Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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DEBT (Details) - USD ($) $ in Thousands	3 Months Ended
DEBT (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Jun. 30, 2012
Long-term debt disclosure
Principal	$ 370,000		$ 370,000
Unamortized Discount	(9,512)		(12,764)
Debt Issuance Costs	(5,549)		(6,209)
Total debt	354,939		351,027
2019 Notes
Long-term debt disclosure
Principal	370,000		370,000
Unamortized Discount	(9,512)		(12,764)
Debt Issuance Costs	(976)		(1,316)
Total debt	359,512		355,920
Principal amount of debt issued				$ 370,000
Interest rate on convertible senior notes (as a percent)				2.875%
Interest expense recognized	6,300	$ 6,000
Credit Facility
Long-term debt disclosure
Debt Issuance Costs	(4,573)		$ (4,893)
Interest expense recognized	300	$ 1,800
Maximum availability under the revolving credit facility	1,000,000
Outstanding amount under credit facility	0
Available under the revolving credit facility	$ 1,000,000