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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Contractual interest rate for funds borrowed, under the debt 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, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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LONG-TERM DEBT - Junior Lien Term Loan Agreement (Details) - USD ($) $ in Thousands	Jul. 16, 2018	Jul. 01, 2018	Dec. 31, 2017
LONG-TERM DEBT
Aggregate principal amount of outstanding, redemptions notice issued		$ 709,519
Carrying value of long-term debt		$ 688,359	$ 781,392
7.150% unsecured debentures due in 2027
LONG-TERM DEBT
Interest rate (as a percent)		7.15%	7.15%
Aggregate principal amount of outstanding, redemptions notice issued		$ 89,188
Carrying value of long-term debt		$ 85,458	$ 85,262
6.875% unsecured debentures due in 2029
LONG-TERM DEBT
Interest rate (as a percent)		6.875%	6.875%
Aggregate principal amount of outstanding, redemptions notice issued		$ 276,230
Carrying value of long-term debt		$ 262,925	$ 262,311
Forecast \| Tranche A \| Junior Lien Term Loan Credit Agreement \| The Bank of New York Mellon
LONG-TERM DEBT
Maximum borrowing capacity	$ 157,100
Forecast \| Tranche B \| Junior Lien Term Loan Credit Agreement \| The Bank of New York Mellon
LONG-TERM DEBT
Maximum borrowing capacity	193,500
Forecast \| 7.150% unsecured debentures due in 2027 \| The Bank of New York Mellon
LONG-TERM DEBT
Carrying value of long-term debt	7,100
Forecast \| 7.150% unsecured debentures due in 2027 \| Junior Lien Term Loan Credit Agreement \| The Bank of New York Mellon
LONG-TERM DEBT
Proceeds from Issuance of Long-term debt	$ 82,100
Forecast \| 7.795% tranche A junior term loan due in 2030 \| Tranche A \| The Bank of New York Mellon
LONG-TERM DEBT
Interest rate (as a percent)	7.795%
Forecast \| 6.875% unsecured debentures due in 2029 \| The Bank of New York Mellon
LONG-TERM DEBT
Carrying value of long-term debt	$ 82,800
Forecast \| 6.875% unsecured debentures due in 2029 \| Junior Lien Term Loan Credit Agreement \| The Bank of New York Mellon
LONG-TERM DEBT
Proceeds from Issuance of Long-term debt	$ 193,500
Forecast \| 6.875% unsecured debentures due in 2029 \| Tranche B \| The Bank of New York Mellon
LONG-TERM DEBT
Interest rate (as a percent)	6.875%