Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenues	$ 1,249.9	$ 1,224.8	$ 3,167.1	$ 3,151.0
Distribution revenues
Disaggregation of Revenue [Line Items]
Revenues	412.1	417.9	1,042.4	1,081.6
Foreign currency exchange
Disaggregation of Revenue [Line Items]
Revenues	35.8	28.9	91.6	70.9
Recurring fee revenues
Disaggregation of Revenue [Line Items]
Revenues	834.5	767.4	2,106.1	1,946.8
Event-driven fee revenues
Disaggregation of Revenue [Line Items]
Revenues	39.1	68.4	110.3	193.5
Investor Communication Solutions
Disaggregation of Revenue [Line Items]
Revenues	980.2	1,005.9	2,398.4	2,488.7
Investor Communication Solutions | Total ICS Recurring fee revenues
Disaggregation of Revenue [Line Items]
Revenues	529.0	519.6	1,245.8	1,213.6
Investor Communication Solutions | Equity proxy
Disaggregation of Revenue [Line Items]
Revenues	136.4	152.9	208.4	225.6
Investor Communication Solutions | Mutual fund and exchange traded funds (“ETF”) interims
Disaggregation of Revenue [Line Items]
Revenues	87.2	82.1	217.7	200.6
Investor Communication Solutions | Customer communications and fulfillment
Disaggregation of Revenue [Line Items]
Revenues	208.0	201.1	555.5	558.6
Investor Communication Solutions | Other ICS
Disaggregation of Revenue [Line Items]
Revenues	97.4	83.5	264.2	228.8
Investor Communication Solutions | Total ICS Event-driven fee revenues
Disaggregation of Revenue [Line Items]
Revenues	39.1	68.4	110.3	193.5
Investor Communication Solutions | Equity and other
Disaggregation of Revenue [Line Items]
Revenues	22.1	35.4	54.9	79.0
Investor Communication Solutions | Mutual funds
Disaggregation of Revenue [Line Items]
Revenues	17.0	33.1	55.3	114.5
Investor Communication Solutions | Distribution revenues
Disaggregation of Revenue [Line Items]
Revenues	412.1	417.9	1,042.4	1,081.6
Global Technology and Operations
Disaggregation of Revenue [Line Items]
Revenues	1,249.9	1,224.8	3,167.1	3,151.0
Global Technology and Operations | Total GTO Recurring fee revenues
Disaggregation of Revenue [Line Items]
Revenues	305.5	247.8	860.3	733.2
Global Technology and Operations | Equities and other
Disaggregation of Revenue [Line Items]
Revenues	259.4	206.7	727.4	612.0
Global Technology and Operations | Fixed income
Disaggregation of Revenue [Line Items]
Revenues	46.1	41.1	132.9	121.2
Global Technology and Operations | Foreign currency exchange
Disaggregation of Revenue [Line Items]
Revenues	$ 35.8	$ 28.9	$ 91.6	$ 70.9