FAIR VALUE MEASUREMENTS (Details) - Recurring basis $ in Thousands	Sep. 30, 2017 USD ($)
Other assets
Assets:
Marketable equity securities	$ 3,900
Prepaid expenses and other
Assets:
Marketable equity securities	1,100
Carrying Amount
Assets:
Marketable equity securities	4,998
Liabilities:
Debt	424,794
Amount of equity component of convertible notes	77,000
Fair Value
Assets:
Marketable equity securities	4,998
Total assets	4,998
Liabilities:
Debt	409,538
Total liabilities	409,538
Level 1
Assets:
Marketable equity securities	4,998
Total assets	4,998
Liabilities:
Debt	409,538
Total liabilities	$ 409,538