COMMITMENTS AND CONTINGENT LIABILITIES - Additional Information (Details) $ in Millions, ¥ in Billions	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2017 JPY (¥)	Jun. 30, 2017 USD ($)
Commitments And Contingencies Disclosure [Line Items]
Loss contingency accrual, insurance-related assessment, discount rate	4.25%		4.25%
Loss contingency, discounted amount of insurance-related assessment liability	$ 62		$ 62
Loss contingency, undiscounted amount of insurance-related assessment liability			94
Loss contingency, insurance-related assessment, discounted amount of premium tax offset	48		48
Loss contingency, insurance-related assessment, undiscounted amount of premium tax offset	$ 74		$ 74
Loss contingency, discounted amount of insurance-related assessment liability, payment period (in years)			1
Loss contingency, discounted amount of insurance-related assessment liability, realization period for associated asset offsets (in years)			5
Loss contingency, loss in period			$ 14
Information technology and data services company application maintenance and development services agreement
Commitments And Contingencies Disclosure [Line Items]
Outsourcing agreements, remaining term	5 years	5 years
Outsourcing agreements, aggregate remaining cost	$ 73	¥ 8.2