Segment Information, Nature of Operations, and Certain Concentrations - Additional Information (Detail)	12 Months Ended
Dec. 31, 2018 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	32
Senior Notes due 2022
Segment Reporting Information [Line Items]
Senior notes interest rate	3.95%
Homebuilding:
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 \| Homebuilding: \| District of Columbia
Segment Reporting Information [Line Items]
Revenue derived	30.00%
Geographic Concentration Risk \| Homebuilding: \| 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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- Definition

Number of Trade Names

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
-Topic 275
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Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

No definition available.

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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.

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No definition available.

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