Capital Structure - Additional Information (Detail) - USD ($)		6 Months Ended
	Apr. 18, 2015	Jun. 30, 2015
The Bain Entities [Member]
Capital Structure [Line Items]
Repurchase of common stock, shares	3,806,460	8,745,784
Repurchase price of common stock, per share	$ 77.26	$ 73.84
Percentage of discount on share repurchase	1.00%
Share repurchase program authorized amount	$ 1,000,000,000
February 2015 Repurchase Authorization [Member] | The Bain Entities [Member]
Capital Structure [Line Items]
Repurchase of common stock		12,552,244
Repurchase of common stock, per share		$ 74.88
Remaining repurchase of common stock		$ 60,000,000
May 2015 Repurchase Authorization [Member]
Capital Structure [Line Items]
Repurchase of common stock		0
May 2015 Repurchase Authorization [Member] | Maximum [Member]
Capital Structure [Line Items]
Share repurchase program authorized amount		$ 1,000,000,000