Statement of Shareholders' Equity (Statement) - USD ($) $ in Thousands	Total	Additional Paid-in Capital [Member]	Common Stock [Member]	Retained Earnings	Noncontrolling Interest
Statement of Stockholders' Equity [Abstract]
Additional Paid in Capital	$ 290,799
Treasury Stock, Value	$ 3,167
Treasury Stock, Common, Shares	391,939
Common Stock, Shares, Issued	50,879,949
Common stock, $0.01 par value: 100,000,000 shares authorized; 51,124,215 and 51,053,858 issued and 50,732,276 and 50,661,919 outstanding as of March 31, 2021 and December 31, 2020, respectively	$ 509
Treasury Stock, Value	$ 3,167
Common Stock, Shares, Issued	50,879,949
Common stock, $0.01 par value: 100,000,000 shares authorized; 51,124,215 and 51,053,858 issued and 50,732,276 and 50,661,919 outstanding as of March 31, 2021 and December 31, 2020, respectively	$ 509
Treasury Stock, Common, Shares	391,939
Additional Paid in Capital	$ 290,799
Retained Earnings (Accumulated Deficit)	235,027
Stockholders' Equity Attributable to Parent	523,168
Stockholders' Equity Attributable to Noncontrolling Interest	13,227
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 536,395
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture	204,620
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	$ 1,600	$ 1,598	$ 2
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	$ 592	(591)	(1)
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation	75,708
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	$ 134
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	2,970
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest					$ 243
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	16,160
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	592	(591)	(1)
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	$ 1,600	1,598	2
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture	204,620
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation	75,708
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	$ 134
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	2,970
Net income attributable to Green Brick Partners, Inc.	15,917			$ 15,917
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest					243
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	16,160
Noncontrolling Interest, Increase from Business Combination	400
Noncontrolling Interest, Change in Redemption Value	2,755	2,755
Additional Paid in Capital		294,695
Treasury Stock, Value	$ 3,167
Treasury Stock, Common, Shares	391,939
Common Stock, Shares, Issued	51,008,861
Common stock, $0.01 par value: 100,000,000 shares authorized; 51,124,215 and 51,053,858 issued and 50,732,276 and 50,661,919 outstanding as of March 31, 2021 and December 31, 2020, respectively			510
Treasury Stock, Value	$ 3,167
Common Stock, Shares, Issued	51,008,861
Common stock, $0.01 par value: 100,000,000 shares authorized; 51,124,215 and 51,053,858 issued and 50,732,276 and 50,661,919 outstanding as of March 31, 2021 and December 31, 2020, respectively			510
Treasury Stock, Common, Shares	391,939
Additional Paid in Capital		294,695
Retained Earnings (Accumulated Deficit)	$ 250,944
Stockholders' Equity Attributable to Parent	542,982
Stockholders' Equity Attributable to Noncontrolling Interest	10,900
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	553,882
Additional Paid in Capital	293,242
Treasury Stock, Value	$ 3,167
Treasury Stock, Common, Shares	391,939
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	500,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 7.49
Common Stock, Shares, Issued	51,053,858
Common stock, $0.01 par value: 100,000,000 shares authorized; 51,124,215 and 51,053,858 issued and 50,732,276 and 50,661,919 outstanding as of March 31, 2021 and December 31, 2020, respectively	$ 511
Additional Paid in Capital, Common Stock	293,242
Treasury Stock, Value	$ 3,167
Common Stock, Shares, Issued	51,053,858
Common stock, $0.01 par value: 100,000,000 shares authorized; 51,124,215 and 51,053,858 issued and 50,732,276 and 50,661,919 outstanding as of March 31, 2021 and December 31, 2020, respectively	$ 511
Treasury Stock, Common, Shares	391,939
Additional Paid in Capital	$ 293,242
Retained Earnings (Accumulated Deficit)	349,656
Stockholders' Equity Attributable to Parent	640,242
Stockholders' Equity Attributable to Noncontrolling Interest	9,167
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 649,409
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	3 years 6 months 29 days
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture	111,675
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	$ 2,437	2,436	1
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	$ 834	833	(1)
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation	41,318
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	$ 146
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest					1,463
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	$ 27,432
Granted (in shares)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period	0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	3 years 6 months 29 days
Share-based Payment Arrangement, Decrease for Tax Withholding Obligation	$ 834	833	(1)
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	$ 2,437	2,436	$ 1
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture	111,675
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation	41,318
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	$ 146
Net income attributable to Green Brick Partners, Inc.	25,969			$ 25,969
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest					$ 1,463
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	27,432
Noncontrolling Interest, Change in Redemption Value	(1,829)	$ (1,829)
Additional Paid in Capital	293,162
Treasury Stock, Value	$ 3,167
Treasury Stock, Common, Shares	391,939
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	500,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 7.49
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 7,595
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	500,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 7.49
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 7,595
Common Stock, Shares, Issued	51,124,215
Common stock, $0.01 par value: 100,000,000 shares authorized; 51,124,215 and 51,053,858 issued and 50,732,276 and 50,661,919 outstanding as of March 31, 2021 and December 31, 2020, respectively	$ 511
Additional Paid in Capital, Common Stock	293,162
Treasury Stock, Value	$ 3,167
Common Stock, Shares, Issued	51,124,215
Common stock, $0.01 par value: 100,000,000 shares authorized; 51,124,215 and 51,053,858 issued and 50,732,276 and 50,661,919 outstanding as of March 31, 2021 and December 31, 2020, respectively	$ 511
Treasury Stock, Common, Shares	391,939
Additional Paid in Capital	$ 293,162
Retained Earnings (Accumulated Deficit)	375,625
Stockholders' Equity Attributable to Parent	666,131
Stockholders' Equity Attributable to Noncontrolling Interest	10,630
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 676,761