Restructuring Costs - Schedule of Restructuring Costs Incurred by Reportable Business Segment (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 30.5	$ 11.0	$ 43.8	$ 28.7
Corporate [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	11.7	5.1	12.3	16.2
Live [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	6.7	0.9	7.7	(0.6)
Learn [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	1.7	3.5	5.8	5.1
Work [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2.6		5.4	2.6
Play [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	6.3		9.0	0.3
Other [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 1.5	$ 1.5	$ 3.6	$ 5.1