Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

+ Details

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

- Definition

Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_DebtSecuritiesAvailableForSaleMeasurementInput
Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
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

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

- Details

Name:	us-gaap_FinancialInstrumentAxis=cim_NonAgencySeniorMortgageBackedSecuritiesAvailableForSaleMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	cim_CreditQualityIndicatorAxis=us-gaap_CreditQualityIndicatorUpdatedQuarterlyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_WeightedAverageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDefaultRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputLossSeverityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=cim_NonAgencySubordinatedMortgageBackedSecuritiesAvailableForSaleMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Mortgage-Backed Securities - Schedule of Significant Credit Quality Indicators (Details)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Investment Holdings [Line Items]
Amortized Cost	$ 4,590,403,000	$ 10,999,354,000
Non-Agency RMBS - Senior
Investment Holdings [Line Items]
Amortized Cost	165,966,737
Non-Agency RMBS - Senior \| Residential Mortgage-Backed Securities
Investment Holdings [Line Items]
Amortized Cost	$ 1,003,307,000	1,072,686,000
Non-Agency RMBS - Senior \| Credit Quality Indicator, Updated Quarterly \| Weighted Average \| Discount Rate
Investment Holdings [Line Items]
Significant Inputs	0.060
Non-Agency RMBS - Senior \| Credit Quality Indicator, Updated Quarterly \| Weighted Average \| CDR
Investment Holdings [Line Items]
Significant Inputs	0.031
Non-Agency RMBS - Senior \| Credit Quality Indicator, Updated Quarterly \| Weighted Average \| Loss Severity
Investment Holdings [Line Items]
Significant Inputs	0.508
Non-Agency RMBS - Subordinated
Investment Holdings [Line Items]
Amortized Cost	$ 55,410,172
Non-Agency RMBS - Subordinated \| Residential Mortgage-Backed Securities
Investment Holdings [Line Items]
Amortized Cost	$ 567,004,000	$ 553,594,000
Non-Agency RMBS - Subordinated \| Credit Quality Indicator, Updated Quarterly \| Weighted Average \| Discount Rate
Investment Holdings [Line Items]
Significant Inputs	0.075
Non-Agency RMBS - Subordinated \| Credit Quality Indicator, Updated Quarterly \| Weighted Average \| CDR
Investment Holdings [Line Items]
Significant Inputs	0.009
Non-Agency RMBS - Subordinated \| Credit Quality Indicator, Updated Quarterly \| Weighted Average \| Loss Severity
Investment Holdings [Line Items]
Significant Inputs	0.390