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Pension Benefit Obligations (Details 2) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2015 USD ($) plan | Sep. 30, 2014 USD ($) | Sep. 30, 2013 USD ($)
Components of net periodic (benefit) cost: |  |  |
Amount, net of applicable deferred income taxes, included in other comprehensive income arising from a change in net prior service cost and net gain/loss | $ (12,953) | $ 24,161 | $ 14,582
Multiemployer Pension Plans |  |  |
Multiemployer Pension Plans |  |  |
Number of minimum construction-industry pension plans participated | plan | 200 |  |
Aggregate contributions to plans | $ 54,500 |  |
Pension Plan, Defined Benefit |  |  |
Components of net periodic (benefit) cost: |  |  |
Amount, net of applicable deferred income taxes, included in other comprehensive income arising from a change in net prior service cost and net gain/loss | 6,900 | 7,600 | 2,600
United States Pension Plan of US Entity, Defined Benefit |  |  |
Components of net periodic (benefit) cost: |  |  |
Service costs | 6,800 |  |
Interest cost on projected benefit obligation | 28,200 | 7,800 | 6,600
Expected return on plan assets | (29,400) | (8,600) | (8,500)
Amortization of net loss | 4,300 | 4,000 | 4,300
Settlement loss recognized | 600 |  |
Net periodic cost | 10,500 | 3,200 | 2,400
Amounts included in accumulated other comprehensive loss that are expected to be recognized as components of net periodic benefit cost during the next fiscal year |  |  |
Amortization of net actuarial losses | (4,000) |  |
Total | (4,000) |  |
Additional year-end information for pension plans with accumulated benefit obligations in excess of plan assets |  |  |
Projected benefit obligation | 692,500 | 217,000 | 180,300
Accumulated benefit obligation | 686,500 | 217,000 | 180,300
Fair values of plan assets | 455,600 | $ 139,700 | $ 119,800
Expected employer contributions in next fiscal year | 10,800 |  |
Minimum contribution for one of the plans | 1,300 |  |
Expected future benefit payments |  |  |
2016 | 40,600 |  |
2017 | 41,000 |  |
2018 | 40,600 |  |
2019 | 41,400 |  |
2020 | 42,800 |  |
2021-2025 | 217,000 |  |
Total | $ 423,400 |  |
Weighted-average assumptions to determine benefit obligation: |  |  |
Discount rate (as a percent) | 4.10% | 4.00% | 4.40%
Salary increase rate (as a percent) | 3.81% |  |
Weighted-average assumptions to determine net periodic benefit cost: |  |  |
Discount rate (as a percent) | 3.88% | 4.40% | 3.50%
Salary increase rate (as a percent) | 4.50% |  |
Expected long-term rate of return on plan assets (as a percent) | 6.73% | 7.50% | 7.50%
Target Allocations by Asset Category |  |  |
Target Allocations by Asset Category (as a percent) | 100.00% |  |
Percentage of Plan Assets by Asset Category |  |  |
Plan Assets by Asset Category (as a percent) | 100.00% | 100.00% |
United States Pension Plan of US Entity, Defined Benefit | Equity Securities |  |  |
Target Allocations by Asset Category |  |  |
Target Allocations by Asset Category (as a percent) | 39.00% |  |
Percentage of Plan Assets by Asset Category |  |  |
Plan Assets by Asset Category (as a percent) | 37.00% | 58.00% |
United States Pension Plan of US Entity, Defined Benefit | Debt Securities |  |  |
Target Allocations by Asset Category |  |  |
Target Allocations by Asset Category (as a percent) | 57.00% |  |
Percentage of Plan Assets by Asset Category |  |  |
Plan Assets by Asset Category (as a percent) | 59.00% | 31.00% |
United States Pension Plan of US Entity, Defined Benefit | Cash and Cash Equivalents |  |  |
Target Allocations by Asset Category |  |  |
Target Allocations by Asset Category (as a percent) | 1.00% |  |
Percentage of Plan Assets by Asset Category |  |  |
Plan Assets by Asset Category (as a percent) | 1.00% | 1.00% |
United States Pension Plan of US Entity, Defined Benefit | Property and Other |  |  |
Target Allocations by Asset Category |  |  |
Target Allocations by Asset Category (as a percent) | 3.00% |  |
Percentage of Plan Assets by Asset Category |  |  |
Plan Assets by Asset Category (as a percent) | 3.00% | 10.00% |
Foreign Pension Plan, Defined Benefit |  |  |
Components of net periodic (benefit) cost: |  |  |
Service costs | $ 1,100 | $ 700 | $ 900
Interest cost on projected benefit obligation | 47,100 | 27,900 | 23,800
Expected return on plan assets | (49,400) | (26,100) | (22,700)
Amortization of prior service cost | (200) | (200) | (200)
Amortization of net loss | 5,900 | 4,900 | 4,000
Settlement loss recognized | 700 | 400 | 2,600
Net periodic cost | 5,200 | 7,600 | 8,500
Amounts included in accumulated other comprehensive loss that are expected to be recognized as components of net periodic benefit cost during the next fiscal year |  |  |
Amortization of prior service credit | (200) | (200) | (200)
Amortization of net actuarial losses | (5,700) |  |
Total | (5,500) |  |
Additional year-end information for pension plans with accumulated benefit obligations in excess of plan assets |  |  |
Projected benefit obligation | 1,226,200 | 658,500 | 601,700
Accumulated benefit obligation | 1,222,000 | 656,300 | 599,800
Fair values of plan assets | 911,200 | $ 513,400 | $ 469,000
Expected employer contributions in next fiscal year | 20,700 |  |
Expected future benefit payments |  |  |
2016 | 37,400 |  |
2017 | 41,200 |  |
2018 | 44,400 |  |
2019 | 41,400 |  |
2020 | 43,100 |  |
2021-2025 | 242,500 |  |
Total | $ 450,000 |  |
Weighted-average assumptions to determine benefit obligation: |  |  |
Discount rate (as a percent) | 3.80% | 3.94% | 4.44%
Salary increase rate (as a percent) | 2.51% | 2.38% | 2.58%
Weighted-average assumptions to determine net periodic benefit cost: |  |  |
Discount rate (as a percent) | 3.92% | 4.44% | 4.39%
Salary increase rate (as a percent) | 2.65% | 2.58% | 2.36%
Expected long-term rate of return on plan assets (as a percent) | 6.00% | 5.40% | 5.11%
Target Allocations by Asset Category |  |  |
Target Allocations by Asset Category (as a percent) | 100.00% |  |
Percentage of Plan Assets by Asset Category |  |  |
Plan Assets by Asset Category (as a percent) | 100.00% | 100.00% |
Foreign Pension Plan, Defined Benefit | Equity Securities |  |  |
Target Allocations by Asset Category |  |  |
Target Allocations by Asset Category (as a percent) | 30.00% |  |
Percentage of Plan Assets by Asset Category |  |  |
Plan Assets by Asset Category (as a percent) | 27.00% | 28.00% |
Foreign Pension Plan, Defined Benefit | Debt Securities |  |  |
Target Allocations by Asset Category |  |  |
Target Allocations by Asset Category (as a percent) | 30.00% |  |
Percentage of Plan Assets by Asset Category |  |  |
Plan Assets by Asset Category (as a percent) | 30.00% | 33.00% |
Foreign Pension Plan, Defined Benefit | Cash and Cash Equivalents |  |  |
Target Allocations by Asset Category |  |  |
Target Allocations by Asset Category (as a percent) | 10.00% |  |
Percentage of Plan Assets by Asset Category |  |  |
Plan Assets by Asset Category (as a percent) | 4.00% | 3.00% |
Foreign Pension Plan, Defined Benefit | Property and Other |  |  |
Target Allocations by Asset Category |  |  |
Target Allocations by Asset Category (as a percent) | 30.00% |  |
Percentage of Plan Assets by Asset Category |  |  |
Plan Assets by Asset Category (as a percent) | 39.00% | 36.00% |

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- Definition Amount of net gain (loss) recognized in net periodic benefit cost as a result of 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 30 -Section 15 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927 Reference 2: 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=35743120&loc=d3e1928-114920 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Service Cost (Component of Net Periodic Pension Cost) -URI http://asc.fasb.org/extlink&oid=6525008 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=35743120&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=35743120&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=35743120&loc=d3e1928-114920 + Details
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- Definition Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held. + 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) -URI http://asc.fasb.org/extlink&oid=35743120&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)(1) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. + 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 (g) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition Amount of contributions made to the multiemployer plan by all employers who participate in the plan. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 7 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=35742057&loc=SL14450678-114947 + Details
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- Definition Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i-k) -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580 + Details
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