Summary of Goodwill (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Goodwill [Line Items]
Beginning Balance	$ 1,277,383	[1]
Foreign currency translation adjustments	(11,958)
Ending Balance	1,265,425	[1]
U.S. Operating Segment
Goodwill [Line Items]
Beginning Balance	1,156,556	[1]
Foreign currency translation adjustments	0
Ending Balance	1,156,556	[1]
International Operating Segment
Goodwill [Line Items]
Beginning Balance	120,827	[1]
Foreign currency translation adjustments	(11,958)
Ending Balance	$ 108,869	[1]

[1] Balances are presented net of accumulated impairment losses of $214,031 for the U.S. operating segment and $27,622 for the international operating segment.