Capitalization (Details) - USD ($) $ in Thousands	9 Months Ended
Jun. 30, 2018	Sep. 30, 2017
Debt Instrument [Line Items]
Common stock shares issued due to SARs exercises	68,619
Issue shares of common stock for the Direct Stock Purchase and Dividend Reinvestment Plan	138,997
Issue shares of common stock for the 401(k) plans	75,745
Shares tendered	54,329
Current Portion of Long-Term Debt	$ 250,000	$ 300,000
Debt Instrument Redeemed	$ 307,000
Restricted Stock Units [Member]
Debt Instrument [Line Items]
Common stock issued	71,918
Performance Shares [Member]
Debt Instrument [Line Items]
Common stock issued	79,079
Board Of Directors [Member]
Debt Instrument [Line Items]
Common stock issued	20,721
8.75% Notes Due May 2019 [Member]
Debt Instrument [Line Items]
Current Portion of Long-Term Debt	$ 250,000
Long-term debt, interest rate	8.75%
6.50% Notes Due April 2018 [Member]
Debt Instrument [Line Items]
Current Portion of Long-Term Debt		$ 300,000
Long-term debt, interest rate		6.50%

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, 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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Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

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