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Business Acquisitions, Goodwill and Intangible Assets - Goodwill (Details) $ in Thousands | 9 Months Ended
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Jun. 30, 2019 USD ($)
Changes in the carrying value of goodwill by reporting segment |
Goodwill at the beginning of the period | $ 5,921,116
Disposal | (400)
Foreign Exchange Impact | (14,200)
Goodwill at the end of the period | 5,906,484
Design and Consulting Services |
Changes in the carrying value of goodwill by reporting segment |
Goodwill at the beginning of the period | 3,189,200
Disposal | (400)
Foreign Exchange Impact | (6,200)
Goodwill at the end of the period | 3,182,600
Construction Services |
Changes in the carrying value of goodwill by reporting segment |
Goodwill at the beginning of the period | 1,008,900
Foreign Exchange Impact | (1,800)
Goodwill at the end of the period | 1,007,100
Management Services |
Changes in the carrying value of goodwill by reporting segment |
Goodwill at the beginning of the period | 1,723,000
Foreign Exchange Impact | (6,200)
Goodwill at the end of the period | $ 1,716,800

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- Definition Represents the amount of goodwill, disposed during period. + References No definition available. + Details
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Balance Type: | credit
Period Type: | duration

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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266 + Details
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Period Type: | instant

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- Definition Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Details
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- Details
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Period Type: |

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- Details
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