Revenue from Contracts with Customers - Disaggregated Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue [Line Items]
Total revenue	$ 170,822	$ 203,457	$ 342,143	$ 401,887
Transferred overtime
Disaggregation of Revenue [Line Items]
Total revenue	104,968	128,987	196,115	249,526
Transferred at point in time
Disaggregation of Revenue [Line Items]
Total revenue	65,854	74,470	146,028	152,361
ESS
Disaggregation of Revenue [Line Items]
Total revenue	97,660	125,547	198,350	233,088
ESS \| Transferred overtime
Disaggregation of Revenue [Line Items]
Total revenue	65,013	89,340	125,033	162,326
ESS \| Transferred at point in time
Disaggregation of Revenue [Line Items]
Total revenue	32,647	36,207	73,317	70,762
PCS
Disaggregation of Revenue [Line Items]
Total revenue	73,162	77,910	143,793	168,799
PCS \| Transferred overtime
Disaggregation of Revenue [Line Items]
Total revenue	39,955	39,647	71,082	87,200
PCS \| Transferred at point in time
Disaggregation of Revenue [Line Items]
Total revenue	33,207	38,263	72,711	81,599
Project and other manufacturing contracts revenue
Disaggregation of Revenue [Line Items]
Total revenue	10,093	33,139	22,385	57,756
Project and other manufacturing contracts revenue \| ESS
Disaggregation of Revenue [Line Items]
Total revenue	5,395	29,102	14,416	48,276
Project and other manufacturing contracts revenue \| PCS
Disaggregation of Revenue [Line Items]
Total revenue	4,698	4,037	7,969	9,480
Sale of products
Disaggregation of Revenue [Line Items]
Total revenue	10,494	25,835	30,995	55,966
Sale of products \| ESS
Disaggregation of Revenue [Line Items]
Total revenue	7,508	12,986	15,651	29,923
Sale of products \| PCS
Disaggregation of Revenue [Line Items]
Total revenue	2,986	12,849	15,344	26,043
Product revenue
Disaggregation of Revenue [Line Items]
Total revenue	20,587	58,974	53,380	113,722
Product revenue \| ESS
Disaggregation of Revenue [Line Items]
Total revenue	12,903	42,088	30,067	78,199
Product revenue \| PCS
Disaggregation of Revenue [Line Items]
Total revenue	7,684	16,886	23,313	35,523
Service revenue
Disaggregation of Revenue [Line Items]
Total revenue	89,072	92,332	161,081	175,840
Service revenue \| ESS
Disaggregation of Revenue [Line Items]
Total revenue	53,815	56,722	97,968	98,120
Service revenue \| PCS
Disaggregation of Revenue [Line Items]
Total revenue	35,257	35,610	63,113	77,720
Spare parts revenue
Disaggregation of Revenue [Line Items]
Total revenue	61,163	52,151	127,682	112,325
Spare parts revenue \| ESS
Disaggregation of Revenue [Line Items]
Total revenue	30,942	26,737	70,315	56,769
Spare parts revenue \| PCS
Disaggregation of Revenue [Line Items]
Total revenue	$ 30,221	$ 25,414	$ 57,367	$ 55,556