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Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) $ in Thousands |  | 12 Months Ended
--- | --- | ---
May 29, 2020 USD ($) | Dec. 31, 2022 USD ($) facility segment component | Dec. 31, 2021 USD ($) segment | Dec. 31, 2020 USD ($)
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Number of reportable segments | segment |  | 2 | 3 |
Number of large, heavy components supplied to worldwide (more than) | component |  | 1,300 |  |
Research and development activities |  | $ 45,400 | $ 31,400 | $ 40,800
Research and development activities, paid by customers |  | 35,900 | 20,300 | 26,600
Interest expense |  | 53,900 | 51,100 | 40,800
Interest costs capitalized |  | 17,500 | 15,300 | 9,800
Restricted cash and cash equivalents reclassified into other assets |  | 5,700 |  |
Restricted cash and cash equivalents |  | 2,928 | 2,896 |
Total inventories |  | 22,900 | 16,300 |
Depreciation |  | 61,300 | 58,100 | 50,300
Lease expense |  | 8,600 | 8,400 | 7,700
Cash payments for leases |  | $ 6,600 |  |
Weighted average remaining lease term |  | 13 years 10 months 24 days |  |
Weighted average discount rate |  | 4.72% |  |
Asset retirement costs, estimated maximum duration |  | 40 years |  |
Number of facilities with U.S. Government decommissioning costs obligation | facility |  | 2 |  |
Reserves for self-insurance |  | $ 4,200 | 4,500 |
Net foreign currency transaction gains (losses) |  | (1,400) | 1,800 | (600)
Net gains deferred on derivative financial instruments in accumulated other comprehensive income (loss) |  | 100 |  |
Gain (loss) on foreign currency derivative instruments not designated as hedging instruments |  | (27,100) | (100) | 8,700
Notional amount of foreign currency forward contracts |  | 438,800 |  |
Favorable operating lease |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Amortization |  | 1,600 |  |
Nuclear Services Business |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Net assets exchanged in noncash transaction | $ 18,000 |  |  |
Accounts Receivable |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Canada Emergency Wage Subsidy (CEWS) grant |  | $ 600 | $ 5,400 | $ 20,400
Minimum |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Operating lease contract term (in years) |  | 1 year |  |
Operating lease renewal contract term (in years) |  | 1 year |  |
Minimum | Machinery and equipment |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Useful life (in years) |  | 3 years |  |
Minimum | Property, Plant and Equipment |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Useful life (in years) |  | 8 years |  |
Maximum |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Operating lease contract term (in years) |  | 20 years |  |
Operating lease renewal contract term (in years) |  | 10 years |  |
Maximum | Machinery and equipment |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Useful life (in years) |  | 14 years |  |
Maximum | Property, Plant and Equipment |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Useful life (in years) |  | 40 years |  |
Cash Held For Decommissioning Of Facilities |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Restricted cash and cash equivalents |  | $ 2,800 |  |
Cash Held To Meet Reinsurance Reserve Requirements |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |
Restricted cash and cash equivalents |  | $ 2,900 |  |

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