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Related Party Transactions - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
	Dec. 29, 2020	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2022	Mar. 31, 2021	Dec. 18, 2020
Related Party Transaction [Line Items]
Reorganization date				Dec. 21, 2020
Plan of reorganization, description of equity securities issued or to be issued				On December 29, 2020, pursuant to the terms of the Agreement and Plan of Merger, dated as of December 21, 2020, among Forest, the Company and Forest Merger Sub, Inc., a newly created entity for the purpose of facilitating the Merger, (as it may be amended from time to time, the Merger Agreement), the transactions contemplated by the Merger Agreement (the Transactions) were consummated. As a result of the Transactions, and subject to the same terms and conditions as applied immediately prior to the Transactions, each share of Forest's outstanding common stock, common stock options, restricted stock units and restricted shares were exchanged for identical instruments of the Company
Forest Merger Sub Inc \| J.P. Morgan Broker-Dealer Holdings Inc. (JPM)
Related Party Transaction [Line Items]
Total purchase consideration	$ 37,700
Forest Investments, Inc. (Forest)
Related Party Transaction [Line Items]
Proceeds from issuance of common stock					$ 2,700
Issuance of Forest preferred stock					35,010
Forest Investments, Inc. (Forest) \| Forest Preferred Stock Classified as Liability
Related Party Transaction [Line Items]
Redeemable preferred stock, shares	35,010
Redeemable preferred stock, annual dividend rate	9.00%
Redeemable Preferred stock, redemption price per share	$ 1,000.00
Redeemable Preferred stock, redemption date	Dec. 29, 2027
Redeemable preferred stock, face value per share	$ 1,000.00
Forest Investments, Inc. (Forest) \| J.P. Morgan Broker-Dealer Holdings Inc. (JPM)
Related Party Transaction [Line Items]
Percentage of equity interest acquired (as a percent)	20.00%
Business acquisition, common stock purchase price	$ 2,700
Business acquisition, annual consulting fees	450
Great Elm Healthcare, LLC (HC LLC)
Related Party Transaction [Line Items]
Reimbursement amount received to cover deal costs	$ 1,300
Great Elm Healthcare, LLC (HC LLC) \| Series A-1 Preferred Stock Classified as Liability
Related Party Transaction [Line Items]
Redeemable preferred stock, shares	10,090
Redeemable preferred stock, annual dividend rate	9.00%
Redeemable Preferred stock, redemption price per share	$ 1,000.00
Redeemable Preferred stock, redemption date	Dec. 29, 2027
Redeemable preferred stock, face value per share	$ 1,000.00
Great Elm Healthcare, LLC (HC LLC) \| Series A-2 Preferred Stock Classified as Liability
Related Party Transaction [Line Items]
Redeemable preferred stock, shares	34,010
Redeemable preferred stock, annual dividend rate	9.00%
Redeemable Preferred stock, redemption price per share	$ 1,000.00
Redeemable Preferred stock, redemption date	Dec. 29, 2027
Redeemable preferred stock, face value per share	$ 1,000.00
Percentage of proceeds arising from sale of durable medical equipment business	33.00%
DME, Inc.
Related Party Transaction [Line Items]
Cash	$ 1,900
MAST Capital
Related Party Transaction [Line Items]
Percentage of ownership interest issued to former owner/holder		7.30%		7.30%
MAST Capital \| Convertible Notes
Related Party Transaction [Line Items]
Issuance of notes payable				$ 2,300
Forest Investments, Inc. (Forest) \| Great Elm Healthcare, LLC (HC LLC) \| Series A-1 Preferred Stock Classified as Liability
Related Party Transaction [Line Items]
Preferred stock holding percentage	80.10%
Corbel \| Great Elm Healthcare, LLC (HC LLC) \| Series A-1 Preferred Stock Classified as Liability
Related Party Transaction [Line Items]
Preferred stock holding percentage	9.95%
Valley Healthcare Holdings, LLC (VHH) \| Great Elm Healthcare, LLC (HC LLC) \| Series A-1 Preferred Stock Classified as Liability
Related Party Transaction [Line Items]
Preferred stock holding percentage	9.95%
GECC
Related Party Transaction [Line Items]
Percentage of ownership interest (as a percent)		20.40%		20.40%
Value of ownership interest		$ 13,400		$ 13,400
Imperial Capital, LLC
Related Party Transaction [Line Items]
Retainer fee paid				$ 100
J.P. Morgan Broker-Dealer Holdings Inc. and JPMorgan Chase & Co \| Ligado Networks, LLC
Related Party Transaction [Line Items]
Business combination, common stock interest, percentage						21.00%
J.P. Morgan Broker-Dealer Holdings Inc. and JPMorgan Chase & Co \| Forest Merger Sub Inc
Related Party Transaction [Line Items]
Proceeds from issuance of common stock	$ 35,000
Issuance of Forest preferred stock	$ 2,700
Consolidated Fund
Related Party Transaction [Line Items]
Percentage of investment in consolidated fund had fair value of greater than of consolidated assets		5.00%		5.00%
Receivable for reimbursable expenses paid		$ 100		$ 100
Shared Personnel and Reimbursement Agreement \| Jason W. Reese \| Investment Management Expenses
Related Party Transaction [Line Items]
Costs incurred under agreement		$ 400	$ 100	$ 700	$ 200
Shared Personnel and Reimbursement Agreement \| Employee \| Restricted Stock Awards
Related Party Transaction [Line Items]
Restricted stock awards, grant date fair value			$ 200