FAIR VALUE MEASUREMENTS (Details) (USD $)	Sep. 30, 2013	Jun. 30, 2013
Assets:
Marketable equity securities	$ 10,826,000	$ 9,695,000
Recurring basis | Carrying Amount
Assets:
United States treasury bills	539,991,000
Marketable equity securities	10,826,000
Liabilities:
Debt	370,000,000
Amount of equity component of convertible notes	77,000,000
Recurring basis | Fair value
Assets:
United States treasury bills	539,991,000
Marketable equity securities	10,826,000
Total assets	550,817,000
Liabilities:
Debt	356,203,000
Total liabilities	356,203,000
Recurring basis | Level 1
Assets:
United States treasury bills	539,991,000
Marketable equity securities	10,826,000
Total assets	550,817,000
Liabilities:
Debt	356,203,000
Total liabilities	$ 356,203,000