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FINANCIAL DERIVATIVES AND HEDGING ACTIVITIES - Outstanding Derivatives Used to Hedge Foreign Exchange Risks (Details) ₱ in Thousands, € in Thousands, ¥ in Thousands, £ in Thousands, SFr in Thousands, $ in Thousands	Mar. 31, 2024 EUR (€)	Mar. 31, 2024 PHP (₱)	Mar. 31, 2024 USD ($)	Mar. 31, 2024 GBP (£)	Mar. 31, 2024 JPY (¥)	Mar. 31, 2024 CHF (SFr)	Dec. 31, 2023 EUR (€)	Dec. 31, 2023 PHP (₱)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 GBP (£)	Dec. 31, 2023 JPY (¥)	Dec. 31, 2023 CHF (SFr)
U.S. Dollar / British Pound | Not Designated as Hedging | Sell/Buy - sell notional
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative notional amount			$ 22,000						$ 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 | €	€ 11,500						€ 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 | €	8,700						10,200
British Pound / Euro | Not Designated as Hedging | Sell/Buy - sell notional
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative notional amount | £				£ 3,560						£ 3,500
British Pound / Euro | Not Designated as Hedging | Sell/Buy - buy notional
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative notional amount | £				11,811						6,470
Japanese Yen / Euro | Not Designated as Hedging | Sell/Buy - sell notional
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative notional amount | ¥					¥ 47,920						¥ 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			14,942						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 | £				1,250						2,240
Euro / Swiss Franc | Not Designated as Hedging | Sell/Buy - sell notional
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative notional amount | €	4,732						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			7,760						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 990						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			3,120						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 | €	15,580						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 | ₱		₱ 19,962						₱ 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			14,030						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			344						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 | €	683,231						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 | £				947,687						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 | €	€ 80,444						€ 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			$ 32,892						$ 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 | £				£ 368						£ 2,211

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

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