The value of common shares authorized to be issued by an entity's charter and bylaws.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The value of remaining common shares authorized to be issued by an entity's charter and bylaws.

+ References

No definition available.

+ Details

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- Definition

The weighted average price per share for shares issued and sold under the program.

+ References

No definition available.

+ Details

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Namespace Prefix:	chmi_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of fee for stock issuance.

+ References

No definition available.

+ Details

Name:	chmi_StockIssuanceFee
Namespace Prefix:	chmi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481520/505-30-50-4

+ Details

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Period Type:	instant

- References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

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

- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
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-Topic 946
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-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
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Period Type:	duration

- Details

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- Details

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- Details

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Equity and Earnings per Common Share, Common Stock ATM Program, Common Stock and Preferred Stock Repurchase Program (Details) - USD ($)	1 Months Ended			3 Months Ended				6 Months Ended		12 Months Ended
	Aug. 31, 2024	Nov. 30, 2022	Aug. 31, 2018	Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Dec. 31, 2023	Sep. 30, 2019
Class of Stock Disclosures [Abstract]
Issuance of common stock, net of offering costs								$ 378,000	$ 12,541,000
Common Stock [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock (in shares)				207,856	0	3,414,173	1,005,846
Stock Repurchase Program [Abstract]
Share repurchase program, authorized amount												$ 10,000,000
Number of shares repurchased (in shares)				0				0		0
Common Stock [Member] \| Common Stock ATM Program [Member]
Class of Stock Disclosures [Abstract]
Common stock value authorized	$ 150,000,000	$ 150,000,000	$ 50,000,000
Common stock value remaining								$ 34,600,000
Issuance of common stock (in shares)				0				0		4,909,053
Weighted average price (in dollars per share)										$ 3
Issuance of common stock, net of offering costs										$ 14,700,000
Stock issuance fee										$ 293,000
Preferred Stock [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock (in shares)				0	0	0	0
Stock Repurchase Program [Abstract]
Share repurchase program, authorized amount											$ 50,000,000
Number of shares repurchased (in shares)				0				0		0