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NOTES PAYABLE AND LEASE OBLIGATIONS - Additional Information (Details) $ in Millions, ¥ in Billions		1 Months Ended	3 Months Ended	9 Months Ended
	Apr. 12, 2019 JPY (¥)	Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2019 JPY (¥)	Dec. 31, 2018 JPY (¥)
Debt Instrument [Line Items]
Operating lease, cost \| $			$ 14	$ 43
Operating lease, payments \| $				42
Lines of credit
Debt Instrument [Line Items]
Debt instrument, debt default, amount \| $		$ 0	$ 0	$ 0
Yen-denominated loans
Debt Instrument [Line Items]
Debt instrument, principal amount \| ¥					¥ 30.0
Yen-denominated loan variable interest rate due September 2026
Debt Instrument [Line Items]
Debt instrument, principal amount \| ¥					¥ 5.0	¥ 5.0
Debt instrument, description of variable rate basis		Tokyo interbank market rate (TIBOR), or alternate TIBOR, if applicable, plus the applicable TIBOR margin
Debt instrument, interest rate		0.32%	0.32%	0.32%	0.32%	0.32%
Yen-denominated loan variable rate due September 2029
Debt Instrument [Line Items]
Debt instrument, principal amount \| ¥					¥ 25.0	¥ 25.0
Debt instrument, description of variable rate basis		TIBOR, or alternate TIBOR, if applicable, plus the applicable TIBOR margin
Debt instrument, interest rate		0.47%	0.47%	0.47%	0.47%	0.47%
.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%	0.963%
Notes payable
Debt Instrument [Line Items]
Debt instrument, debt default, amount \| $		$ 0	$ 0	$ 0
Lower Limit \| Yen-denominated loan variable interest rate due September 2026
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		0.30%
Lower Limit \| Yen-denominated loan variable rate due September 2029
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		0.45%
Upper Limit \| Yen-denominated loan variable interest rate due September 2026
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		0.70%
Upper Limit \| Yen-denominated loan variable rate due September 2029
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		1.00%