Long-Term Debt (Long Term Debt) (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Less: Total unamortized debt issuance costs	$ (11,945)	$ 0
Total long-term debt, net, excluding current maturities	1,006,493	1,230,299
Senior Notes 6.75
Debt Instrument [Line Items]
Long-term debt	500,000	0
Current portion of term loan	0	0
Term Loan Due 2022
Debt Instrument [Line Items]
Long-term debt	0	1,243,299
Current portion of term loan	0	(13,000)
Term Loan Due 2026
Debt Instrument [Line Items]
Long-term debt	523,688	0
Current portion of term loan	$ (5,250)	$ 0
Interest rate	5.55%

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

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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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