Aggregate Property Value

No definition available.

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Balance Type:	debit
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- Definition

Represents estimated market value of the underlying collateral.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Investment in securities.

+ References

No definition available.

+ Details

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

- Definition

Represents the number of performing mortgage loans.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents amount of unpaid principal balance of mortgage loans.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents number of transaction.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents percentage of estimated market value of the underlying collateral.

+ References

No definition available.

+ Details

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- Definition

Percentage Of Securities Acquired From Trust

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents rate of percentage of unpaid principal balance of loan acquired.

+ References

No definition available.

+ Details

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Namespace Prefix:	ajx_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Securities Percentage of Total UPB

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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Period Type:	instant

- Definition

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

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Balance Type:	na
Period Type:	instant

- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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- Details

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Subsequent Events - Narrative (Details) $ / shares in Units, $ in Millions			1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 26, 2021 shares	Jul. 19, 2021 USD ($) loanPool	Aug. 06, 2021 USD ($) transaction residentialRPL residentialNPL	Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($) loan	Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($) loan	Aug. 05, 2021 $ / shares
Subsequent Event [Line Items]
Aggregate unpaid principal balance of mortgage loans on real estate							$ 26.2
Estimated market value of the underlying collateral							44.2
Investment In securities				$ 232.9	$ 0.0	$ 232.9	$ 61.3
Subsequent event \| Manager and Servicer Employees \| Restricted stock
Subsequent Event [Line Items]
Shares granted (in shares) \| shares	152,700
Vesting period	4 years
Percentage of shares vesting	25.00%
Subsequent event \| Board of directors
Subsequent Event [Line Items]
Dividends payable, amount per share (in dollars per share) \| $ / shares								$ 0.21
Subsequent event \| Ajax Mortgage Loan Trust 2021-E \| Mortgage loans
Subsequent Event [Line Items]
Aggregate property value		$ 968.6
Subsequent event \| Ajax Mortgage Loan Trust 2021-E \| Class A Notes
Subsequent Event [Line Items]
Percentage of securities acquired from trust		0.1001
Subsequent event \| Ajax Mortgage Loan Trust 2021-E \| Class A Notes \| Mortgage loans
Subsequent Event [Line Items]
Original Principal		$ 517.7
Interest Rate		1.82%
Subsequent event \| Corporate Joint Venture \| Ajax Mortgage Loan Trust 2021-E \| Mortgage loans
Subsequent Event [Line Items]
Investment In securities		$ 53.1
Subsequent event \| Corporate Joint Venture \| Ajax Mortgage Loan Trust 2021-E \| Class A Notes
Subsequent Event [Line Items]
Securities percentage of total UPB		83.00%
Performing Financial Instruments and Nonperforming Financial Instruments \| Subsequent event \| Ajax Mortgage Loan Trust 2021-E
Subsequent Event [Line Items]
Number of mortgage loans on real estate \| loanPool		3,142
Residential RPLs
Subsequent Event [Line Items]
Number of mortgage loans on real estate \| loan				38	0	237	26
Aggregate unpaid principal balance of mortgage loans on real estate				$ 5.2		$ 41.2	$ 2.0
Residential RPLs \| Eight sellers \| Subsequent event
Subsequent Event [Line Items]
Number of mortgage loans on real estate \| residentialRPL			31
Number of transaction \| transaction			6
Aggregate unpaid principal balance of mortgage loans on real estate			$ 4.7
Percentage of unpaid principal balance of loan acquired			80.90%
Percentage of estimated market value of the underlying collateral			55.10%
Estimated market value of the underlying collateral			$ 6.9
Residential NPLs
Subsequent Event [Line Items]
Number of mortgage loans on real estate \| loan				0	0	3	1
Aggregate unpaid principal balance of mortgage loans on real estate						$ 0.7	$ 0.2
Residential NPLs \| Two sellers \| Subsequent event
Subsequent Event [Line Items]
Number of mortgage loans on real estate \| residentialNPL			412
Number of transaction \| transaction			6
Aggregate unpaid principal balance of mortgage loans on real estate			$ 103.3
Percentage of unpaid principal balance of loan acquired			97.10%
Percentage of estimated market value of the underlying collateral			64.40%
Estimated market value of the underlying collateral			$ 155.8