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Business Acquisitions, Goodwill and Intangible Assets - Goodwill (Details) $ in Thousands | 6 Months Ended
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Mar. 31, 2019 USD ($)
Changes in the carrying value of goodwill by reporting segment |
Goodwill at the beginning of the period | $ 5,921,116
Foreign Exchange Impact | (12,900)
Goodwill at the end of the period | 5,908,248
Design and Consulting Services |
Changes in the carrying value of goodwill by reporting segment |
Goodwill at the beginning of the period | 3,189,200
Foreign Exchange Impact | (9,100)
Goodwill at the end of the period | 3,180,100
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 | (4,000)
Goodwill at the end of the period | 1,004,900
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 | 200
Goodwill at the end of the period | $ 1,723,200

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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266 Reference 3: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=35741047&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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