Changes in Carrying Amount of Goodwill (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014
Goodwill [Roll Forward]
Carrying amount of goodwill, December 31, 2013	$ 275,439
Currency translation adjustments	(906)
Carrying amount of goodwill, September 30, 2014	274,533
Domestic Segment
Goodwill [Roll Forward]
Carrying amount of goodwill, December 31, 2013	248,498
Currency translation adjustments	0
Carrying amount of goodwill, September 30, 2014	248,498
International Segment
Goodwill [Roll Forward]
Carrying amount of goodwill, December 31, 2013	26,941
Currency translation adjustments	(906)
Carrying amount of goodwill, September 30, 2014	$ 26,035