Corporate Investments and Funds Held For Clients (Classification Of Corporate Investments On The Consolidated Balance Sheets) (Details) - USD ($) $ in Millions		Sep. 30, 2019		Jun. 30, 2019	Sep. 30, 2018
Corporate Investments And Funds Held For Clients [Abstract]
Cash and cash equivalents		$ 1,403.9		$ 1,949.2	$ 1,490.3
Short-term marketable securities		3,545.1	[1]	10.5
Long-term marketable securities	[2]	576.0		261.4
Total corporate investments		$ 5,525.0		$ 2,221.1

[1] (B) The Company reclassified $3,535.5 million of funds held for clients to short-term marketable securities as a result of proceeds from commercial paper borrowings as of September 30, 2019 which were utilized to pay our client obligations.

[2] (a) - Long-term marketable securities are included within Other assets on the Consolidated Balance Sheets.