Related Party Transactions - Schedule Statement of Income of Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Related Party Transaction [Line Items]
Related party expense – loan servicing fees	$ 2,014	$ 2,506
Related party expense – management fee	1,799	1,688
Loss on sale of mortgage loans	(705)	0
Interest Income
Related Party Transaction [Line Items]
Amount of transaction	2,019	2,416
Gregory \| Loan Servicing Fees
Related Party Transaction [Line Items]
Related party expense – loan servicing fees	2,014	2,506
Thetis \| Management fees
Related Party Transaction [Line Items]
Related party expense – management fee	1,799	1,688
Thetis \| Income from investments in affiliate
Related Party Transaction [Line Items]
Amount of transaction	(966)	279
Great Ajax FS \| Income from investments in affiliate
Related Party Transaction [Line Items]
Amount of transaction	(276)	128
Gaea \| Gain/Loss on sale of Mortgage Loans
Related Party Transaction [Line Items]
Loss on sale of mortgage loans	$ (705)	$ 0

Represents the amount related to loan servicing fee expense as related party expense.

No definition available.

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Namespace Prefix:	ajx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the amount related to management fee expense as related party expense.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
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+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of transactions with related party during the financial reporting period.

+ References

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+ Details

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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.

+ References

No definition available.

+ Details

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