Represents estimated market value of the underlying collateral.

No definition available.

Name:	ajx_EstimatedMarketValueOfUnderlyingCollaterals
Namespace Prefix:	ajx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the number of performing mortgage loans.

+ References

No definition available.

+ Details

Name:	ajx_MortgageLoansOnRealEstateCommitmentsToPurchaseNumber
Namespace Prefix:	ajx_
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

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

- Definition

Represents the number of sellers.

+ References

No definition available.

+ Details

Name:	ajx_NumberOfSellers
Namespace Prefix:	ajx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents number of transaction.

+ References

No definition available.

+ Details

Name:	ajx_NumberOfTransaction
Namespace Prefix:	ajx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Payments to acquire loans

+ References

No definition available.

+ Details

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

- Definition

Represents percentage of estimated market value of the underlying collateral.

+ References

No definition available.

+ Details

Name:	ajx_PercentageOfEstimatedMarketValueOfUnderlyingCollateral
Namespace Prefix:	ajx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

Name:	ajx_PercentageOfUnpaidPrincipalBalanceOfLoanAcquired
Namespace Prefix:	ajx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

+ Details

Name:	us-gaap_DividendsPayableAmountPerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

Name:	us-gaap_StockRepurchaseProgramAuthorizedAmount1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_BoardOfDirectorsChairmanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=ajx_TwoSellersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentPerformanceStatusAxis=ajx_ReperformingMortgageLoansOnRealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=us-gaap_CorporateJointVentureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentPerformanceStatusAxis=ajx_NonperformingMortgageLoansOnRealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentPerformanceStatusAxis=ajx_SmallBalanceCommercialMortgageLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Subsequent Events - Narrative (Details) - Subsequent events $ / shares in Units, $ in Millions	2 Months Ended
	Mar. 03, 2020 USD ($) numberOfLoanPools	Feb. 28, 2020 USD ($)	Feb. 25, 2020 $ / shares
Subsequent Event [Line Items]
Common stock authorized		$ 25.0
Board of Directors Chairman
Subsequent Event [Line Items]
Dividends payable, amount per share (in dollars per share) \| $ / shares			$ 0.32
Two Sellers
Subsequent Event [Line Items]
Number Of Sellers \| numberOfLoanPools	2
Number Of Transaction \| numberOfLoanPools	2
Re-performing loans
Subsequent Event [Line Items]
Estimated Market Value Of Underlying Collaterals	$ 469.0
Re-performing loans \| Corporate Joint Venture [Member]
Subsequent Event [Line Items]
Number of mortgage loans on real estate \| numberOfLoanPools	1,943
Percentage Of Estimated Market Value Of Underlying Collateral	66.00%
Percentage Of Unpaid Principal Balance Of Loan Acquired	91.50%
Payments to acquire loans	$ 309.3
Re-performing loans \| Two Sellers
Subsequent Event [Line Items]
Number of mortgage loans on real estate \| numberOfLoanPools	27
Estimated Market Value Of Underlying Collaterals	$ 3.7
Percentage Of Estimated Market Value Of Underlying Collateral	37.70%
Aggregate unpaid principal balance of mortgage loans on real estate	$ 2.2
Percentage Of Unpaid Principal Balance Of Loan Acquired	63.80%
Non-performing loans
Subsequent Event [Line Items]
Estimated Market Value Of Underlying Collaterals	$ 134.6
Non-performing loans \| Corporate Joint Venture [Member]
Subsequent Event [Line Items]
Number of mortgage loans on real estate \| numberOfLoanPools	334
Percentage Of Estimated Market Value Of Underlying Collateral	60.50%
Percentage Of Unpaid Principal Balance Of Loan Acquired	77.00%
Payments to acquire loans	$ 81.5
SBC loan pools
Subsequent Event [Line Items]
Estimated Market Value Of Underlying Collaterals	$ 6.2
SBC loan pools \| Corporate Joint Venture [Member]
Subsequent Event [Line Items]
Number of mortgage loans on real estate \| numberOfLoanPools	2
Percentage Of Estimated Market Value Of Underlying Collateral	52.40%
Percentage Of Unpaid Principal Balance Of Loan Acquired	100.00%
Payments to acquire loans	$ 3.2