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

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- Definition

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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No definition available.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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The cash outflow associated with security instruments that either represent a creditor or an ownership relationship with the holder of the investment security with a maturity of beyond one year or normal operating cycle, if longer. Includes repayments of (a) debt, (b) capital lease obligations, (c) mandatory redeemable capital securities, and (d) any combination of (a), (b), or (c).

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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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 and Credit Facilities 5.375% Senior Notes due 2020 (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2018	Jan. 31, 2017	Jun. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jan. 09, 2017	Oct. 22, 2012	Aug. 14, 2012
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 2,437,000		$ 2,137,000	$ 2,437,000	$ 2,137,000
Repayments of Long-term Debt, Long-term Capital Lease Obligations, and Capital Securities					300,000	$ 331,172
Loss on extinguishment of debt			900		910	$ 0
5.375% Senior Notes due August 15, 2020
Debt Instrument [Line Items]
Debt Instrument, Face Amount	300,000			300,000			$ 450,000
Senior Notes, Noncurrent	$ 298,759		$ 0	$ 298,759	$ 0			$ 350,000	$ 700,000
Debt Instrument, Interest Rate, Stated Percentage	5.375%		5.375%	5.375%	5.375%				5.375%
Unamortized Debt Issuance Expense	$ 1,241			$ 1,241
Repayments of Debt	$ 150,000	$ 600,000
Loss on extinguishment of debt		$ (18,600)		$ (300)