Stockholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Common Stock, Shares, Issued	50,879,949	50,719,884	50,879,949	50,719,884	50,820,548	50,719,884	50,685,699	50,598,901
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)			50,583,128
Beginning balance	$ 485,657	$ 439,068	$ 485,632	$ 433,038
Ending balance (in shares)	50,696,011		50,696,011
Ending balance	$ 498,643	455,532	$ 498,643	455,532
Common stock, $0.01 par value: 100,000,000 shares authorized; 50,879,949 and 50,719,884 issued and 50,696,011 and 50,583,128 outstanding as of June 30, 2019 and December 31, 2018, respectively	$ 509	$ 507	$ 509	$ 507	$ 508	$ 507	$ 507	$ 506
Treasury Stock, Common, Shares	(183,938)	0	(183,938)	0	(144,618)	(136,756)	0	0
Treasury Stock, Value	$ (1,369)	$ 0	$ (1,369)	$ 0	$ (1,041)	$ (981)	$ 0	$ 0
Additional Paid in Capital	289,739	290,842	289,739	290,842	291,271	291,299	290,773	289,938
Retained Earnings (Accumulated Deficit)	204,591	151,975	204,591	151,975	190,131	177,526	137,106	125,903
Stockholders' Equity Attributable to Parent	493,470	443,324	493,470	443,324	480,869	468,351	428,386	416,347
APIC, Share-based Payment Arrangement, Option, Increase for Cost Recognition	$ 71	$ 72	$ 142	$ 143
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture	59,401	34,185	219,181	140,211
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	$ 1	$ 0	$ 1,467	$ 1,081
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			(59,116)	(39,228)
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation			$ (545)	$ (412)
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	$ 117	101	$ 218	$ 197
Treasury Stock, Shares, Acquired	(39,320)		(47,182)	0
Treasury Stock, Value, Acquired, Cost Method	$ (328)		$ (388)	$ 0
Stockholders' Equity Attributable to Noncontrolling Interest	5,173	12,208	5,173	12,208	$ 4,788	$ 17,281	$ 10,682	$ 16,691
Payments to Noncontrolling Interests			10,993	10,423
Stock Issued During Period, Value, Acquisitions			0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(258)	(2,378)	(10,993)	(10,423)
Net income attributable to Green Brick Partners, Inc.	14,460	14,869	27,065	26,072
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest	643	3,904	(1,115)	5,940
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	15,103	18,773	25,950	32,012
Common Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	1	0	3	1
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation			1	0
Additional Paid-in Capital [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	0	0	1,464	1,080
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation			(544)	412
Temporary Equity, Accretion to Redemption Value, Adjustment	$ (1,720)	$ (104)	$ (2,840)	$ (104)