Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ 1	$ 5

Income Tax Expense (Benefit), Excluding Real Estate Tax Expenses

No definition available.

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Namespace Prefix:	cim_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration