Consolidation of Variable Interest Entities - Schedule of Accrual Status of Residential Mortgage Loans of Consolidated VIE (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Variable Interest Entity [Line Items]
Loans Receivable, Fair Value Disclosure	$ 29,484	$ 29,697
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Loans Receivable, Fair Value Disclosure	225,004	7,442
Variable Interest Entity, Primary Beneficiary \| Business Purpose Residential Mortgage Loans
Variable Interest Entity [Line Items]
Loans Receivable, Fair Value Disclosure	4,548	$ 7,442
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate	4,835
Difference	(287)
Variable Interest Entity, Primary Beneficiary \| Residential Mortgage Loans
Variable Interest Entity [Line Items]
Loans Receivable, Fair Value Disclosure	220,456
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate	237,483
Difference	(17,027)
Less than 90 Days Past Due \| Accrual Status \| Variable Interest Entity, Primary Beneficiary \| Business Purpose Residential Mortgage Loans
Variable Interest Entity [Line Items]
Loans Receivable, Fair Value Disclosure	151
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate	151
Less than 90 Days Past Due \| Accrual Status \| Variable Interest Entity, Primary Beneficiary \| Residential Mortgage Loans
Variable Interest Entity [Line Items]
Loans Receivable, Fair Value Disclosure	219,118
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate	236,145
Difference	(17,027)
90 Days or More Past Due \| Non-accrual Status \| Variable Interest Entity, Primary Beneficiary \| Business Purpose Residential Mortgage Loans
Variable Interest Entity [Line Items]
Loans Receivable, Fair Value Disclosure	4,397
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate	4,684
Difference	(287)
90 Days or More Past Due \| Non-accrual Status \| Variable Interest Entity, Primary Beneficiary \| Residential Mortgage Loans
Variable Interest Entity [Line Items]
Loans Receivable, Fair Value Disclosure	1,338
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate	$ 1,338

The excess of the fair value amount over unpaid principal balance of loans.

No definition available.

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Namespace Prefix:	aaic_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI https://asc.fasb.org/subtopic&trid=2196772

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of 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 FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G))
-URI https://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

+ Details

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Period Type:	instant

- 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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- Details

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- Details

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Balance Type:
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- Details

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- Details

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- Details

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- Details

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- Details

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