Net Income Attributable to Green Brick Partners, Inc. Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share [Abstract]
Net income attributable to Green Brick Partners, Inc.	$ 12,605	$ 11,203
Weighted-average number of shares outstanding —basic (in shares)	50,563	50,577
Basic net income attributable to Green Brick Partners, Inc. per share (in dollars per share)	$ 0.25	$ 0.22
Dilutive effect of stock options and restricted stock awards (in shares)	42	141
Weighted-average number of shares outstanding —diluted (in shares)	50,605	50,718
Diluted net income attributable to Green Brick Partners, Inc. per share (in dollars per share)	$ 0.25	$ 0.22