Restructuring Costs - Schedule of Restructuring Costs Incurred by Reportable Business Segment (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 13.3	$ 17.7
Corporate [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	0.6	11.2
Live [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	1.1	(1.7)
Learn [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	4.0	1.7
Work [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2.8	2.6
Play [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	2.7	0.3
Other [Member] | Operating Segments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 2.1	$ 3.6