Contractual Commitments, Contingencies and Off-Balance Sheet Arrangements - Additional Information (Details) $ in Millions	1 Months Ended			6 Months Ended
	Dec. 31, 2019 USD ($)	Mar. 31, 2015 term	Mar. 31, 2014 term	Dec. 31, 2019 USD ($)
Contractual Commitments Contingencies And Off- Balance Sheet Arrangements [Line Items]
Payment to acquire equity method investment				$ 1.5
Remaining capital commitment	$ 0.2			0.2
Future capital commitment	$ 3.9			3.9
IT Services Agreement
Contractual Commitments Contingencies And Off- Balance Sheet Arrangements [Line Items]
IT service agreement extension term		2 years
Number of renewal terms option one | term		1
Renewal term option one (in months)		12 months
Remaining commitment amount				263.4
IBM Private Cloud Agreement
Contractual Commitments Contingencies And Off- Balance Sheet Arrangements [Line Items]
Remaining commitment amount				242.8
Agreement term	10 years 3 months
Non-cash pre-tax charge on write-down				31.8
Assets held-for-sale	$ 18.0			18.0
EU IT Services Agreement
Contractual Commitments Contingencies And Off- Balance Sheet Arrangements [Line Items]
Number of renewal terms option one | term			1
Renewal term option one (in months)			12 months
Remaining commitment amount				$ 26.3
Number of renewal terms option two | term			1
Renewal term option two (in months)			24 months