Loans Held for Investment - Loan Products Type and Characteristics (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Unpaid Principal Balance	$ 11,517,084	$ 12,640,193
Seasoned Subprime Residential Mortgage Loans \| Loans Held for Investment at Fair Value
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Underlying mortgages excluded from portfolio	148,000
Residential Portfolio Segment
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Outstanding balance past due	$ 1,858,182	$ 2,351,150
% of Unpaid Principal Balance	16.20%	18.60%
Residential Portfolio Segment \| Bankruptcy
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Outstanding balance past due	$ 216,944	$ 277,098
% of Unpaid Principal Balance	1.90%	2.20%
Residential Portfolio Segment \| Foreclosure
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Outstanding balance past due	$ 312,619	$ 297,509
% of Unpaid Principal Balance	2.70%	2.40%
Residential Portfolio Segment \| REO
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Outstanding balance past due	$ 26,341	$ 29,852
% of Unpaid Principal Balance	0.20%	0.20%
Residential Portfolio Segment \| 30 Days Delinquent
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Outstanding balance past due	$ 593,685	$ 727,012
% of Unpaid Principal Balance	5.20%	5.80%
Residential Portfolio Segment \| 60 Days Delinquent
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Outstanding balance past due	$ 180,788	$ 289,966
% of Unpaid Principal Balance	1.60%	2.30%
Residential Portfolio Segment \| 90+ Days Delinquent
Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]
Outstanding balance past due	$ 527,805	$ 729,713
% of Unpaid Principal Balance	4.60%	5.80%

Financing Receivable, Recorded Investment, Past Due, Percent Of Total Amount Outstanding

No definition available.

Name:	cim_FinancingReceivableRecordedInvestmentPastDuePercentOfTotalAmountOutstanding
Namespace Prefix:	cim_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Securitized Loans Held For Investment By Consolidated Variable Interest Entities [Line Items]

+ References

No definition available.

+ Details

Name:	cim_SecuritizedLoansHeldForInvestmentByConsolidatedVariableInterestEntitiesLineItems
Namespace Prefix:	cim_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Securitized Residential Mortgage Loans Principal Amount Outstanding

+ References

No definition available.

+ Details

Name:	cim_SecuritizedResidentialMortgageLoansPrincipalAmountOutstanding
Namespace Prefix:	cim_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount excluding accrued interest, before allowance for credit loss, of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 3B
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL120267963-210447

+ Details

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

- Definition

Amount of undisbursed portion of financing receivable balance. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5066-111524

+ Details

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

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=cim_SeasonedSubprimeResidentialMortgageLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=cim_LoansHeldForInvestmentAtFairValueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=cim_BankruptcyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=cim_ForeclosureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=cim_RealEstateOwnedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables30To59DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables60To89DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: