Document And Entity Information	9 Months Ended
	Sep. 30, 2020 shares
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	GRBK
Security Exchange Name	NASDAQ
Document Transition Report	false
Document Quarterly Report	true
Entity Incorporation, State or Country Code	DE
Entity Registrant Name	Green Brick Partners, Inc.
Entity Central Index Key	0001373670
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Tax Identification Number	20-5952523
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Common Stock, Shares Outstanding	50,661,919
Entity Shell Company	false
Entity File Number	001-33530
Entity Address, Address Line One	2805 Dallas Pkwy
Entity Address, Address Line Two	Ste 400
Entity Address, City or Town	Plano
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75093
City Area Code	(469)
Local Phone Number	573-6755