NOTES PAYABLE - Additional Information (Details) - 3 months ended Mar. 31, 2016 ¥ in Millions	USD ($)	JPY (¥)
Notes Payable
Debt Instrument [Line Items]
Debt instrument, debt default, amount	$ 0
100 billion yen line of credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity | ¥		¥ 100,000
Line of credit facility term	3 years
Line of credit facility, interest rate description	Borrowings bear interest at a rate per annum equal to the Tokyo interbank market rate (TIBOR) plus, at our option, either (a) the applicable TIBOR margin during the period from the closing date to the commitment termination date or (b) the applicable TIBOR margin during the term out period. The applicable margin ranges between .35% and .75% during the period from the closing date to the commitment termination date and .70% and 1.50% during the term out period, depending on the Parent Company’s debt ratings as of the date of determination.
Line of credit facility, amount outstanding | ¥		0
$100 million dollar line of credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 100,000,000
Line of credit facility term	364 days
Line of credit facility, interest rate description	Borrowings will bear interest at the rate quoted by the bank and agreed upon at the time of making such loan and will have a three-month maturity period.
Line of credit facility, amount outstanding	$ 0
55 billion yen line of credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity | ¥		55,000
Line of credit facility term	5 years
Line of credit facility, interest rate description	Borrowings bear interest at a rate per annum equal to, at our option, either (a) a eurocurrency rate determined by reference to the London Interbank Offered Rate (LIBOR) for the interest period relevant to such borrowing adjusted for certain additional costs or (b) a base rate determined by reference to the highest of (1) the federal funds effective rate plus ½ of 1%, (2) the rate of interest for such day announced by Mizuho Bank, Ltd. as its prime rate and (3) the eurocurrency rate for an interest period of one month plus 1.00%, in each case plus an applicable margin. The applicable margin ranges between .79% and 1.275% for eurocurrency rate borrowings and 0.0% and .275% for base rate borrowings, depending on the Parent Company’s debt ratings as of the date of determination.
Line of credit facility, amount outstanding | ¥		¥ 0
$50 million dollar line of credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 50,000,000
Line of credit facility, interest rate description	Borrowings will bear interest at the rate quoted by the bank and agreed upon at the time of making such loan and will have a three-month maturity period.
Line of credit facility, amount outstanding	$ 0
Line of credit
Debt Instrument [Line Items]
Debt instrument, debt default, amount	$ 0
Lower Limit | 100 billion yen line of credit
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage	0.30%
Lower Limit | 55 billion yen line of credit
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage	0.085%
Upper Limit | 100 billion yen line of credit
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage	0.50%
Upper Limit | 55 billion yen line of credit
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage	0.225%