Business Combination, Consideration Transferred, Equity Interests Convertible, Ratio

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- Definition

Number Of Classes Of Stock

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- Definition

Number of Multifamily Apartment Communities

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- Definition

Number of Preferred Equity Investments

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- Definition

Number of persons employed by the Entity

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- Definition

The number of units in a real estate property owned as of the balance sheet date.

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- Definition

Cash received on stock transaction after deduction of issuance costs.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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- 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.

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Organization and Business (Details)				3 Months Ended
Organization and Business (Details)	May 07, 2021 realEstateUnit	Mar. 23, 2021 USD ($)	Nov. 08, 2019 USD ($) $ / shares	Mar. 31, 2021 USD ($) numberOfEmployee apartmentCommunity classesOfStock developmentProject $ / shares
Subsidiary, Sale of Stock [Line Items]
Number of employees \| numberOfEmployee				0
Value of shares in offering				$ 750,000,000
Number of classes of stock \| classesOfStock				2
Number of multifamily apartment communities \| apartmentCommunity				2
Number of preferred equity investment development projects \| developmentProject				3
Subsequent event \| CRII Merger \| Cottonwood Affiliates
Subsidiary, Sale of Stock [Line Items]
Units \| realEstateUnit	8,600
Subsequent event \| CRII Merger \| CRII Merger
Subsidiary, Sale of Stock [Line Items]
Units \| realEstateUnit	13,000
Subsequent event \| CROP
Subsidiary, Sale of Stock [Line Items]
Share conversion ratio	2.015
Subsequent event \| Class A \| CRII Merger
Subsidiary, Sale of Stock [Line Items]
Share conversion ratio	2.015
Subsequent event \| Series 2016 Preferred Stock \| CRII Merger
Subsidiary, Sale of Stock [Line Items]
Share conversion ratio	1
Subsequent event \| Series 2017 Preferred Stock \| CRII Merger
Subsidiary, Sale of Stock [Line Items]
Share conversion ratio	1
Subsequent event \| Series 2019 Preferred Stock \| CROP
Subsidiary, Sale of Stock [Line Items]
Share conversion ratio	1
Subsequent event \| LTIP Unit \| CROP
Subsidiary, Sale of Stock [Line Items]
Share conversion ratio	1
West Palm Beach
Subsidiary, Sale of Stock [Line Items]
Number of multifamily apartment communities \| apartmentCommunity				1
Greater Boston, Massachusetts
Subsidiary, Sale of Stock [Line Items]
Number of multifamily apartment communities \| apartmentCommunity				1
IPO
Subsidiary, Sale of Stock [Line Items]
Share price (in dollars per share) \| $ / shares				$ 10.00
Primary Offering
Subsidiary, Sale of Stock [Line Items]
Value of shares in offering				$ 675,000,000
Distribution Reinvestment Plan
Subsidiary, Sale of Stock [Line Items]
Value of shares in offering				$ 75,000,000
Share price (in dollars per share) \| $ / shares				$ 10.00
Private Placement \| 2019 Preferred Stock
Subsidiary, Sale of Stock [Line Items]
Value of shares in offering		$ 100,000,000	$ 50,000,000
Share price (in dollars per share) \| $ / shares			$ 10.00