COVER PAGE - USD ($)	12 Months Ended
	Dec. 31, 2020	Jan. 31, 2021	Jun. 30, 2020
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Current Fiscal Year End Date	--12-31
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	1-33796
Entity Registrant Name	CHIMERA INVESTMENT CORP
Entity Incorporation, State or Country Code	MD
Entity Tax Identification Number	26-0630461
Entity Address, Address Line One	520 Madison Avenue, 32nd Floor
Entity Address, City or Town	New York,
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10022
City Area Code	888
Local Phone Number	895-6557
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 2,192,560,401
Entity Common Stock, Shares Outstanding (in shares)		230,559,010
Documents Incorporated by Reference	Portions of the registrant’s definitive Proxy Statement for the 2020 Annual Meeting of Stockholders, which will be filed with the Securities and Exchange Commission under Regulation 14A within 120 days after the end of registrant’s fiscal year covered by this Annual Report, are incorporated by reference into Part III.
Entity Central Index Key	0001409493
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Amendment Flag	false
Common Stock
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	CIM
Security Exchange Name	NYSE
Series A Preferred Stock
Entity Information [Line Items]
Title of 12(b) Security	8.00% Series A Cumulative Redeemable Preferred Stock
Trading Symbol	CIM PRA
Security Exchange Name	NYSE
Series B Preferred Stock
Entity Information [Line Items]
Title of 12(b) Security	8.00% Series B Cumulative Fixed-to-Floating Rate Redeemable Preferred Stock
Trading Symbol	CIM PRB
Security Exchange Name	NYSE
Series C Preferred Stock
Entity Information [Line Items]
Title of 12(b) Security	7.75% Series C Cumulative Fixed-to-Floating Rate Redeemable Preferred Stock
Trading Symbol	CIM PRC
Security Exchange Name	NYSE
Series D Preferred Stock
Entity Information [Line Items]
Title of 12(b) Security	8.00% Series D Cumulative Fixed-to-Floating Rate Redeemable Preferred Stock
Trading Symbol	CIM PRD
Security Exchange Name	NYSE