Net Income Attributable to Green Brick Partners, Inc. Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Earnings Per Share [Abstract]
Net income attributable to Green Brick Partners, Inc. —basic	$ 9,280	$ 6,243	$ 23,165	$ 16,080
Weighted-average number of shares outstanding —basic (shares)	49,808	48,899	49,274	48,868
Weighted Average Number Diluted Shares Outstanding Adjustment (shares)	84	8	73	3
Basic net income attributable to Green Brick Partners, Inc. per share (usd per share)	$ 0.19	$ 0.13	$ 0.47	$ 0.33
Net income attributable to Green Brick Partners, Inc. —diluted	$ 9,280	$ 6,243	$ 23,165	$ 16,080
Weighted-average number of shares outstanding —diluted (shares)	49,892	48,907	49,347	48,871
Diluted net income attributable to Green Brick Partners, Inc. per share (usd per share)	$ 0.19	$ 0.13	$ 0.47	$ 0.33
Antidilutive options to purchase common stock (shares)	0	113	0	186