Acquisitions (Narrative) (Details) $ in Millions	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Number of acquisitions completed	0
2018 Business Combinations
Business Acquisition [Line Items]
Number of acquisitions completed		3
Business combinations, aggregate purchase price, net of cash acquired		$ 237.1

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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