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The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan in the current remaining fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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The amount of gains or losses recognized in net periodic benefit cost

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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

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The amount of the transition obligation or asset recognized in net periodic benefit cost.

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The interest rate used to adjust for the time value of money.

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An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

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- Definition

Expected rate of compensation increases (for pay-related plans).

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The amount of contributions made by the employer.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain or loss, prior service cost or credit, transition asset or obligation, and gain or loss due to settlements or curtailments).

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The amount of net gain or loss recognized in net periodic benefit cost as a result of an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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Interim Pension and Other Postretirement Benefits (Details) (USD $)			3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended			9 Months Ended
	Jun. 30, 2011	Sep. 30, 2010	Jun. 30, 2011 Pension Plans Defined Benefit [Member]	Jun. 30, 2010 Pension Plans Defined Benefit [Member]	Jun. 30, 2011 Pension Plans Defined Benefit [Member]	Jun. 30, 2010 Pension Plans Defined Benefit [Member]	Jun. 30, 2011 Other Postretirement Benefit Plans Defined Benefit [Member]	Jun. 30, 2010 Other Postretirement Benefit Plans Defined Benefit [Member]	Jun. 30, 2011 Other Postretirement Benefit Plans Defined Benefit [Member]	Jun. 30, 2010 Other Postretirement Benefit Plans Defined Benefit [Member]	Sep. 30, 2011 Other Postretirement Benefit Plans Defined Benefit [Member]	Jun. 30, 2011 Other Pension Plans Defined Benefit [Member]	Jun. 30, 2010 Other Pension Plans Defined Benefit [Member]	Jun. 30, 2011 Money Market Funds [Member]	Sep. 30, 2010 Money Market Funds [Member]	Jun. 30, 2011 Equity Funds Domestic [Member]	Sep. 30, 2010 Equity Funds Domestic [Member]	Jun. 30, 2011 Equity Funds Foreign [Member]	Sep. 30, 2010 Equity Funds Foreign [Member]
Defined Benefit Plan Weighted Average Assumptions Used In Calculating Net Periodic Benefit Cost Abstract
Discount Rate					5.68%	5.52%			5.39%	5.52%		5.39%	5.52%
Rate of compensation increase					4.00%	4.00%			4.00%	4.00%		4.00%	4.00%
Expected return on plan assets					8.25%	8.25%			5.00%	5.00%		8.25%	8.25%
Components of net periodic pension cost [Abstract]
Service Cost			$ 4,257,000	$ 3,993,000	$ 12,894,000	$ 11,982,000	$ 3,601,000	$ 3,360,000	$ 10,803,000	$ 10,077,000
Interest Cost			7,055,000	6,524,000	21,034,000	19,569,000	3,204,000	3,018,000	9,610,000	9,051,000
Expected return on assets			6,285,000	6,320,000	18,533,000	18,960,000	681,000	615,000	2,045,000	1,845,000
Amortization of transition asset			0	0	0	0	377,000	377,000	1,133,000	1,134,000
Amortization of prior service cost			(106,000)	(193,000)	(323,000)	(582,000)	(362,000)	(375,000)	(1,087,000)	(1,125,000)
Recognized actuarial loss			(2,748,000)	(2,822,000)	(8,990,000)	(8,469,000)	(87,000)	(93,000)	(260,000)	(282,000)
Curtailment Loss			0	0	40,000	0	0	0	0	0
Defined Benefit Plan Net Periodic Benefit Cost			7,669,000	6,826,000	24,022,000	20,478,000	6,226,000	5,858,000	18,674,000	17,574,000
Current Year Benefit Plan Contributions [Abstract]
Contributions Actual							8,700,000
Contributions Estimate											12,000,000
Available-for-sale Securities Amortized Cost Basis [Abstract]
Amortized Cost	35,002,000	34,792,000												2,812,000	499,000	27,593,000	29,540,000	4,597,000	4,753,000
Gross Unrealized Gain	9,043,000	6,674,000												0	0	7,627,000	5,698,000	1,416,000	976,000
Gross Unrealized Loss	0	0												0	0	0	0	0	0
Fair value	$ 44,045,000	$ 41,466,000												$ 2,812,000	$ 499,000	$ 35,220,000	$ 35,238,000	$ 6,013,000	$ 5,729,000