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Summary of Significant Accounting Policies (Details) $ in Thousands			1 Months Ended		3 Months Ended			6 Months Ended		12 Months Ended
	Aug. 04, 2026	May 27, 2026 item	Oct. 31, 2025	Jul. 31, 2016	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) item segment	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)
Significant accounting policies
Number of reportable segments \| segment								1
Number of reporting unit \| item								1
Goodwill impairment loss						$ 0		$ 0	$ 0	$ 0
Cylinder deposit liability					$ 24,630	22,438		24,630		$ 22,438
Contract term			5 years	5 years
Renewal term		3 months	5 years	5 years
Number of renewal option \| item		2
Revenues					78,345		$ 72,849	138,496	128,192
Subsequent Events
Significant accounting policies
Renewal term	5 years
Federal
Significant accounting policies
Operating loss carryforwards					0			0
State
Significant accounting policies
Operating loss carryforwards					400			400
Management Service
Significant accounting policies
Revenues								$ 1,400	$ 1,200
Customer Concentration Risk \| United States Defense Logistics Agency \| Revenue from Contract with Customer
Significant accounting policies
Concentration risk percentage								10.00%	10.00%
Revenues								$ 15,800	$ 17,700
Customer Concentration Risk \| United States Defense Logistics Agency \| Accounts Receivable
Significant accounting policies
Concentration risk percentage								9.00%		23.00%
Accounts receivable					$ 4,100	$ 4,300		$ 4,100		$ 4,300
Customer Concentration Risk \| One Customer \| Accounts Receivable
Significant accounting policies
Concentration risk percentage								20.00%