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NOTES PAYABLE AND LEASE OBLIGATIONS - Additional Information (Details) $ in Millions, ¥ in Billions		3 Months Ended	6 Months Ended
	Apr. 12, 2019 JPY (¥)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 JPY (¥)
Debt Instrument [Line Items]
Operating lease, cost		$ 14	$ 29
Operating lease, payments			28
Lines of credit
Debt Instrument [Line Items]
Debt instrument, debt default, amount		$ 0	$ 0
.963% perpetual subordinated bonds callable April 2024
Debt Instrument [Line Items]
Debt instrument, principal amount \| ¥	¥ 30.0			¥ 30.0
Debt instrument, description of variable rate basis	These bonds bear interest at a fixed rate of .963% per annum and then at six-month Euro Yen LIBOR plus an applicable spread on and after the day immediately following April 18, 2024.
Debt instrument, interest rate	0.963%	0.963%	0.963%	0.963%
Notes payable
Debt Instrument [Line Items]
Debt instrument, debt default, amount		$ 0	$ 0