Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jul. 23, 2015	Jul. 01, 2015
Class of Stock [Line Items]
Common Stock, Shares, Issued							17,000,000
Share Price							$ 10.00
AdditionalPurchaseOptionPeriod	30-day
CommonSharesGrantedToUnderwritersToCoverOver-Allotments							841,500
CommonSharesSoldPursuantToUnderwritersOption						444,897
Repayments of Secured Debt				$ 150,000	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (shares)				31,346,084
Beginning balance				$ 181,597	198,819
Share-based compensation				227
Issuance of common stock under 2014 Equity Plan				91
IssuanceOfCommonStockInConnectionWithEquityOfferingValue				169,983
Contributions				87	592
Distributions				(6,423)	(17,221)
Net income		$ 5,286	$ 6,063	$ 18,478	26,743
Ending balance (shares)		48,813,889		48,813,889
Ending balance		$ 364,040	208,933	$ 364,040	208,933
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				9,739	9,709
Contributions				87	592
Distributions				(6,423)	(11,439)
Net income				7,846	8,290
Ending balance		11,249	7,152	11,249	7,152
Total Green Brick Partners, Inc. Stockholders’ Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				171,858	189,110
Share-based compensation				227
Issuance of common stock under 2014 Equity Plan				91
IssuanceOfCommonStockInConnectionWithEquityOfferingValue				169,983
Distributions					(5,782)
Net income				10,632	18,453
Ending balance		$ 352,791	$ 201,781	$ 352,791	$ 201,781
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (shares)				31,346,084	11,108,500
Beginning balance				$ 313	$ 111
Issuance of common shares under 2014 Equity Plan (shares)				22,908
IssuanceOfCommonStockInConnectionEquityOfferingShare				17,444,897
IssuanceOfCommonStockInConnectionWithEquityOfferingValue				$ 175
Ending balance (shares)		48,813,889	11,108,500	48,813,889	11,108,500
Ending balance		$ 488	$ 111	$ 488	$ 111
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				101,626	155,985
Share-based compensation				227
Issuance of common stock under 2014 Equity Plan				91
IssuanceOfCommonStockInConnectionWithEquityOfferingValue				169,808
Ending balance		271,752	155,985	271,752	155,985
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance				69,919	33,014
Distributions					(5,782)
Net income				10,632	18,453
Ending balance		$ 80,551	$ 45,685	$ 80,551	$ 45,685