DERIVATIVE INSTRUMENTS - Schedule of Derivative Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Derivative Fair Values on Consolidated Balance Sheet [Line Items]
Derivative asset fair value	$ 13,929	$ 3,116
Derivative liability fair value	$ 24,493	$ 20,617
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other liabilities	Other liabilities
Not Designated as Hedging Instruments
Derivative Fair Values on Consolidated Balance Sheet [Line Items]
Derivative asset fair value	$ 13,929	$ 3,116
Derivative liability fair value	24,493	20,617
Not Designated as Hedging Instruments \| Relating to investment portfolio: \| Foreign exchange forward contracts
Derivative Fair Values on Consolidated Balance Sheet [Line Items]
Derivative notional amount	151,002	184,187
Derivative asset fair value	1,710	13
Derivative liability fair value	14	1,463
Not Designated as Hedging Instruments \| Relating to underwriting portfolio: \| Foreign exchange forward contracts
Derivative Fair Values on Consolidated Balance Sheet [Line Items]
Derivative notional amount	1,288,186	1,258,836
Derivative asset fair value	12,219	3,103
Derivative liability fair value	20,193	13,524
Not Designated as Hedging Instruments \| Relating to underwriting portfolio: \| Other underwriting-related contracts
Derivative Fair Values on Consolidated Balance Sheet [Line Items]
Derivative notional amount	50,000	50,000
Derivative asset fair value	0	0
Derivative liability fair value	$ 4,286	$ 5,630

Indicates line item in statement of financial position that includes derivative asset.

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