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Retirement Plans (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2013
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Contributions by Employer |  | $ 1.2 |  |
Percentage of Obligations Related to U.S. Plan |  | 98.00% |  |
Defined Benefit Plan, Target Plan Asset Allocations |  | 100.00% |  |
Defined Contribution Plan, Cost Recognized |  | $ 6.2 | $ 5.6 | $ 5.1
Percentage of Assets Related to U.S. Plan |  | 98.00% |  |
Minimum [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan Expected Return on Plan Assets Major Asset Classes Time Horizon |  | 10 |  |
Maximum [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan Expected Return on Plan Assets Major Asset Classes Time Horizon |  | 15 |  |
Pension Plan, Defined Benefit [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Contributions by Employer |  |  | 0.1 |
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements and Curtailments |  | $ (0.5) | $ (0.2) | $ (0.1)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate |  | 4.84% | 4.49% | 5.16%
Discount rate |  | 4.49% | 5.16% | 4.21%
Equity Securities [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations |  | 40.00% |  |
Fixed Income Funds [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Target Plan Asset Allocations |  |  | 60.00% |
Scenario, Forecast [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Pension Contributions | $ 0.8 |  |  |

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- Definition Defined Benefit Plan, Expected Return on Plan Assets, Major Asset Classes, Time Horizon + References No definition available. + Details
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- Definition Percentage of total pension plan assets held by the Company's to U.S. pension plan. + References No definition available. + Details
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- Definition The interest rate used to adjust for the time value of money for the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition The interest rate used to adjust for the time value of money. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition The increase in the fair value of plan assets from contributions made by the employer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Amount of net gain (loss) recognized in net periodic benefit cost due to settlements and curtailments. Curtailments result from 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. Settlements result from an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Target allocation of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition The amount of cash or cash equivalents contributed by the entity to fund its pension plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585 + Details
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