Condensed Consolidated Balance Sheets (unaudited) Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2014	Sep. 30, 2013	Mar. 31, 2013
Statement of Financial Position [Abstract]
Allowance for doubtful accounts on accounts receivable	$ 12,098	$ 5,519	$ 8,052
Accumulated depreciation and amortization on property, plant and equipment	$ 877,460	$ 853,675	$ 837,110
Common stock, par value	$ 2.25	$ 2.25	$ 2.25
Common stock, shares authorized	40,000,000	40,000,000	40,000,000
Common stock, shares issued	26,781,785	26,781,785	26,781,785
Common stock, shares outstanding	26,781,785	26,781,785	26,781,785