Unconsolidated Affiliates (Details) ft² in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016 USD ($) ft²	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) ft²	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Schedule of Equity Method Investments [Line Items]
Carrying value	$ 331.2				$ 312.2				$ 331.2	$ 312.2
Equity in earnings of unconsolidated affiliates	$ 3.3	$ 7.0	$ 10.2	$ 6.7	6.2	$ 11.8	$ 12.7	$ 14.7	$ 27.2	45.4	$ 34.7
International Financial Data Services U.K.
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%								50.00%
Carrying value	$ 133.3				124.3				$ 133.3	124.3
Equity in earnings of unconsolidated affiliates									$ 10.0	22.5	12.6
International Financial Data Services L.P.
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%								50.00%
Carrying value	$ 73.2				75.2				$ 73.2	75.2
Equity in earnings of unconsolidated affiliates									$ 2.2	7.4	6.5
Boston Financial Data Services, Inc.
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%								50.00%
Carrying value	$ 91.2				82.9				$ 91.2	82.9
Equity in earnings of unconsolidated affiliates									8.3	5.3	5.1
Other unconsolidated affiliates
Schedule of Equity Method Investments [Line Items]
Carrying value	$ 33.5				29.8				33.5	29.8
Equity in earnings of unconsolidated affiliates									$ 6.7	10.2	$ 10.5
Pershing Road Development Company, LLC
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%								50.00%
Carrying value	$ 0.0				$ 0.0				$ 0.0	$ 0.0
Pershing Road Development Company, LLC | Office space | U.S. government
Schedule of Equity Method Investments [Line Items]
Approximate square feet of office space | ft²	1.1								1.1