Quarterly report [Sections 13 or 15(d)]

INVESTMENT SECURITIES - Schedule of amortized cost, unrealized gains and losses accumulated in other comprehensive income, and fair value of available-for-sale securities (Details)

v3.25.4
INVESTMENT SECURITIES - Schedule of amortized cost, unrealized gains and losses accumulated in other comprehensive income, and fair value of available-for-sale securities (Details) - USD ($)
$ in Thousands
Dec. 31, 2025
Mar. 31, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Assets measured at amortized cost $ 517,276 $ 477,156
Accumulated impairment loss (435) (406)
Unrealized gain/(loss) accumulated in other comprehensive income/(loss) including foreign currency translation adjustments, net 4,702 (3,163)
Assets measured at fair value 521,543 473,587
Corporate debt    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Assets measured at amortized cost 324,120 243,660
Accumulated impairment loss 0 (28)
Unrealized gain/(loss) accumulated in other comprehensive income/(loss) including foreign currency translation adjustments, net 6,280 98
Assets measured at fair value 330,400 243,730
Non-US sovereign debt    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Assets measured at amortized cost 171,090 211,628
Accumulated impairment loss (435) (378)
Unrealized gain/(loss) accumulated in other comprehensive income/(loss) including foreign currency translation adjustments, net (1,567) (3,019)
Assets measured at fair value 169,088 208,231
U.S. sovereign debt    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Assets measured at amortized cost 22,066 21,868
Accumulated impairment loss 0 0
Unrealized gain/(loss) accumulated in other comprehensive income/(loss) including foreign currency translation adjustments, net (11) (242)
Assets measured at fair value $ 22,055 $ 21,626