COMMITMENTS AND CONTINGENT LIABILITIES - Additional Information (Details) $ in Millions, ¥ in Billions	3 Months Ended
	Sep. 30, 2021 JPY (¥)	Sep. 30, 2021 USD ($)	Mar. 31, 2017 USD ($)
Commitments and Contingencies Disclosure [Line Items]
Loss contingency accrual, insurance-related assessment, discount rate			4.25%
Loss contingency, discounted amount of insurance-related assessment liability			$ 62
Loss contingency, undiscounted amount of insurance-related assessment liability			94
Loss contingency, insurance-related assessment, discounted amount of premium tax offset			48
Loss contingency, insurance-related assessment, undiscounted amount of premium tax offset			74
Loss contingency, loss in period			$ 14
Mainframe and server computer operations and support
Commitments and Contingencies Disclosure [Line Items]
Outsourcing agreement, remaining term	4 years	4 years
Outsourcing agreement, aggregate remaining cost	¥ 29.3	$ 262
Management consulting and technology services company application maintenance and development services
Commitments and Contingencies Disclosure [Line Items]
Outsourcing agreement, remaining term	6 years	6 years
Outsourcing agreement, aggregate remaining cost	¥ 16.9	$ 151
Enterprise software licensing agreement
Commitments and Contingencies Disclosure [Line Items]
Outsourcing agreement, remaining term	3 years	3 years
Outsourcing agreement, aggregate remaining cost	¥ 1.8	$ 16