Discontinued operations - Assets and Liabilities of Discontinued Operations (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Apr. 17, 2024	Dec. 31, 2023
Discontinued Operations [Line Items]
Total current assets, discontinued operations	$ 0		$ 15,369
Total current liabilities, discontinued operations	$ 0		12,796
Discontinued Operations, Disposed of by Sale | Global Cooling
Discontinued Operations [Line Items]
Cash and cash equivalents		$ 275	2,090
Accounts receivable, net		2,430	1,728
Inventories		9,152	11,248
Prepaid expenses and other current assets		379	303
Total current assets, discontinued operations		12,236	15,369
Property and equipment, net		153	146
Long-term deposits and other assets		4	4
Total assets, discontinued operations		12,393	15,519
Accounts payable		1,425	3,367
Accrued expenses and other current liabilities		911	1,637
Warranty liability		7,193	7,507
Lease liabilities, operating, current portion		242	263
Lease liabilities, financing, current portion		16	22
Total current liabilities, discontinued operations		9,787	12,796
Lease liabilities, operating, long-term		948	1,016
Lease liabilities, financing, long-term		8	11
Total liabilities, discontinued operations		$ 10,743	$ 13,823