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FINANCIAL DERIVATIVES AND HEDGING ACTIVITIES - Schedule of Outstanding Derivatives Used to Hedge Foreign Exchange Risks (Details) ₱ in Thousands, € in Thousands, ¥ in Thousands, £ in Thousands, SFr in Thousands, $ in Thousands | Sep. 30, 2024 EUR (€) | Sep. 30, 2024 PHP (₱) | Sep. 30, 2024 USD ($) | Sep. 30, 2024 GBP (£) | Sep. 30, 2024 JPY (¥) | Sep. 30, 2024 CHF (SFr) | Dec. 31, 2023 EUR (€) | Dec. 31, 2023 PHP (₱) | Dec. 31, 2023 USD ($) | Dec. 31, 2023 GBP (£) | Dec. 31, 2023 JPY (¥) | Dec. 31, 2023 CHF (SFr)
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U.S. Dollar / British Pound | Not Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  |  | $ 13,500 |  |  |  |  |  | $ 22,800 |  |  |
Euro / U.S. Dollar | Not Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | € | € 10,300 |  |  |  |  |  | € 11,000 |  |  |  |  |
Euro / U.S. Dollar | Not Designated as Hedging | Sell/Buy - buy notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | € | 0 |  |  |  |  |  | 10,200 |  |  |  |  |
British Pound / Euro | Not Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | £ |  |  |  | £ 2,600 |  |  |  |  |  | £ 3,500 |  |
British Pound / Euro | Not Designated as Hedging | Sell/Buy - buy notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | £ |  |  |  | 3,600 |  |  |  |  |  | 6,470 |  |
Japanese Yen / Euro | Not Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | ¥ |  |  |  |  | ¥ 53,000 |  |  |  |  |  | ¥ 0 |
U.S. Dollar / Swiss Franc | Not Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  |  | 0 |  |  |  |  |  | 13,620 |  |  |
British Pound / Swiss Franc | Not Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | £ |  |  |  | 930 |  |  |  |  |  | 2,240 |  |
Euro / Swiss Franc | Not Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | € | 8,200 |  |  |  |  |  | 4,940 |  |  |  |  |
U.S Dollar / Philippine Peso | Not Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  |  | 9,100 |  |  |  |  |  | 6,700 |  |  |
Swiss Franc / Danish Krone | Not Designated as Hedging | Sell/Buy - buy notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | SFr |  |  |  |  |  | SFr 0 |  |  |  |  |  | SFr 0
U.S. Dollar / Canadian Dollar | Not Designated as Hedging | Sell/Buy - buy notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  |  | 2,400 |  |  |  |  |  | 1,120 |  |  |
Cash Flow Hedges | Euro / British Pound | Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | € | 15,338 |  |  |  |  |  | 15,210 |  |  |  |  |
Cash Flow Hedges | Philippine Peso / Euro | Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | ₱ |  | ₱ 0 |  |  |  |  |  | ₱ 137,449 |  |  |  |
Cash Flow Hedges | U.S. Dollar / British Pound | Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  |  | 10,335 |  |  |  |  |  | 18,470 |  |  |
Cash Flow Hedges | U.S. Dollar / Euro | Designated as Hedging | Sell/Buy - sell notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  |  | 67 |  |  |  |  |  | 277 |  |  |
Cash Flow Hedges | Euro / Philippine Peso | Designated as Hedging | Sell/Buy - buy notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | € | 670,767 |  |  |  |  |  | 788,342 |  |  |  |  |
Cash Flow Hedges | British Pound / Philippine Peso | Designated as Hedging | Sell/Buy - buy notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | £ |  |  |  | 951,019 |  |  |  |  |  | 923,653 |  |
Cash Flow Hedges | Euro / U.S. Dollar | Designated as Hedging | Sell/Buy - buy notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | € | € 76,139 |  |  |  |  |  | € 93,397 |  |  |  |  |
Cash Flow Hedges | U.S. Dollar / Canadian Dollar | Designated as Hedging | Sell/Buy - buy notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount |  |  | $ 32,211 |  |  |  |  |  | $ 30,914 |  |  |
Cash Flow Hedges | British Pound / U.S. Dollar | Designated as Hedging | Sell/Buy - buy notional |  |  |  |  |  |  |  |  |  |  |  |
Derivative Instruments And Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative notional amount | £ |  |  |  | £ 0 |  |  |  |  |  | £ 2,211 |  |

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