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Business Acquisitions, Goodwill and Intangible Assets - Goodwill (Details) $ in Thousands | 3 Months Ended
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Dec. 31, 2017 USD ($)
Changes in the carrying value of goodwill by reporting segment |
Goodwill at the beginning of the period | $ 5,992,881
Measurement Period Adjustments | (2,300)
Foreign Exchange Impact | 6,400
Goodwill at the end of the period | 5,997,000
Design and Consulting Services |
Changes in the carrying value of goodwill by reporting segment |
Goodwill at the beginning of the period | 3,218,900
Foreign Exchange Impact | 4,300
Goodwill at the end of the period | 3,223,200
Construction Services |
Changes in the carrying value of goodwill by reporting segment |
Goodwill at the beginning of the period | 1,049,900
Measurement Period Adjustments | (2,300)
Foreign Exchange Impact | (1,600)
Goodwill at the end of the period | 1,046,000
Management Services |
Changes in the carrying value of goodwill by reporting segment |
Goodwill at the beginning of the period | 1,724,100
Foreign Exchange Impact | 3,700
Goodwill at the end of the period | $ 1,727,800

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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=64834752&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 Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the 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 805 -SubTopic 10 -Section 25 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e961-128460 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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