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Financial Derivatives and Hedging Activities - Outstanding Derivatives Used to Hedge Foreign Exchange Risks (Detail) | Sep. 30, 2022 EUR (€) | Sep. 30, 2022 USD ($) | Sep. 30, 2022 PHP (₱) | Sep. 30, 2022 CAD ($) | Sep. 30, 2022 GBP (£) | Dec. 31, 2021 EUR (€) | Dec. 31, 2021 USD ($) | Dec. 31, 2021 PHP (₱) | Dec. 31, 2021 CAD ($) | Dec. 31, 2021 GBP (£)
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Cash Flow Hedges | Euro / British Pound | Designated as Hedging | Sell Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount | € | € 22,203,000 |  |  |  |  | € 18,823,000 |  |  |  |
Cash Flow Hedges | U.S. Dollar / British Pound | Designated as Hedging | Sell Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  | $ 28,754,000 |  |  |  |  | $ 16,205,000 |  |  |
Cash Flow Hedges | U.S. Dollar / Euro | Designated as Hedging | Sell Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  | 1,911,000 |  |  |  |  | 658,000 |  |  |
Cash Flow Hedges | Euro / Philippine Peso | Designated as Hedging | Buy Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount | ₱ |  |  | ₱ 964,410,000 |  |  |  |  | ₱ 896,291,000 |  |
Cash Flow Hedges | British Pound / Philippine Peso | Designated as Hedging | Buy Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount | ₱ |  |  | ₱ 1,301,671,000 |  |  |  |  | ₱ 1,121,183,000 |  |
Cash Flow Hedges | Euro / U.S. Dollar | Designated as Hedging | Buy Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  | 96,822,000 |  |  |  |  | 108,467,000 |  |  |
Cash Flow Hedges | U.S. Dollar / Canadian Dollar | Designated as Hedging | Buy Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  |  |  | $ 36,649,000 |  |  |  |  | $ 36,904,000 |
Foreign Currency Hedges | U.S. Dollar / British Pound | Not Designated as Hedging | Sell Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  | 29,200,000 |  |  |  |  | 26,600,000 |  |  |
Foreign Currency Hedges | Euro / U.S. Dollar | Not Designated as Hedging | Sell Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount | € | 7,200,000 |  |  |  |  | 11,000,000 |  |  |  |
Foreign Currency Hedges | Euro / U.S. Dollar | Not Designated as Hedging | Buy Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  | 6,300,000 |  |  |  |  | 20,900,000 |  |  |
Foreign Currency Hedges | British Pound / Euro | Not Designated as Hedging | Sell Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount | £ |  |  |  |  | £ 3,200,000 |  |  |  |  | £ 3,400,000
Foreign Currency Hedges | British Pound / Euro | Not Designated as Hedging | Buy Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount | € | 17,800,000 |  |  |  |  | 5,300,000 |  |  |  |
Foreign Currency Hedges | U.S. Dollar / Swiss Franc | Not Designated as Hedging | Sell Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  | $ 430,000 |  |  |  |  | $ 2,180,000 |  |  |
Foreign Currency Hedges | British Pound / Swiss Franc | Not Designated as Hedging | Sell Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount | £ |  |  |  |  | £ 2,420,000 |  |  |  |  | £ 1,025,000
Foreign Currency Hedges | Euro / Swiss Franc | Not Designated as Hedging | Sell Notional |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |
Derivative notional amount | € | € 7,830,000 |  |  |  |  | € 2,750,000 |  |  |  |

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