Segment Information, Nature of Operations, and Certain Concentrations - Additional Information (Detail)	12 Months Ended
Dec. 31, 2020 Trade_Names metropolitan_area segment
Segment Reporting Information [Line Items]
Number of trade names \| Trade_Names	3
Number of metropolitan areas Ryan Homes product are sold \| metropolitan_area	33
Senior Notes due 2022
Segment Reporting Information [Line Items]
Senior notes interest rate	3.95%
Senior Notes Due Two Thousand Thirty [Member]
Segment Reporting Information [Line Items]
Senior notes interest rate	3.00%
Home Building
Segment Reporting Information [Line Items]
Number of reportable segments	4
Mortgage Banking
Segment Reporting Information [Line Items]
Number of reportable segments	1
Geographic Concentration Risk \| Home Building \| District of Columbia
Segment Reporting Information [Line Items]
Revenue derived	24.00%
Geographic Concentration Risk \| Home Building \| Maryland, Baltimore
Segment Reporting Information [Line Items]
Revenue derived	10.00%

The number of metropolitan areas that Ryan Homes products are sold in.

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Number of Trade Names

+ References

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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.

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