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Related party transactions: (Details) $ in Thousands			1 Months Ended	12 Months Ended
	Jul. 25, 2023 USD ($) ft²	Apr. 01, 2023	May 31, 2015	Dec. 31, 2025 USD ($) ft²	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Amendment
Related party transactions
Area of land | ft²	7,369
Notice period for cancellation of lease	60 days
Operating lease income | $	$ 162,118
Amendment | Auditorium suitable for training
Related party transactions
Area of land | ft²	4,987
Amendment | Data center in building
Related party transactions
Area of land | ft²	2,382
Related party | Office Lease
Related party transactions
Payment made for rent and related costs | $				$ 3,200	$ 3,300	$ 2,800
Related party | Office Lease | Sodium LLC
Related party transactions
Fixed annual rent | $				$ 1,000
Lease term (in years)			5 years
Notice period for cancellation of lease			60 days
Related party | Office Lease | Thorium LLC
Related party transactions
Area of land | ft²				54,803
Lease term (in years)		5 years
Notice period for cancellation of lease		60 days
Operating lease income payments | $				$ 1,200
Operating Lease, Lease Income, Statement of Income or Comprehensive Income [Extensible Enumeration]				Operating Income (Loss)
Related party | Network Operations Lease | Germanium LLC
Related party transactions
Area of land | ft²				1,587
Lease term (in years)		5 years
Notice period for cancellation of lease		60 days
Operating lease income | $				$ 34,914

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