Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended										12 Months Ended
	Dec. 31, 2015		Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014		Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Effect of Fourth Quarter Events [Line Items]
Revenues	$ 751.8		$ 741.6	$ 716.7	$ 740.5	$ 763.9		$ 749.5	$ 736.4	$ 605.7	$ 2,950.6	$ 2,855.5	$ 2,046.1
Operating income (loss)	61.1	[1]	47.8	36.3	49.2	49.9	[2]	42.0	36.9	22.0	194.4	150.8	137.4
Net income (loss) from continuing operations	42.6		57.6	29.0	39.3	48.0		30.0	24.9	13.7	168.4	116.5	58.5
Net income (loss) from discontinued operations	0.0		0.5	0.0	0.1	0.4		2.8	(0.2)	0.5	(0.6)	(3.5)
Net (loss) income	42.6		$ 58.1	$ 29.0	$ 39.4	48.4		$ 32.8	$ 24.7	$ 14.2	169.0	$ 120.0	$ 60.9
Change in Operating Income	13.4					16.7
Business Combination, Integration Related Costs	3.5					2.2
Step-up Depreciation	3.6					5.6
Amortization of Intangible Assets	$ 6.3					7.2
Foreign Earnings Repatriated						(4.5)					$ (1.9)
Settlement (gain) loss recognized during the period						$ (1.7)
Basic earnings (loss) per share:
Continuing operations	$ 0.44		$ 0.59	$ 0.29	$ 0.40	$ 0.48		$ 0.30	$ 0.25	$ 0.14	$ 1.72	$ 1.16	$ 0.57
Discontinued operations	0.00		0.00	0.00	0.00	0.00		0.03	0.00	0.00	0.01	0.03	0.02
Net basic earnings (loss) per common share	0.44		0.59	0.29	0.40	0.48		0.33	0.25	0.14	1.73	1.19	0.59
Diluted earnings (loss) per share
Continuing operations	0.41		0.55	0.28	0.37	0.46		0.28	0.23	0.13	1.60	1.10	0.54
Discontinued operations	0.00		0.01	0.00	0.00	0.00		0.03	0.00	0.00	0.01	0.03	0.02
Net basic earnings (loss) per common share	$ 0.41		$ 0.56	$ 0.28	$ 0.37	$ 0.46		$ 0.31	$ 0.23	$ 0.13	$ 1.61	$ 1.13	$ 0.56
Pension Plan, Defined Benefit [Member]
Effect of Fourth Quarter Events [Line Items]
Settlement (gain) loss recognized during the period											$ 0.0	$ (4.6)	$ (13.4)
Other Pension Plan, Defined Benefit [Member]
Effect of Fourth Quarter Events [Line Items]
Settlement (gain) loss recognized during the period											$ 0.0	$ 0.0	$ 0.3

[1] Fourth quarter 2015 includes a decrease in operating income of $13.4 resulting from $3.5 of integration related expenses associated with Convergys’ acquisition of Stream, $3.6 of depreciation expense resulting from the fair value write-up of property and equipment acquired from Stream, and $6.3 of amortization expense related to acquired intangible assets. Fourth quarter 2015 also includes $1.9 of tax expense for a change in estimate between tax previously accrued for the repatriation of foreign earnings and the revised estimates as of December 31, 2015.

[2] Fourth quarter 2014 includes a decrease in operating income of $16.7 resulting from $2.2 of integration related expenses associated with Convergys’ acquisition of Stream, $1.7 of pension settlement charge, $5.6 of depreciation expense resulting from the fair value write-up of property and equipment acquired from Stream, and $7.2 of amortization expense related to acquired intangible assets. Fourth quarter 2014 also includes $4.5 of tax benefit for a change in estimate between tax previously accrued for the repatriation of foreign earnings and the revised estimates as of December 31, 2014.