludes stock splits.

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- Definition

Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

+ References

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- Definition

Value of stock issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

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- Definition

Amount of stock repurchase plan authorized.

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No definition available.

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- Definition

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

+ References

No definition available.

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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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The number of units or equivalent units outstanding for all classes.

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Equity - Narrative (Details)	3 Months Ended
Equity - Narrative (Details)	Mar. 31, 2020 USD ($) numberOfLoanPools $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) $ / shares shares	Mar. 24, 2020 $ / shares	Mar. 17, 2020 $ / shares	Jun. 30, 2019 shares	Dec. 31, 2018 shares
Class of Stock [Line Items]
Percentage Of Outstanding Operating Partnership Units Owned	100.00%						96.80%
Common stock shares outstanding (in shares)	22,921,935	22,142,143
Common stock par value per share (in dollars per share) \| $ / shares	$ 0.01	$ 0.01
Common stock shares authorized (in shares)	125,000,000	125,000,000
Preferred stock shares outstanding (in shares)	0	0
Preferred stock shares authorized (in shares)	25,000,000	25,000,000
Treasury Stock, Shares	37,278	33,248
Sale of common stock pursuant to dividend reinvestment plan \| $	$ 0		$ 72,000
Operating partnership units						624,106
Percentage of ownership interests in joint venture	34.00%
Common Stock, Shares, Issued	22,921,935	22,142,143
Dividends declared and distributions (in shares)	781,222
Dividends Payable, Amount Per Share \| $ / shares	$ 0.32		$ 0.32	$ 0.32
Shares Issued, Price Per Share \| $ / shares					$ 9.14
Number of non controlling interest subsidiaries \| numberOfLoanPools	4
At-the-Market Program
Class of Stock [Line Items]
Common stock authorized \| $	$ 50,000,000.0
Common Stock, Shares, Issued	0		0
Common Stock
Class of Stock [Line Items]
Common stock shares outstanding (in shares)	22,921,935	22,142,143	18,967,223				18,909,874
Issuance of shares under dividend reinvestment plan (in shares)	0		5,321
Sale of common stock pursuant to dividend reinvestment plan \| $			$ 100,000
Dividends declared and distributions (in shares)	781,222
Total Stockholders’ Equity
Class of Stock [Line Items]
Conversion of OP Units \| $		$ 10,800,000
2017-D
Class of Stock [Line Items]
Percentage of ownership interests in joint venture	50.00%
2017-D \| Great Ajax Corp
Class of Stock [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	50.00%
AS Ajax E II LLC
Class of Stock [Line Items]
Percentage of ownership interests in joint venture	53.10%
AS Ajax E II LLC \| Third Party
Class of Stock [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	46.90%
2018-C \| Great Ajax Corp
Class of Stock [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	63.00%
2018-C \| Third Party Institutional Investor
Class of Stock [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	37.00%
DG Brooklyn Holdings \| Great Ajax Corp
Class of Stock [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	95.00%
DG Brooklyn Holdings \| Third Party
Class of Stock [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	5.00%
BLFD Holding LLC \| Great Ajax Corp
Class of Stock [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	90.00%
BLFD Holding LLC \| Third Party Institutional Investor
Class of Stock [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	10.00%
Great Ajax II REIT
Class of Stock [Line Items]
Company ownership percentage	99.80%
Great Ajax II REIT \| Third Party
Class of Stock [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	0.20%