Condensed Consolidated Statements of Stockholders' Equity and Contingently Redeemable Non-controlling Interest (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Total Great Elm Group Inc. Stockholders' Equity	Non-controlling Interest
Beginning balance at Jun. 30, 2020	$ 52,731	$ 26	$ 3,305,963	$ (3,257,144)	$ 48,845	$ 3,886
Beginning balance (in shares) at Jun. 30, 2020		25,530,000
Beginning balance, Contingently redeemable non-controlling interest at Jun. 30, 2020	3,890
Net loss	(3,655)			(3,594)	(3,594)	(61)
Net loss, Contingently redeemable non-controlling interest	(46)
Issuance of common stock related to vesting of restricted stock		$ 0
Issuance of common stock related to vesting of restricted stock (in shares)		116,000
Stock-based compensation	429		429		429
Ending balance at Sep. 30, 2020	49,505	$ 26	3,306,392	(3,260,738)	45,680	3,825
Ending balance (in shares) at Sep. 30, 2020		25,646,000
Ending balance, Contingently redeemable non-controlling interest at Sep. 30, 2020	3,844
Beginning balance at Jun. 30, 2020	52,731	$ 26	3,305,963	(3,257,144)	48,845	3,886
Beginning balance (in shares) at Jun. 30, 2020		25,530,000
Beginning balance, Contingently redeemable non-controlling interest at Jun. 30, 2020	3,890
Repurchases of interests in subsidiary	68
Ending balance at Mar. 31, 2021	53,412	$ 26	3,307,362	(3,263,512)	43,876	9,536
Ending balance (in shares) at Mar. 31, 2021		25,836,000
Ending balance, Contingently redeemable non-controlling interest at Mar. 31, 2021	2,055
Beginning balance at Sep. 30, 2020	49,505	$ 26	3,306,392	(3,260,738)	45,680	3,825
Beginning balance (in shares) at Sep. 30, 2020		25,646,000
Beginning balance, Contingently redeemable non-controlling interest at Sep. 30, 2020	3,844
Net loss	(492)			(187)	(187)	(305)
Net loss, Contingently redeemable non-controlling interest	(292)
Issuance of common stock related to vesting of restricted stock		$ 0
Issuance of common stock related to vesting of restricted stock (in shares)		45,000
Distributions to non-controlling interest holders of DME Inc.	(985)					(985)
Distributions to non-controlling interest holders of DME Inc., Contingently redeemable non-controlling interest	(985)
Issuance of Forest common stock	2,700					2,700
Stock-based compensation	285		285		285
Ending balance at Dec. 31, 2020	51,013	$ 26	3,306,677	(3,260,925)	45,778	5,235
Ending balance (in shares) at Dec. 31, 2020		25,691,000
Ending balance, Contingently redeemable non-controlling interest at Dec. 31, 2020	2,567
Net loss	(2,236)			(2,587)	(2,587)	351
Net loss, Contingently redeemable non-controlling interest	(509)
Repurchases of interests in subsidiary	145		(533)		(533)	678
Issuance of common stock related to vesting of restricted stock		$ 0
Issuance of common stock related to vesting of restricted stock (in shares)		146,000
Non-cash distributions to non-controlling interest holders of DME, Inc.	(3)					(3)
Non-cash distributions to non-controlling interest holders of DME, Inc., Contingently Redeemable Non-controlling Interest	(3)
Deemed capital contribution related to issuance of convertible notes	602		602		602
Issuance Of LP Interests In Consolidated Fund	3,275					3,275
Stock-based compensation	616		616		616
Ending balance at Mar. 31, 2021	53,412	$ 26	3,307,362	(3,263,512)	43,876	9,536
Ending balance (in shares) at Mar. 31, 2021		25,836,000
Ending balance, Contingently redeemable non-controlling interest at Mar. 31, 2021	2,055
Beginning balance at Jun. 30, 2021	$ 52,785	$ 26	3,307,613	(3,264,403)	43,236	9,549
Beginning balance (in shares) at Jun. 30, 2021	25,948,100	25,948,000
Beginning balance, Contingently redeemable non-controlling interest at Jun. 30, 2021	$ 2,639
Net loss	(99)			(200)	(200)	101
Net loss, Contingently redeemable non-controlling interest	205
Issuance of interests in Consolidated Funds, net	527					527
Issuance of common stock related to vesting of restricted stock		$ 0
Issuance of common stock related to vesting of restricted stock (in shares)		145,000
Stock-based compensation	581		581		581
Ending balance at Sep. 30, 2021	53,794	$ 26	3,308,194	(3,264,603)	43,617	10,177
Ending balance (in shares) at Sep. 30, 2021		26,093,000
Ending balance, Contingently redeemable non-controlling interest at Sep. 30, 2021	2,844
Beginning balance at Jun. 30, 2021	$ 52,785	$ 26	3,307,613	(3,264,403)	43,236	9,549
Beginning balance (in shares) at Jun. 30, 2021	25,948,100	25,948,000
Beginning balance, Contingently redeemable non-controlling interest at Jun. 30, 2021	$ 2,639
Repurchases of interests in subsidiary	43
Ending balance at Mar. 31, 2022	$ 44,718	$ 27	3,309,704	(3,274,750)	34,981	9,737
Ending balance (in shares) at Mar. 31, 2022	26,963,203	26,963,000
Ending balance, Contingently redeemable non-controlling interest at Mar. 31, 2022	$ 2,262
Beginning balance at Sep. 30, 2021	53,794	$ 26	3,308,194	(3,264,603)	43,617	10,177
Beginning balance (in shares) at Sep. 30, 2021		26,093,000
Beginning balance, Contingently redeemable non-controlling interest at Sep. 30, 2021	2,844
Net loss	(4,262)			(4,238)	(4,238)	(24)
Net loss, Contingently redeemable non-controlling interest	104
Redemption of interests in Consolidated Funds, net	(962)					(962)
Issuance of common stock related to vesting of restricted stock	1	$ 1			1
Issuance of common stock related to vesting of restricted stock (in shares)		722,000
Stock-based compensation	1,131		1,131		1,131
Ending balance at Dec. 31, 2021	49,702	$ 27	3,309,325	(3,268,841)	40,511	9,191
Ending balance (in shares) at Dec. 31, 2021		26,815,000
Ending balance, Contingently redeemable non-controlling interest at Dec. 31, 2021	2,948
Net loss	(5,449)			(5,909)	(5,909)	460
Net loss, Contingently redeemable non-controlling interest	(686)
Repurchases of interests in subsidiary	(43)		(129)		(129)	86
Issuance of common stock related to vesting of restricted stock		$ 0
Issuance of common stock related to vesting of restricted stock (in shares)		148,000
Stock-based compensation	508		508		508
Ending balance at Mar. 31, 2022	$ 44,718	$ 27	$ 3,309,704	$ (3,274,750)	$ 34,981	$ 9,737
Ending balance (in shares) at Mar. 31, 2022	26,963,203	26,963,000
Ending balance, Contingently redeemable non-controlling interest at Mar. 31, 2022	$ 2,262