Goodwill (Schedule of Goodwill) (Details) $ in Thousands	3 Months Ended
Dec. 31, 2020 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning of the period	$ 397,205
Business combinations	6,088
Measurement period adjustment	72
Foreign currency translation	5,228
Goodwill, end of the period	408,593
Operating Segments \| Integrated Solutions and Services
Goodwill [Roll Forward]
Goodwill, beginning of the period	224,381
Business combinations	6,088
Measurement period adjustment	72
Foreign currency translation	1,990
Goodwill, end of the period	232,531
Operating Segments \| Applied Product Technologies
Goodwill [Roll Forward]
Goodwill, beginning of the period	172,824
Measurement period adjustment	0
Foreign currency translation	3,238
Goodwill, end of the period	176,062
Goodwill, Written off Related to Sale of Business Unit	$ 0

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.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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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.

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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.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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