Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Treasury Stock	Common Stock [Member]	Capital Contributed in Excess of Par Value [Member]	Non-Controlling Interest In Partnerships [Member]	Accumulated Deficit [Member]	Total
BALANCES at Sep. 24, 2019		$ 13	$ 57,936	$ 1,522	$ (30,551)	$ 28,920
BALANCES, shares at Sep. 24, 2019		12,541,082
Stock-based compensation cost			74			74
Stock option exercises, shares		2,413
Restricted stock unit vesting
Restricted stock unit vesting, shares		76,643
Treasury shares purchased	$ (75)					(75)
Treasury shares purchased, shares	43,110	(43,110)
Non-controlling interests:
Income				212		212
Contributions				22		22
Distributions				(291)		(291)
Net Income (Loss) attributable to Good Times Restaurants Inc and comprehensive loss					(811)	(811)
BALANCES at Dec. 31, 2019	$ (75)	$ 13	58,010	1,465	(31,362)	28,051
BALANCES, shares at Dec. 31, 2019	43,110	12,577,028
Stock-based compensation cost			75			75
Restricted stock unit vesting
Restricted stock unit vesting, shares		14,000
Non-controlling interests:
Income				174		174
Distributions				(95)		(95)
Net Income (Loss) attributable to Good Times Restaurants Inc and comprehensive loss					(14,916)	(14,916)
BALANCES at Mar. 31, 2020	$ (75)	$ 13	58,085	1,544	(46,278)	13,289
BALANCES, shares at Mar. 31, 2020	43,110	12,591,028
Stock-based compensation cost			74			74
Restricted stock unit vesting
Restricted stock unit vesting, shares		4,626
Non-controlling interests:
Income				352		352
Distributions				(494)		(494)
Net Income (Loss) attributable to Good Times Restaurants Inc and comprehensive loss					289	289
BALANCES at Jun. 30, 2020	$ (75)	$ 13	58,159	1,402	(45,989)	13,510
BALANCES, shares at Jun. 30, 2020	43,110	12,595,654
BALANCES at Sep. 29, 2020	$ (75)	$ 13	58,219	1,293	(44,467)	14,983
BALANCES, shares at Sep. 29, 2020	43,110	12,612,852
Stock-based compensation cost			61			61
Stock option exercises			13			13
Stock option exercises, shares		7,984
Restricted stock unit vesting
Restricted stock unit vesting, shares		16,548
Non-controlling interests:
Income				363		363
Distributions				(319)		(319)
Net Income (Loss) attributable to Good Times Restaurants Inc and comprehensive loss					802	802
BALANCES at Dec. 29, 2020	$ (75)	$ 13	58,293	1,337	(43,665)	15,903
BALANCES, shares at Dec. 29, 2020	43,110	12,637,384
BALANCES at Sep. 29, 2020	$ (75)	$ 13	58,219	1,293	(44,467)	$ 14,983
BALANCES, shares at Sep. 29, 2020	43,110	12,612,852
Stock option exercises, shares						170,248
Non-controlling interests:
Income						$ 1,313
Contributions						14
Distributions						(1,472)
Net Income (Loss) attributable to Good Times Restaurants Inc and comprehensive loss						15,533
BALANCES at Jun. 29, 2021	$ (75)	$ 13	58,953	1,148	(28,934)	31,105
BALANCES, shares at Jun. 29, 2021	43,110	12,830,879
BALANCES at Dec. 29, 2020	$ (75)	$ 13	58,293	1,337	(43,665)	15,903
BALANCES, shares at Dec. 29, 2020	43,110	12,637,384
Stock-based compensation cost			215			215
Common stock granted, shares		12,948
Performance shares granted, shares		10,000
Stock option exercises			83			83
Stock option exercises, shares		35,346
Non-controlling interests:
Income				426		426
Distributions				(536)		(536)
Net Income (Loss) attributable to Good Times Restaurants Inc and comprehensive loss					1,097	1,097
BALANCES at Mar. 30, 2021	$ (75)	$ 13	58,591	1,227	(42,568)	17,188
BALANCES, shares at Mar. 30, 2021	43,110	12,695,678
Stock-based compensation cost			51			51
Stock option exercises			311			311
Stock option exercises, shares		126,918
Restricted stock unit vesting
Restricted stock unit vesting, shares		8,283
Non-controlling interests:
Income				524		524
Contributions				14		14
Distributions				(617)		(617)
Net Income (Loss) attributable to Good Times Restaurants Inc and comprehensive loss					13,634	13,634
BALANCES at Jun. 29, 2021	$ (75)	$ 13	$ 58,953	$ 1,148	$ (28,934)	$ 31,105
BALANCES, shares at Jun. 29, 2021	43,110	12,830,879