Investments in available-for-sale debt securities (Details 2) $ in Thousands	Jun. 30, 2022 USD ($)
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Fair Value
Fair value, Less than 12 months	$ 3,436	[1]
Fair value, 12 months or more	0	[1]
Fair value	3,436	[1]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss
Gross unrealized losses, Less than 12 months	(79)
Gross unrealized losses, 12 months or more	0
Gross unrealized losses	(79)
U.S. government
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Fair Value
Fair value, Less than 12 months	603	[1]
Fair value, 12 months or more	0	[1]
Fair value	603	[1]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss
Gross unrealized losses, Less than 12 months	(6)
Gross unrealized losses, 12 months or more	0
Gross unrealized losses	(6)
Corporate and other taxable bonds
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Fair Value
Fair value, Less than 12 months	2,241	[1]
Fair value, 12 months or more	0	[1]
Fair value	2,241	[1]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss
Gross unrealized losses, Less than 12 months	(30)
Gross unrealized losses, 12 months or more	0
Gross unrealized losses	(30)
Other
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Fair Value
Fair value, Less than 12 months	592	[1]
Fair value, 12 months or more	0	[1]
Fair value	592	[1]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss
Gross unrealized losses, Less than 12 months	(43)
Gross unrealized losses, 12 months or more	0
Gross unrealized losses	$ (43)

[1] The fair value of the Company's available-for-sale debt securities are determined based upon inputs, other than the quoted prices in active markets, that are observable either directly or indirectly, and are classified as level 2 fair value measurements.