Number of Payments Made on NPL Mortgage Loans

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Number of Payments Made on RPL Mortgage Loans

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Number of Recent Payments Made on RPL Mortgage Loans

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- Definition

Represents percentage of outstanding operating partnership units owned.

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Represents percentage of outstanding operating partnership units owned by an unaffiliated holder.

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- Definition

Percentage Of Ownership Interests In Joint Venture

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No definition available.

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- Definition

Amount of principal due on delinquent mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
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-Section S99
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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

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The number of units sold in a private placement of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 14
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Price of a single share of a number of saleable stocks of a company.

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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.

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No definition available.

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Organization and Basis of Presentation (Details Textuals)		12 Months Ended
	Nov. 22, 2019 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) payment	Dec. 31, 2018
Organization And Basis Of Presentation [Line Items]
Number of payments made on RPL mortgage loans (at least) \| payment		5
Number of recent payments made on RPL mortgage loans \| payment		7
Principal balance of small balance commercial mortgage loans (up to) \| $		$ 532,820,000
Number of payments made on NPL mortgage loans \| payment		3
Company ownership of subsidiary		100.00%
Percentage Of Outstanding Operating Partnership Units Owned		100.00%	96.80%
Percentage of outstanding OP units owned		100.00%	96.80%
Percentage of outstanding OP owned by an unaffiliated holder			3.20%
Maximum
Organization And Basis Of Presentation [Line Items]
Principal balance of small balance commercial mortgage loans (up to) \| $		$ 5,000,000.0
2018-C \| Great Ajax Corp
Organization And Basis Of Presentation [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent		63.00%
2017-D \| Great Ajax Corp
Organization And Basis Of Presentation [Line Items]
Percentage of ownership interests in joint venture		50.00%
Noncontrolling Interest, Ownership Percentage by Parent		50.00%
AS Ajax E II LLC
Organization And Basis Of Presentation [Line Items]
Ownership percentage		5.00%
Percentage of ownership interests in joint venture		53.10%
AS Ajax E II LLC \| Third Party
Organization And Basis Of Presentation [Line Items]
Ownership percentage by noncontrolling owners		46.90%
Thetis
Organization And Basis Of Presentation [Line Items]
Ownership percentage		19.80%
Gaea
Organization And Basis Of Presentation [Line Items]
Ownership percentage		23.20%
Share Price \| $ / shares	$ 15.00
Private placement share issuance \| shares	4,419,641
Proceeds from Issuance of Private Placement \| $	$ 66,300,000
Gaea \| Third Party
Organization And Basis Of Presentation [Line Items]
Ownership percentage by noncontrolling owners		76.80%
Great Ajax FS LLC
Organization And Basis Of Presentation [Line Items]
Ownership percentage		8.00%