Significant Accounting Policies (Schedule of Basic and Diluted Net Income) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Basic net income attributable to Green Brick Partners, Inc. per share
Net income attributable to Green Brick Partners, Inc. —basic	$ 7,676	$ 6,243	$ 6,743	$ 3,094	$ 4,693	$ 2,826	$ 3,788	$ 4,018	$ 23,756	$ 15,325	$ 50,026
Weighted-average number of shares outstanding - basic (in shares)									48,879	40,068	14,712
Basic net income attributable to Green Brick Partners, Inc. per share (in dollars per share)	$ 0.16	$ 0.13	$ 0.14	$ 0.06	$ 0.10	$ 0.06	$ 0.12	$ 0.13	$ 0.49	$ 0.38	$ 3.40
Diluted net income attributable to Green Brick Partners, Inc. per share
Net income attributable to Green Brick Partners, Inc. —diluted									$ 23,756	$ 15,325	$ 50,026
Weighted-average number of shares outstanding - diluted (in shares)									48,886	40,099	14,712
Weighted Average Number Diluted Shares Outstanding Adjustment									7	30	0
Diluted net income attributable to Green Brick Partners, Inc. per share (in dollars per share)	$ 0.16	$ 0.13	$ 0.14	$ 0.06	$ 0.10	$ 0.06	$ 0.12	$ 0.13	$ 0.49	$ 0.38	$ 3.40