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RELATED PARTY TRANSACTIONS (NARRATIVE) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Accounts Payable, Current	$ 84,180	$ 96,577
Revenue from Contract with Customer, Excluding Assessed Tax	2,207,587	2,462,817	$ 2,443,707
Affiliated Entity [Member] \| Avion and Airmax [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Purchases from Related Party	600	1,000	500
Accounts Payable, Current	36
Affiliated Entity [Member] \| Welltok
Related Party Transaction [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax			$ 500
Affiliated Entity [Member] \| Willis Towers Watson [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Purchases from Related Party	$ 2,800	$ 3,800
Chief Executive Officer [Member] \| Avion and Airmax [Member] \| Avion and Airmax [Member]
Related Party Transaction [Line Items]
Equity Method Investment, Ownership Percentage	100.00%