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Retirement Plans (Fair Values Of The Qualified Plan's Assets) (Details) - USD ($) $ in Thousands | Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2014
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | $ 438,402 |  | $ 332,657 |  |
Cash and Cash Equivalents [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 5,479 | [1] | 3,629 | [2] |
Corporate Bonds [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [3] | 120,439 |  | 88,621 |  |
High yield |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [4] | 24,638 |  | 7,243 |  |
Alternatives |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [5] | 24,642 |  | 24,336 |  |
Real Estate [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [6] | 40,146 |  | 36,967 |  |
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 315,566 |  | 236,123 |  |
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Cash and Cash Equivalents [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 0 | [1] | 3,629 | [2] |
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Corporate Bonds [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [3] | 46,152 |  | 29,054 |  |
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | High yield |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [4] | 24,638 |  | 7,243 |  |
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Alternatives |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [5] | 24,642 |  | 24,336 |  |
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Real Estate [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [6] | 0 |  | 0 |  |
Significant Other Observable Inputs (Level 2) [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 82,690 |  | 59,567 |  |
Significant Other Observable Inputs (Level 2) [Member] | Cash and Cash Equivalents [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 5,479 | [1] | 0 | [2] |
Significant Other Observable Inputs (Level 2) [Member] | Corporate Bonds [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [3] | 74,287 |  | 59,567 |  |
Significant Other Observable Inputs (Level 2) [Member] | High yield |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [4] | 0 |  | 0 |  |
Significant Other Observable Inputs (Level 2) [Member] | Alternatives |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [5] | 0 |  | 0 |  |
Significant Other Observable Inputs (Level 2) [Member] | Real Estate [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [6] | 0 |  | 0 |  |
Significant Unobservable Inputs (Level 3) [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 40,146 |  | 36,967 |  |
Significant Unobservable Inputs (Level 3) [Member] | Cash and Cash Equivalents [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 0 | [1] | 0 | [2] |
Significant Unobservable Inputs (Level 3) [Member] | Corporate Bonds [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [3] | 0 |  | 0 |  |
Significant Unobservable Inputs (Level 3) [Member] | High yield |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [4] | 0 |  | 0 |  |
Significant Unobservable Inputs (Level 3) [Member] | Alternatives |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [5] | 0 |  | 0 |  |
Significant Unobservable Inputs (Level 3) [Member] | Real Estate [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 40,146 | [6] | 36,967 | [6] | $ 32,593
UNITED STATES | Commingled [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [7] | 101,174 |  | 83,034 |  |
UNITED STATES | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Commingled [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 101,174 | [7] | 83,034 |  |
UNITED STATES | Significant Other Observable Inputs (Level 2) [Member] | Commingled [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 0 | [7] | 0 |  |
UNITED STATES | Significant Unobservable Inputs (Level 3) [Member] | Commingled [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets |  | 0 | [7] | 0 |  |
Non-US [Member] | Commingled [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [8] | 121,884 |  | 88,827 |  |
Non-US [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Commingled [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [8] | 118,960 |  | 88,827 |  |
Non-US [Member] | Significant Other Observable Inputs (Level 2) [Member] | Commingled [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [8] | 2,924 |  | 0 |  |
Non-US [Member] | Significant Unobservable Inputs (Level 3) [Member] | Commingled [Member] |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Fair value of plan assets | [8] | $ 0 |  | $ 0 |  |
[1] | Cash and cash equivalents are comprised of commercial paper, short-term bills and notes, and short-term investment funds, which are valued at quoted prices in active markets for similar securities.
[2] | Cash and cash equivalents are comprised of commercial paper, short-term bills and notes, and short-term investment funds, which are valued at unadjusted quoted market prices.
[3] | Investment grade fixed income consists of debt obligations either issued by the US government or have a rating of BBB- / Baa or higher assigned by a major credit rating agency. These investments are valued based on unadjusted quoted market prices (Level 1), or based on quoted prices in inactive markets, or whose values are based on models, but the inputs to those models are observable either directly or indirectly (Level 2).
[4] | High yield fixed income consists primarily of debt obligations that have a rating of below BBB- / Baa or lower assigned by a major credit rating agency. These investments are valued based on unadjusted quoted market prices.
[5] | Alternative investments consists primarily of an investment in asset classes other than stocks, bonds, and cash. Alternative investments can include commodities, hedge funds, private equity, managed futures, and derivatives. These investments are valued based on unadjusted quoted market prices.
[6] | Real estate is investments in a real estate collective trust for purposes of total return. These investments are valued based on prices or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement
[7] | U.S. equity securities are comprised of investments in common stock of U.S. companies for total return purposes. These investments are valued by the trustee at closing prices from national exchanges on the valuation date.
[8] | International equity securities are comprised of investments in common stock of companies located outside of the U.S for total return purposes. These investments are valued by the trustee at closing prices from national exchanges on the valuation date, or the values are adjusted as a result of market movements following the close of local trading using inputs to models that are observable either directly or indirectly.

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